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Related papers: Extremely metal-poor stars in SDSS fields

200 papers

Based on high resolution and high signal-to-noise ratio (S/N) spectra analysis of 90 solar type stars, we have established several new metallicity calibrations in Teff range [5600, 6500] K based on red spectra with the wavelength range of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 J. K. Zhao , G. Zhao , Y. Q. Chen , A. L. Luo

We examine the correlation between stellar metallicity and short period planets. It appears that approximately 1% of dwarf stars in the solar neighborhood harbor short-period planets characterized by near-circular orbits and orbital periods…

Astrophysics · Physics 2009-10-31 Gregory Laughlin

We present a statistical parallax study of nearly 2,000 M subdwarfs with photometry and spectroscopy from the Sloan Digital Sky Survey. Statistical parallax analysis yields the mean absolute magnitudes, mean velocities and velocity…

Solar and Stellar Astrophysics · Physics 2015-06-12 John J. Bochanski , Antonia Savcheva , Andrew A. West , Suzanne L. Hawley

We report the discovery of a peculiar set of old super-metal-rich dwarf stars with orbits of low eccentricity that reach a maximum height from the Galactic plane between $\sim$ 0.5-1.5 kpc observed by the \emph{Gaia}-ESO Survey. These stars…

Solar and Stellar Astrophysics · Physics 2025-01-29 M. L. L. Dantas , R. Smiljanic , R. Boesso , H. Rocha-Pinto , L. Magrini , G. Guiglion , D. Romano

Metal-poor stars are a rare and ancient type of stars; Carbon-Enhanced Metal-Poor (CEMP) stars are a subset of these celestial bodies that show an enrichment of carbon relative to iron. They are believed to be formed from gas polluted by…

Solar and Stellar Astrophysics · Physics 2025-05-09 Ziyu Fang , Xiangru Li , Haining Li

We obtain estimates of stellar atmospheric parameters for a previously published sample of 1777 relatively bright (9 < B < 14) metal-poor candidates from the Hamburg/ESO Survey. The original Frebel et al. analysis of these stars was only…

Abundance ratios in extremely metal-poor (EMP) stars are a good indication of the chemical composition of the gas in the earliest phases of the Galaxy evolution. It had been found from an LTE analysis that at low metallicity, and in…

Astrophysics · Physics 2009-11-13 S. M. Andrievsky , M. Spite , S. A. Korotin , F. Spite , P. Bonifacio , R. Cayrel , V. Hill , P. Francois

We derive a sample of 114 Baldwin-Phillips-Terlevich diagram - star formation (BPT-SF) and Wide-field infrared Survey Exploer - low star formation rate (WISE-LSFR) early-type galaxies (ETGs) by utilizing the criterion W2-W3$<2.5$ (where W2…

Astrophysics of Galaxies · Physics 2024-10-08 Wu Yu-zhong , Zhang Wei

A substantial fraction of metal-poor stars in the local Milky Way halo exhibit large overabundances of carbon. These stars, dubbed Carbon-Enhanced Metal-Poor (CEMP) stars, provide crucial constraints on the nature of the early universe…

The first stars are predicted to have formed within 200 million years after the Big Bang, initiating the cosmic dawn. A true first star has not yet been discovered, although stars with tiny amounts of elements heavier than helium ('metals')…

The most metal-poor stars found in the Galaxy and in nearby galaxies are witnesses of the early evolution of the Universe. In a general picture in which we expect the metallicity to increase monotonically with time, as a result of the metal…

Astrophysics of Galaxies · Physics 2025-05-30 P. Bonifacio , E. Caffau , P. François , M. Spite

In this work we combine spectroscopic information from the \textit{SkyMapper survey for Extremely Metal-Poor stars} and astrometry from Gaia DR2 to investigate the kinematics of a sample of 475 stars with a metallicity range of $ -6.5 \leq…

We present a catalog of 8,440 candidate very metal-poor (VMP; [Fe/H] < -2.0) main-sequence turn-off (MSTO) and red giant stars in the Milky Way, identified from low-resolution spectra in LAMOST DR10. More than 7,000 of these candidates are…

Astrophysics of Galaxies · Physics 2025-06-12 Xiangyu Li , Huiling Chen , Yang Huang , Huawei Zhang , Timothy C. Beers , Linxuan Zhu , Jifeng Liu

We use data for 6048 early-type galaxies (ETGs) from Galaxy Zoo 1 that have been cross-matched with the catalog of the MPA-JHU emission-line measurements for the Sloan Digital Sky Survey Data Release 7. We measure the metallicity of these…

Astrophysics of Galaxies · Physics 2021-12-20 Wu Yuzhong

A metal-rich environment facilitates planet formation, making metal-rich stars the most favorable targets for surveys seeking to detect new exoplanets. Using this advantage to identify likely low-mass planet hosts, however, has been…

Solar and Stellar Astrophysics · Physics 2012-03-15 Barbara Rojas-Ayala , Kevin R. Covey , Philip S. Muirhead , James P. Lloyd

In this work, we present high-resolution spectroscopic observations for six metal-poor stars with [Fe/H]<-3 (including one with [Fe/H]<-4), selected using narrow-band Ca II HK photometry from the DECam MAGIC Survey. The spectroscopic data…

Extremely metal poor (EMP) stars in the Milky Way inherited the chemical composition of the gas out of which they formed. They therefore carry the chemical fingerprint of the first stars in their spectral lines. It is commonly assumed that…

Astrophysics of Galaxies · Physics 2018-10-24 Tilman Hartwig , Miho N. Ishigaki , Ralf S. Klessen , Naoki Yoshida

We find that Kepler exoplanet candidate (EC) host stars are preferentially metal-rich, including the low-mass stellar hosts of small-radius ECs. The last observation confirms a tentative hint that there is a correlation between the…

Earth and Planetary Astrophysics · Physics 2015-05-28 Kevin C. Schlaufman , Gregory Laughlin

CONTEXT:The detailed chemical abundances of extremely metal-poor (EMP) stars are key guides to understanding the early chemical evolution of the Galaxy. Most existing data are, however, for giant stars which may have experienced internal…