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Related papers: Velocity Dispersion Profile of the Milky Way Halo

200 papers

Rapid advance has been made recently in accurate distance measurements for nearby ($D < 11$ Mpc) galaxies based on the magnitude of the tip of red giant branch stars resolved with the Hubble Space Telescope. We use observational properties…

Astrophysics of Galaxies · Physics 2021-09-02 Igor D. Karachentsev , Olga G. Kashibadze

We use a particle tagging technique to dynamically populate the N-body Via Lactea II high-resolution simulation with stars. The method is calibrated using the observed luminosity function of Milky Way satellites and the concentration of…

Astrophysics of Galaxies · Physics 2015-05-28 Valery Rashkov , Piero Madau , Michael Kuhlen , Jurg Diemand

A new model of the Milky Way (MW) halo component of the dispersion measure (DM) for extragalactic sources, such as fast radio bursts (FRBs), is presented in light of recent diffuse X-ray observations. In addition to the spherical component…

High Energy Astrophysical Phenomena · Physics 2020-01-29 Shotaro Yamasaki , Tomonori Totani

We present robust constraints from the Sloan Digital Sky Survey (SDSS) on the shape and distribution of the dark matter halo within the Milky Way (MW). Using the number density distribution and kinematics of SDSS halo stars, we probe the…

We present a homogeneous spectroscopic dataset of 22,339 stars in 78 Milky Way dwarf galaxy satellites and globular clusters. All data were taken with the Keck II telescope and Deep Extragalactic Imaging Multiobject Spectrograph (DEIMOS)…

We have compiled a sample of 699 stars from the recent literature with detailed chemical abundance information (spanning -4.2 < [Fe/H] < +0.3), and we compute their space velocities and Galactic orbital parameters. We identify members of…

Astrophysics · Physics 2009-11-13 Ian U. Roederer

We present a comprehensive study of the velocity dispersion of the atomic (HI) and molecular (H2) gas components in the disks (R < R25) of a sample of 12 nearby spiral galaxies with moderate inclinations. Our analysis is based on sensitive…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-13 Anahi Caldu-Primo , Andreas Schruba , Fabian Walter , Adam Leroy , Karin Sandstrom , W. J. G. de Blok , Roger Ianjamasimanana , K. M. Mogotsi

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…

Astrophysics of Galaxies · Physics 2020-05-06 Zhao-Zhou Li , Yong-Zhong Qian , Jiaxin Han , Ting S. Li , Wenting Wang , Y. P. Jing

[Abridged] Motivated by upcoming data from astrometric and spectroscopic surveys of the Galaxy, we explore the chemical abundance properties and phase-space distributions in hierarchically-formed stellar halo simulations set in a LambdaCDM…

Astrophysics · Physics 2008-11-26 Andreea S. Font , Kathryn V. Johnston , James S. Bullock , Brant E. Robertson

Based on the first Gaia data release and spectroscopy from the LAMOST Data Release 4, we study the kinematics and chemistry of the local halo stars. The halo stars are identified kinematically with a relative speed of at least 220 km…

Astrophysics of Galaxies · Physics 2018-08-22 Cuihua Du , Hefan Li , Shuai Liu , Thomas Donlon , Heidi Jo Newberg

Hypervelocity stars (HVSs) travel from the Galactic Centre across the dark matter halo of the Milky Way, where they are observed with velocities in excess of the Galactic escape speed. Because of their quasi-radial trajectories, they…

Astrophysics of Galaxies · Physics 2019-06-14 O. Contigiani , E. M. Rossi , T. Marchetti

We use 3.6 $\mu$m photometry for 1154 disk galaxies ($i<65^{\circ}$) in the Spitzer Survey of Stellar Structure in Galaxies (S$^{4}$G, Sheth et al. 2010) to obtain the stellar component of the circular velocity. By combining the disk+bulge…

Astrophysics of Galaxies · Physics 2016-11-08 Simón Díaz-García , Heikki Salo , Eija Laurikainen , Ryan Leaman

We present a simple model that accurately describes various statistical properties of peculiar velocities of dark matter halos. We pay particular attention to the following two effects; first, the evolution of the halo peculiar velocity…

Astrophysics · Physics 2009-11-07 Takashi Hamana , Issha Kayo , Naoki Yoshida , Yasushi Suto , Y. P. Jing

Various laboratory-based experiments are underway attempting to detect dark matter directly. The event rates and detailed signals expected in these experiments depend on the dark matter phase space distribution on sub-milliparsec scales.…

Astrophysics · Physics 2011-08-31 Daniele S. M. Fantin , Michael R. Merrifield , Anne M. Green

We have determined masses, stellar mass functions and structural parameters of 112 Milky Way globular clusters by fitting a large set of N-body simulations to their velocity dispersion and surface density profiles. The velocity dispersion…

Astrophysics of Galaxies · Physics 2018-07-03 H. Baumgardt , M. Hilker

Theoretical and observational arguments suggest that there is a large amount of hot ($\sim 10^6$ K), diffuse gas residing in the Milky Way's halo, while its total mass and spatial distribution are still unclear. In this work, we present a…

Astrophysics of Galaxies · Physics 2020-05-06 Xiang-Er Fang , Fulai Guo , Ye-Fei Yuan

We present stellar velocity dispersion profiles for seven Milky Way dwarf spheroidal (dSph) satellite galaxies. We have measured 8394 line-of-sight velocities (+/- 2.5 km/s) for 6804 stars from high-resolution spectra obtained at the…

Gaia HyperVelocity Star (HVS) kinematic observations favor a local escape velocity of ~700 km/s, nearly forty-percent greater than conventional estimates. Combining HVS and dwarf galaxy satellite data reveal the global escape velocity…

Astrophysics of Galaxies · Physics 2022-10-18 Jeffrey M. La Fortune

Recent advances from astronomical surveys have revealed spatial, chemical, and kinematical inhomogeneities in the inner region of the stellar halo of the Milky Way Galaxy. In particular, large spectroscopic surveys, combined with Gaia…

Astrophysics of Galaxies · Physics 2020-07-08 Deokkeun An , Timothy C. Beers

Hypervelocity stars (HVS) traverse the Galaxy from the central black hole to the outer halo. We show that the Galactic potential within 200 pc acts as a high pass filter preventing low velocity HVS from reaching the halo. To trace the…

Astrophysics · Physics 2009-11-13 S. J. Kenyon , B. C. Bromley , M. J. Geller , W. R. Brown