Spectroscopic study of Ba and CEMP-s stars: Mass distribution of AGB progenitors
arXiv:2212.00834 · doi:10.3847/1538-3881/aca971
Abstract
We have performed detailed high-resolution spectroscopic analysis on seven metal-poor stars (BD+75 348, BD+09 3019, HD238020, HE0319-0215, HE0507-1653, HE0930-0018, HE1023-1504) and derived their atmospheric parameters T, log, [Fe/H], and mictroturbulent velocity (). The metallicity range is found to be -2.57[Fe/H]-0.42. The elemental abundances of 17 light elements and 12 heavy elements are estimated. We have classified BD+75 348 and BD+09 3019 as strong Ba stars, HD238020 as a mild Ba star, and the remaining four objects as CEMP-s stars. We have estimated the masses of the stars from Hertzsprung-Russel (HR) diagram, and, compiling the data of 205 Ba stars from literature, estimated the mass distribution of Ba stars. We have also estimated the initial masses of the companion AGBs of the program stars as well as the masses of the companion AGBs of 159 Ba and 36 CEMP-s stars from literature, with the help of a parametric-model-based analysis using FRUITY models. While the primary mass distribution of mild Ba stars peaks at 3.7 M, for the strong Ba stars the peak appears at 2.5 M. We, therefore, propose that the initial masses of the progenitor AGBs dominantly control the formation of mild and strong Ba stars. However, a clear overlap, in the range 1.3-4.0 M, noticed between the progenitor masses of both the subclasses of Ba stars, may indicate that other factors, such as metallicities and the orbital periods, may also have significant contributions. The progenitor AGBs' mass distribution of CEMP-s stars is found to peak at 2.03 M.
35 pages, 16 figures, accepted for publication in the Astronomical Journal (AJ)
References in corpus (26)
- Carbon Enhanced Metal-Poor Stars. I. Chemical Compositions of 26 Stars
- CH in stellar atmospheres: an extensive linelist
- Super and massive AGB stars - IV. Final fates - Initial to final mass relation
- The intermediate neutron-capture process and carbon-enhanced metal-poor stars
- Binarity in Carbon-Enhanced Metal-Poor stars
- Line lists for the A2PI-X2Sigma+ (red) and {B2Sigma+-X2Sigma} (violet) Systems of CN, 13C14N, and 12C15N, and Application to Astronomical Spectra
- The Hamburg/ESO R-process Enhanced Star survey (HERES) III. HE 0338-3945 and the formation of the r+s stars
- New Extremely Metal-Poor Stars in the Galactic Halo
- Barium & related stars and their white-dwarf companions I. Giant stars
- linemake: An Atomic and Molecular Line List Generator
- A high-resolution spectral analysis of three carbon-enhanced metal-poor stars
- Analysis of 26 Barium Stars I. Abundances
- Learning about the intermediate neutron-capture process from lead abundances
- Abundances and kinematics of carbon-enhanced metal-poor stars in the Galactic halo*; A new classification scheme based on Sr and Ba
- Three-dimensional hydrodynamical simulations of mass transfer in binary systems by a free wind
- CH stars at High Galactic Latitudes
- Low-mass low-metallicity AGB stars as an efficient i-process site explaining CEMP-rs stars
- Carbon stars from LAMOST DR2 data
- Spectroscopic study of CEMP-(s & r/s) stars- Revisiting classification criteria and formation scenarios, highlighting i-process nucleosynthesis
- Barium stars as tracers of s-process nucleosynthesis in AGB stars I. 28 stars with independently derived AGB mass
- Chemical analysis of CH stars - III: Atmospheric parameters and elemental abundances
- Characterizing the companion AGBs using surface chemical composition of barium stars
- Unusual neutron-capture nucleosynthesis in a carbon-rich Galactic bulge star
- The formation of barium giants via mass accretion in binary systems
- Carbon Abundances of Three Carbon-Enhanced Metal-Poor Stars from High-Resolution Gemini-S/bHROS Spectra of the 8727A [C I] Line
- The peculiar abundances of HE 1005-1439. A carbon-enhanced extremely metal-poor star contaminated with products of both s-and i-process nucleosynthesis