藉由重力透鏡研究暗物質之結構

Studying Dark Matter Structure via Gravitational Lensing

詹弘旭(James Hung-Hsu Chan)

指導教授 ： 闕志鴻 ； 蘇游瑄

國立臺灣大學/理學院/物理學研究所/博士(2017年)

https://doi.org/10.6342/NTU201704218

摘要

揭曉暗物質 (dark matter, DM) 的本質在現代宇宙學中是非常重要的 課題。分折暗物質的結構更是對於星系生成及演化和大尺度結構非常 的關鍵。為了完成這個目標，我們同時使用宇宙數值模擬和天文觀測 資料。特別的是，我們使用重力透鏡效應 (grivatational lensing) 去探索 宇宙的黑暗成份。我們發表一套新的工具，CHITAH，去偵測影像巡 天觀測中的重力透鏡系統。CHITAH 已經在超廣角可見光相機巡天計 畫中 (the HSC survey) 尋找到數個有公信力的系統，並有計劃進行後續 觀測。在模擬部份，我們發表了一段有效演化波暗物質 (ψDM) 和星粒 子的工具。我們發現星系中的孤粒子核 (soliton) 會因為星粒子的重力 而吸收約二倍的質量，並滿足比例關係。在未來，使用類星體重力透 鏡系統和宇宙模擬能使我們證實/推翻波暗物質的模型。

關鍵字

暗物質 ； 重力透鏡

並列摘要

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.

並列關鍵字

dark matter ； gravitational lensing

參考文獻

[2] T. Anguita, C. Faure, J.-P. Kneib, J. Wambsganss, C. Knobel, A. M. Koekemoer, and M. Limousin. COSMOS 5921+0638: characterization and analysis of a new strong gravitationally lensed AGN. A&A, 507:35–46, Nov. 2009.

[3] M. W. Auger, T. Treu, A. S. Bolton, R. Gavazzi, L. V. E. Koopmans, P. J. Mar- shall, L. A. Moustakas, and S. Burles. The Sloan Lens ACS Survey. X. Stellar, Dynamical, and Total Mass Correlations of Massive Early-type Galaxies. ApJ, 724:511–525, Nov. 2010.

[6] I. K. Baldry, M. Alpaslan, A. E. Bauer, J. Bland-Hawthorn, S. Brough, M. E. Clu- ver, S. M. Croom, L. J. M. Davies, S. P. Driver, M. L. P. Gunawardhana, B. W. Holwerda, A. M. Hopkins, L. S. Kelvin, J. Liske, Á. R. López-Sánchez, J. Loveday, P. Norberg, J. Peacock, A. S. G. Robotham, and E. N. Taylor. Galaxy And Mass Assembly (GAMA): AUTOZ spectral redshift measurements, confidence and errors. MNRAS, 441:2440–2451, July 2014.

[8] M. Barnabè, O. Czoske, L. V. E. Koopmans, T. Treu, and A. S. Bolton. Two- dimensional kinematics of SLACS lenses - III. Mass structure and dynamics of early-type lens galaxies beyond z ∼ 0.1. MNRAS, 415:2215–2232, Aug. 2011.

[9] G. Bertone and D. Merritt. Dark Matter Dynamics and Indirect Detection. Modern Physics Letters A, 20:1021–1036, 2005.