PPC 2023: XVI International Conference on Interactions between Particle Physics and Cosmology

12 Jun 2023, 09:00 → 16 Jun 2023, 18:00 Asia/Seoul

Science and Culture Center (IBS)

The 16th International Conference on Interconnections between Particle Physics and Cosmology (PPC 2023), hosted by the Institute for Basic Science (IBS) will take place in Daejeon, Korea, June 12-16. 

PPC aims to bring together the world-class experts in particle physics, cosmology, and astrophysics for active discussions and interdisciplinary collaborations among different fields. We hope to provide exciting opportunities to develop new directions and/or breakthroughs in understanding the principles of our universe. 

PPC 2023 will be followed by a satellite workshop: The 1st Workshop on Boosted Dark Matter (BDM 2023). The workshop webpage is https://sites.google.com/jbnu.ac.kr/bdm2023 .

Scientific Program

• Astroparticle Physics
• BSM Theories
• Collider Physics
• Cosmology
• Dark Matter Physics
• Flavor Physics
• Gravitational Waves
• Neutrino Physics

 

Local Organizing Committee

International Advisory Committee

Sang Hyeon Chang (IBS-CTPU) Kiwoon Choi (IBS-CTPU) Ki Young Choi (Sungkyunkwan U.) Koun Choi (IBS-CUP)  Junghwan Goh (Kyung Hee U.) Jinn-Ouk Gong (Ewha Womans U.) Chang Hyon Ha (Chung-Ang U.) Sang Hui Im (IBS-CTPU)  Hyun Su Lee (IBS-CUP) Jong-Chul Park (Chungnam Nat’l U. / IBS-CTPU)   Jung Sic Park (Kyungpook Nat’l U.)  Sunny Seo (IBS-CUP)  Chang Sub Shin (Chungnam Nat’l U. / IBS-CTPU)  Seodong Shin (Jeonbuk Nat’l U. / IBS-CTPU)  Hwidong Yoo (Yonsei U.)  Sung Woo Youn (IBS-CAPP)

Ben Allanach (Cambridge) Vernon Barger (Wisconsin) V. A. Bednyakov (JINR) Joel Butler (FNAL/CERN) Tiziano Camporesi (CERN) John Ellis (King's College/CERN) JoAnne Hewett (SLAC) Ian Hinchliffe (LBL) Fabio Iocco (ICTP-SAIFR) Karl Jakobs (U. Freiburg) Gordon Kane (Michigan) Dmitri I. Kazakov (JINR, Dubna) Robert Kirshner (Harvard) Tomio Kobayashi (Tokyo) Pran Nath (Northeastern) Mihoko Nojiri (KEK) Saul Perlmutter (LBNL) Michael Peskin (SLAC) Adam Riess (Johns Hopkins) Paul Shapiro (UT Austin) Melvyn Shochet (Chicago) George F. Smoot (UC Berkeley) David Spergel (Princeton) Paris Sphicas (CERN/Athens) S.C.C. Ting (MIT)

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(주) 더마이스터

#1801, 18F, 136, Cheongsa-ro, Seo-gu, Daejeon 35220, Korea
Tel +82-42-489-7070 | E-mail ppc2023@themiceter.com
Registration No. : 292-87-00916 / Representative : Jong-min Hong

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Monday, 12 June

09:00 → 09:30 Registration & Welcome

09:30 → 10:30 Plenary: Collider 1

Plenary I

Convener: Seong Youl Choi

09:30 Theoretical Perspectives on Higgs Physics

Speaker: Christophe Grojean (DESY)

Grojean.pdf

10:00 BSM Higgs sectors, triple Higgs couplings and gravitational waves

Speaker: Sven Heinemeyer (IFT (CSIC))

sven.pdf

10:30 → 11:00 Coffee & Break

11:00 → 12:30 Plenary: Cosmology 1

Convener: Jinn-Ouk Gong

11:00 Inflation in Cosmology

Speaker: Prof. Gonzalo Palma (University of Chile)

palma-ppc-2023.pdf

11:30 Density perturbation in Cosmology

Speaker: Jai-chan Hwang

PPC2023-hwang.pptx

12:00 Recent topics on cosmology with primordial black holes and their implications for particle physics

Speaker: Kazunori Kohri (KEK / Sokendai / Kavli IPMU)

Kohri-IBS-20230612.pdf

12:30 → 14:00 Lunch

14:00 → 16:00 Parallel: Cosmology 1

Convener: Ki-Young Choi (Sungkyunkwan University)

14:00 Search for primordial features in the CMB power spectrum and bispectrum

Numerous physically well-motivated early universe models predict mild oscillations in the primordial spectra. We present our recent research on finding hints of primordial features in the CMB. First, we use and develop a free-form reconstruction technique on the CMB power spectrum to obtain a form of primordial power spectrum which fits both the temperature and polarisation data well. The method is further improved by introducing regularisation methods inspired by image analysis. Second, we present our newly developed public code CMB-BEST (CMB Bispectrum ESTimator) for constraining primordial non-Gaussianity. The independent code can constrain a wide range of models including highly oscillatory bispectrum templates predicted by models with features. Our findings are discussed in the context of the look-elsewhere effect. Some future prospects for upcoming CMB surveys are provided.

Speaker: Wuhyun Sohn (Korea Astronomy & Space Science Institute)

SOHN.pdf

SOHN.pptx

14:20 Continuous spectrum on cosmological collider

The cosmological collider program is to find a new massive particle from non-Gaussianity of the curvature perturbation. In this work, we study the effects of a massive field with a "continuous" spectrum on the non-Gaussianity. This kind of continuous spectrum is motivated by several extra dimensional models. We find that in contrast to the usual case without the continuous spectrum, the amplitude of the inflationary three-point correlation function has a damping feature in the deep squeezed limit, which can be strong evidence for the continuous spectrum.

Speaker: Shuntaro Aoki (Chung-Ang University)

PPC2023_Aoki.pdf

14:40 Primordial black holes from inflation: dark matter, gravitational waves and imprints from evaporation

Primordial black holes (PBH) have recently emerged as very interesting candidates for the cold dark matter in the universe. We study the generation of PBHs in a single field model of inflation with an inflection point in the inflaton potential. We found that PBHs can be produced in our scenario in the asteroid-mass window with a nearly monochromatic mass fraction which can account for the total dark matter in the universe. Further, we study the induced stochastic gravitational waves background (ISGWB) arising from the second order scalar perturbations. We found that the ISGWB in our scenario can be generated in the frequencies range from nanoHz to KHz that covers the observational scales corresponding to future space based GW observatories such as IPTA, LISA, DECIGO and ET as well as Advanced LIGO and BBO. Finally, we study the observational signatures due to the Hawking evaporation of ultra-light PBHs. While stable heavy particles from evaporation can be an interesting dark matter candidate, we find that light relativistic particles can also contribute to the effective relativistic degree of freedom which can be constrained by future CMB experiments.

Speaker: Rajeev Kumar Jain (Dept. of Physics, Indian Institute of Science, Bangalore 560012, India)

Talk-PPC2023-RKJain.pdf

15:00 Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing

Gravitational lensing deflects the paths of photons, altering the statistics of cosmic backgrounds and distorting their information content. We take the Cosmic Infrared Background (CIB), which provides a wealth of information about galaxy formation and evolution, as an example to probe the effect of gravitational lensing on non-Gaussian statistics. Using the Websky simulations, we first quantify the non-Gaussianity of the CIB, revealing additional detail on top of its well-measured power spectrum. To achieve this, we use needlet-like multipole-band-filters to calculate the variance and higher-point correlations. We show the 3-point and 4-point spectra, and compare our calculated bispectra to Planck values. We then lens the CIB, shell-by-shell with corresponding convergence maps, to capture the broad redshift extent of both the CIB and its lensing convergence. Using our simulations, we show that the lensed CIB power spectrum and bispectrum agree with observations: the lensing of the CIB changes the 3-point and 4-point functions by a few tens of percent at large scales, unlike with the power spectrum, which changes by less than two percent. We expand our analyses to encompass the full intensity probability distribution functions (PDFs) involving all n-point correlations as a function of scale. In particular we use the relative entropy between lensed and unlensed PDFs to create a spectrum of templates that can allow estimation of lensing. The underlying CIB model has uncertainties, in particular missing the important role of star-bursting, which has a larger effect on higher point correlations than on the variance. We test this by adding a stochastic log-normal term to the intensity distributions. The novel aspects of our filtering and lensing pipeline should prove useful for not just CIB applications, but for any radiant background, including line intensity maps.

Speaker: Mr Jaemyoung Lee (University of Pennsylvania)

Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Gravitational Lensing

15:20 Composite Dilaton Inflation

This work investigates the possibility that our inflation originates from a composite theory. Taking an 𝑆𝑈(𝑁𝑐) gauge theory with 𝑁𝑓 fermions in the fundamental representation, we consider an effective chiral Lagrangian involving a dilaton and pions. The walking dynamics of the theory constrain the potential specifics. We identify the dilaton as the inflaton, which resembles a hybrid inflation with the pions acting as a waterfall field in the potential. Analyzing the inflationary dynamics, we find a parameter region supporting small-field inflation compatible with Planck 2018 inflationary observables. We further discuss possible phenomenological consequences of this theory.

Speaker: Dhong Yeon Cheong (Yonsei University)

PPC_2023_CHEONG.pdf

15:40 Inflation and tachyonic preheating with twin waterfalls

In view of the improving measurements of the tensor-to-scalar ratio, hybrid inflation remains a suitable mechanism to achieve low-scale inflation. However, as originally proposed, hybrid inflation with a single waterfall field gives rise to a hierarchy problem, also known as the 𝜂 problem. In this work, we consider an extension to the original model in which twin waterfall fields, related by a 𝑍2 symmetry, ensure the flatness of the inflationary potential. We study the initial conditions required for successful inflation and the post-inflationary epochs of perturbative reheating and tachyonic preheating. We also comment on how our model can arise from a microscopical dark QCD model.

Speaker: Adriana Menkara (Chung Ang University)

PPC_Adriana_v2.pdf

14:00 → 16:00 Parallel: Dark Matter 1

Convener: Dr hyunsu Lee (IBS)

14:00 Status of COSINE-100

The DAMA/LIBRA collaboration has been observing an annual modulation signal expected to be caused by the dark matter interaction with their NaI(Tl) crystal detectors. There have been many global efforts to test the signal, and COSINE-100 is an experiment to verify it also using NaI(Tl) detectors. Data have been reliably acquired for 6.5 years since September 2016 at the Yangyang Underground Laboratory. The experiment has paused since march this year for a detector upgrade and move to the recently completed Yemilab in Jeongseon. The analysis of the six years of data is nearing completion, and we have achieved better background modeling and event selection than before. The COSINE collaboration is also focusing on the detector upgrade, and we expect an effective increase in target mass and an improvement in light yield. The deeper underground laboratory and the around -30 degrees Celsius environment will also likely lead to improvements. In this presentation, the status of the analysis so far and the installation plans for the next phase will be presented, along with the goals of the COSINE collaboration after the validation of DAMA/LIBRA, including several feasibility tests.

Speaker: Yongju Ko (IBS-CUP)

20230612_COSINE_yjko.pdf

14:20 ANAIS−112: updated results on annual modulation with three-year exposure and future prospects

Speaker: Prof. Maria Martinez (Universidad de Zaragoza)

PPC23_MMartinez.pdf

14:40 The SABRE South Experiment at the Stawell Underground Physics Laboratory

The SABRE (Sodium iodide with Active Background REjection) experiment aims to detect an annual rate modulation from dark matter interactions in ultra-high purity NaI(Tl) crystals in order to provide a model independent test of the signal observed by DAMA/LIBRA. It is made up of two separate detectors; SABRE South located at the Stawell Underground Physics Laboratory (SUPL), in regional Victoria, Australia, and SABRE North at the Laboratori Nazionali del Gran Sasso (LNGS).
SABRE South is designed to disentangle seasonal or site-related effects from the dark matter-like modulated signal by using an active veto and muon detection system. Ultra-high purity NaI(Tl) crystals are immersed in a linear alkyl benzene (LAB) based liquid scintillator veto, further surrounded by passive steel and polyethylene shielding and a plastic scintillator muon veto. Significant work has been undertaken to understand and mitigate the background processes that take into account radiation from detector materials, from both intrinsic and cosmogenic activated processes, and to understand the performance of both the crystal and veto systems.
SUPL is a newly built facility located 1024 m underground (~2900m water equivalent) within the Stawell Gold Mine and its construction was completed in mid-2022. It will house rare event physics searches, including the SABRE dark matter experiment, as well as measurement facilities to support low background physics experiments and applications such as radiobiology and quantum computing. The SABRE South commissioning is expected to occur this year.
This talk will report on the design of SUPL and the construction and commissioning of SABRE South.

Speaker: Dr Matthew Gerathy (University of Melbourne)

SABRE_PPC2023.pdf

15:00 Recent results from the PandaX experiment

PandaX experiment uses xenon as the target to detect weak and rare physics signals, including dark matter and neutrinos at CJPL in China. The new generation detector with 4-ton xenon in the sensitive volume, PandaX-4T, has pushed the constraints on WIMP-nucleon scattering cross-section to a new level with its commissioning run data. In this talk, I will give an overview of PandaX-4 T's latest results on dark matter and neutrino physics, exploring the physics capability of the xenon detector.

Speaker: Ms Xuyang Ning (Shanghai Jiao Tong University)

PPC2023-v3.pdf

15:20 Recent status and prospects of CDEX@CJPL

Speaker: Mr Rui Xu (Tsinghua University)

PPC2023-Recent status and prospects of CDEX dark matter search at CLPL_XuRui_20230612.pdf

14:00 → 16:00 Parallel: Neutrino 1

Convener: Koun Choi (IBS)

14:00 Scattering and Neutrino Detector at the LHC

SND@LHC is a compact and stand-alone experiment to perform measurements with neutrinos produced at the LHC in a hitherto unexplored pseudo-rapidity region of 7.2 < 𝜂 < 8.6, complementary to all the other experiments at the LHC. The experiment is located 480 m downstream of IP1 in the unused TI18 tunnel. The detector is composed of a hybrid system based on an 800 kg target mass of tungsten plates, interleaved with emulsion and electronic trackers, followed downstream by a calorimeter and a muon system. The configuration allows efficiently distinguishing between all three neutrino flavours, opening a unique opportunity to probe physics of heavy flavour production at the LHC in the region that is not accessible to ATLAS, CMS and LHCb. This region is of particular interest also for future circular colliders and for predictions of very high-energy atmospheric neutrinos. The detector concept is also well suited to searching for Feebly Interacting Particles via signatures of scattering in the detector target. The first phase aims at operating the detector throughout LHC Run 3 to collect a total of 290 fb−1. The experiment was recently installed in the TI18 tunnel at CERN and has seen its first data. A new era of collider neutrino physics is just starting.

Speaker: Prof. Kang Young Lee (Gyeongsang National University)

2023.06.12.PPC2023_kylee.pdf

2023.06.12.PPC2023_kylee.pptx

14:20 Sensitivity to Secret Neutrino Interaction at Tau Neutrino Experiments

I will discuss the potential of future tau neutrino experiments, including the Liquid Argon detector DUNE atmospheric data, the Forward Liquid Argon Experiment (FLArE100) detector at the Forward Physics Facility (FPF), and emulsion detector experiments such as SND@LHC, FASER$\nu$2, and SND@SHiP, to search for a hidden interaction between neutrinos mediated by a new light sub-GeV gauge boson, $Z^\prime$, and the coupling $g_{\alpha \beta }$. I will explain how these experiments have the capability to significantly enhance the current constraints on $g_{\alpha \beta }$ for the $1~{\rm MeV}< M_{Z^\prime}< 500~{\rm MeV}$ mass range, as well as for $M_{Z^\prime}<{\rm few}~{\rm keV}$, due to their high energy and ability to detect $\tau$ neutrinos.
I will discuss the crucial role of DUNE atmospheric data in the search for hidden neutrino interactions because of its excellent detection capabilities for tau neutrinos. Specifically, I will represent that DUNE atmospheric data can set the most stringent constraint on $g_{\alpha \beta }$ and improve the current constraint by two orders of magnitude.

Speaker: Dr Meshkat Rajaee (JBNU)

PPC2023Meshkat.pdf

14:40 JUNO: Status and Prospects

The Jiangmen Underground Neutrino Observatory (JUNO) will be a 20-kiloton liquid scintillator detector, currently under construction in southern China. JUNO will be instrumented with close to 18,000 20-inch photomultiplier tubes (PMTs) and 26,000 3-inch PMTs, possessing the highest photocathode coverage of any kiloton-scale liquid scintillator or Cherenkov detector to date. JUNO aims to use its first-rate size, energy resolution and low background levels to deploy a broad physics programme, measuring neutrino energies from 10s of keV to 10s of GeV. JUNO’s primary physics goal is to resolve the fine structure due to oscillations in the nuclear reactor antineutrino energy spectrum, in order to determine the neutrino mass hierarchy and measure several oscillation parameters to a sub-percent precision. In this talk, I will discuss the status of the JUNO experiment as well as its physics potential. I will review the experiment’s program with a number of terrestrial and astrophysical neutrino sources such as solar neutrinos, supernovae, geoneutrinos, atmospherics, along with searches for rare BSM decays.

Speaker: Iwan Morton-Blake (Tsung-Dao Lee Institute / Shanghai Jiao Tong University)

JUNO_Status&Prospects_PPC2023.pdf

JUNO_Status&Prospects_PPC2023.pptx

15:00 Solar neutrinos and future experiments

While the LMA-MSW solution has been successful in explaining the flavor conversion of solar neutrinos, there exist tensions between the observed data and theoretical predictions. To address these discrepancies, the possibility of new physics theories such as Non-Standard neutrino Interaction (NSI) and the presence of a sterile neutrino are explored.
I will discuss the sensitivity of future solar neutrinos such as Yemilab to determination of solar neutrino oscillation parameters. Moreover, I will explain how future solar and reactor neutrino experiments are expected to achieve sub-percent precision, allowing for greater sensitivity to Earth's tomography using the day-night asymmetry of solar neutrinos. In this talk I will discusses the sensitivity of future solar experiments the Earth tomography using day-night asymmetry of solar neutrinos and new physics such as NSI and super-light sterile neutrino scenarios.

Speaker: Dr Pouya Bakhti (JBNU)

presentation.pdf

16:00 → 16:30 Coffe & Break

16:30 → 18:30 Parallel: Astroparticle 1

Convener: Kensuke Akita (IBS-CTPU)

16:30 Solar vectors at the JUNO detector

I will describe the sensitivity reach of the next-generation large underground neutrino oscillation experiment Jiangmen Underground Neutrino Observatory (JUNO) in order to detect the $5.49$ MeV hidden vector flux produced in the $p\left(d,^3\!{\rm He}\right)\gamma^\prime$ nuclear reaction. Based on the JUNO’s energy resolution capability and detector volume, we perform a systematic analysis and forecast the sensitivity, considering mass vs coupling strength in a model-independent and phenomenological way.

Speaker: Dr Seokhoon Yun (University of Padova & INFN Padova)

PPC2023_S.Yun_12.06.23.pdf

16:50 Exploration of Primordial Black Holes and Axion-Like Particles through a novel decay model on cosmological scale

Primordial black holes (PBHs) have been proposed as potential dark matter candidates and viable sources of axion-like particles (ALPs). Since ALPs primarily decay into photons, this process enables the detection of enhanced photon spectra with sensitive detectors. In this study, we develop a novel methodology for estimating photon spectra by considering significant redshift effects and time-dependent decay rates, defining time-varying decay processes on a cosmological scale. Furthermore, we rigorously compute the photon spectrum resulting from decaying ALPs, taking into account the Lorentz boost effect. Our analysis delineates additional photon spectra arising from photon emissions from PBHs and time-varying decay of ALPs, comparing them with the sensitivity of e-ASTROGAM, a future gamma-ray detector. This approach provides a new means to constrain parameters of PBH and ALP.

Speaker: Tae-Geun Kim (Yonsei University)

20230612_PPC2023_tgkim.pdf

17:10 Dark Matter Contributions to the Galactic Center 511keV Gamma-ray Line: Insights from Primordial Black Holes and Beyond-the-Standard-Model Particles.

The SPI/INTEGRAL observations reveal a remarkable 511keV gamma-ray line in the Galactic center region. However, astrophysical sources solely have not explained the 511keV emission from the positron annihilation. In this study, we explore the role of dark matter (DM) in shedding light on the line's morphology. We postulate that primordial black holes (PBHs), a compelling candidate for DM, emit not only standard model (SM) particles but also bosonic beyond-the-standard-model (BSM) particles, namely the spin-1 dark photon and spin-0 axion-like-particle (ALP), through Hawking radiation. We contend that the decay of these particles leads to the formation of positronium, which subsequently emits the 511 keV gamma-ray line. The results are based on meticulous numerical calculations that account for the Lorentz boost effect in the decay process and are fitted to the observational data. Consequently, we offer constraints on the abundance of PBH and characteristics of BSM particls from the morphology of 511keV line.

Speaker: Yeji Park (Yonsei Univ.)

PPC2023_yeji.pdf

17:30 WIMPy baryogenesis with Primordial Black Hole

We propose a model of baryogenesis achieved by the annihilation of non-thermally produced WIMPs from Primordial Black Hole (PBH). Dark Matter (DM) particles can be produced by PBH evaporation and consequently re-annihilate into lighter particles even after thermal freeze-out. The re-annihilation of DM provides the observed baryon asymmetry and the correct relic abundance of DM depending on the PBH evaporation temperature.

Speaker: Erdenebulgan Lkhagvadorj (Sungkyunkwan University)

PPC2023_EB.pdf

17:50 Improved white dwarves constraints on inelastic dark matter and Left–Right Symmetric Models

Weakly Interacting Massive Particles (WIMPs) can be captured in compact stars such as white dwarves (WDs) located in a dark matter(DM)-rich environment, leading to an increase in the star luminosity through their annihilation process. N-body simulations suggest that the core of the M4 globular cluster (where plenty of WDs are observed) is rich of dark matter. Assuming this is the case, I will show that when the WIMP interacts with the nuclear targets within the WD through inelastic scattering, and its mass exceeds a few tens GeV, the data on low-temperature large-mass WDs in M4 can probe values of the inelastic mass splitting as large as 40 MeV, if the recent improvement in the calculation of the WD equation of state is used. Such a value largely exceeds those ensuing from direct detection and from solar neutrino searches. We apply such improved constraint to the specific DM scenario of a self-conjugate bi-doublet in the Left-Right Symmetric Model (LRSM). I will show that bounds from WDs significantly reduce the cosmologically viable parameter space of such scenario.

Speaker: Dr Arpan Kar (Center for Quantum Spacetime (CQUeST), Sogang University)

ArpanKar_WD_LRSM.pdf

18:10 Cogenesis of visible and dark sector asymmetry in a minimal seesaw framework

We present a unified framework accommodating the matter-anti-matter asymmetry of the Universe as well as asymmetric dark matter. The out-of-equilibrium decay of the heavier right-handed neutrinos are shown to generate both, the matter anti-matter asymmetry of the visible sector
through leptogenesis, as well as dark matter bearing a concomitant stamp of asymmetry. The asymmetry in the dark sector is manifested in the predominance of one parity of the heavy neutrinos in the comoving frame, determined by the choice of a sign in the lagrangian. The model allows
for a wide range of dark matter masses, from MeV to TeV scale, and is also able to provide for the active neutrino masses through Type-I seesaw mechanism. Thus, the model explains the lepton asymmetry, dark matter bundance, and neutrino masses all in a next-to-minimal framework.

Speaker: Lekhika Malhotra (Indian Institute of Technology Bombay)

16:30 → 18:10 Parallel: Dark Matter 2

Convener: Jia Liu (Peking University)

16:30 Search for axion dark matter at IBS-CAPP

The axion is a well-motivated hypothetical particle resulting from the Peccei-Quinn mechanism, which is an elegant solution to the strong $CP$ problem of quantum chromodynamics. Because of its nature, abundance in the Universe, and extremely weak coupling, it is also considered a promising candidate for dark matter, another big mystery of the Universe. Among many experimental techniques to detect the axion in the galactic halo, the technique using a microwave resonant cavity, the axion haloscope, is the most widely used one. The Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science (IBS) has been searching for the axion mainly based on this approach. This talk presents the recent results of the axion search experiments in IBS-CAPP. Technical developments and plans to improve experimental sensitivity are also discussed.

Speaker: Junu Jeong (IBS-CAPP)

Junu_PPC2023-2.pdf

16:50 The first high-temperature superconducting cavities for axion dark matter search.

Superconducting radiofrequency (SRF) technology has played an essential role in advancing precision measurements in particle physics experiments, over the past decades, and is expected to be so in the search for dark matter axions. The axion haloscope requires high quality (Q) factor superconducting cavities immersed in multi-tesla magnetic fields for sensitive searches, which can be achieved using high-temperature superconducting (HTS) materials. Biaxially-textured rare-earth barium copper oxide (ReBCO) tapes, possessing strong vortex pinning capabilities in high magnetic fields, serve as an optimal material choice for realizing high Q cavities. The Center for Axion and Precision Physics Research has successfully demonstrated the technology by fabricating several cavities using commercially available ReBCO tapes. In this talk, we present the progress in next-generation cavities over the initial prototype. We detail the development of a large-volume GdBCO-tape cavity and two EuBCO-tape cavities, achieving Q factors of half-million, 3.5 million, and 13 million, respectively, at an 8 T magnetic field. These advancements have resulted in two-orders-of-magnitude improvement in Q factors compared to traditional copper cavities used in axion haloscopes, highlighting a major breakthrough in the field. Moreover, we discuss the first results of an axion dark matter search employing an HTS cavity with frequency tuning achieved by a sapphire rod. The experiment exhibited an order-of-magnitude increase in scanning speed compared to prior laboratory conditions.

Speaker: Danho Ahn (IBS/CAPP)

2023_June_PPC_DanhoAhn_v4.pdf

17:10 Detecting Dark Matter Induced Power in Quantum Devices

Quantum devices with ultrahigh sensitivities are being designed for various purposes ranging from developing quantum computers to building powerful telescopes. Typically, they use the sharp transition between superconducting and normal states of matter to detect small energy deposition. Such devices have also been used in direct detection experiments for light dark matter. I will talk about a new way of looking for dark matter signals using power measurements in these devices. I will describe how new constraints are set in the mass range 1 MeV to 10 GeV for galactic halo dark matter, as well as for thermalized dark matter near the Earth’s surface that can arise in strongly interacting models.

Speaker: Anirban Das (Seoul National University)

PPC 2023.pdf

17:30 Superfluid Optomechanics for dark matter direct detection

The direct detection of light (sub-MeV) dark matter presents a significant challenge due to the need for sub-eV energy thresholds. I will discuss a new proposal to use a superfluid helium optomechanical cavity to search for dark matter in the keV mass range. In this regime, dark matter scattering excites a single phonon in the superfluid helium target. Optomechanical systems have demonstrated sensitivity to individual phonons with meV energies, making them ideally suited to the detection of light dark matter.

Speaker: Dr Peter Cox (The University of Melbourne)

PeterCox_PPC2023.pdf

17:50 Search for sub-millicharged particles at J-PARC

Electric charge quantization is a long-standing question in particle physics. While fractionally charged particles (millicharged particles hereafter) have typically been thought to preclude the possibility of Grand Unified Theories (GUTs), well-motivated dark-sector models have been proposed to predict the existence of millicharged particles while preserving the possibility for unification. Such models can contain a rich internal structure, providing candidate particles for dark matter. A number of experiments have searched for millicharged particles ($\chi$s), but in the parameter space of the charge ($𝑄$) and mass ($m_\chi$), the region of $𝑚_\chi>0.1$ GeV/$\rm{c}^2$ and $𝑄<10^{−3}$𝑒 is largely unexplored.

SUB-Millicharge ExperimenT (SUBMET) has been proposed to search for sub-millicharged particles using 30 GeV proton fixed-target collisions at J-PARC. The detector is composed of two layers of stacked scintillator bars and PMTs, and is proposed to be installed 280 m from the target. The main background is expected to be a random coincidence between the two layers due to dark counts in PMTs and the radiation from the surrounding materials, which can be reduced significantly using the timing of the proton beam. With $\rm{N}_{\rm{POT}}=5\times 10^{21}$, the experiment provides sensitivity to $\chi$s with the charge down to $8\times 10^{−5}𝑒$ in $𝑚_\chi<0.2$ GeV/$\rm{c}^2$ and $10^{−3}𝑒$ in $𝑚_\chi>1.6$ GeV/$\rm{c}^2$. This is the regime largely uncovered by the previous experiments.

Speaker: Mr Changhyun Seo (Korea University)

2023_June_PPC_SUBMET.pdf

16:30 → 18:10 Parallel: Neutrino 2

Convener: Pouya Bakhti (JBNU)

16:30 The LEGEND experiment to search for neutrinoless double beta decay

The observation of a hypothesized, extremely rare process, neutrinoless double beta decay ($0\nu\beta\beta$), would demonstrate that neutrinos are Majorana particles, i.e., their own antiparticles, and would establish lepton-number violation. Furthermore, it would provide hints of the neutrino absolute mass scale and the neutrino mass ordering, as well as information about the matter-antimatter imbalance of the Universe.

LEGEND (Large Enriched Germanium Experiment for Neutrinoless double beta Decay) will search for $0\nu\beta\beta$ with high-purity germanium detectors enriched in $^{76}\text{Ge}$ and operated in a liquid-argon cryostat, which serves as a coolant, a passive shield, and an active veto system. The first phase of the experiment (LEGEND-200) will deploy around 200 kg of germanium diodes and reach a discovery sensitivity of $> 10^{27}$y ($3\sigma$) for the half-life of $0\nu\beta\beta$ with an experimental live-time of five years. The first physics run has started with an initial 142 kg of germanium diodes (101 detectors). The other 50 kg of detectors will be characterized and installed in late 2023 to reach its full mass. The second phase of the experiment (LEGEND-1000) aims to improve the discovery sensitivity by another order of magnitude with 1 tonne of large-mass, high-purity, enriched germanium detectors operated for ten years. By reducing the background levels with several hardware approaches and improved analysis techniques, as well as operating with detectors of the best energy resolution in the field, LEGEND will perform a quasi-background-free search, where an unambiguous signature can be distinguished at the $0\nu\beta\beta$ decay $Q$-value of 2039 keV.

Speaker: Pin-Jung Chiu (University of Zurich)

2023-06-12-Chiu-PPC2023-Daejeon.pdf

16:50 AMoRE

The absolute mass scale of neutrinos and whether neutrinos are Majorana or Dirac particles can be determined by the detection of neutrinoless double beta decay (0vββ). Key parameters for the experimental sensitivity are the energy resolution and the background level at the region of interest. AMoRE searches for 0vββ using molybdenum-100 enriched scintillation bolometer crystals in a cryogenic detector system at deep underground. Detector performances and efforts to reduce the background have been demonstrated in the pilot and the first stage of AMoRE conducted in the Yangyang Underground Laboratory. The next and main stage of AMoRE, AMoRE-II, is about to start its operation in the newly built Yemi Underground Laboratory. Using crystals made from about 100 kg of molybdenum-100 isotope for at least 5 years, we expect to have the discovery sensitivity for the 0νββ half-life at 5$\times10^{26}$ years.

Speaker: Yoomin Oh (Center for Underground Physics, Institute for Basic Science)

yoomin_AMoRE_ppc2023.pdf

17:10 CDEX-300v: neutrinoless double beta decay experiment based on Ge-76

Neutrinoless double beta decay (0νββ) is one outstanding problem that has strong links with several important topics including confirming whether the neutrino has Dirac or Majorana character and whether lepton number is conserved. Beside direct searches of Dark Matter (DM), the China Dark Matter Experiment (CDEX) collaboration proposed and is pushing forward to build the CDEX-300ν experiment to search 0νββ of 76Ge isotope based on germanium detector. CDEX-300ν project will includes a 76Ge-enriched germanium array detector system with total mass of 300 kg and a liquid argon active shielding system. The liquid argon tank is located into a liquid nitrogen tank with a volume of 1725 m³ for cooling down and further decreasing the ambient radioactive backgrounds. More details of CDEX-300ν will be introduced in this talk.

Speaker: Dr Li Wang (Beijing Normal University)

17:30 Neutrino Elastic-scattering Observation with NaI(Tl)(NEON)

The NEON experiment aims to observe coherent elastic neutrino-nucleus scattering (CEvNS) using reactor anti-electron neutrinos with NaI(Tl) crystal detectors at the Hanbit nuclear power plant in Yeonggwang, South Korea. Although CEvNS has been observed by the COHERENT collaboration using a spallation neutron source, the same process with reactor neutrinos has not yet been observed. The NEON detector consists of a 16.5 kg NaI(Tl) target mass installed 24 meters from the reactor core. The probability of CEvNS observation relies on detector performance, such as background level and low-energy threshold. The light yield of the detector is approximately 23 NPE/keV, which is about 50% higher than the previous detector due to R&D. The background level of roughly 6 counts/day/kg/keV and a below 0.6 keV energy threshold have already been achieved. Further analysis is ongoing to optimize the low-energy threshold through waveform simulation, which is used as a scintillating signal sample for Boosted Decision Trees (BDT) training. Current physics data were collected during both reactor shutdown (5 months) and reactor operation (ongoing for approximately 5 months). This presentation will provide an overview and current status of the NEON experiment.

Speaker: Jaejin Choi (Seoul National University)

2023PPC_NEON.pdf

17:50 Latest result of JSNS2 and status of JSNS2-II

The primary purpose of the JSNS2 (J-PARC Sterile Neutrino Search at the J-PARC Spallation Neutron Source) experiment is to search for neutrino oscillations over a short 24 m baseline with Δm2 near 1 eV square. Physics run data have been acquired in 2021/2022, corresponding to 23 % of approved Proton On Target (POT) by J-PARC. We also have a plan for using another detector as the 2nd phase of the experiment (JSNS2-II). The 2nd detector will be installed on the far side, 48 m from the target, to observe neutrinos' more apparent oscillation behavior. It will be filled with 32 tons of Gd-LS, and designed with a longer baseline than the near-side detector. Combined analysis using both detectors is expected to reduce systematic uncertainties and provide significantly better sensitivity, especially in the low Δm2 region. In this presentation, we will summarize the latest results of JSNS2, and the status of JSNS2-II.

Speaker: Dr Ryeonggyoon Park (Kyungpook National University)

230612_Latest results of JSNS2 and status of JSNS2-II.pdf

18:30 → 20:30 Reception

Tuesday, 13 June

09:00 → 10:30 Plenary: Neutrino 1

Convener: Seon-Hee Seo (IBS)

09:00 Long-baseline Neutrino Experiments

Speaker: Prof. Hirohisa Tanaka (SLAC)

PPC2023_Tanaka.pdf

09:30 Short-baseline Neutrino Experiments

Short Baseline Neutrino Program (SBN) at Fermilab aims to confirm or refute the anomalies observed at LSND and MiniBooNE in short baseline neutrino oscillation, which can be interpreted as existence of an additional state of neutrinos with eV-scale, also known as a "sterile neutrino." The technology of liquid-argon time-projection chambers (LArTPCs) is chosen
for all the SBN experiments, allowing separation of electrons from photons and thereby precisely measuring the probability of neutrino oscillation.
The SBN experiments also provide extensive measurements of neutrino-Ar interaction cross sections, and searches for physics beyond the Standard Model.

Operating in 2015-2022, MicroBooNE, Phase I SBN, has tested hypotheses of MiniBooNE anomaly with half of its collected data. The far detector of Phase II SBN, ICARUS, started taking data in 2022 and expects to have the first physics preliminary results this year, while the near detector, SBND, is rapidly progressing on its installation.

The other short baseline neutrino experiments receiving neutrinos produced by pions decay-at-rest, such as JSNS^2 and COHERENT,
also will provide complementary searches for sterile neutrinos via
oscillation measurements.

Speaker: Dr Yun-Tse Tsai (SLAC)

PPC_20230613.pdf

10:00 Sterile Neutrino Experiments

Speaker: Yoomin Oh (Center for Underground Physics, Institute for Basic Science)

yoomin_v4exp_ppc2023.pdf

10:30 → 11:00 Coffee & Break

11:00 → 12:30 Plenary: Dark Matter 1

Convener: Dr SungWoo Youn (IBS-CAPP)

11:00 Indirect Detection of Dark Matter

Speaker: Shunsaku Horiuchi (Virginia Tech)

horiuchi_PPC2023_PDF.pdf

11:30 Cosmological Origins of Axion Dark Matter

Speaker: Raymond Co (University of Minnesota)

Cosmological Origins of Axion Dark Matter.pdf

12:00 Axion Experiments

Speaker: Prof. Yannis Semertzidis (IBS-CAPP/KAIST)

12:30 → 14:00 Lunch

14:00 → 16:00 Parallel: Astroparticle 2

Convener: Tae Hyun Jung (IBS CTPU)

14:00 Possible origins of > 10 TeV photons detected from GRB 221009A

Gamma-Ray Burst (GRB) 221009A was once in a century event detected from radio to very high-energy (VHE) gamma rays. It was the first time that $> 10$ TeV gamma rays were detected from a GRB. Even though GRB 221009A was a relatively nearby event at redshift 0.15, detection of a 18 TeV photon by the LHAASO detector and of a 251 TeV photon by the Carpet-2 detector challenge conventional radiation mechanisms of a GRB and/or propagation of VHE gamma rays in the cosmic radiation backgrounds. In particular, gamma-ray flux at 18 TeV is expected to be attenuated by a factor $\sim 4.5\times 10^{-5}$ and more severely at 251 TeV due to $\gamma\gamma\to e^\pm$ pair production by interacting with the photons of the extragalactic background light (EBL). In this presentation, I will discuss possible explanation of the detection of 18 TeV photon due to ultrahigh-energy cosmic rays originating from GRB 221009A and interacting while propagating along the line-of-sight [1], and the detection of 251 TeV photon due to violation of Lorentz invariance [2].

[1] S. Das and S. Razzaque, "Ultrahigh-energy cosmic-ray signature in GRB 221009A," Astron. Astrophys. 670, L12 (2023) [arXiv:2210.13349 [astro-ph.HE]].

[2] J. D. Finke and S. Razzaque, "Possible Evidence for Lorentz Invariance Violation in Gamma-Ray Burst 221009A," Astrophys. J. Lett. 942, no.1, L21 (2023) [arXiv:2210.11261 [astro-ph.HE]].

Speaker: Soebur Razzaque (University of Johannesburg Centre for Astro-Particle Physics)

S_Razzaque_PPC2023_Daejeon_Korea.pptx

14:20 Primordial Black Holes from Scalar Fields and their Novel Manifestations

Primordial black holes (PBHs) from the early Universe constitute an attractive non-particle dark matter (DM) candidate. I will present several generic mechanisms of PBH formation based on scalar fields, highlighting how astrophysical signatures of PBHs can help distinguish them. Intriguingly, detected microlensing candidate events by Subaru Hyper Suprime-Cam could be the first hints of PBHs associated with yet unexplored regimes of the fundamental QCD strong force or bubble multiverse. I will further highlight connections of PBHs with various astronomical puzzles and signatures, charting prospects for discovery.

Speaker: Volodymyr Takhistov (QUP, KEK & Kavli IPMU)

PPC2023_PBH_Takhistov.pdf

14:40 Signatures of a Higher Temperature QCD Transition in the Early Universe

Beyond Standard Model physics could increase the temperature the QCD phase transition and transform it to a first order phase transition. Primordial black hole production is enhanced during first order phase transitions due to a softening of the equation of state and could result in significant abundances without a corresponding peak in the inflationary power spectrum. In contrast to the SM QCD transition, PBH produced at higher temperatures would have smaller masses and could be a dark matter candidate within the asteroid mass window or match the proposed Hyper Suprime-Cam microlensing signal. Furthermore, the curvature perturbations that generate these PBH populations can account for the claimed NANOGrav gravitational wave signal.

Speaker: Philip Lu (Seoul National University)

High Temperature QCD PBH.pdf

15:00 Evolution of magnetic fields in cosmic string wakes.

We study the evolution of magnetic fields in cosmic string wakes in a plasma with a low resistivity. The initial magnetic field in the wake is modelled on the magnetic fields that are generated by the motion of particles around cosmic strings. The plasma is characterized by a high beta value. We find multiple shock like structures developing in the wake of the string. We study the detailed structure of the shocks formed and the evolution of the magnetic field in the shock using a 2-D magnetohydrodynamic simulation. As expected, the development of the magnetic field does not depend on the $\beta$ value. Our results show that instead of a single uniform shock forming behind the cosmic string we have multiple shocks forming at short time intervals behind the string. The presence of multiple shocks will definitely affect the observational signatures of cosmic string wakes as these signatures depend upon the temperature fluctuations generated by the shock. We also find that as the shock moves away, the residual magnetic field left behind reconnects and dissipates rapidly. The magnetic field around the string is thus very localized. We find that magnetic field reconnections take place in cosmic string wakes. This leads to the decrease of the magnetic field in the post shock region.

Speaker: Soumen Nayak (School of Physics, University of Hyderabad)

Soumen PPC.pdf

14:00 → 16:00 Parallel: Cosmology 2

Convener: Seokhoon Yun (University of Padova)

14:00 Gravitational waves and UHECRs in a supersymmetric local U(1) B-L model

We propose a minimal supersymmetric local U(1) B-L model. A stochastic gravitational wave background and ultrahigh-energy cosmic rays are expected, and can be probed in the near future experiments.

Speaker: Wan-Il Park (Jeonbuk National University)

20230613-PPC2023-final-wipark.pdf

14:20 A flashing beacon in axion inflation: recurring bursts of gravitational waves in the strong backreaction regime

The coupling between a pseudo-scalar inflaton and a gauge field leads to an amount of additional density perturbations and gravitational waves (GWs) that is strongly sensitive to the inflaton speed. This naturally results in enhanced GWs at (relatively) small scales that exited the horizon well after the CMB ones, and that can be probed by a variety of GW observatories (from pulsar timing arrays, to astrometry, to space-borne and ground-based interferometers). This production occurs in a regime in which the gauge field significantly backreacts on the inflaton motion. Contrary to earlier assumptions, it has been recently shown that this regime is characterized by an oscillatory behavior of the inflaton speed, with a period of ~O(5) e-folds. Bursts of GWs are produced at the maxima of the speed, imprinting nearly periodic bumps in the frequency-dependent spectrum of GWs produced during inflation. This can potentially generate correlated peaks appearing in the same or in different GWs experiments.

Speaker: Alexandros Papageorgiou (IBS-CTPU)

A flashing beacon_Papageorgiou.key

14:40 Small Scale Structure of Multi-component Dark Matter

We present distinctive properties of multi-component dark matter from the structure formation of halos on small scale. We solve linear Einstein-Boltzmann equations, and show how density contrasts and the power spectrum change. To incorporate non-linear effects, we use the above result to perform N-body simulations, and discuss various phenomenological aspects of the model.

Speaker: Jeong Han Kim (Chungbuk National University)

PPC_2023.pdf

15:00 Joint reconstructions of growth and expansion histories with minimal assumptions

Using data from upcoming (Stage-IV) cosmological surveys, we jointly reconstruct the Universe’s growth and expansion histories using forward modeling and Gaussian Processes. Our approach only relies on a few reasonable assumptions, namely:

• A (flat) Friedmann-Lemaître-Robertson-Walker metric,
• An Einstein De Sitter (matter-dominated) Universe at high redshift. 


We forecast the upcoming surveys’ potential to accurately reconstruct the Dark Energy (DE) evolution and thus detect any possible deviation from a cosmological constant. We generate mock data for various alternative DE models and illustrate how our method captures the correct DE behavior in all cases — being capable of distinguishing them from $\Lambda$ at more than 95% C.L.
Finally, we extend our methodology to include possible deviations from General Relativity (GR) at low-$z$, by simultaneously reconstructing the phenomenological function $G_{\rm eff}(z)$ governing the growth of (dust-like) matter density perturbations.

Speaker: Rodrigo Calderon (Korea Astronomy and Space Science Institute (KASI))

IBS-PPC-2023.pdf

15:20 Revisiting the gravitational lensing analysis of the Bullet Cluster using radio waves

Gravitational lensing analysis in the Bullet Cluster suggested convincingly in favor of the existence of dark matter. However, it was performed without the knowledge of the original orientation of each galaxy before gravitational lensing. Thankfully, we can now measure the original orientation from the polarization direction of radio waves emitted from each galaxy. In this context, Francfort et al. derived a formula that can utilize the information about the original orientation of each galaxy to obtain what is called "shear." However, we show that their formula for shear is actually a formula for "reduced shear" if we consider the size change of galactic images which they did not. As the previous gravitational lensing analysis in the Bullet Cluster used reduced shear, we suggest applying our improved formula directly for the re-analysis once we obtain the polarization direction of radio waves in the future.

Speaker: Youngsub Yoon

bulletclusterPPC2023.pdf

14:00 → 16:00 Parallel: Dark Matter 3

Convener: Meshkat Rajaee (JBNU)

14:00 Boosted dark matter searches with Super-Kamiokande

Speaker: Nadège Iovine (IBS - CUP)

PPC2023_BDMSearch_SuperK_v3.pdf

14:20 An Analytic Approach to Light Dark Matter Propagation

Although searches for GeV-scale WIMPs are sensitive to very small cross sections, constraints on sub-GeV dark matter are significantly weaker, and largely constrain moderately- or strongly-interacting dark matter. But if dark matter interacts too strongly with nuclei, it could be slowed to undetectable speeds in Earth’s crust or atmosphere before reaching a detector. For sub-GeV dark matter, approximations used to model the attenuation of heavier dark matter fail, necessitating the use of computationally expensive simulations. I present a new, analytic approximation for modeling attenuation of light dark matter in the Earth. I show that our approach agrees well with Monte Carlo results, and can be much faster at large cross sections.

Speaker: Christopher Cappiello (Queen's University)

Cappiello PPC 2023-2.pptx

14:40 Constraints on cosmic-ray boosted dark matter from the XENONnT experiment

Sub-MeV cold dark matter (DM) particles are unable to produce electronic recoil in the XENONnT experiment above the detector threshold. The mechanism of boosted dark matter (BDM) scenario comes into picture to constrain the parameter space of such low mass dark matter from direct detection experiments. We consider the effect of the leading components of cosmic rays to boost the cold DM. To present a concrete example, we choose to work on a model consisting of a Dirac fermion $\chi$ with a new $U(1)′$ gauge symmetry while the new gauge boson A′ being kinetically mixed with the standard model $U(1)_Y$ gauge boson. We found that the energy dependence of the cross section plays a crucial role in improving the constraints. We also considered the earth shielding effect on BDM in losing energy while travelling to the underground detector through the earth. We present an approximate analytical estimate for this purpose.

Speaker: Atanu Guha (Chungnam National University)

presentation_Atanu.pdf

15:00 Upscattering of light dark matter by stellar neutrinos and cosmic rays

A novel mechanism of boosting dark matter by cosmic neutrinos is proposed. The new mechanism is so significant that the arriving flux of dark matter in the mass window from keV to GeV on Earth can be enhanced by two to four orders of magnitude compared to one only by cosmic electrons. Including both galactic and extragalactic origins of boosted dark matter upscattered by stellar neutrinos with a reasonable galaxy profiles for massive halos, we firstly derive conservative but still stringent bounds and future sensitivity limits for such cosmic-neutrino-boosted dark matter (vBDM) from advanced underground experiments such as XENONnT and JUNO.

Speaker: Yongsoo Jho (Weizmann Institute of Science)

230613_ppc2023_yjho.pdf

15:20 Assessing the Impact of Hydrogen Absorption on the Characteristics of the Galactic Center Excess

We present a new reconstruction of the distribution of atomic hydrogen in the inner Galaxy based on explicit radiation-transport modelling of line and continuum emission and a gas-flow model in the barred Galaxy that provides distance resolution for lines of sight toward the Galactic Center. The main benefits of the new gas model are a) the ability to reproduce the negative line signals seen with the HI4PI survey and b) the accounting for gas that primarily manifests itself through absorption. We apply the new model of Galactic atomic hydrogen to an analysis of the diffuse gamma-ray emission from the inner Galaxy, for which an excess at a few GeV was reported that might be related to dark matter. We find with high significance an improved fit to the diffuse gamma-ray emission observed with the Fermi-LAT if our new HI model is used to estimate the cosmic-ray-induced diffuse gamma-ray emission. The fit still requires a nuclear bulge at high significance. Once this is included, there is no evidence for a dark-matter signal, be it cuspy or cored. But an additional so-called boxy bulge is still favoured by the data. This finding is robust under the variation of various parameters, for example, the excitation temperature of atomic hydrogen and several tests for systematic issues.

Speaker: Chris Gordon (University of Canterbury (NZ))

pdf file for talk

powerpoint file for talk

15:40 Dark matter constraints from 14 years of Fermi data

I present constraints on various dark matter models from the analysis of 14 years of Fermi data, including thermal higgsino dark matter. This scenario is well-motivated from supersymmetric extension of the Standard Model. We analyze Fermi data near the Galactic Center in search for continuum gamma-ray emission that may occur from the annihilation of higgsino DM through the W+W- and Z Z final states. While we set the strongest constraint to-date on higgsino-like DM, we also find a modest excess that we show could be consistent with the expected higgsino signal. In addition, we consider the scenario in which DM may annihilate or decay to photons, producing monochromatic gamma-rays. We search for such signals in Fermi data, and present constraints as strong as $<\sigma v > \lesssim 6 \times 10^{-30}$ cm^3/s for two-to-two annihilations and $\tau \gtrsim 10^{30}$ s for one-to-two decays, representing leading sensitivity between 10 GeV and ~ 500 GeV. These constraints place non-trivial restrictions on models that address the Fermi Galactic Center Excess; for example, we disfavor Higgs portal explanations of the excess.

Speaker: Ms Yujin Park (University of California, Berkeley)

PPC2023-Fermi.pdf

16:00 → 16:30 Coffee & Break

16:30 → 18:50 Parallel: Collider Physics

Convener: Sung Hak Lim (Rutgers University)

16:30 Machine Learning for collider physics

In this talk, I will explain how we can utilize Machine Learning techniques for collider phenomenology, especially to study various kinematics.

Speaker: Myeonghun Park (Seoul National University of Science and Technology)

PARC.pdf

16:50 Multi-photon decays of the Higgs boson at the LHC

Many new physics scenarios predict multi-photon Higgs resonances. One such scenario is the dark axion portal. The primary decay chain that we study is the Higgs to dark photon ($\gamma_D$) pairs that subsequently decay into a photon and an axion-like particle ($a$). The axion-like particles then decay into photon pairs. Hence, the signal is a six-photon Higgs decay: $h\rightarrow \gamma_D\,\gamma_D\rightarrow 2\,\gamma 2\,a\rightarrow 6\gamma$. However, depending on the relevant kinematics, the photons can become well-collimated and appear as photon-jets (multiple photons that appear as a single photon in the detector) or $\xi$-jets (non-isolated multi-photon signals that do not pass the isolation criterion). These effects cause the true six-photon resonance to appear as other multi-photon signals, e.g., four or two photons. The four photon signal is particularly interesting. These events mainly occur when the photons from the axion are collimated into a photon jet. The apparent decay of the dark photon is then $\gamma_D\rightarrow \gamma a\rightarrow \gamma+\gamma$-jet. This decay seems to violate the Landau-Yang Theorem at the detector level since the dark photon appears to decay into a pair of massless photons. We explore and examine the multi-photon signals that could appear at the Large Hadron Collider (LHC). The mass regions where two, four, and six-photon resonances dominate are determined. Some additional signal categories involving $\xi$-jets are considered. All of these multi-photon signals provide excellent footing to explore new physics at the LHC and beyond.

Speaker: Samuel Lane (KAIST)

Lane_PPC_2023.pdf

17:10 Search for heavy charged gauge bosons with high pT lepton in pp collisions at CMS

Many Beyond the Standard Models (BSMs), e.g., extended standard model, extra dimensions, supersymmetric model, compositeness, extended Higgs sectors, are expected to manifest new heavy charged gauge bosons at TeV scale in the final states with one lepton and a neutrino (missing transverse momentum, MET). This talk presents searches in pp collisions at CMS for new phenomena in the final states containing a high-pT lepton (electron, muon, and tau) and MET, focusing on the recent results obtained using the full Run-2 (2016-2018) dataset collected at the LHC.

Speaker: Dr JeongEun Lee (Seoul National University)

PPC2023_LplusMETsearch_jeongeunLEE.pdf

17:30 Looking forward to photon-coupled long-lived particles at the LHC Forward Physics Facility

Many Dark Sector models contain photon-coupled long-lived particles. An outstanding example is an axion-like particle decaying into two photons. The forward physics detectors at the LHC, e.g., FASER, were shown to be particularly suitable for hunting ~sub-GeV ALPs thanks to numerous photons produced in pp collisions, which in turn are efficiently converted into ALPs by the Primakoff scattering. We consider a few of beyond the SM physics scenarios in which similar processes can occur. We find that FASER2 experiment will cover a significant part of the available parameter space for each of them. Moreover, we show that secondary production of LLPs can improve the coverage of parameter spaces towards the regime of smaller lifetimes.

Speaker: Krzysztof Jodlowski (IBS CTPU)

Looking_forward_to_photon_coupled_LLPs_final.key.pdf

17:50 New physics searches at future muon colliders

In this talk I will discuss the potential of muon colliders in finding new physics signals at muon colliders. I will briefly comment on the pros of muon colliders as compared to electron-positron colliders and hadron-hadron colliders. I will then discuss the dark-matter production at muon colliders in 54 production channels. Finally I will comment on the discovery potential for neutrino mass generation models taking the Zee-Babu model as an example.

Speaker: Dr Adil Jueid (CTPU-IBS)

main.pdf

18:10 Higher-order initial state radiation in $e^+e^-$ annihilation

The studies of high-energy physics processes at future high-luminosity electron-
positron colliders require very precise calculations of QED radiative corrections for construction of sufficiently accurate theoretical predictions of these processes. The bulk of effect is provided by higher-order radiative corrections enhanced by the so-called large
logarithm $L = \ln \left( \frac{\mu^2}{m^2_e} \right) $ which depends on the factorization energy scale $\mu >> m_e$.
Radiative corrections in the leading and next-to-leading logarithmic approximations can be analytically calculated within the QED parton distribution functions approach. To calculate higher-order corrections we solve QED evolution equations by iterations. We calculated radiative corrections to the cross-section of electron-positron annihilation up to $O(\alpha^3 L^2)$ using this method. The results are relevant for physical programs of future high-energy electron-positron colliders including searches for dark matter.

Speaker: Uliana Voznaya (JINR)

PPC-Voznaya.pdf

18:30 Quantum metric learning for jet analysis

Recently, quantum computing holds great promise in HEP analysis. Quantum metric learning is a self supervised learning method in which signal and background events are learned via a quantum repeated embedding that maximizes the distance between the different projected events onto the qubit. Quantum metric learning shows larger classification performance over the classical (contrastive) metric learning, e.g simCLR. Moreover, classical contrastive learning suffers from the collapse of the projection heads which degrade the classification performance in most of the classification analysis. Quantum metric learning with Hilbert-Schmidt distance overcomes the collapse problem.

Speaker: Dr Ahmed Hammad (Seoul Tech.)

16:30 → 18:30 Parallel: Dark Matter 4

Convener: Christopher Cappiello (Queen's University)

16:30 Neutrinos and Ultra Light Dark Matter

Ultra light boson is an attractive dark matter candidate whose classical wave nature implies various interesting phenomena. Considering its coupling to neutrinos in this talk, we discuss how the required dark matter population can be generated and/or its impact on the neutrino oscillations.

Speaker: Eung Jin Chun (KIAS)

230613-PPC-NuULDM.pdf

16:50 Constraints on dark matter-neutrino scattering with Milky-Way satellite observations and semi-analytical subhalo modeling for dark acoustic oscillations

The elastic scattering between dark matter (DM) and radiation can potentially explain small-scale observations that the cold dark matter faces as a challenge, as damping density fluctuations via dark acoustic oscillations in the early universe erases small-scale structure. We study a semi-analytical subhalo model for interacting dark matter with radiation, based on the extended Press-Schechter formalism and subhalos’ tidal evolution prescription. We also test the elastic scattering between DM and neutrinos using observations of Milky-Way satellites from the Dark Energy Survey and PanSTARRS1.

Speaker: Kensuke Akita (IBS-CTPU)

PPC2023_Akita.pdf

17:10 High-energy particle attenuation within dark matter spikes

In this talk, I will discuss the attenuation of high-energy particles in Active Galactic Nuclei (AGN), when they propagate through the dark matter spike around the central black hole and the halo of the host galaxy. First, based on 2209.06339, I will discuss new constraints on the dark matter-neutrino and dark matter-photon scattering cross sections obtained from the observation by IceCube of a few high-energy neutrino events from TXS 0506+056, and their coincident gamma-ray events. Finally, I will discuss new constraints on the dark matter-proton and dark matter-electron scattering cross section obtained with high-energy neutrino and gamma-ray observations from NGC 1068.

Speaker: Gonzalo Herrera (TUM, MPP)

Particle_attenuation_within_dark_matter_spikes__Daejeon_Herrera.pdf

17:30 Cored Dark Matter halos in the Cosmic Neutrino Background

We study the impact of the interaction between DM and the cosmic neutrino background on the evolution of galactic dark matter halos. The energy transfer from the neutrinos to the dark matter can heat the center of the galaxy and make it cored. This effect is efficient for the small galaxies such as the satellite galaxies of the Milky Way and we can put conservative constraint on the non-relativistic elastic scattering cross section as $\sigma_{\chi\nu} ≲ 10^{−31}~\text{cm}^2$ for 0.1 keV dark matter and 0.1 eV neutrino.

Speaker: Wonsub Cho (Sungkyunkwan University)

PPC_2023.pdf

17:50 Confronting Dark Matter with Dirac Neutrinos

We propose a Dirac neutrino portal dark matter scenario by minimally extending the particle content of the Standard Model (SM) with three right-handed neutrinos, a Dirac fermion dark matter candidate, and a complex scalar, all of which are singlets under the SM gauge group. symmetry $Z_4$ has been introduced for the stability of dark matter candidates and also to ensure the Dirac nature of light neutrinos at the same time. We studied both thermal and non-thermal dark matter scenarios and the possibility of probing such scenarios through the contribution to the effective relativistic degrees of freedom $\Delta{N_{\rm eff}}$. We also check the stringent constraints on the free-streaming length of such freeze-in DM from structure formation requirements. Such constraints can rule out DM mass all the way up to $\mathcal{O}$(100 keV).

Speaker: Dibyendu Nanda (Korea Institute for Advanced Study)

PPC23_Dnanda.pdf

18:10 Reviving the keV neutrino: a novel production mechanism for sterile neutrino dark matter

We propose a new production mechanism for keV sterile neutrino dark matter which does not rely on the oscillations between sterile and active neutrinos nor on the decay of additional heavier particles, and works without employing any new interactions for the sterile neutrinos beyond the standard Yukawa couplings. The dark matter neutrinos are instead produced out of thermal freeze-out, much like typical a WIMP. The challenge consists in balancing a large Yukawa coupling so that the sterile neutrinos thermalize in the early universe on the one hand, and a small enough Yukawa coupling such that they are stable on cosmological scales on the other. We solve this problem by implementing varying Yukawa couplings. We achieve this by using a three-sterile neutrino seesaw extension to the SM and embedding it in a Froggatt-Nielsen model with one single flavon. If the vev of the flavon changes during the electroweak phase transition, the effective Yukawa couplings of the fermions have different values before and after the phase transition, thus allowing for successful dark matter genesis. Additionally, the flavour structure and the origin of the light neutrino masses are explained by the interplay of the seesaw and Froggatt-Nielsen mechanisms. Other Implementations of the varying Yukawa couplings aside from the Froggatt-Nielsen framework are also explored.

Speaker: Carlos Jaramillo (Max-Planck-Institut fuer Kernphysik)

PPC_Carlos_Jaramillo_2023.pdf

16:30 → 18:50 Parallel: Gravitational Wave 1

Convener: William DeRocco (University of California, Santa Cruz)

16:30 Determining Inflaton Interactions via Gravitational Waves

It has been investigated to what extend one can constrain inflaton couplings to matter adopting future gravitational wave detectors. Various possible inflaton interactions have been considered. It turned out that in certain cases the proposed gravitational detector facilities would be sensitive the strength of the inflaton-matter couplings.

Speaker: Prof. Bohdan Grzadkowski (University of Warsaw)

PPC2023_Grzadkowski_4.pdf

16:50 Gravitational Wave Signatures of Reheating

We initiate a study of the gravitational wave signatures of a phase transition that occurs as the Universe's temperature increases during reheating. The gravitational wave signatures of a heating phase transition are different from those of a cooling phase transition and observation of them would allow us to probe reheating. In the lucky case that the gravitational wave signatures from both the heating and cooling phase transitions were observed, information about reheating could in principle be obtained utilizing the correlations between the two transitions. Frictional effects leading to a constant bubble wall speed in one case will instead accelerate the bubble wall, often into a runaway, in the other case. The efficiencies, strength of the phase transition and duration of the phase transitions will be similarly correlated in a reheating dependent manner.

Speaker: Jae Hyeok Chang (JHU/UMD)

Slides_Chang.pdf

17:10 Axion Poltergeist

Axion(-like fields) can explain the cosmological dark matter (DM) abundance and /or the baryon asymmetry of the Universe (BAU). In particular, the axion rotation dynamics, a la the Affleck-Dine mechanism, open up new mechanisms for production of DM and BAU. When the axion rotation energy density dominates the energy density of the universe, a transient matter-dominated (MD) era and a kination era can arise. In this talk, we point out that the quick change of the equation of state in the MD-to-kination transition produces gravitational waves at the nonlinear orders of cosmological perturbation theory (the so-called "Poltergeist mechanism"). The resultant stochastic gravitational-wave background can be observed by future gravitational-wave observatories even if the power of the axion perturbations, the source of the gravitational waves, has the size similar to that of the primordial curvature perturbations, namely, $\mathcal{O}(10^{-9})$.

Speaker: Takahiro Terada (Institute for Basic Science)

Axion_Poltergeist.pdf

17:30 Gravitational waves from quasi-stable cosmic strings

We discuss the stochastic gravitational wave background emitted from a network of 'quasi-stable' strings and its realization in grand unified theories. A symmetry breaking in the early universe produces monopoles that suffer partial inflation. A subsequent symmetry breaking at a lower energy scale creates cosmic strings which are effectively stable against the breaking via Schwinger monopole-pair creation. As the monopoles reenter the horizon, we will have monopole-antimonopoles connected by strings and further loop formation essentially ceases. As a consequence, the lower frequency part of the gravitational wave spectrum will be suppressed in comparison with that from topologically stable cosmic strings.

Speaker: Rinku Maji (Jeonbuk National University)

talk_PPC2023.pdf

17:50 Probing ultra-small scale cosmological structures with diffractive lensing of GW

Gravitational waves (GW) radiated by compact binary coalescences can be diffracted by astrophysical-size objects due to long wavelengths. This is so-called diffractive lensing. The length scale of the diffraction is determined by the geometric mean of GW wavelength and the effective distance to the lens, and it becomes O(1 pc) assuming GW frequency ~ 1Hz and the distance to lens ~ 1 Gpc. Therefore, diffractive lensing phenomena can be used to probe cosmological structures around parsec length scales assuming proper GW sources and detectors. With this idea, I'll explore the prospect of probing very light dark matter (sub-) halo. Furthermore, I will discuss how we can constrain the sub-parsec matter power spectrum even when we can not detect a single diffractive lensing event.

Speaker: Han Gil Choi (Center for Theoretical Physics of Universe, Institute for Basic Science)

Probing ultra-small scale cosmological structures with diffractive lensing of gravitational waves

Wednesday, 14 June

09:00 → 10:30 Plenary: Cosmology 2

Convener: Jai-chan Hwang

09:00 CMB Physics

Speaker: Donghui Jeong (Pennsylvania State University)

20230614_PPC2023.pdf

09:30 Dark Energy and H0 Tension

Speaker: Arman Shafieloo (Korea Astronomy and Space Science Institute (KASI))

10:00 Modified Gravity

Speaker: Prof. Masahide Yamaguchi (IBS-CTPU)

10:30 → 11:00 Coffee & Break

11:00 → 12:30 Plenary: Gravitational Wave

Convener: Chang Sub Shin (Institute for Basic Science)

11:00 Promise of persistent multi-messenger nano-hertz GW astronomy

Supermassive Black Holes (SMBHs) thrive at the centres of massive galaxies and galaxy mergers
can lead to SMBH binaries with orbital periods of years. Such systems emit nano-hertz
gravitational waves (GWs) which can be detected by employing networks of precisely
timed milli-second pulsars.
The rapidly maturing Pulsar Timing Arrays like NANOGrav, EPTA, InPTA, CPTA and PPTA, are expected
to detect and characterise such GWs in the very near future under
the auspices of the International Pulsar Timing Array (IPTA) consortium.
I will argue why this consortium has the potential to pursue
persistent multi-messenger nano-hertz GW astronomy during the Square Kilometre Array era
with a specific example.

Speaker: Prof. A. Gopakumar (Tata Institute of Fundamental Research, Mumbai)

Gopu_talk

11:30 Gravitational Wave Measurements

Speaker: Tjonnie Li (KU Leuven)

main2.pdf

12:00 Multi-Messenger Astronomy with 7-Dimensional Telescope

The 2017 detection of the binary neutron star (BNS) merger event in both gravitational wave (GW) and electromagnetic wave (EM), GW170817, has shown the great potential for multi-messenger astronomy, allowing us to understand the link between neutron star mergers and gamma-ray bursts, physical mechanisms and environments of the EM counterpart, kilonova (KN), and cosmology with GW sources. Yet, GW170817 is still the only GW event for which MMA was possible. With the start of the LVK O4 run in May 2023, the situation is now changing. The forecast is about 10 BNS merger event detections during O4, with many of them having a GW localization accuracy on par with GW170817. To capitalize on the anticipated GW source discoveries, we have prepared an optical EM follow-up network of telescopes named the Gravitational-wave EM Counterpart Korean Observatory (GECKO). In particular, we are now constructing a new facility, the 7-Dimensional Telescope (7DT) in Chile for multi-messenger astronomy. 7DT is a multiple-telescope system that can perform spectral mapping over a wide field of view (> 1 deg2) and will be efficient in catching KNe associated with future GW events. A partial system of 7DT started operation. In this talk, we will outline the current challenges of optical/NIR counterpart observations for the KNe discovery and outline our past GW optical follow-up activities. Then we will introduce 7DT and our observing strategy and early results using the telescope.

Speaker: Myungshin Im (Seoul National University)

12:30 → 12:40 Conference Photo

12:40 → 14:00 Lunch

14:00 → 15:00 Plenary: Machine Learning in High Energy Physics

Convener: Myeonghun Park (Seoul National University of Science and Technology)

14:00 Collider Phenomenology with Machine Learning

Speaker: Prof. Mihoko Nojiri (KEK)

PPC2023nojiri.pdf

14:30 Machine Learning in High Energy Physics

Speaker: David Shih (Rutgers University)

PPC 2023 Plenary Talk.pdf

15:00 → 15:30 Coffee & Break

15:30 → 18:00 Free discussion & Social

18:00 → 21:00 Banquet

Thursday, 15 June

09:00 → 10:30 Plenary: Collider 2

Convener: Mihoko Nojiri (KEK)

09:00 Future Colliders in Theoretical Perspectives

Speaker: Prof. Lian-Tao Wang (University of Chicago)

PPC2023-LiantaoWang.pdf

09:30 Searches for BSM and LLP signals at the LHC

Speaker: Prof. Louie Dartmoor Corpe (Laboratoire de Physique de Clermont)

LCORPE_PPC2023_June2023.pdf

10:00 BSM Higgs, W', and DM searches at the LHC

Speaker: JeongEun Lee (Seoul National University)

PPC2023_BSMHiggsWprimeDM_FINAL (1).pdf

10:30 → 11:00 Coffee & Break

11:00 → 12:00 Plenary: Flavor

Convener: Seong Chan Park (Yonsei University)

11:00 Status of flavor anomalies with Belle & Belle II

Recently there have been much interest with the so-called B-physics anomalies or tensions from B-factory experiments, including Belle, Belle II, BaBar, and LHCb experiments. Some of them are related with the lepton flavor universality, while there are other tensions e.g. in the CKM matrix element $V_{cb}$ and $V_{ub}$. Also, in the past, there was a tension in the direct CP asymmetry in $B \to K \pi$ decays. In this talk, we review the current experimental status of such anomalies and related subjects in $B$ decays from the existing measurements, and present the prospects on these in Belle II and LHCb.

Speaker: Youngjoon Kwon (Yonsei University)

PPC2023_y.j.Kwon_v.1.0.pdf

11:30 Muon g-2

Speaker: Prof. Kim Siang Khaw (TD Lee Institute)

12:00 → 14:00 Lunch

14:00 → 16:00 Parallel: Cosmology 3

Convener: Masahide Yamaguchi (IBS-CTPU)

14:00 Magnetic Reconnection in the Wakes of Cosmic Strings

The motion of cosmic strings in the universe leads to the generation of wakes behind them. We study magnetized wakes of cosmic strings moving in the post recombination plasma. We show that magnetic reconnection can occur in the post shock region. Since the width of the cosmic string wake is very small, the reconnection occurs over a very short length scale. The reconnection leads to a large amount of kinetic energy being released in the post shock region of the cosmic string wake. This enhances the kinetic energy released during the reconnection. We make a rudimentary estimate of the kinetic energy released by the magnetic reconnection in cosmic string wakes and show that it can account for low-energy Gamma Ray Bursts (GRBs) in the post recombination era.

Keywords: cosmic strings, shocks, magnetic reconnection.

DOI: https://doi.org/10.3847/1538-4357/acb4ef

Speaker: Dilip Kumar (School of Physics, University of Hyderabad, Telangana, India)

14:20 Scalar-Tensor Gravity at the First Loop

Possible implementations of perturbative quantum gravity for scalar tensor models are discussed. In particular, the perturbative approach generates new non-minimal couplings between a scalar field and gravity, and provides a way to calculate the one-loop scalar field effective potential. A brief overview of the perturbative approach is given. We show how the theory generates non-minimal kinetic couplings, beyond the Horndeski coupling, and effective potentials. The role of these results in the context of cosmology is discussed.

Speaker: Dr Boris Latosh (Center for Theoretical Physics of the Universe IBS)

Latosh_PPC_2023.pdf

14:40 Ultraviolet Unitarity Violations in Non-minimally Coupled Scalar-Starobinsky Inflation

We perform the calculation for tree-level ultraviolet unitarity violation scales for scalar-R^2 inflation models by including an additional R^2|Φ|^2-type term. Due to certain constraints, we resort to the Einstein frame for our calculations, where we separate our analysis between metric and Palatini formulations. We follow recent works in this line that debunk the naive predictions for unitarity violations in Higgs' inflation models to determine how to accurately estimate the behaviour of scattering amplitudes in the UV limit. Later, we work out different cases by assuming potentials corresponding to known inflation scenarios (like Higgs' inflation) so we could predict the range of coupling parameters for which the theories would remain unitary up to the Planckian regime. We also try to find the behaviour of the scattering amplitudes for these theories during the transition from inflationary to reheating epoch.

Speaker: Archit Vidyarthi (Indian Institute of Science Education and Research Bhopal)

archit_ppc.pdf

15:00 Effective field theory of the cuscuton

I will introduce the effective field theory (EFT) of the cuscuton. The cuscuton has the intriguing property that when present in a theory it does not propagate any scalar degrees of freedom, but only the two gravitational ones. Even more interestingly, it appears in several places in cosmology, such as in modified gravity, varying speed of light theories, and it has been shown to be the low-energy limit to Horava-Liftzing gravity. Using a geometric description we derive an EFT for the cuscuton. The resulting action is comprised from the Einstein-Hilbert term coupled to a scalar as well lovelock terms such as the dynamical Gauss-Bonnet action. We show this theory does not propagate a scalar degree of freedom. This framework can be extended to incorporate additional terms in the cuscuton EFT, leading to a richer phenomenology.

Speaker: Maria Mylova (Ewha Womans University, Seoul, South Korea)

MM_PPC23.pdf

15:20 Gauged Quintessence

We introduce the gauged quintessence model, in which the dark energy field (quintessence) has a $U(1)$ gauge symmetry. This is a kind of realization of interacting quintessence model and the first quintessence model under a gauge symmetry. We identify the radial part of the complex scalar as the dark energy field (quintessence), while the angular part is the longitudinal component of a new gauge boson. It brings interesting characters to dark energy physics. The $U(1)$ gauge boson can affect the quintessence dynamics, and the solicited dark energy properties can constrain the gauge coupling constant. While the uncoupled quintessence model severely suffers from the Hubble tension, the gauged quintessence might alleviate the situation.

Speaker: Jaeok Yi (KAIST)

Gauged Quintessence.pdf

15:40 Mass-varying gauge boson that couples to the dark energy field

We study the dark gauge boson in the gauged quintessence model. The gauged quintessence is the dark energy field under a gauge symmetry, and therefore its mass varies as the quintessence scalar value changes. The change of the dark gauge boson mass brings interesting consequences. The evolution of the universe is sensitively affected by the mass-varying dark gauge boson. We study various phenomenology of the dark gauge boson, including its production, evolution, and other implications.

Speaker: Jiheon Lee (KAIST)

Mass-varying gauge boson that couples to the dark energy field.pdf

14:00 → 16:00 Parallel: Dark Matter 5

Convener: Gaurav Tomar (Chungnam National University, South Korea)

14:00 Quantum theory of dark matter scattering

A long-range force between dark matter particles makes significant impacts on dark phenomenology.
It enhances the annihilation cross section at the late Universe (Sommerfeld enhancement), which affects the prospects for detecting annihilation products (indirect detection experiments).
It also leads to a large self-scattering cross section, which forms a significant core in dark matter halos.
These two effects exhibit an interesting correlation: for example, when the Sommerfeld enhancement factor is significantly large for a certain value of the parameter (resonance), the self-scattering cross section is also resonantly enhanced.
In this talk, we first review how the Sommerfeld enhancement factor and self-scattering cross section are computed by using a scattering state in quantum mechanics.
Then, we formulate the relation between these two effects and discuss how the correlated resonance is understood in our formulation.

Speaker: Ayuki Kamada (Institute of Theoretical Physics, University of Warsaw)

kamada0615.pdf

14:20 Multi-dimensional optimization methods to analyze the null results of WIMP direct detection experiments with conservative bounds.

To analyze WIMP of spin one half with a standard Maxwellian velocity distribution we calculate the maximal variation of the exclusion plot from the null results of 9 direct detection experiments. And the exclusion plot for each Wilson coefficient of the most general Galilean invariant WIMP nucleon effective Hamiltonian generalizes to a band delimited by the most constraining bound which corresponds to the maximal cancellation among the contribution of Wilson coefficients and that of all the other couplings of the effective theory. From 14 operators, multi-dimensionality is needed for Wilson coefficients that are 56 combination of contact and long range interaction with WIMP-proton and WIMP-neutron scattering. The variation of exclusion plot can reach 3 orders of magnitude and reduces to a factor as small as a few for the Wilson coefficients of the effective interactions where the WIMP couples to the nuclear spin. It is effective to combinate the experiments using proton-odd and neutron-odd targets. An extremely high level of cancellation producing a question for the reliability of the result is required for some of the conservation bounds. By showing that is affects some of couplings driven by operators O1, O3, O11, O12 and O15, in particular the case of interference between contact and long range interaction, this issue is analyzed in a systematic way.

Speaker: Injun Jeong (Sogang University)

ppc2023injunjeong.pdf

14:40 Halo-independent bounds of WIMP-nucleon couplings from direct detection and neutrino observations in non-relativistic effective theory

I will discuss the halo-independent bounds on the WIMP-nucleon couplings of the non-relativistic effective Hamiltonian that drives the scattering process off nuclei of a WIMP of spin 1/2. For most of the couplings the degree of relaxation of the halo-independent bounds compared to those obtained with the Standard Halo Model is relatively moderate in the low and high WIMP mass regimes while in the intermediate mass range it can be large. An exception with moderate bounds at all WIMP masses is observed in the case of several WIMP-proton couplings that depend on the nuclear spin and on the WIMP incoming velocity.

Speaker: Sunghyun Kang (Sogang University)

2023_ppc.pdf

15:00 Anapole Moment of Neutralino Dark Matter

Albeit typically considered to be "dark", a dark matter particle can interact electromagnetically with ordinary matter via higher multipole moments generated at the quantum level. If dark matter particles are of Dirac nature, only a millicharge, an electric- and magnetic dipole and an anapole moment can exist. If however it is a Majorana fermion---as naturally predicted by some BSM theories such as the MSSM---the only allowed electromagnetic moment is the anapole moment. In this talk I will present a model-independent UV-finite calculation of the anapole moment of a generic Majorana fermion including contributions from both scalar-fermion and vector-fermion pairs at the one-loop level. Based on these general results I will present the predictions for the anapole moment of the lightest neutralino within the MSSM serving as an archetepyical DM candidate. Finally I compare these theory predictions with experimental limits on the anapole moment of dark matter utilizing nuclear recoil experiments such as XENON1T.

Speaker: Merlin Reichard (TUM)

PPC23_Reichard.pdf

15:20 Updated Constraints and Future Prospects on Majoron Dark Matter

Majorons are (pseudo-)Nambu-Goldstone bosons associated with lepton number symmetry breaking due to the Majorana mass term of neutrinos introduced in the seesaw mechanism. They are good dark matter candidates since their lifetime is suppressed by the lepton number breaking scale. We update constraints and discuss future prospects on majoron dark matter in the singlet majoron models based on neutrino, gamma-ray, and cosmic-ray telescopes in the mass region of MeV-10 TeV.

Speaker: Michiru Niibo (Ochanomizu University)

ppc_niibo03.pdf

15:40 Positivity Bounds on Higgs-Portal Dark Matter

We consider the positivity bounds for WIMP scalar dark matter with effective Higgs-portal couplings up to dimension-8 operators. Taking the superposed states for Standard Model Higgs and scalar dark matter, we show the part of the parameter space for the effective couplings, otherwise unconstrained by phenomenological bounds, is ruled out by the positivity bounds on the dimension-8 derivative operators. We find that Dark matter relic density, direct and indirect detection, and LHC constraints are complementary to the positivity bounds in constraining the effective Higgs-portal couplings. In the effective theory obtained from massive graviton or radion, there appears a correlation between dimension-8 operators and other effective Higgs-portal couplings for which the strong constraint from direct detection can be evaded. Nailing down the parameter space mainly by relic density, direct detection, and positivity bounds, we find that there are observable cosmic ray signals coming from the Dark matter annihilations into a pair of Higgs bosons, WW or ZZ.

Speaker: Seongsik KIm (Chung-Ang University)

2023 June PPC2023_SSK_v3.pdf

14:00 → 16:00 Parallel: Neutrino 3

Convener: Pouya Bakhti (JBNU)

14:00 Search for interactions of neutrinos with Dark Matter from distant point sources with the IceCube Neutrino Telescope

The discovery of neutrino signals from distant sources, recently reported with TXS 0506+056 and NGC 1068 respectively, provide opportunities for searching for BSM interactions that neutrinos might experience on their paths. One potential scenario of interest is the interaction between neutrinos and dark matter, which is expected to be abundantly spread over the Universe. If high-energy neutrinos from extragalactic sources interact with dark matter during their propagation, their fluxes may be suppressed at specific energy ranges after the interactions. These attenuation signatures from the interaction might be measurable on Earth with large neutrino telescopes such as the IceCube Neutrino Observatory. The present analysis is focused on searching for BSM interactions of high-energy neutrinos from the IceCube-identified astrophysical neutrino sources with sub-GeV mass dark matter and several benchmark mediator cases using the upgoing track-like events. In this talk, sensitivity studies about the interaction of neutrinos and dark matter with IceCube are presented.

Speaker: Woosik Kang (Sungkyunkwan University)

Woosik-IceCube_nuDM_DistSource-PPC2023.pdf

14:20 Investigating Lorentz Invariance Violation with the long baseline experiments P2O and DUNE

One of the basic foundations of quantum field theory is Lorentz invariance. The spontaneous breaking of Lorentz symmetry at a high energy scale can be studied at low energy extensions like the Standard model in a model-independent way through effective field theory (EFT). The present and future Long-baseline neutrino experiments can give a scope to observe such a Planck-suppressed physics of Lorentz invariance violation
(LIV). In this talk, I will discuss how two future long baseline proposals DUNE and P2O can explore the LIV physics efficiently. We illustrate how the individual LIV parameters affect neutrino oscillations at P2O and DUNE baselines at the level of probability and derive analytical expressions to understand interesting degeneracies and other features. we estimate constraints on the individual LIV parameters at 95% confidence level (C.L.) intervals stemming from the combined analysis of simulated P2O and DUNE datasets, and highlight the improvement over the existing constraints.

Speaker: Mehedi Masud (IBS-CTPU)

slides_masud_ppc.pdf

14:40 Probing sterile neutrino dark matter in the PTOLEMY-like experiment

We study the prospect to detect the cosmic background of sterile neutrinos in the tritium $\beta$-decay, such as the PTOLEMY-like experiments. The sterile neutrino with mass between 1 eV - 10 keV may contribute to the local density as warm or cold DM component. In this study, we investigate the possibility for searching them in the models with different production in the early Universe, without assuming sterile neutrino as full dark matter component. In these models, especially with low-reheating temperature and late-time phase transition, the capture rate per year can be greatly enhanced to be $\mathcal O(10)$ around the mass range $10\:-\:100\ \text{eV}$ without violating other astrophysical and cosmological observations.

Speaker: Seong Moon Yoo (Sung Kyun Kwan University)

2023_PPC_SMYoo.pdf

16:00 → 16:30 Coffee & Break

16:30 → 18:30 Parallel: BSM Theories and Flavor Physics

Convener: Sang Hui Im (Center for Theoretical Physics of the Universe, Institute for Basic Science, Korea)

16:30 Festina-Lente Bound on Higgs vacuum structure, inflation, and dark photon

The recently suggested Festina-Lente (FL) bound provides a lower bound on the masses of U(1) charged particles in terms of the positive vacuum energy. Since the charged particle masses in the Standard Model (SM) are generated by the Higgs mechanism, the FL bound provides a testbed of consistent Higgs potentials in the current dark energy-dominated universe as well as during inflation. We study the implications of the FL bound on the UV behavior of the Higgs potential for a miniscule vacuum energy, as in the current universe. We also present values of the Hubble parameter and the Higgs vacuum expectation value allowed by the FL bound during inflation, which implies that the Higgs cannot stay at the electroweak scale during this epoch. We also discuss dark photon physics.

Speaker: Seong Chan Park (Yonsei University)

20230615_PPC2023_SCP.pdf

16:50 Geometric view for the PNGB potential

We investigate the pseudo-Nambu-Goldstone bosons (pNGBs) potential in the geometrical point of view.
In this talk I will discuss how to essentially organise or structurally understand the pNGB potential without recourse to the UV symmetries.

Speaker: Dong Woo Kang (KIAS)

17:10 On the mass spectrum of heavy Higgs bosons in two-Higgs-doublet model in the light of the CDF $W$-mass anomaly

We analyze the mass spectrum of the charged and neutral Higgs bosons in the framework of two Higgs doublet model (2HDM) in the light of the precision measurement of the $W$ boson mass by the CDF collaboration. We have considered the most general 2HDM potential with explicit CP violation in the Higgs basis which contains the three CP-mixed neutral mass eigenstates $H_1$, $H_2$, and $H_3$ with $M_{H_1}\leq M_{H_2}\leq M_{H_3}$. The high-precision CDF measurement of the $W$ boson mass is characterized by the large positive value of the $T$ parameter. By identifying the lightest neutral Higgs boson $H_1$ as the SM-like one discovered at the LHC, we find that it is necessary to have the mass splitting between the charged Higgs boson $H^\pm$ and the second heaviest neutral one $H_2$ to accommodate the sizable positive deviation of the $T$ parameter from its SM value of $0$. By combining the mass splitting between $H^\pm$ and $H_2$ with the theoretical constraints from the perturbative unitarity and for the Higgs potential to be bounded from below, we implement comprehensive analysis of the mass spectrum of the heavy Higgs bosons taking account of the effects of deviation from the alignment limit and also the mass splitting between $H_3$ and $H_2$. We further analyze the behavior of the heavy-Higgs mass spectrum according to the variation of the $T$ parameter. Finally, we discuss some benchmarking scenarios for the searches of heavy Higgs bosons at future colliders such as the high luminosity option of the LHC and a 100 TeV hadron collider.

Speaker: Yongtae Heo (Chonnam National University)

2HDM Heo PPC 2023(2).pdf

17:30 Dark Z boson and the W boson mass anomaly

The dark Z boson is a new vector particle induced by an additional Abelian gauge symmetry. It interacts with the SM fermions via kinetic and mass mixings and provides a new source of parity violation. It is known that such a parity-violating effect can be tested by future precious measurements of the weak mixing angle at low energies. In this talk, we discuss the effect of the dark Z boson on the W boson mass measurement. Mixings between dark Z and the electroweak gauge bosons induce deviations in the SM gauge couplings, and it gives a possibility of explaining the W boson mass anomaly reported by the CDF collaboration. We will show that the dark Z model can explain the W boson mass anomaly with satisfying other experimental constraints within 2σ, while simple dark photon models cannot. We also discuss how to verify such a dark Z boson in future experiments.

Speaker: Kazuki Enomoto (KAIST)

KE_PPC2023.pdf

17:50 Quark and lepton hierarchies from S4' modular flavor symmetry

We proposed models in which the hierarchical structure of the quark and lepton masses and mixing are explained by the $S_4^\prime$ modular flavor symmetry. This is the first explicit example which realizes all of the mass and mixing hierarchies from a single modular symmetry. The hierarchies are predominantly explained by the Froggatt-Nielsen mechanism due to the residual $Z_4^T$ symmetry, where the modulus is stabilized near the fixed point $\sim i\infty$. The numerical factors from canonical normalizations and modular forms also give important effects to explain the observed patterns with $\mathcal{O}(1)$ parameters.

Speaker: Junichiro Kawamura (IBS-CTPU)

slide_PPC2023_JKawamura.pdf

18:10 Nonminimally Assisted Inflation: A General Analysis

The effects of a scalar field, known as the “assistant field,” which nonminimally couples to gravity, on single-field inflationary models are studied. The analysis provides analytical expressions for inflationary observables such as the spectral index (𝑛𝑠), the tensor-to-scalar ratio (𝑟), and the local-type nonlinearity parameter (𝑓𝑁𝐿(𝑙𝑜𝑐𝑎𝑙)). The presence of the assistant field leads to a lowering of 𝑛𝑠 and 𝑟 in most of the parameter space, compared to the original predictions. In some cases, ns may increase due to the assistant field. This revives compatibility between ruled-out single-field models and the latest observations by Planck-BICEP/Keck. The results are demonstrated using three example models: loop inflation, power-law inflation, and hybrid inflation.

Speaker: Sang Chul Hyun (Yonsei University)

PPC_Sang_Chul_Hyun.pdf

16:30 → 18:10 Parallel: Dark Matter 6

Convener: Ayuki Kamada (Institute of Theoretical Physics, University of Warsaw)

16:30 Mapping Dark Matter in the Milky Way using Normalizing Flows and Gaia DR3

We present a novel, data-driven analysis of Galactic dynamics, using unsupervised machine learning -- in the form of density estimation with normalizing flows -- to learn the underlying phase space distribution of 6 million nearby stars from the Gaia DR3 catalog. Solving the collisionless Boltzmann equation with the assumption of approximate equilibrium, we calculate -- for the first time ever -- a model-free, unbinned, fully 3D map of the local acceleration and mass density fields within a 3 kpc sphere around the Sun. As our approach makes no assumptions about symmetries, we can test for signs of disequilibrium in our results. We find our results are consistent with equilibrium at the 10% level, limited by the current precision of the normalizing flows. After subtracting the known contribution of stars and gas from the calculated mass density, we find clear evidence for dark matter throughout the analyzed volume. Assuming spherical symmetry and averaging mass density measurements, we find a local dark matter density of 0.47±0.05GeV/cm3. We fit our results to a generalized NFW, and find a profile broadly consistent with other recent analyses.

Speaker: Sung Hak Lim (Rutgers University)

PPC2023-pub.pdf

16:50 Observational phenomena on black hole with dark matter dress

The accretion of dark matter around the black hole could lead to the formation of surrounding halo. Such a dark matter dressed black hole can leave characteristic imprints in the observations including gamma-ray, gravitational lensing and gravitational waves. In this talk, I will talk several observational phenomena on the black hole with dark matter dress.

Speaker: Xing-Yu Yang (KIAS)

pre.pdf

17:10 Non-adiabatic evolution of a dark sector in the presence of $U(1)_{L_\mu-L_\tau}$ gauge symmetry

In a secluded dark sector scenario, the connection between the visible and the dark sector can be established through a portal coupling and its presence opens up the possibility of non-adiabatic evolution of the dark sector. Here, we have considered a $U(1)_{L_\mu - L_\tau} \otimes U(1)_X$ extension of the standard model (SM) to study the evolution of a decoupled dark sector in a radiation-dominated Universe. Depending on the values of the portal coupling ($\epsilon$), dark sector gauge coupling ($g_X$), the mass of the dark matter ($m_\chi$), and the mass of the dark vector boson ($m_{Z^\prime}$), we study the temperature evolution of the dark sector as well as the various non-equilibrium stages of the dark sector in detail. Furthermore, we have also investigated the constraints on the model parameters from various laboratory and astrophysical searches. We have found that for $m_{Z^\prime}< 100 \rm MeV$, parameter space for the non-adiabatic evolution of the dark sector is significantly constrained from the observations of beam dump experiments, stellar cooling etc. The bounds from direct detection, and self-interaction of dark matter (SIDM) for the mass ratio $r\equiv m_{\chi}/m_{Z^\prime} = 10^{-3}$ are consistent with the relic density satisfied region and these bounds will be more relaxed for larger values of $r$. However the constraints from the measurement of diffuse $\gamma$-ray background flux and cosmic microwave background (CMB) anisotropy are strongest for $r = 10^{-1}$ and for smaller values of r, they are not significant.

Speaker: Sougata Ganguly (Chungnam National University)

PPC2023-SGanguly.pdf

17:30 Light cold dark matter from non-thermal decay

Our investigation focuses on determining the mass range and free-streaming length scale of dark matter resulting from heavy objects' non-thermal decay. These objects may be dominant or sub-dominant at the time of decay. Our findings indicate that the resulting dark matter can be exceptionally light, possibly below the keV scale, and still comply with the Lyman-α constraints on free-streaming length. The possible scenario is the axion dark matter from subdominant saxion decay and dark matter from subdominant Q-ball. We present two specific instances of this type of light cold dark matter.

Speaker: Junghoon Joh (Theoretical Astro-particle physics and Cosmology lab, SungKyunKwan University)

PPC_JJ.pdf

16:30 → 18:50 Parallel: Gravitational Wave 2

Convener: Han Gil Choi (Center for Theoretical Physics of Universe, Institute for Basic Science)

16:30 Indian Pulsar Timing Array: Observational and theoretical efforts

Speaker: Gopakuma Archamveedu

Gopu_InPTA

16:50 Detection of gravitational waves by electromagnetic cavity: a review

Gravitational wave (GW) detection using electromagnetic (EM) cavities has garnered significant attention in recent years. With ongoing experiments on axion detection using highly sensitive electromagnetic cavity, there is potential to apply these existing facilities to GW detection, opening up a new channel of GW observation. In this review, we comprehensively examine the principles of GW detection using EM cavities within the framework of general relativity. We expect that it not only provides analysis of existing EM cavity experiments and but also offers insights for the design of new ones.

Speaker: Dr Chan Park (IBS CTPU)

[2023.06.15] Detection of gravitational waves by electromagnetic cavity.pdf

17:10 Optimizing the geometry of axion haloscopes for gravitational wave searches

In the presence of electromagnetic fields, gravitational waves (GWs) induce oscillating magnetic fields proportional to the GW amplitude.

That the same is true for an axion implies that a synergy exists between the experimental effort to probe axion dark-matter and the search for high frequency GWs.

We derive selection rules which determine the parametric sensitivity of different detector geometries to axions and GWs for cylindrically symmetric magnetic (or electric) external field configurations.

In particular, we demonstrate that optimizing for the axion signal always eliminates the leading order contribution of the GW signal, and show how small modifications to the pick-up loop can remedy this.

Speaker: Sung Mook Lee (Yonsei University)

Sung Mook.pdf

17:30 Exploring the ultralight axion dark matter by the gravitational wave and radio telescopes

We study the new observational effects of ultralight axion-like particles by the space-borne gravitational wave detector and the radio telescopes. Taking the neutron star-black hole binary as an example, we demonstrate that the phase of gravitational waveform could be obviously modified by the slow depletion of the axion cloud around the black hole formed through the superradiance process. Other effects from dynamical friction with axion dark matter and dipole radiation are also discussed. Finally, we study the detectability of the ultralight axion particles at LISA and TianQin.

Speaker: Prof. Fa Peng Huang (Sun Yat-sen University)

ultralightaxionshort.pdf

17:50 Sensitivity to Dark Sector Scales from Gravitational Wave Signatures

We consider gravitational sound wave signals produced by a first-order phase transition in a theory with a generic renormalizable thermal effective potential of power law form. We find the frequency and amplitude of the gravitational wave signal can be related in a straightforward manner to the parameters of the thermal effective potential. This leads to a general conclusion; if the mass of the dark Higgs is less than 1% of the dark Higgs vacuum expectation value, then the gravitational wave signal will be unobservable at all upcoming and planned gravitational wave observatories. Although the understanding of gravitational wave production at cosmological phase transitions is still evolving, we expect this result to be robust.

Speaker: Sumit Ghosh (Korea Institute for Advanced Study)

PPC_2023_SG.pdf

18:10 Observing ultralow-frequency gravitational waves with pulsar parameter drift

Gravitational waves with frequencies below 1 nHz are notoriously difficult to detect, and experimental methodologies for their detection are lacking. In this talk, I will present a new means of probing this regime by using secular drifts in observed pulsar timing parameters. I will begin by presenting two complementary observables for which the systematic shift induced by ultralow-frequency gravitational waves can be extracted. I will then show the results of searches for both continuous and stochastic signals in this regime using existing data for these observables, and demonstrate that the astrophysically-motivated background from supermassive black hole mergers should be imminently observable with this new technique.

Speaker: William DeRocco (University of California, Santa Cruz)

PPC_Daejeon_2023.pdf

18:30 Macroscopic Dark Matter Detection with Extreme Mass Ratio Inspirals and mini-EMRIs

I will discuss the detection of macroscopic dark matter candidates such as primordial black holes, boson stars, etc, with a special kind of binary system, the extreme mass ratio inspirals, which is a main target for future space-based gravitational wave detectors, and emphasize its advantages in detection of subsolar exotic compact objects. I will also introduce the mini-EMRIs that can be searched for at LIGO.

Speaker: Huaike Guo (University of Chinese Academy of Sciences)

Huaike.pdf

Friday, 16 June

09:00 → 10:30 Plenary: Dark Matter 2

Convener: Raymond Co (University of Minnesota)

09:00 Experimental efforts in pursuit of direct detection of cosmic dark matter

Dark matter is a cornerstone of modern cosmology, and its identification is widely expected to reveal physics beyond the Standard Model. A wealth of well-motivated theories predicts new particles that could account for the dark matter content of the universe, and which may be detected by Earthly detectors. In this talk, I will review the most common methods used to search for possible kinetic energy transfer from cosmic dark matter to atoms in particle detectors, and the sensitivities demonstrated by these ‘direct detection’ experiments. I will also discuss the challenges and limitations facing these experiments, and R&D that may lead to more sensitive searches in future efforts. (Prepared by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-846609.)

Speaker: Jingke Xu (Lawrence Livermore National Laboratory)

PPC2023_DMDD_Xu.pdf

09:30 Light Dark Matter Searches

Speaker: Jia Liu (Peking University)

PPC-2023-JiaLiu-v2.pdf

10:00 Neutrinos in astrophysical explosions

Neutrinos play key roles in some of the most energetic astrophysical explosions such as core-collapse supernovae, binary neutron star mergers, and collapsars. Moreover, they are also unique messengers to probe the physical conditions deep inside these events opaque to electromagnetic emissions. In this talk, I will discuss recent developments in understanding the collective flavor oscillations of neutrinos in supernovae and in binary mergers as well as their possible implications. I will also talk about a potentially interesting signature due to the annihilation of high- and low-energy neutrinos on the produced spectra of high-energy neutrinos spectra from collapsars that may be relevant to the diffuse high-energy neutrino flux detected by the IceCube.

Speaker: Meng-Ru Wu (Institute of Physics, Academia Sinica)

230616_PPC2023_MRW.pdf

10:30 → 11:00 Coffee & Break

11:00 → 12:10 Plenary: Neutrino 2

Convener: Chang Hyon Ha (Institute for Basic Science & Chung-Ang University)

11:00 Neutrino Telescopes

Speaker: Aya Ishihara (ICEHAP, Chiba University)

PPC2023_NeutinoTelescopes_v1.pdf

11:30 Yemilab physics overview

Yemilab is a newly constructed underground laboratory located in Korea, featuring over 1,000 meters of rock overburden and a dedicated area of 3,000 m2 for rare event search experiments. Completed in the fall of 2022 within the site of an operating iron mining company, Yemilab is now open for new experiments. The installations of the AMoRE neutrinoless double beta decay experiment and the COSINE dark matter search experiment are currently underway, with experiments scheduled to start as early as fall 2023. Yemilab also offers additional spaces for future experiments, including the largest cavern for a 2 kt liquid scintillator experiment, which are waiting for good physics proposals and proper funding. This presentation will focus on the physics programs currently underway at Yemilab, as well as future experiments that are being planned and prepared for.

Speaker: Dr Hyunsu Lee (IBS)

Yemilab.pdf

12:10 → 12:20 Introduction to PPC 2024

12:10 PPC 2024

Speaker: Prof. Giri Anjan (IIT, Hyderabad)

12:20 → 14:00 Lunch

14:00 → 15:30 Coffee & Discussion