Studying Dark Matter Structure via Gravitational Lensing

• Main Authors: James Hung-Hsu Chan, 詹弘旭
• Other Authors: Tzihong Chiueh
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/xdcfk7

博士 === 國立臺灣大學 === 物理學研究所 === 106 === Unveiling the nature of dark matter has become the golden question in modern cosmology, and understanding the structure/sub-structure of dark mat- ter in the Universe is important for our understanding of the formation/evolution of galaxies and large-scale structures. To achieve this goal, we conduct both cosmological simulations and astrophysical observations. In particular, we exploit a direct technique, gravitational lensing, to explore the dark side of the Universe. We present a novel algorithm, CHITAH, to classify lens systems in imaging surveys. CHITAH has classified a few promising lens candidates in the Hyper-Surprime Cam (HSC) survey, including lensed quasars and lensed galaxies with follow-up observations planned. In the simulation regime, we present an efficient algorithm for wave-like dark matter (ψDM) model plus stars. We discover that a solitonic core can absorb mass by a factor of 2 from its host halo to satisfy the scaling relation even in the presence of additional star gravity. Using lensed quasars and comparing with simulation results will allow us confirm/disconfirm ψDM model.