NOAO >   Observing Info >   Approved Programs >   2014A-0141

Small NOAO Logo

Proposal Information for 2014A-0141


PI: Mike Reed, Missouri State University, mikereed@missouristate.edu
Address: Physics Department, 911 S. National, Springfield, MO 65897, USA

CoI: C. Simon Jeffery, Armagh Observatory
CoI: John Telting, Nordic Optical Telescope
CoI: Breanna Quick, Missouri State University

Title: Constraining structural models of stellar helium cores using the pulsations of Feige 48

Abstract: Asteroseismology is the art of using stellar pulsations to discern a star's detailed structure and evolutionary history. When many stars of similar structure and/or evolution can be studied, the results can be extremely powerful; examples of which include white dwarf and red giant seismology. However, the key to these successes are twofold: Observed pulsation frequencies must first be identified with spherical harmonics (modes) and mature models must exist for comparison. For subdwarf B (sdB) stars, Kepler observations have allowed progress with the former, but have indicated weaknesses in the latter. We propose using time- resolved spectroscopy combined with multicolor photometry to identify pulsation modes and constrain structure models. We propose to re-observe Feige 48 (KY UMa). We were allocated time during 2010A, but inclement weather prevented fully exploiting the pulsations. Yet those data provided surprising clues. Feige 48's an important sdB in a short-period binary, with constrained inclination and some constraints on three pulsation modes. Our proposed observations will constrain both the star and the binary system and provide calibration for models. This provides an arsenal of seismic tools for testing structure and evolution models of Feige 48 and other, previously observed, sdB stars.


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 >   2014A-0141

noaoprop-help@noao.edu

Small NOAO Logo