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相关论文: Velocity Dispersion Profile of the Milky Way Halo

200 篇论文

We have compiled a new sample of 240 halo objects with accurate distance and radial velocity measurements, including globular clusters, satellite galaxies, field blue horizontal branch stars and red giant stars from the Spaghetti survey.…

We measure the three components of velocity dispersion, $\sigma_{R},\sigma_{\theta},\sigma_{\phi}$, for stars within 6 < R < 30 kpc of the Milky Way using a new radial velocity sample from the MMT telescope. We combine our measurements with…

星系天体物理 · 物理学 2015-11-11 Charles King , Warren R. Brown , Margaret J. Geller , Scott J. Kenyon

Modeling the Milky Way stellar halo requires well-determined density and velocity anisotropy profiles. However, it has been challenging to gather a large sample of stars with six-dimensional data that extend beyond 40 kpc to map the outer…

We re-analyse the velocity-dispersion profile sigma(r) at radii r>10 kpc in the Galactic stellar halo, recently derived by Battaglia et al. (2005), who concluded that, for constant velocity anisotropy of the tracers, these data rule out a…

天体物理学 · 物理学 2009-11-11 Walter Dehnen , Dean McLaughlin , Jalpesh Sachania

Fast radio bursts offer the opportunity to place new constraints on the mass and density profile of hot and ionized gas in galactic haloes. We test here the X-ray emission and dispersion measure predicted by different gas profiles for the…

星系天体物理 · 物理学 2020-06-03 Laura C. Keating , Ue-Li Pen

We derive new constraints on the mass of the Milky Way's dark matter halo, based on a set of halo stars from SDSS as kinematic tracers. Our sample comprises 2401 rigorously selected Blue Horizontal-Branch (BHB) halo stars drawn from SDSS…

The Milky Way halo is one of the few galactic haloes that provides a unique insight into galaxy formation by resolved stellar populations. Here, we present a catalogue of $\sim$47 million halo stars selected independent of parallax and…

The {\it Gaia} mission has provided the largest catalogue ever of sources with tangential velocity information. However, using this catalogue for dynamical studies is difficult because most of the stars lack line-of-sight velocity…

星系天体物理 · 物理学 2021-06-02 Helmer H. Koppelman , Amina Helmi

We increase the number of remote halo tracers by using blue horizontal branch (BHB) stars out to Galactocentric distances of 130 kpc. We use SDSS EDR photometry and the VLT to detect 16 BHB stars at Galactocentric distances 70 < r < 130,…

天体物理学 · 物理学 2007-05-23 L. Clewley , S. J. Warren , P. C. Hewett , M. Wilkinson , W. N. Evans

A simple model for the Milky Way halo is presented. It has a flat rotation curve in the inner regions, but the density falls off sharply beyond an outer edge. This truncated, flat rotation curve (TF) model possesses a rich family of simple…

天体物理学 · 物理学 2008-11-26 M. I. Wilkinson , N. W. Evans

The goal of this survey is to study the formation and evolution of the Milky Way halo to deduce its assembly history and the 3D distribution of mass in the Milky Way. The combination of multi-band photometry, Gaia proper motion and parallax…

Most of known RR Lyraes are type ab RR Lyraes (RRLab), and they are the excellent tool to map the Milky Way and its substructures. We find that 1148 RRLab stars determined by Drake et al.(2013) have been observed by spectroscopic surveys of…

星系天体物理 · 物理学 2018-03-28 Iminhaji Ablimit , Gang Zhao

We use the IllustrisTNG (TNG) cosmological, hydrodynamical simulations of galaxy formation to measure the velocity dispersion profiles of dark matter and star particles in Milky Way-mass, galaxy group, and cluster-scale dark matter halos.…

星系天体物理 · 物理学 2021-05-19 Sownak Bose , Abraham Loeb

Recently, we determined a lower bound for the Milky Way mass in a point mass approximation. This result was obtained for most general spherically symmetric phase-space distribution functions consistent with a measured radial velocity…

星系天体物理 · 物理学 2016-11-04 Szymon Sikora , Łukasz Bratek , Joanna Jałocha , Marek Kutschera

The escape velocity profile of the Milky Way offers a crucial and independent measurement of its underlying mass distribution and dark matter properties. Using a sample of stars from Gaia DR3 with 6D kinematics and strict quality cuts, we…

星系天体物理 · 物理学 2024-02-02 Cian Roche , Lina Necib , Tongyan Lin , Xiaowei Ou , Tri Nguyen

We present the velocity dispersion of red giant branch (RGB) stars in M31's halo, derived by modeling the line of sight velocity distribution of over 5000 stars in 50 fields spread throughout M31's stellar halo. The dataset was obtained as…

We build a sample of distant (D > 80 kpc) stellar halo stars with measured radial velocities. Faint ($20 < g <22$) candidate blue horizontal branch (BHB) stars were selected using the deep, but wide, multi-epoch Sloan Digital Sky Survey…

Halo stars orbit within the potential of the Milky Way and hence their kinematics can be used to understand the underlying mass distribution. However, the inferred mass distribution depends sensitively upon assumptions made on the density…

星系天体物理 · 物理学 2015-06-22 Prajwal R. Kafle , Sanjib Sharma , Geraint F. Lewis , Joss Bland-Hawthorn

The Hypervelocity Star survey presents the currently largest sample of radial velocity measurements of halo stars out to 80 kpc. We apply spherical Jeans modeling to these data in order to derive the mass profile of the Galaxy. We restrict…

星系天体物理 · 物理学 2010-08-31 Oleg Y. Gnedin , Warren R. Brown , Margaret J. Geller , Scott J. Kenyon

The halo of our Galaxy is populated with a significant number of high-velocity clouds (HVCs) moving with a speed up to $500$ km/s. It is suggested that these HVCs might contain a non-negligible fraction of the missing baryons. The main aim…

星系天体物理 · 物理学 2024-12-03 Noraiz Tahir , Martin Lopez Corredoira , Francesco De Paolis
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