KINEMATICS OF THE STELLAR HALO AND THE MASS DISTRIBUTION OF THE MILKY WAY USING BLUE HORIZONTAL BRANCH STARS

@article{Kafle2012KINEMATICSOT,
  title={KINEMATICS OF THE STELLAR HALO AND THE MASS DISTRIBUTION OF THE MILKY WAY USING BLUE HORIZONTAL BRANCH STARS},
  author={Prajwal R Kafle and Sanjib Sharma and Geraint F. Lewis and Joss Bland-Hawthorn},
  journal={The Astrophysical Journal},
  year={2012},
  volume={761},
  pages={98}
}
Here we present a kinematic study of the Galactic halo out to a radius of ∼ 60 kpc, using 4664 blue horizontal branch (BHB) stars selected from the SDSS/SEGUE survey, to determine key dynamical properties. Using a maximum likelihood analysis, we determine the velocity dispersion profiles in spherical coordinates ( �r, ��, ��) and the anisotropy profile ( �). The radial velocity dispersion profile ( �r) is measured out to a galactocentric radius of r ∼ 60 kpc, but due to the lack of proper… Expand
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References

SHOWING 1-10 OF 108 REFERENCES
A Dynamical and Kinematic Model of the Galactic Stellar Halo and Possible Implications for Galaxy Formation Scenarios
We reanalyze the kinematics and dynamics of the system of blue horizontal-branch field (BHBF) stars in the Galactic halo (in particular the outer halo), fitting the kinematics with the model ofExpand
THE MASS PROFILE OF THE GALAXY TO 80 kpc
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 theExpand
The radial velocity dispersion profile of the Galactic halo : constraining the density profile of the dark halo of the Milky Way
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 (FHB) starsExpand
The Milky Way Tomography with SDSS: III. Stellar Kinematics
We study Milky Way kinematics using a sample of 18.8 million main-sequence stars with r 20°). We find that in the region defined by 1 kpc <Z< 5 kpc and 3 kpc <R< 13 kpc, the rotational velocity forExpand
The Milky Way stellar halo out to 40 kpc: squashed, broken but smooth
We introduce a new maximum-likelihood method to model the density profile of blue horizontal branch and blue straggler stars and apply it to the Sloan Digital Sky Survey Data Release 8 photometricExpand
Velocity Dispersion Profile of the Milky Way Halo
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%Expand
Broken degeneracies: the rotation curve and velocity anisotropy of the Milky Way halo
We use distant blue horizontal branch stars with Galactocentric distances 16 < r < 48 kpc as kinematic tracers of the Milky Way dark halo. We model the tracer density as an oblate, power law embeddedExpand
MAPPING THE GALACTIC HALO WITH BLUE HORIZONTAL BRANCH STARS FROM THE TWO-DEGREE FIELD QUASAR REDSHIFT SURVEY
We use 666 blue horizontal branch stars from the 2Qz Redshift Survey to map the Galactic halo in four dimensions (position, distance, and velocity). We find that the halo extends to at least 100 kpcExpand
The Milky Way’s Circular Velocity Curve to 60 kpc and an Estimate of the Dark Matter Halo Mass from the Kinematics of ~2400 SDSS Blue Horizontal-Branch Stars
We derive new constraints on the mass of the Milky Way's dark matter halo, based on 2401 rigorously selected blue horizontal-branch halo stars from SDSS DR6. This sample enables construction of theExpand
Kinematic Structure in the Galactic Halo at the North Galactic Pole: RR Lyrae and BHB Stars show different kinematics
Space motions are given for 38 RR Lyrae (RRL) stars and 79 blue horizontal branch (BHB) stars in a ~200 deg2 area around the North Galactic Pole (NGP) using a homogeneous distance scale consistentExpand
...
1
2
3
4
5
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