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

Session

Parallel: Cosmology 2

13 Jun 2023, 14:00

Conference room (2nd floor) (IBS Science and Culture Center)

Conveners

Parallel: Cosmology 2

• Seokhoon Yun (University of Padova)

58. Gravitational waves and UHECRs in a supersymmetric local U(1) B-L model

Wan-Il Park (Jeonbuk National University)

13/06/2023, 14:00

Cosmology

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.

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

Alexandros Papageorgiou (IBS-CTPU)

13/06/2023, 14:20

Cosmology

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...

153. Small Scale Structure of Multi-component Dark Matter

Jeong Han Kim (Chungbuk National University)

13/06/2023, 14:40

Cosmology

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.

38. Joint reconstructions of growth and expansion histories with minimal assumptions

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

13/06/2023, 15:00

Cosmology

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...

104. Revisiting the gravitational lensing analysis of the Bullet Cluster using radio waves

Youngsub Yoon

13/06/2023, 15:20

Cosmology

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...

25. Nonminimally Assisted Inflation: A General Analysis

Sang Chul Hyun (Yonsei HEP-COSMO)

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 ($n_s$), the tensor-to-scalar ratio ($r$), and the local-type nonlinearity parameter ($f _{(local)}^{NL}$). The presence of the assistant field...

83. WIMPy Leptogenesis in Non-Standard Cosmologies

Devabrat Mahanta (Abhayapuri College)

Cosmology

We study the possibility of generating baryon asymmetry of the universe from dark matter (DM) annihilations during non-standard cosmological epochs. Considering the DM to be of weakly interacting massive particle (WIMP) type, the generation of baryon asymmetry via leptogenesis route is studied where WIMP DM annihilation produces a non-zero lepton asymmetry. Adopting a minimal particle physics...