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Title: A PILOT SEARCH FOR EVIDENCE OF EXTRASOLAR EARTH-ANALOG PLATE TECTONICS

Abstract

Relative to calcium, both strontium and barium are markedly enriched in Earth's continental crust compared to the basaltic crusts of other differentiated rocky bodies within the solar system. Here, we both re-examine available archived Keck spectra to place upper bounds on n(Ba)/n(Ca) and revisit published results for n(Sr)/n(Ca) in two white dwarfs that have accreted rocky planetesimals. We find that at most only a small fraction of the pollution is from crustal material that has experienced the distinctive elemental enhancements induced by Earth-analog plate tectonics. In view of the intense theoretical interest in the physical structure of extrasolar rocky planets, this search should be extended to additional targets.

Authors:
; ;  [1];  [2]
  1. Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1562 (United States)
  2. Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095 (United States)
Publication Date:
OSTI Identifier:
22365281
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 791; 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; BARIUM; CALCIUM; COMPARATIVE EVALUATIONS; CONTINENTAL CRUST; PLANETS; PLATE TECTONICS; SATELLITES; SOLAR SYSTEM; STRONTIUM; WHITE DWARF STARS

Citation Formats

Jura, M., Klein, B., Xu, S., and Young, E. D., E-mail: jura@astro.ucla.edu, E-mail: kleinb@astro.ucla.edu, E-mail: sxu@astro.ucla.edu, E-mail: eyoung@ess.ucla.edu. A PILOT SEARCH FOR EVIDENCE OF EXTRASOLAR EARTH-ANALOG PLATE TECTONICS. United States: N. p., 2014. Web. doi:10.1088/2041-8205/791/2/L29.
Jura, M., Klein, B., Xu, S., & Young, E. D., E-mail: jura@astro.ucla.edu, E-mail: kleinb@astro.ucla.edu, E-mail: sxu@astro.ucla.edu, E-mail: eyoung@ess.ucla.edu. A PILOT SEARCH FOR EVIDENCE OF EXTRASOLAR EARTH-ANALOG PLATE TECTONICS. United States. doi:10.1088/2041-8205/791/2/L29.
Jura, M., Klein, B., Xu, S., and Young, E. D., E-mail: jura@astro.ucla.edu, E-mail: kleinb@astro.ucla.edu, E-mail: sxu@astro.ucla.edu, E-mail: eyoung@ess.ucla.edu. Wed . "A PILOT SEARCH FOR EVIDENCE OF EXTRASOLAR EARTH-ANALOG PLATE TECTONICS". United States. doi:10.1088/2041-8205/791/2/L29.
@article{osti_22365281,
title = {A PILOT SEARCH FOR EVIDENCE OF EXTRASOLAR EARTH-ANALOG PLATE TECTONICS},
author = {Jura, M. and Klein, B. and Xu, S. and Young, E. D., E-mail: jura@astro.ucla.edu, E-mail: kleinb@astro.ucla.edu, E-mail: sxu@astro.ucla.edu, E-mail: eyoung@ess.ucla.edu},
abstractNote = {Relative to calcium, both strontium and barium are markedly enriched in Earth's continental crust compared to the basaltic crusts of other differentiated rocky bodies within the solar system. Here, we both re-examine available archived Keck spectra to place upper bounds on n(Ba)/n(Ca) and revisit published results for n(Sr)/n(Ca) in two white dwarfs that have accreted rocky planetesimals. We find that at most only a small fraction of the pollution is from crustal material that has experienced the distinctive elemental enhancements induced by Earth-analog plate tectonics. In view of the intense theoretical interest in the physical structure of extrasolar rocky planets, this search should be extended to additional targets.},
doi = {10.1088/2041-8205/791/2/L29},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 791,
place = {United States},
year = {Wed Aug 20 00:00:00 EDT 2014},
month = {Wed Aug 20 00:00:00 EDT 2014}
}
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