2026 CTPU-CGA−Yonsei Joint School and Workshop

25 Feb 2026, 09:00 → 27 Feb 2026, 13:20 Asia/Seoul

B438 (IBS HQ)

Banquet venue: 편백연가 6:00PM

The purpose of this joint school and workshop is to share recent developments in cosmology, gravity, and astroparticle physics with members of IBS CTPU-CGA and the Yonsei HEP-COSMO Lab, and to foster active academic exchange and collaboration between the two groups.

Organizing Committee:
 
Yongsoo Jho (Yonsei U)
Dong-Won Jung (IBS CTPU-CGA)
Seong Chan Park (Yonsei U)
Masahide Yamaguchi (IBS CTPU-CGA)

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Wednesday, 25 February

16:00 → 18:00 opening and Ice breaking: Ice breaking with 3 minute self introductions

18:00 → 20:00 Reception

Thursday, 26 February

10:00 → 11:30 1hr+30min

10:00 Simulating and Probing the First 0.1 Billion Years of the Universe (50min+10min)

The 21-cm line of hydrogen is emerging as a promising probe of the first 0.1 billion years of cosmic history. We conduct a suite of hydrodynamical simulations to precisely model the impact of sub-Mpc structure formation on 21-cm emission during these early epochs. We find that nonlinear matter clumping leads to ~10% changes in the sky-averaged 21-cm intensity and order-unity (~100%) changes in the 21-cm power spectrum in the standard cold dark matter scenario, relative to previous theoretical predictions that neglected nonlinear effects. These nonlinear clumping effects will be detectable by upcoming surveys and can also vary to a detectable level in non-standard dark matter models, opening a new avenue for constraining dark matter properties. Our results provide a theoretical framework for interpreting future 21-cm observational data.

Speaker: Dr Hyunbae Park (IBS CTPU-CGA)

11:00 Cosmic Neutrino Background Detection with Tritium (25min+5min)

Speaker: Dr Michiru Uwabo-Niibo (IBS CTPU-CGA)

11:30 → 13:30 lunch

13:30 → 14:30 30min+30min

13:30 Ultraheavy dark matter and Ultra-high-energy neutrino signals with horizontal symmetry

Speaker: Dr Yongsoo Jho (Yonsei U)

14:00 Dark star mergers as a source of signals for gravitational wave

Speaker: Dr Boris Betancourt Kamenetskaia (IBS CTPU-CGA)

14:30 → 15:00 break

15:00 → 16:30 1hr+30min

15:00 Dark Matter: if not WIMP, then what?

Speaker: Prof. Seong Chan Park (Yonsei U)

16:00 Beyond the Starobinsky model after ACT

Speaker: Mr Min Gi Park (Yonsei U)

16:30 → 17:00 break

17:00 → 18:00 30min+30min

17:00 Probing High-Energy Physics with the SGWB from Cosmic Strings

Speaker: Dr Ivan Rybak (IBS CTPU-CGA)

17:30 cancelled

18:00 → 20:00 banquet

Friday, 27 February

10:00 → 11:30 30min+30min+30min

10:00 Aspects of Sommerfeld Enhancement in the light of Halo gamma-ray excess

Speaker: Mr Jeonghwan Park (Yonsei U)

10:30 High Frequency Gravitational Wave Detection with Superconducting Transmon Qubit

Speaker: Mr Heechan Yi (Yonsei U)

11:00 Nonsingular Cosmologies in Horndeski Gravity

Speaker: Dr Pavel Petrov (IBS CTPU-CGA)

11:30 → 11:50 closing