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Related papers: The SEGUE K Giant Survey. III. Quantifying Galacti…

200 papers

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…

Astrophysics of Galaxies · Physics 2015-06-19 Alis J. Deason , Vasily Belokurov , Sergey E. Koposov , Connie M. Rockosi

In L\"ovdal et al, we presented a data-driven method for clustering in Integrals of Motion space and applied it to a large sample of nearby halo stars with 6D phase-space information. We identified a large number of clusters, many of which…

Astrophysics of Galaxies · Physics 2022-09-14 Tomás Ruiz-Lara , Tadafumi Matsuno , S. Sofie Lövdal , Amina Helmi , Emma Dodd , Helmer H. Koppelman

We use Canada-France-Hawaii Telescope Legacy Survey data for 170 deg^2, recalibrated and transformed to the Sloan Digital Sky Survey ugri photometric system, to study the distribution of near-turnoff main-sequence stars in the Galactic halo…

Astrophysics of Galaxies · Physics 2015-05-20 Branimir Sesar , Mario Juric , Zeljko Ivezic

In the $\Lambda$CDM paradigm the Galactic stellar halo is predicted to harbor the accreted debris of smaller systems. To identify these systems, the H3 Spectroscopic Survey, combined with $Gaia$, is gathering 6D phase-space and chemical…

AIMS. We derive the morphology of the stellar component in the outer halo volume, and search for possible overdensities due to substructures therein. METHODS. We made use of some of the data releases of the spectroscopic survey LAMOST…

Astrophysics of Galaxies · Physics 2024-02-09 M. Lopez-Corredoira , X. -C. Tang , H. Tian , H. -F. Wang , G. Carraro , C. Liu

We fit an Extended Distribution Function (EDF) to K giants in the Sloan Extension for Galactic Understanding and Exploration (SEGUE) survey. These stars are detected to radii ~80 kpc and span a wide range in [Fe/H]. Our EDF, which depends…

Astrophysics of Galaxies · Physics 2016-05-25 Payel Das , James Binney

We present an improved analysis of halo substructure traced by RR Lyrae stars in the SDSS stripe 82 region. With the addition of SDSS-II data, a revised selection method based on new ugriz light curve templates results in a sample of 483 RR…

The latest results of the QUEST survey for RR Lyrae stars are described. This survey, which is designed to find and characterize sub-structures in the halo of our Galaxy, has covered about 700 square degrees of the sky and has detected 693…

Astrophysics · Physics 2007-05-23 A. Katherina Vivas , R. Zinn , Y. Subero , J. Hernandez

Stellar streams originating in disrupted dwarf galaxies and star clusters are observed around the Milky Way and nearby galaxies. Such substructures are the important tracers that record how the host haloes have accreted progenitor galaxies.…

Astrophysics of Galaxies · Physics 2019-05-29 Yu Morinaga , Tomoaki Ishiyama , Takanobu Kirihara , Kazuki Kinjo

Motivated by the vast gap between photometric and spectroscopic data volumes, there is great potential in using 5D kinematic information to identify and study substructures of the Milky Way. We identify substructures in the Galactic halo…

We measure the enclosed Milky Way mass profile to Galactocentric distances of $\sim70$ and $\sim50$ kpc using the smooth, diffuse stellar halo samples of Bird et al. The samples are LAMOST and SDSS/SEGUE K giants (KG) and SDSS/SEGUE blue…

Astrophysics of Galaxies · Physics 2026-01-14 Sarah A. Bird , Xiang-Xiang Xue , Chao Liu , Chris Flynn , Juntai Shen , Jie Wang , Chengqun Yang , Meng Zhai , Ling Zhu , Gang Zhao , Hai-Jun Tian

We use 666 blue horizontal branch (BHB) 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 kpc in Galactocentric distance, and…

Astrophysics of Galaxies · Physics 2015-05-19 Roberto De Propris , Craig D. Harrison , Peter J. Mares , CTIO , Cornell University

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…

We present an analysis of the relative age distribution of the Milky Way halo, based on samples of blue horizontal-branch (BHB) stars obtained from the Panoramic Survey Telescope and Rapid Response System and \textit{Galaxy Evolution…

If the stellar halos of disk galaxies are built up from the disruption of dwarf galaxies, models predict highly structured variations in the stellar populations within these halos. We test this prediction by studying the ratio of blue…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Eric F. Bell , Xiang Xiang Xue , Hans-Walter Rix , Christine Ruhland , David W. Hogg

We propose and test a method for applying statistical photometric parallax to main sequence turn off (MSTO) stars in the Sloan Digital Sky Survey (SDSS). Using simulated data, we show that if our density model is similar to the actual…

Astrophysics of Galaxies · Physics 2018-10-10 Jake Weiss , Heidi Jo Newberg , Matthew Newby , Travis Desell

The radial number density and flattening of the Milky Way's stellar halo is measured with $\mathrm{5351}$ metal-poor ([Fe/H]$<-1$) K giants from LAMOST DR3, using a nonparametric method which is model independent and largely avoids the…

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,…

Astrophysics · Physics 2007-05-23 L. Clewley , S. J. Warren , P. C. Hewett , M. Wilkinson , W. N. Evans

We present a new, high-resolution chronographic (age) map of the Milky Way's halo, based on the inferred ages of ~130,000 field blue horizontal-branch (BHB) stars with photometry from the Sloan Digital Sky Survey. Our map exhibits a strong…

Astrophysics of Galaxies · Physics 2016-09-08 D. Carollo , T. C. Beers , V. M. Placco , R. M. Santucci , P. Denissenkov , P. B. Tissera , G. Lentner , S. Rossi , Y. S. Lee , J. Tumlinson

We use the SDSS-Gaia Catalogue to identify six new pieces of halo substructure. SDSS-Gaia is an astrometric catalogue that exploits SDSS data release 9 to provide first epoch photometry for objects in the Gaia source catalogue. We use a…

Astrophysics of Galaxies · Physics 2018-01-25 G. C. Myeong , N. W. Evans , V. Belokurov , N. C. Amorisco , S. Koposov