Related papers: The most metal poor stars
The chemical abundance patterns observed in metal-poor Galactic halo stars contain the signature of the first supernovae, and thus allows us to probe the first stars that formed in the universe. We construct a theoretical model for the…
Carbon-enhanced metal poor stars (CEMP) form a significant proportion of the metal-poor stars, their origin is not well understood. Three very metal-poor C-rich turnoff stars were selected from the SDSS survey, observed with the ESO VLT…
We construct three extreme different scenarios of the star formation histories applicable to a sample of dwarf galaxies, based either on their present metallicity or their luminosity. The three possible scenarios imply different mechanical…
The metal content of planet hosting stars is an important ingredient which may affect the formation and evolution of planetary systems. Accurate stellar abundances require the determinations of reliable physical parameters, namely the…
We present initial results measuring the companion fraction of metal-poor stars ([Fe/H]$<-$2.0). We are employing the Lick Observatory planet-finding system to make high-precision Doppler observations of these objects. The binary fraction…
We have undertaken a spectroscopic survey of field stars to find metal-poor objects among them. Observations are carried out using OMR spectrograph attached to 2.3m telescope at VBO Kavalur, India. The sample of candidate stars are chosen…
The abundance patterns of metal-poor stars provide us a wealth of chemical information about various stages of the chemical evolution of the Galaxy. In particular, these stars allow us to study the formation and evolution of the elements…
We compare elemental abundance patterns of $\sim 200$ extremely metal-poor (EMP; [Fe/H]$<-3$) stars with supernova yields of metal-free stars in order to obtain insights into the characteristic masses of the first (Population III or Pop…
The Neptune desert is no longer empty. A handful of close-in planets with masses between those of Neptune and Saturn have now been discovered, and their puzzling properties have inspired a number of interesting theories on the formation and…
Stellar metallicity -- as a probe of the metallicity of proto-planetary disks -- is an important ingredient for giant planet formation, likely through its effect on the timescales in which rocky/icy planet cores can form. Giant planets have…
Low metallicity stars give rise to unique spectacular transients and are of immense interest for understanding stellar evolution. Their importance has only grown further with the recent detections of mergers of stellar mass black holes that…
The low-mass metal-poor stars in the Galaxy that preserve in their atmosphere, the chemical imprints of the gas clouds from which they were formed can be used as probes to get insight into the origin and evolution of elements in the early…
The first stars in the Universe are predicted to have been much more massive than the Sun. Gravitational condensation accompanied by cooling of the primordial gas due to molecular hydrogen, yields a minimum fragmentation scale of a few…
We calculate the mean evolution of the iron-peak abundance ratios [(Cr,Mn,Co,Zn)/Fe] in the Galaxy, using modern supernova and hypernova chemical yields and a Galactic Chemical Evolution code that assumes homogeneous chemical evolution. We…
(Abbreviated) We present a detailed analysis of the space motions of 1203 solar-neighborhood stars with metal abundances [Fe/H] <= -0.6, on the basis of a recently revised and supplemented catalog of metal-poor stars selected without…
Several emerging links between high-redshift observational cosmology and the Galactic fossil evidence found in the kinematics, metallicities and ages of Milky Way stars are discussed. In a flat Cold Dark Matter model with $\Omega\simeq 0.3$…
The oldest stars in the universe retain to a great extent detailed information on the chemical composition of the interstellar medium at the time of their birth. Hence the earliest phases of Galactic chemical evolution and nucleosynthesis…
Metallicity is a fundamental physical property that strongly constrains galaxy formation and evolution. The formation of stars in galaxies is suppressed by the energy released from supernova explosions and can be enhanced by metal…
We utilize Sloan Digital Sky Survey imaging and spectroscopy of ~53,000 star-forming galaxies at z~0.1 to study the relation between stellar mass and gas-phase metallicity. We derive gas-phase oxygen abundances and stellar masses using new…
We combine star-formation histories derived from observations of high redshift galaxies with measurements of the z~0 relation between gas-phase metallicity, stellar mass, and star formation rate to make an explicit and completely empirical…