NOAO >   Observing Info >   Approved Programs >   2017B-0173

Small NOAO Logo

Program Information for 2017B-0173


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

CoI: Warren Brown, Harvard-Smithsonian Center for Astrophysics
CoI: Alek Kosakowski, U. of Oklahoma

Title: The ELM Survey South

Abstract: The ELM Survey, a radial velocity survey of photometrically identified extremely low-mass (ELM) white dwarf candidates, has been the most successful survey for finding merging double white dwarf systems. This survey has discovered more than 40 merging systems, including seven sub-hour orbital period, three eclipsing, and two gravitational wave verification binaries. Here we propose to extend the ELM Survey to the southern hemisphere through $ugriz$ photometry of 3700 square degrees from the ESO Public Survey ATLAS Data Release 3. Our pilot survey at the SOAR telescope in March 2017 demonstrates that our color selection works well, with a 10% success rate in finding ELMs. We identify 203 fall-sky targets brighter than g=18.5 mag with colors consistent with ELM white dwarfs. Here we request 5 nights of SOAR 4m + Goodman spectrograph to follow-up these 203 targets. Along with our proposed 6.5m Magellan observations (through CfA), our goal is to observe all of the photometrically selected ELM white dwarf candidates in ATLAS DR3, and constrain their orbital periods. ELM color selection is a refined version of the original ELM Survey and Hypervelocity Star Survey color selections. Hence, our survey will find both short period binaries as well as the Hypervelocity stars in the south. Given the success of the ELM Survey and the Hypervelocity star survey, our proposed survey is guaranteed to produce exciting results, including sub-hour orbital period and eclipsing detached binary white dwarfs, and hypervelocity stars. The former will provide stringent constraints on the double white dwarf merger rate and their contribution to supernovae Ia, R Cor Bor, and AM CVn stars.

Program Type: Standard/Galactic

Scheduled Nights:
Run 1 (2017B):  SOAR/Goodman -- 5n on Sep 22 - Sep 26 2017


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 >   2017B-0173

noaoprop-help@noao.edu

Small NOAO Logo