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Title: DETECTION OF PHOSPHORUS, SULPHUR, AND ZINC IN THE CARBON-ENHANCED METAL-POOR STAR BD+44 493

Abstract

The carbon-enhanced metal-poor star BD+44°493 ([Fe/H] = −3.9) has been proposed as a candidate second-generation star enriched by metals from a single Pop III star. We report the first detections of P and S and the second detection of Zn in any extremely metal-poor carbon-enhanced star, using new spectra of BD+44°493 collected by the Cosmic Origins Spectrograph on the Hubble Space Telescope . We derive [P/Fe] = −0.34 ± 0.21, [S/Fe] = +0.07 ± 0.41, and [Zn/Fe] = −0.10 ± 0.24. We increase by 10-fold the number of Si i lines detected in BD+44°493, yielding [Si/Fe] = +0.15 ± 0.22. The [S/Fe] and [Zn/Fe] ratios exclude the hypothesis that the abundance pattern in BD+44°493 results from depletion of refractory elements onto dust grains. Comparison with zero-metallicity supernova (SN) models suggests that the stellar progenitor that enriched BD+44°493 was massive and ejected much less than 0.07 M {sub ⊙} of {sup 56}Ni, characteristic of a faint SN.

Authors:
 [1]; ;  [2]
  1. Department of Astronomy, University of Michigan, 1085 S. University Avenue, Ann Arbor, MI 48109 (United States)
  2. Joint Institute for Nuclear Astrophysics and Center for the Evolution of the Elements (JINA-CEE) (United States)
Publication Date:
OSTI Identifier:
22654299
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 824; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; CARBON; COMPARATIVE EVALUATIONS; DETECTION; DUSTS; HYPOTHESIS; METALLICITY; NICKEL 56; NUCLEAR REACTIONS; NUCLEOSYNTHESIS; PHOSPHORUS; REFRACTORIES; SPACE; SPECTRA; STARS; SULFUR; SUPERNOVAE; TELESCOPES; TRITIUM; ZINC

Citation Formats

Roederer, Ian U., Placco, Vinicius M., and Beers, Timothy C., E-mail: iur@umich.edu. DETECTION OF PHOSPHORUS, SULPHUR, AND ZINC IN THE CARBON-ENHANCED METAL-POOR STAR BD+44 493. United States: N. p., 2016. Web. doi:10.3847/2041-8205/824/2/L19.
Roederer, Ian U., Placco, Vinicius M., & Beers, Timothy C., E-mail: iur@umich.edu. DETECTION OF PHOSPHORUS, SULPHUR, AND ZINC IN THE CARBON-ENHANCED METAL-POOR STAR BD+44 493. United States. doi:10.3847/2041-8205/824/2/L19.
Roederer, Ian U., Placco, Vinicius M., and Beers, Timothy C., E-mail: iur@umich.edu. 2016. "DETECTION OF PHOSPHORUS, SULPHUR, AND ZINC IN THE CARBON-ENHANCED METAL-POOR STAR BD+44 493". United States. doi:10.3847/2041-8205/824/2/L19.
@article{osti_22654299,
title = {DETECTION OF PHOSPHORUS, SULPHUR, AND ZINC IN THE CARBON-ENHANCED METAL-POOR STAR BD+44 493},
author = {Roederer, Ian U. and Placco, Vinicius M. and Beers, Timothy C., E-mail: iur@umich.edu},
abstractNote = {The carbon-enhanced metal-poor star BD+44°493 ([Fe/H] = −3.9) has been proposed as a candidate second-generation star enriched by metals from a single Pop III star. We report the first detections of P and S and the second detection of Zn in any extremely metal-poor carbon-enhanced star, using new spectra of BD+44°493 collected by the Cosmic Origins Spectrograph on the Hubble Space Telescope . We derive [P/Fe] = −0.34 ± 0.21, [S/Fe] = +0.07 ± 0.41, and [Zn/Fe] = −0.10 ± 0.24. We increase by 10-fold the number of Si i lines detected in BD+44°493, yielding [Si/Fe] = +0.15 ± 0.22. The [S/Fe] and [Zn/Fe] ratios exclude the hypothesis that the abundance pattern in BD+44°493 results from depletion of refractory elements onto dust grains. Comparison with zero-metallicity supernova (SN) models suggests that the stellar progenitor that enriched BD+44°493 was massive and ejected much less than 0.07 M {sub ⊙} of {sup 56}Ni, characteristic of a faint SN.},
doi = {10.3847/2041-8205/824/2/L19},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 824,
place = {United States},
year = 2016,
month = 6
}
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