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Title: CD −24°17504 REVISITED: A NEW COMPREHENSIVE ELEMENT ABUNDANCE ANALYSIS

Abstract

With [Fe/H] ∼ −3.3, CD −24°17504 is a canonical metal-poor main-sequence turn-off star. Though it has appeared in numerous literature studies, the most comprehensive abundance analysis for the star based on high-resolution, high signal-to-noise ratio (S/N) spectra is nearly 15 years old. We present a new detailed abundance analysis for 21 elements based on combined archival Keck-HIRES and Very Large Telescope-UVES spectra of the star that is higher in both spectral resolution and S/N than previous data. Our results are very similar to those of an earlier comprehensive study of the star, but we present for the first time a carbon abundance from the CH G-band feature as well as improved upper limits for neutron-capture species such as Y, Ba, and Eu. In particular, we find that CD −24°17504 has [Fe/H] = −3.41, [C/Fe] = +1.10, [Sr/H] = −4.68, and [Ba/H] ≤ −4.46, making it a carbon-enhanced metal-poor star with neutron-capture element abundances among the lowest measured in Milky Way halo stars.

Authors:
;  [1]
  1. Kavli Institute for Astrophysics and Space Research and Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)
Publication Date:
OSTI Identifier:
22522141
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 808; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BARIUM; CARBON; ELEMENT ABUNDANCE; EUROPIUM; HYDROGEN; IRON; MAIN SEQUENCE STARS; MILKY WAY; NEUTRON REACTIONS; RESOLUTION; SIGNAL-TO-NOISE RATIO; TELESCOPES; ULTRAVIOLET SPECTRA; YTTRIUM

Citation Formats

Jacobson, Heather R., and Frebel, Anna. CD −24°17504 REVISITED: A NEW COMPREHENSIVE ELEMENT ABUNDANCE ANALYSIS. United States: N. p., 2015. Web. doi:10.1088/0004-637X/808/1/53.
Jacobson, Heather R., & Frebel, Anna. CD −24°17504 REVISITED: A NEW COMPREHENSIVE ELEMENT ABUNDANCE ANALYSIS. United States. doi:10.1088/0004-637X/808/1/53.
Jacobson, Heather R., and Frebel, Anna. 2015. "CD −24°17504 REVISITED: A NEW COMPREHENSIVE ELEMENT ABUNDANCE ANALYSIS". United States. doi:10.1088/0004-637X/808/1/53.
@article{osti_22522141,
title = {CD −24°17504 REVISITED: A NEW COMPREHENSIVE ELEMENT ABUNDANCE ANALYSIS},
author = {Jacobson, Heather R. and Frebel, Anna},
abstractNote = {With [Fe/H] ∼ −3.3, CD −24°17504 is a canonical metal-poor main-sequence turn-off star. Though it has appeared in numerous literature studies, the most comprehensive abundance analysis for the star based on high-resolution, high signal-to-noise ratio (S/N) spectra is nearly 15 years old. We present a new detailed abundance analysis for 21 elements based on combined archival Keck-HIRES and Very Large Telescope-UVES spectra of the star that is higher in both spectral resolution and S/N than previous data. Our results are very similar to those of an earlier comprehensive study of the star, but we present for the first time a carbon abundance from the CH G-band feature as well as improved upper limits for neutron-capture species such as Y, Ba, and Eu. In particular, we find that CD −24°17504 has [Fe/H] = −3.41, [C/Fe] = +1.10, [Sr/H] = −4.68, and [Ba/H] ≤ −4.46, making it a carbon-enhanced metal-poor star with neutron-capture element abundances among the lowest measured in Milky Way halo stars.},
doi = {10.1088/0004-637X/808/1/53},
journal = {Astrophysical Journal},
number = 1,
volume = 808,
place = {United States},
year = 2015,
month = 7
}
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