NOAO >   Observing Info >   Approved Programs >   2013B-0004

Small NOAO Logo

Proposal Information for 2013B-0004


PI: Mukremin Kilic, University of Oklahoma, kilic@ou.edu
Address: Physics Department, 440 W Brooks Street, Norman, OK 73019, USA

CoI: J. J. Hermes, University of Texas
CoI: Alexandros Gianninas, University of Oklahoma
CoI: Warren Brown, SAO

Title: A Search for Pulsating White Dwarf Companions to Millisecond Pulsars

Abstract: We have recently discovered the first pulsating extremely low mass white dwarfs, with masses <=0.25M_\odot. These are by far the coolest and the lowest-mass pulsating white dwarfs, with temperatures of 8500-10,000 K and \log g=6-7. These stars greatly extend the DAV (or ZZ Ceti) instability strip, effectively bridging the gap in \log g between white dwarfs and main-sequence stars. Curiously, there are two spectroscopically confirmed white dwarf companions to millisecond pulsars that have similar temperature and surface gravity measurements as this newly discovered class of pulsators. To search for pulsations, here we propose to obtain Gemini GMOS time-series photometry of the white dwarf companions to these two millisecond pulsars. If they pulsate, these will be the first known examples of pulsating white dwarf + pulsar binary systems. With two clocks in the system, we will be able to understand the interior structure of these helium-core white dwarfs and more accurately constrain the masses of both stars in the system, including the neutron star companions.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2013B-0004

noaoprop-help@noao.edu

Small NOAO Logo