세종대학교 두드림 비교과통합관리시스템

물리천문학과 콜로퀴움

‧강연 제목 :  Robust constraints on the self-interacting cross-section of dark matter using LHCs (Large Halo Colliders)

‧연사 : 연세대학교 지명국 교수님

‧일시 : 2024년 11월 13일 (수요일) 17:00~18:30

‧진행 방법 : 영실관 601호

‧신청 가능 대상 : 세종대학교 재학생 누구나

‧신청기간 :  11월  5일 ~ 11월 13일

‧강의 초록

In particle physics experiments, no solid laboratory detection of dark matter has been achieved, while evidence for dark matter remains pervasive in observational astronomy. In astrophysics, dark matter serves as a fundamental assumption enabling the observed structure formation of the universe. Previously, offsets between galaxies and mass in colliding clusters were considered promising indicators for assessing the self-interaction cross-section of dark matter. However, prior investigations using these offsets were hindered by substantial biases related to the phase and geometry of mergers. I will introduce a reliable constraint on dark matter self-interaction using an innovative and effective approach, analyzing observations of cluster collisions with double radio relics. By utilizing the distance between radio relics relative to the distance between halos as a gauge for dark matter properties, we have established an upper limit of 0.30 cm² g⁻¹ for the self-interaction cross-section at a 68% confidence level. This represents the first robust result derived from colliding clusters, accounting for uncertainties in factors such as mass distribution, viewing angle, collision velocity, merger phase, impact parameter, and gas profile slope.