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相关论文: Mapping the Remote Milky Way Halo using BHB stars …

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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…

We report on the global structure of the Milky Way (MW) stellar halo up to its outer boundary based on the analysis of blue-horizontal branch stars (BHBs). These halo tracers are extracted from the $(g,r,i,z)$ band multi-photometry in the…

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…

Context. Although a variety of techniques have been employed for determining the Milky Way dark matter halo mass distribution, the range of allowed masses spans both light and heavy values. Knowing the precise mass of our Galaxy is…

星系天体物理 · 物理学 2017-04-19 Giacomo Fragione , Abraham Loeb

We use a distribution function analysis to estimate the mass of the Milky Way out to 100 kpc using a large sample of halo stars. These stars are compiled from the literature, and the vast majority (~98%) have 6D phase-space information. We…

We present a spectroscopic sample of 910 distant halo stars from the Hypervelocity Star survey from which we derive the velocity dispersion profile of the Milky Way halo. The sample is a mix of 74% evolved horizontal branch stars and 26%…

星系天体物理 · 物理学 2010-07-22 Warren R. Brown , Margaret J. Geller , Scott J. Kenyon , Antonaldo Diaferio

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

Although numerous dynamical techniques have been developed to estimate the total dark matter halo mass of the Milky Way, it remains poorly constrained, with typical systematic uncertainties of 0.3 dex. In this study, we apply a neural…

星系天体物理 · 物理学 2025-10-03 Elaheh Hayati , Peter Behroozi , Ekta Patel , Yunchong Wang , Stefan Gottlöber , Gustavo Yepes

The mass of the Milky Way is a critical quantity which, despite decades of research, remains uncertain within a factor of two. Until recently, most studies have used dynamical tracers in the inner regions of the halo, relying on…

We use A-type stars selected from Sloan Digital Sky Survey data release 9 photometry to measure the outer slope of the Milky Way stellar halo density profile beyond 50 kpc. A likelihood-based analysis is employed that models the ugr…

星系天体物理 · 物理学 2015-06-19 Alis J. Deason , Vasily Belokurov , Sergey E. Koposov , Connie M. Rockosi

Blue Horizontal Branch (BHB) stars, excellent distant tracers for probing the Milky Way's halo density profile, are distinguished in the $(g-r)_0$ vs $(i-z)_0$ color space from another class of stars, blue straggler stars (BSs). We develop…

We use distant Blue Horizontal Branch stars with Galactocentric distances 16 < r/kpc < 48 as kinematic tracers of the Milky Way dark halo. We model the tracer density as an oblate, power-law embedded within a spherical power-law potential.…

星系天体物理 · 物理学 2015-06-04 A. J. Deason , V. Belokurov , N. W. Evans , J. H. An

We measure the rotation of the Milky Way stellar halo on two samples of Blue Horizontal Branch (BHB) field halo stars from the Sloan Digital Sky Survey (SDSS) with four different methods. The two samples comprise 1582 and 2563 stars…

星系天体物理 · 物理学 2015-06-15 Francesco Fermani , Ralph Schönrich

We present a family of robust tracer mass estimators to compute the enclosed mass of galaxy haloes from samples of discrete positional and kinematical data of tracers, such as halo stars, globular clusters and dwarf satellites. The data may…

星系天体物理 · 物理学 2015-05-18 L. L. Watkins , N. W. Evans , J. An

We present initial results from our study of the outer halo of the Milky Way using a large sample of RR Lyr(ab) variables datamined from the archives of the Palomar Transient Facility. Of the 464 RR Lyr in our sample with distances…

星系天体物理 · 物理学 2016-09-07 Judith G. Cohen , Branimir Sesar , Sophianna Banholzer , the PTF Consortium

The mass of the dark matter halo of the Milky Way can be estimated by fitting analytical models to the phase-space distribution of dynamical tracers. We test this approach using realistic mock stellar halos constructed from the Aquarius…

星系天体物理 · 物理学 2015-10-28 Wenting Wang , Jiaxin Han , Andrew P. Cooper , Shaun Cole , Carlos Frenk , Ben Lowing

We describe a major survey of the Milky Way halo designed to test for kinematic substructure caused by destruction of accreted satellites. We use the Washington photometric system to identify halo stars efficiently for spectroscopic…

As the Milky Way and its satellite system become more entrenched in near field cosmology efforts, the need for an accurate mass estimate of the Milky Way's dark matter halo is increasingly critical. With the second and early third data…

RR Lyr stars are ideal massless tracers that can be used to study the total mass and dark matter content of the outer halo of the Milky Way. This is because they are easy to find in the light curve databases of large stellar surveys and…

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