中文
相关论文

相关论文: Blind source separation of the stellar halo

200 篇论文

We analyse the density profiles of the stellar halo populations in eight Milky-Way mass galaxies, simulated within the $\Lambda$-Cold Dark Matter scenario. We find that accreted stars can be well-fitted by an Einasto profile, as well as any…

星系天体物理 · 物理学 2015-06-22 Patricia B. Tissera , Cecilia Scannapieco

We review Galactic halo formation theories and supporting evidence, in particular kinematics and detailed chemical abundances of stars in some relevant globular clusters as well as Local Group dwarf galaxies. Outer halo red HB clusters tend…

天体物理学 · 物理学 2009-11-13 Doug Geisler , George Wallerstein , Verne V. Smith , Dana I. Casetti-Dinescu

The difference in density profiles of the contributions from different density peaks to dark matter halos results in certain expectations about the Milky Way's stellar halo. We cut our simulated halo stars into two populations: those…

天体物理学 · 物理学 2009-03-19 C. B. Brook , D. Kawata , H. Martel , B. K. Gibson , E. Scannapieco

We analyze an adaptive mesh refinement hydrodynamic cosmological simulation of a Milky Way-sized galaxy to study the cold gas in the halo. HI observations of the Milky Way and other nearby spirals have revealed the presence of such gas in…

星系天体物理 · 物理学 2015-06-04 Ximena Fernández , M. Ryan Joung , Mary E. Putman

Since the chemical abundances of stars are the fossil records of the physical conditions in galaxies, they provide the key information for recovering the assembly history of galaxies. In this work, we explore the chemo-chrono-kinematics of…

We use a 200 $h^{-1}Mpc$ a side N-body simulation to study the mass accretion history (MAH) of dark matter halos to be accreted by larger halos, which we call infall halos. We define a quantity $a_{\rm nf}\equiv (1+z_{\rm f})/(1+z_{\rm…

宇宙学与河外天体物理 · 物理学 2018-05-18 Jingjing Shi , Huiyuan Wang , H. J. Mo , Lizhi Xie , Xiaoyu Wang , Andrea Lapi , Ravi K. Sheth

We use a series of high-resolution simulations of a `Milky-Way' halo coupled to semi-analytic methods to study the formation of our own Galaxy and of its stellar halo. The physical properties of our model Milky Way, as well as the age and…

天体物理学 · 物理学 2009-11-13 Gabriella De Lucia , Amina Helmi

We develop a hybrid model of galactic chemical evolution that combines a multi-ring computation of chemical enrichment with a prescription for stellar migration and the vertical distribution of stellar populations informed by a cosmological…

The Milky Way's million degree gaseous halo contains a considerable amount of mass that, depending on its structural properties, can be a significant mass component. In order to analyze the structure of the Galactic halo, we use XMM-Newton…

星系天体物理 · 物理学 2015-06-15 Matthew Miller , Joel Bregman

The abundance ratio N/O is a useful tool to study the interplay of galactic processes, e.g. star formation efficiency, time-scale of infall and outflow loading factor We aim to trace log(N/O) versus [Fe/H] in the Milky Way and to compare it…

This paper presents theoretical star formation and chemical enrichment histories for the stellar halo of the Milky Way based on new chemodynamical modeling. The goal of this study is to assess the extent to which metal-poor stars in the…

星系天体物理 · 物理学 2014-11-20 Jason Tumlinson

We estimate the Milky Way (MW) halo properties using satellite kinematic data including the latest measurements from Gaia DR2. With a simulation-based 6D phase-space distribution function (DF) of satellite kinematics, we can infer halo…

星系天体物理 · 物理学 2020-05-06 Zhao-Zhou Li , Yong-Zhong Qian , Jiaxin Han , Ting S. Li , Wenting Wang , Y. P. Jing

Ongoing star formation in the Milky Way requires continuous gaseous fuel from accretion. Previous work has suggested that the accretion of dwarf galaxies could provide the needed gas for this process. In this work we investigate whether…

星系天体物理 · 物理学 2011-02-11 J. E. G. Peek

$\Lambda$CDM cosmology predicts the hierarchical formation of galaxies which build up mass by merger events and accreting smaller systems. The stellar halo of the Milky Way has proven to be useful a tool for tracing this accretion history.…

Recent progress of nucleosynthesis work as well as the discovery of a kilonova associated with the gravitational-wave source GW170817 indicates that neutron star mergers (NSM) can be a site of the r-process. Several studies of galactic…

星系天体物理 · 物理学 2021-07-14 Shinya Wanajo , Yutaka Hirai , Nikos Prantzos

I discuss three different topics concerning the chemical evolution of the Milky Way (MW). 1) The metallicity distribution of the MW halo; it is shown that this distribution can be analytically derived in the framework of the hierarchical…

天体物理学 · 物理学 2015-05-13 N. Prantzos

The Galactic stellar halo is predicted to have formed at least partially from the tidal disruption of accreted dwarf galaxies. This assembly history should be detectable in the orbital and chemical properties of stars. The H3 Survey is…

We analyze the anisotropy profile of the Milky Way's smooth, diffuse stellar halo using SDSS/SEGUE blue horizontal branch stars and SDSS/SEGUE and LAMOST K giants. These intrinsically luminous stars allow us to probe the halo to…

星系天体物理 · 物理学 2021-10-04 Sarah A. Bird , Xiang-Xiang Xue , Chao Liu , Juntai Shen , Chris Flynn , Chengqun Yang , Gang Zhao , Hai-Jun Tian

To account for the observed differential metallicity distribution (DMD) of the Milky Way halo, a semi-analytical model is presented in the framework of the hierarchical merging paradigm for structure formation. It is assumed that the Milky…

天体物理学 · 物理学 2009-11-13 Nikos Prantzos

It is well established that the chemical structure of the Milky Way exhibits a bimodality with respect to the $\alpha$-enhancement of stars at a given [Fe/H]. This has been studied largely based on a bulk $\alpha$ abundance, computed as a…

星系天体物理 · 物理学 2019-09-20 Kirsten Blancato , Melissa Ness , Kathryn V. Johnston , Jan Rybizki , Megan Bedell