Post Common Envelope Pre-Cataclysmic and Cataclysmic Variable Binaries

Persistent Link:
http://hdl.handle.net/10150/194761
Title:
Post Common Envelope Pre-Cataclysmic and Cataclysmic Variable Binaries
Author:
Sing, David Kent
Issue Date:
2005
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Extensive photometric and spectroscopic observations have been obtained for the binary HS1136+6646, a newly formed post-common envelope binary system containing a hot ~DAO.5 primary and a highly irradiated secondary. H1136+6646 is the most extreme example yet of a class of short period systems containing a hot H-rich white dwarf with a K-M companion. An orbital period of 0.83607(3) days has been determined through the phasing of radial velocities, emission line equivalent widths, and photometric measurements spanning a range of 24 months. Radial velocity measurements yield an amplitude of K_WD = 69(2) km s^-1 for the white dwarf and K_K7V = 115 +/- 1 km s^-1 for the secondary star. Photometric measurements revealed a low amplitude modulation with a period of 234 minutes, associated with the rotation of the white dwarf. The white dwarf is estimated to have an effective temperature and gravity of ~100,000 K and log g~8.29 respectively, indicating the binary system is the second earliest post-CE objects known, having an age around 6.4x10^5 years. Indications are that the secondary star is overly luminous for its mass.I also present FUSE observations of the magnetic cataclysmic variable V405 Aurigae. Together with four other DQ Her type binaries, V405 Aur forms a small subclass of intermediate polars which are likely to evolve into low magnetic field strength polars. The FUSE spectrum exhibits broad O VI and C III emission-lines as well as a narrow O VI emission-line component which likely forms near the white dwarf surface in an optically thin gas. Radial velocity measurements restrict any orbital modulation to a very low amplitude (K_WD = 2.5(0.5) km s^-1) indicating that the binary system is at low inclination.Recent photometric and spectroscopic observations have revealed J0644+3344 to be a bright, deeply eclipsing cataclysmic variable binary with a 6.46488(24) hour period. Although the nature of the hot component is not presently clear, J0644+3344 is one of the brightest eclipsing nova-like cataclysmic variable system yet. As such, the possibility exists for an unambiguous determination of the masses and temperatures of both components in future studies.
Type:
text; Electronic Dissertation
Keywords:
white dwarf; cataclysmic variables; ultraviolet - stars; spectroscopic binaries
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Physics; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Holberg, Jay B.
Committee Chair:
Holberg, Jay B.

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titlePost Common Envelope Pre-Cataclysmic and Cataclysmic Variable Binariesen_US
dc.creatorSing, David Kenten_US
dc.contributor.authorSing, David Kenten_US
dc.date.issued2005en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractExtensive photometric and spectroscopic observations have been obtained for the binary HS1136+6646, a newly formed post-common envelope binary system containing a hot ~DAO.5 primary and a highly irradiated secondary. H1136+6646 is the most extreme example yet of a class of short period systems containing a hot H-rich white dwarf with a K-M companion. An orbital period of 0.83607(3) days has been determined through the phasing of radial velocities, emission line equivalent widths, and photometric measurements spanning a range of 24 months. Radial velocity measurements yield an amplitude of K_WD = 69(2) km s^-1 for the white dwarf and K_K7V = 115 +/- 1 km s^-1 for the secondary star. Photometric measurements revealed a low amplitude modulation with a period of 234 minutes, associated with the rotation of the white dwarf. The white dwarf is estimated to have an effective temperature and gravity of ~100,000 K and log g~8.29 respectively, indicating the binary system is the second earliest post-CE objects known, having an age around 6.4x10^5 years. Indications are that the secondary star is overly luminous for its mass.I also present FUSE observations of the magnetic cataclysmic variable V405 Aurigae. Together with four other DQ Her type binaries, V405 Aur forms a small subclass of intermediate polars which are likely to evolve into low magnetic field strength polars. The FUSE spectrum exhibits broad O VI and C III emission-lines as well as a narrow O VI emission-line component which likely forms near the white dwarf surface in an optically thin gas. Radial velocity measurements restrict any orbital modulation to a very low amplitude (K_WD = 2.5(0.5) km s^-1) indicating that the binary system is at low inclination.Recent photometric and spectroscopic observations have revealed J0644+3344 to be a bright, deeply eclipsing cataclysmic variable binary with a 6.46488(24) hour period. Although the nature of the hot component is not presently clear, J0644+3344 is one of the brightest eclipsing nova-like cataclysmic variable system yet. As such, the possibility exists for an unambiguous determination of the masses and temperatures of both components in future studies.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectwhite dwarfen_US
dc.subjectcataclysmic variablesen_US
dc.subjectultraviolet - starsen_US
dc.subjectspectroscopic binariesen_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplinePhysicsen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorHolberg, Jay B.en_US
dc.contributor.chairHolberg, Jay B.en_US
dc.contributor.committeememberShupe, Michaelen_US
dc.contributor.committeememberFang, Li-Zhien_US
dc.contributor.committeememberLiebert, Jamesen_US
dc.contributor.committeememberBickel, Williamen_US
dc.identifier.proquest1400en_US
dc.identifier.oclc137355457en_US
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