Back to Search
Start Over
The R-Process Alliance: The Peculiar Chemical Abundance Pattern of RAVE J183013.5-455510
- Publication Year :
- 2020
-
Abstract
- We report on the spectroscopic analysis of RAVE J183013.5-455510, an extremely metal-poor star, highly enhanced in CNO, and with discernible contributions from the rapid neutron-capture process. There is no evidence of binarity for this object. At [Fe/H]=-3.57, this is one of the lowest metallicity stars currently observed, with 18 measured abundances of neutron-capture elements. The presence of Ba, La, and Ce abundances above the Solar System r-process predictions suggest that there must have been a non-standard source of r-process elements operating at such low metallicities. One plausible explanation is that this enhancement originates from material ejected at unusually fast velocities in a neutron star merger event. We also explore the possibility that the neutron-capture elements were produced during the evolution and explosion of a rotating massive star. In addition, based on comparisons with yields from zero-metallicity faint supernova, we speculate that RAVE J1830-4555 was formed from a gas cloud pre-enriched by both progenitor types. From analysis based on Gaia DR2 measurements, we show that this star has orbital properties similar to the Galactic metal-weak thick-disk stellar population.<br />Accepted for publication in ApJ
- Subjects :
- 010504 meteorology & atmospheric sciences
Stellar population
Metallicity
FOS: Physical sciences
Astrophysics
Astrophysics::Cosmology and Extragalactic Astrophysics
01 natural sciences
0103 physical sciences
Astrophysics::Solar and Stellar Astrophysics
010303 astronomy & astrophysics
Stellar evolution
Solar and Stellar Astrophysics (astro-ph.SR)
Astrophysics::Galaxy Astrophysics
0105 earth and related environmental sciences
Physics
Astronomy and Astrophysics
Astrophysics - Astrophysics of Galaxies
Abundance of the chemical elements
Neutron star
Stars
Supernova
Astrophysics - Solar and Stellar Astrophysics
13. Climate action
Space and Planetary Science
Astrophysics of Galaxies (astro-ph.GA)
r-process
Astrophysics::Earth and Planetary Astrophysics
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Accession number :
- edsair.doi.dedup.....3f064c124a7a032e9b90e779f6cad7d4