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The mass of our Milky Way

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Science China(Physics,Mechanics & Astronomy) 2020年第10期63卷 1-46页

作者： WenTing Wang JiaXin Han Marius Cautun ZhaoZhou li Miho N.Ishigaki Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China ka.li ipmu(WPI) UTIASThe University of TokyoKashiwaChiba 277-8583Japan Leiden Observatory Leiden UniversityPO Box 9513NL-2300 RA Leidenthe Netherlands Astronomical Institute Tohoku UniversityAoba-kuSendaiMiyagi 980-8578Japan

We perform an extensive review of the numerous studies and methods used to determine the total mass of the Milky *** group the various studies into seven broad classes according to their modeling *** classes include:i)estimating Galactic escape velocity using high velocity objects;ii)measuring the rotation curve through terminal and circular velocities;iii)modeling halo stars,globular clusters and satellite galaxies with the spherical Jeans equation and iv)with phase-space distribution functions;v)simulating and modeling the dynamics of stellar streams and their progenitors;vi)modeling the motion of the Milky Way,M31 and other distant satellites under the framework of Local Group timing argument;and vii)measurements made by linking the brightest Galactic satellites to their counterparts in *** each class of methods,we introduce their theoretical and observational background,the method itself,the sample of available tracer objects,model assumptions,uncertainties,limits and the corresponding measurements that have been achieved in the *** the measured total masses within the radial range probed by tracer objects and the extrapolated virial masses are discussed and *** also discuss the role of modern numerical simulations in terms of helping to validate model assumptions,understanding systematic uncertainties and calibrating the *** measurements in the last two decades show a factor of two scatters,recent measurements using Gaia DR2 data are approaching a higher *** end with a detailed discussion of future developments in the field,especially as the size and quality of the observational data will increase tremendously with current and future *** such cases,the systematic uncertainties will be dominant and thus will necessitate a much more rigorous testing and characterization of the various mass determination methods.

关键词： Milky Way dark matter stellar halo dynamics satellite galaxies

Neutrino Mass Constraints from Reconstructing the Large-scale Structure:Systematic Uncertainty

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Research in Astronomy and Astrophysics 2023年第6期23卷 65-73页

作者： Chok Lap Chung Derek Inman Xin Wang Erhao Shang Zi Zhuang Fucheng Yuan Ue-li Pen School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 5109082China ka.li ipmu(WPI) UTIASThe University of TokyoKashiwaChiba 277-8583Japan CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area SYSUChina Institute of Astronomy and Astrophysics Academia Sinica645 N Aohoku PlHiloHI 96720USA Canadian Institute for Theoretical Astrophysics 60 St.George StreetTorontoON M5S 3H8Canada Canadian Institute for Advanced Research 180 Dundas St WestTorontoON M5G 1Z8Canada Dunlap Institute for Astronomy and Astrophysics University of Toronto50 St George StreetTorontoON M5S 3H4Canada Perimeter Institute of Theoretical Physics 31 Caroline Street NorthWaterlooON N2L 2Y5Canada

We examine the possibility of applying the baryonic acoustic oscillation reconstruction method to improve the neutrino massΣm_ν*** to the Gaussianization of the process,we demonstrate that the reconstruction algorithm could improve the measurement accuracy by roughly a factor of *** the other hand,the reconstruction process itself becomes a source of systematic *** the algorithm is supposed to produce the displacement field from a density distribution,various approximations cause the reconstructed output to deviate on intermediate ***,it is still possible to benefit from this Gaussianized field,given that we can carefully calibrate the“transfer function”between the reconstruction output and theoretical displacement divergence from *** limitation of this approach is then set by the numerical stability of this transfer *** an ensemble of simulations,we show that such systematic error could become comparable to statistical uncertainties for a DESI-like survey and be safely neglected for other less ambitious surveys.

关键词： (cosmology:)large-scale structure of universe cosmology:observations neutrinos

Precision Higgs physics at the CEPC

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Chinese Physics C 2019年第4期43卷 5-44页

作者： Fenfen An Yu Bai Chunhui Chen Xin Chen Zhenxing Chen Joao Guimaraes da Costa Zhenwei Cui Yaquan Fang Chengdong Fu Jun Gao Yanyan Gao Yuanning Gao Shaofeng Ge Jiayin Gu Fangyi Guo Jun Guo Tao Han Shuang Han Hongjian He Xianke He Xiaogang He Jifeng Hu Shih-Chieh Hsu Shan Jin Maoqiang Jing Susmita Jyotishmati Ryuta Kiuchi Chia-Ming Kuo Peizhu Lai Boyang li Congqiao li Gang li Haifeng li liang li Shu li Tong li Qiang li Hao liang Zhijun liang libo liao Bo liu Jianbei liu Tao liu Zhen liu Xinchou Lou lianliang Ma Bruce Mellado Xin Mo Mila Pandurovic Jianming Qian Zhuoni Qian Nikolaos Rompotis Manqi Ruan Alex Schuy lianyou Shan Jingyuan Shi Xin Shi Shufang Su Dayong Wang Jin Wang liantao Wang Yifang Wang Yuqian Wei Yue Xu Haijun Yang Ying Yang Weiming Yao Dan Yu ka.li Zhang Zhaoru Zhang Mingrui Zhao Xianghu Zhao Ning Zhou Institute of High Energy Physics Department of Physics and Astronomy Iowa State University Department of Physics Southeast University Department of Engineering Physics Physics Department Tsinghua University School of Physics Peking University University of Chinese Academy of Science (UCAS) Physical Science Laboratory Huairou National Comprehensive Science Center School of Physics and Astronomy Shanghai Jiao Tong University KLPPAC-MoE SKLPPC Department of Physics University of Liverpool ka.li ipmu (WPI) UTIAS The University of Tokyo Department of Physics University of California PRISMA Cluster of Excellence & Mainz Institute of Theoretical Physics Johannes Gutenberg-Universit?t Mainz Department of Modern Physics University of Science and Technology of China Department of Physics & Astronomy University of Pittsburgh Tsung-Dao Lee Institute Department of Physics National Taiwan University Department of Physics University of Washington Department of Physics Nanjing University School of Nuclear Science and Technology University of South China Department of Physics University of Texas at Dallas Department of Physics and Center for High Energy and High Field Physics National Central University Institute of Frontier and Interdisciplinary Science and Key Laboratory of Particle Physics and Particle Irradiation (MOE) Shandong University Department of Physics Hong Kong University of Science and Technology Theoretical Physics Department Fermi National Accelerator Laboratory Maryland Center for Fundamental Physics Department of Physics University of Maryland School of Physics and Institute for Collider Particle Physics University of the Witwatersrand iThemba LABS National Research Foundation Vinca Institute of Nuclear Sciences University of Belgrade Department of Physics University of Michigan Center for Theoretical Physics of the Universe Institute of Basic Science Department of Physics University of Arizona Department of Physics University of Chicago Lawrence Berkeley National Laboratory Chi

The discovery of the Higgs boson with its mass around 125 GeV by the ATLAS and CMS Collaborations marked the beginning of a new era in high energy *** Higgs boson will be the subject of extensive studies of the ongoing LHC *** the same time,lepton collider based Higgs factories have been proposed as a possible next step beyond the LHC,with its main goal to precisely measure the properties of the Higgs boson and probe potential new physics associated with the Higgs *** Circular Electron Positron Collider(CEPC)is one of such proposed Higgs *** CEPC is an e^+e^- circular collider proposed by and to be hosted in *** in a tunnel of approximately 100 km in circumference,it will operate at a center-of-mass energy of 240 GeV as the Higgs *** this paper,we present the first estimates on the precision of the Higgs boson property measurements achievable at the CEPC and discuss implications of these measurements.

关键词： CEPC Higgs bos on Higgs boson properties Higgs boson couplings Higgs factory effective field theory,EFT

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暗晕子结构的数值搜寻与统计性质

天文学进展 2018年第3期36卷 306-324页

作者：李昭洲韩家信中国科学院上海天文台星系与宇宙学重点实验室上海200030 中国科学院大学北京100049 ka.li ipmu(WPI) UTIASThe University of Tokyo

宇宙学数值模拟预言的暗晕及其子结构的统计性质,被广泛应用于星系形成模型、近邻宇宙学、红移巡天、宇宙大尺度结构、引力透镜和暗物质搜寻等研究领域。在精确宇宙学时代,随着天文观测能力的不断增长,人们对模型精度提出了更高的要求,... 详细信息

宇宙学数值模拟预言的暗晕及其子结构的统计性质,被广泛应用于星系形成模型、近邻宇宙学、红移巡天、宇宙大尺度结构、引力透镜和暗物质搜寻等研究领域。在精确宇宙学时代,随着天文观测能力的不断增长,人们对模型精度提出了更高的要求,因此,数值模拟及其分析工具将继续起到不可替代的巨大作用。数值模拟中物质结构的性质往往与具体的搜寻算法有关,从最初通过数值模拟发现子晕到现在的20年里,结构搜寻算法有了极大的发展,新算法不断涌现。了解不同数值搜寻算法的实现及其差异,有助于分析模拟结果的系统差和不确定性,增强研究的可重复性。通过总结现代子晕数值搜寻的基本方法,并以几种典型的搜寻算法为例,探讨了它们之间的异同,及其对相关研究的影响;回顾了子晕的基本统计性质,包括质量函数、空间分布和密度轮廓等,以及这些统计结果对搜寻算法的依赖。此外,还讨论了重子物理的影响。

关键词：数值模拟结构形成暗物质晕暗物质晕子结构半解析模型统计