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Title: THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES

Abstract

We present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P {<=} 1 day) binaries. Our sample includes four objects with remarkable log g {approx_equal} 5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times <10 Gyr. Four have {approx}>0.9 M{sub Sun} companions. If the companions are massive WDs, these four binaries will evolve into stable mass transfer AM CVn systems and possibly explode as underluminous supernovae. If the companions are neutron stars, then these may be millisecond pulsar binaries. These discoveries increase the number of detached, double degenerate binaries in the ELM Survey to 54; 31 of these binaries will merge within a Hubble time.

Authors:
;  [1]; ;  [2];  [3]
  1. Smithsonian Astrophysical Observatory, 60 Garden St, Cambridge, MA 02138 (United States)
  2. Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK, 73019 (United States)
  3. Instituto de Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain)
Publication Date:
OSTI Identifier:
22126602
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 769; 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; EDGE LOCALIZED MODES; GALAXIES; GRAVITATION; MASS TRANSFER; METALS; NEUTRON STARS; NEUTRONS; PULSARS; SUPERNOVAE; SURFACES; WHITE DWARF STARS

Citation Formats

Brown, Warren R., Kenyon, Scott J., Kilic, Mukremin, Gianninas, A., and Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: callende@iac.es. THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES. United States: N. p., 2013. Web. doi:10.1088/0004-637X/769/1/66.
Brown, Warren R., Kenyon, Scott J., Kilic, Mukremin, Gianninas, A., & Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: callende@iac.es. THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES. United States. doi:10.1088/0004-637X/769/1/66.
Brown, Warren R., Kenyon, Scott J., Kilic, Mukremin, Gianninas, A., and Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: callende@iac.es. 2013. "THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES". United States. doi:10.1088/0004-637X/769/1/66.
@article{osti_22126602,
title = {THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES},
author = {Brown, Warren R. and Kenyon, Scott J. and Kilic, Mukremin and Gianninas, A. and Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: callende@iac.es},
abstractNote = {We present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P {<=} 1 day) binaries. Our sample includes four objects with remarkable log g {approx_equal} 5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times <10 Gyr. Four have {approx}>0.9 M{sub Sun} companions. If the companions are massive WDs, these four binaries will evolve into stable mass transfer AM CVn systems and possibly explode as underluminous supernovae. If the companions are neutron stars, then these may be millisecond pulsar binaries. These discoveries increase the number of detached, double degenerate binaries in the ELM Survey to 54; 31 of these binaries will merge within a Hubble time.},
doi = {10.1088/0004-637X/769/1/66},
journal = {Astrophysical Journal},
number = 1,
volume = 769,
place = {United States},
year = 2013,
month = 5
}
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