CTPU-CKC Joint Focus Program: Let there be light (particles) Workshop

Dec 2, 2024, 9:30 AM → Dec 6, 2024, 5:00 PM Asia/Seoul

CTPU Seminar Room (IBS Building 4th Floor)

Let there be light (particles) Workshop

2nd December - 6th December   2024

IBS-CTPU-PTC, Daejeon, Korea
 

The "CTPU-CKC Joint Focus Program: Let there be light (particles) Workshop" will be held from Dec 2nd (Mon) to Dec 6th (Fri), 2024, at the Institute for Basic Science (IBS) in Daejeon, Korea.

This workshop will focus on the physics of light dark sector, encompassing topics such as dark matter, dark force, and related subjects in physics beyond the standard model of particle physics.

Our goal is to bring together leading theorists, experimentalists, and observers in cosmology, astrophysics, and particle physics to discuss the latest results, ideas, and future prospects on physics of dark sector.

Presentations are by invitation only.

 

This workshop is sponsored by CERN-Korea Committee (CKC) and IBS-CTPU-PTC.

 

Invited Speakers

Haipeng An (Tsinghua U.) Itay Bloch (UC, Berkeley and LBNL, Berkeley) Salvatore Bottaro (Tel Aviv U.) Dhong Yeon Cheong (Yonsei U.) Sebastian Ellis (Geneva U.) Sougata Ganguly (IBS-CTPU) Claudio Gatti (INFN Frascati) Junu Jeong (Stockholm U.) Seung Joon Lee (KIAS) Seong-Sik Kim (CAU) Joshua T. Ruderman (New York U.) Chen Sun (Los Alamos & ICTP-Trieste) Marco Taoso (INFN Turin) Luca Teodori (Weizmann Inst.)

Organizers

• Andrea Caputo (CERN)
• Hyung Do Kim (SNU & CKC)
• Tae Hyun Jung (IBS-CTPU)
• Seokhoon Yun  (IBS-CTPU)

 

Monday, December 2

Registration

Opening remark

1 [Joshua T. Ruderman] ROMP Dark Matter

IBS_DM_online.pdf

Lunch

2 [Seong-Sik Kim] Self-Resonant Dark Matter

We consider a new mechanism for enhancing the self-scattering and annihilation crosssections for dark matter with multiple components but without a light mediator. The lighter dark matter component plays a role of the u-channel pole in the elastic co-scattering for dark matter, leading to a large self-scattering cross section and a Sommerfeld enhancement for semi-annihilation processes. Taking the effective theory approach for self-resonant dark matter, we present various combinations of multiple dark matter components with spins and parities that show a u-channel pole in the co-scattering processes. Adopting dark photon and dark Higgs portals for self-resonant dark matter, we impose the relic density condition and indirect detection bounds on semi-annihilation channels with Sommerfeld enhancement and discuss potential signals for direct detection experiments.

2024 Dec CTPU-CKC_SSK_v1.pdf

2:45 PM Coffee break

3 [Marco Taoso] Searching for the axion from dwarf spheroidal galaxies and the Sun

Axions and axion-like particles (ALPs) are some of the best-motivated candidates for dark matter. Their coupling to photons leads to radiative decays of axion dark matter and axion-photon conversion in an external magnetic field. We discuss two methods to search for these signals by exploiting astrophysical data. The first is based on spectroscopic optical observations of a sample of five classical and ultra-faint dwarf spheroidal galaxies. We present new limits on ALPs radiative decays for ALPs masses in the eV range. The second strategy relies on the conversion of axions into photons in the Sun’s magnetic field. Leveraging the production of axions in the solar core, we report strong bounds for axion masses below 1e-4 eV from solar X-ray observations.

MTaoso_IBS.pdf

Tuesday, December 3

4 [Haipeng An] Searching for dark photon dark matter using radio technology

I am going to first give a brief review on recent development of dark photon dark matter production mechanisms. Then I am going to focus on dark photon dark matter in the radio frequency region, and talk about how to use large scale radio telescope to search for it.

IBS_2024_HaipengAN.pdf

Lunch

5 [Junu Jeong] Search for High-Mass Dark Matter Axions

The axion, initially proposed to resolve the strong CP problem, has gained prominence as a compelling candidate for dark matter, particularly in its ultralight form. Recent theoretical studies, supported by simulations of cosmic evolution, indicate that dark matter axions may exist in a relatively higher mass range than previously explored. This development has catalyzed innovative proposals and experimental efforts to explore this promising parameter space. In this talk, I will provide an overview of the global experimental efforts in the search for high-mass dark matter axions, emphasizing key concepts and challenges.

JunuJeong_HighMassAxion.pptx

2:45 PM Coffee break

6 [Claudio Gatti] Search for Axion Dark Matter at INFN

The axion, a pseudoscalar particle originally introduced to solve the ‘’strong CP problem’’, is a well motivated dark-matter candidate with a mass lying in a broad range from peV to few meV. Axions clustered inside our galaxy may be observed by means of detectors called “haloscopes” consisting in a resonant cavity immersed in a static magnetic field that triggers the axion conversion to microwave photons. I will present the status and perspectives for axion dark-matter searches at INFN. I’ll show the recent results of QUAX, an INFN experiment that operates two haloscopes at the national laboratories in Frascati and Legnaro, and discuss how to improve them using quantum sensing. Finally, I will present FLASH a large haloscope to be built by recycling a superconducting solenoid of 1.4 m radius, 2.2 m length and 1.1 T field at LNF. FLASH will probe axions with a mass around 1 micro-eV, as well as dark photons and high frequency gravitational waves. Recently, after the refurbishing of the cryogenic lines and of the control system, the magnet was energized with about 2700 ampere to generate, again after two decades, a 1.1 T field.

CTPU-CKC-CGatti.pdf

Banquet: [Workshop dinner] Tofu & Pork

Wednesday, December 4

7 [Sebastian Ellis] Dark Matter Signals from the Ionosphere

Ionosphere_IBS.pdf

Lunch

8 [Dhong Yeon Cheong] A Quantum Description of Wave Dark Matter

In this talk, I will outline a fundamentally quantum description of bosonic dark matter. Following a quantum optics inspired approach, I will show the density operator of dark matter, which takes a mixed Gaussian form over a coherent state basis. This formalism also allows a precise description of quantities related to dark matter coherence. I will further give a continuous description of dark matter through the wave-particle transition, where the density fluctuation in various scales evolves between the two limits, showing a unique behavior near the boundary of these descriptions.

Speaker: Dhong Yeon Cheong (Yonsei University)

IBS_Quantum_Wave_DM_D.Y.Cheong.pdf

2:45 PM Coffee break

9 [Sougata Ganguly] Constraining Majoron from Big-Bang Nucleosynthesis

We estimate the Big Bang nucleosynthesis (BBN) constraint on the majoron in the mass range between 1MeV to 10GeV which dominantly decays into the standard model neutrinos. When the majoron lifetime is shorter than 1sec, the injected neutrinos mainly heat up background plasma, which alters the relation between photon temperature and background neutrino temperature. For a lifetime longer than 1sec, most of the injected neutrinos directly contribute to the protons-to-neutrons conversion. In both cases, deuterium and helium abundances are enhanced, while the constraint from the deuterium is stronger than that from the helium. ${}^7 {\rm Li}$ abundance gets decreased as a consequence of additional neutrons, but the parameter range that fits the observed ${}^7 {\rm Li}$ abundance is excluded by the deuterium constraint. We also estimate other cosmological constraints and compare them with the BBN bound.

BBN_Majoron_SGanguly_CKC_workshop_2024.pdf

Thursday, December 5

10 [Salvatore Bottaro] Hunting for New physics in Large Scale Structure of the Universe

Precision cosmology offers the possibility of testing the dynamics of the dark sector even if it is completely secluded from the visible one. As a first example, we consider the imprint of a long-range force mediated by a scalar field and acting solely between Dark Matter particles on the distribution of galaxies, also known as the large-scale structure (LSS) of the Universe. We derive the strongest constraint on such forces from a combination of Planck and BOSS data. In doing so, we consistently develop, for the first time, the Effective Field Theory of LSS in the presence of new dynamics in the dark sector. More general self-interactions of the scalar mediator can induce a dark first-order phase transition. We explore its effects on the CMB and LSS and discuss its interplay with the long-range force dynamics.

Bottaro.pdf

Lunch

11 [Luca Teodori] ULDM dynamical heating on Fornax-like system stars

The ULDM wave-like behavior is known to cause dynamical heating of stars. We investigate this effect on typical dwarf galaxy systems, with emphasis on Fornax, via numerical simulations. We show that kinematics data are in tension with an ULDM mass of m < 1e-21 eV. Extension to lower velocity dispersion systems may push the constrain to higher masses.

daejeong_talk.pdf

2:45 PM Coffee break

12 [Seung J. Lee] Axion dark matter from inflation-driven quantum phase transition

Banquet

Friday, December 6

13 [Itay Bloch] The RoW comag as a tool for DM detection

When bosonic Dark Matter (DM) has an ultra-light mass, it acts as a classical, coherent field. In many cases, and specifically for many models of axion-like-particles, this field has a magnetic-like effect on spins, and can therefore be measured by spin-based quantum magnetometers. I will explain the workings of quantum magnetometers, focusing on comagnetometers, which simultaneously utilize several species of atoms to achieve a variety of benefits. Currently, many such spin-based systems are limited by technical noises, such as their magnetic background. I will begin with a discussion of self compensating magnetometer, and from that move to my proposal for a new sensor called the RoW comag. The RoW comag should allow the removal of magnetic backgrounds at a tunable frequency, and would hence drastically enhance the reach of spin-based searches, allowing sensitivity to highly motivated DM models.

10:45 AM Coffee break

14 [Chen Sun] New “Twists” for Axion Searches

In this talk, I will first briefly review a few axion constraints derived from the astrophysical and late cosmology measurements, including the galaxy kinematics data from rotation curve, the radio signals from axion stimulated decay, the cosmic distance measurements from supernovae and galaxy clusters, and the solar axion detection enhanced by the recently proposed Axion Magnetic Resonance.// I will then focus on the mechanism of Axion Magnetic Resonance and its application to axion lab searches as well as its potential for astrophysical searches.

Closing