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相关论文: The Asymmetric Thick Disk: A Star Count and Kinema…

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In the first two papers of this series, Larsen et al (2010a,b) describe our faint CCD survey in the inner Galaxy and map the over-density of Thick Disk stars in Quadrant I (Q1) to 5 kpc or more along the line of sight. The regions showing…

A significant asymmetry in the distribution of faint blue stars in the inner Galaxy, Quadrant 1 (l = 20 to 45 degrees) compared to Quadrant 4 was first reported by Larsen & Humphreys (1996). Parker et al (2003, 2004) greatly expanded the…

星系天体物理 · 物理学 2014-11-20 J. A. Larsen , J. E. Cabanela , R. M. Humphreys , A. P. Haviland

We study the kinematics of a local sample of stars, located within a cylinder of 500 pc radius centered on the Sun, in the RAVE dataset. We find clear asymmetries in the $v_R$-$v_\phi$ velocity distributions of thin and thick disk stars:…

The stellar asymmetry of faint thick disk/inner halo stars in the first quadrant first reported by Larsen & Humphreys (1996) and investigated further by Parker et al. (2003, 2004) has been recently confirmed by SDSS (Juric et al. 2008).…

天体物理学 · 物理学 2009-11-13 Jeffrey A. Larsen , Roberta M. Humphreys , Juan E. Cabanela

We study the kinematics of the Galactic thin and thick disk populations using stars from the RAVE survey's second data release together with distance estimates from Breddels et al. (2009). The velocity distribution exhibits the expected…

星系天体物理 · 物理学 2015-05-27 Yüksel Karatas , Rainer J. Klement

Based on the LAMOST survey and Sloan Digital Sky Survey (SDSS), we use low-resolution spectra of 130,043 F/G-type dwarf stars to study the kinematics and metallicity properties of the Galactic disk. Our study shows that the stars with…

Nearly 400 Tycho-2 stars have been observed in a 720 square degree field in the direction of the North Galactic Pole with the high resolution echelle spectrograph ELODIE. Absolute magnitudes, effective temperatures, gravities and…

天体物理学 · 物理学 2009-11-07 C. Soubiran , O. Bienaymé , A. Siebert

Full space velocities are computed for a sample of 130 nearby RR Lyrae variables using both ground-based and Hipparcos proper motions. In many cases proper motions from multiple sources have been averaged to produce a significant…

天体物理学 · 物理学 2009-10-30 John C. Martin , Heather L. Morrison

We have analysed the kinematics of a sample of 114 hot subdwarf stars, for 2/3 of which we present new proper motions, spectroscopic and photometric data. The vast majority of the stars show a kinematic behaviour that is similar to that of…

天体物理学 · 物理学 2008-11-26 M. Altmann , H. Edelmann , K. S. de Boer

We analyze a new kinematic survey that includes accurate proper motions derived from SDSS DR7 positions, combined with multi-epoch measurements from the GSC-II database. By means of the SDSS spectro-photometric data (effective temperature,…

星系天体物理 · 物理学 2015-05-18 A. Spagna , M. G. Lattanzi , P. Re Fiorentin , R. L. Smart

The kinematics of the stellar halo hold important clues to the assembly history and mass distribution of the Galaxy. In this study, we map the kinematics of stars across the Galactic halo with the H3 Survey. We find a complex distribution…

We analyze the 3D kinematics of a sample of $\sim 4400$ red clump stars ranging between 5 and 10 kpc from the Galactic center and up to 3 kpc from the Galactic plane. This sample is representative for the metal-rich ([Fe/H] = -0.6 to 0.5)…

星系天体物理 · 物理学 2015-05-20 D. I. Casetti-Dinescu , T. M. Girard , V. I. Korchagin , W. F van Altena

We study Milky Way kinematics using a sample of 18.8 million main-sequence stars with r<20 and proper-motion measurements derived from SDSS and POSS astrometry, including ~170,000 stars with radial-velocity measurements from the SDSS…

星系天体物理 · 物理学 2014-11-20 N. A. Bond , Z. Ivezic , B. Sesar , M. Juric , J. Munn

[Abridged] We present a medium-resolution spectroscopic survey of late-type giant stars at mid-Galactic latitudes of (30$^{\circ}<|b|<60^{\circ}$), designed to probe the properties of this population to distances of $\sim$9 kpc. Because M…

Based on the second Gaia data release (DR2), combined with the LAMOST and APOGEE spectroscopic surveys, we study the kinematics and metallicity distribution of the high-velocity stars that have a relative speed of at least 220 ${\rm km\…

星系天体物理 · 物理学 2020-11-18 Yepeng Yan , Cuihua Du , Hefan Li , Jianrong Shi , Jun Ma , Heidi Jo Newberg

We determined the chemical and kinematic properties of the Galactic thin and thick disk using a sample of 307,246 A/F/G/K-type giant stars from the LAMOST spectroscopic survey and Gaia DR2 survey. Our study found that the thick disk…

星系天体物理 · 物理学 2019-07-31 Yepeng Yan , Cuihua Du , Shuai Liu , Hefan Li , Jianrong Shi , Yuqin Chen , Jun Ma , Zhenyu Wu

We performed a spectroscopic survey of nearly 700 stars probing the galactic thick disc far from the solar neighbourhood towards the galactic coordinates (l~277, b~47). The derived effective temperatures, surface gravities and overall…

We analyse a 10,000 star spectroscopic survey, focused on Galactic thick disk stars typically 2-5 kpc from the Sun, carried out using the AAOmega Spectrograph on the AAT. We develop methods for completeness-correction of the survey based on…

星系天体物理 · 物理学 2015-06-15 Apoorva Jayaraman , Gerard Gilmore , Rosemary F. G. Wyse , John E. Norris , Vasily Belokurov

We analyze the distribution of G and K type stars towards the Galactic poles using RAVE and ELODIE radial velocities, 2MASS photometric star counts, and UCAC2 proper motions. The combination of photometric and 3D kinematic data allows us to…

We present an analysis of the space motions of 742 subdwarf stars based on the sample of Carney et al. (1994, CLLA). Hipparcos parallaxes, TYC2+HIP proper motions and Tycho2 proper motions were combined with radial velocities and…

天体物理学 · 物理学 2009-11-10 M. I. Arifyanto , B. Fuchs , H. Jahreiss , R. Wielen
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