The Rømer Delay and Mass Ratio of the sdB+dM Binary 2M 1938+4603 from Kepler Eclipse Timings

Details The Rømer Delay and Mass Ratio of the sdB+dM Binary 2M 1938+4603 from Kepler Eclipse Timings The Rømer Delay and Mass Ratio of the sdB+dM Binary 2M 1938+4603 from Kepler Eclipse Timings

2012-04-15

arxiv.org/abs/1204.3321v1

Astronomy and Astrophysics

Astrophysics

Solar and Stellar Astrophysics

Accepted for publication in The Astrophysical Journal. 7 pages, 6 figures, 3 tables (2 online only)

Scientific paper

The eclipsing binary system 2M 1938+4603 consists of a pulsating hot subdwarf B star and a cool M dwarf companion in an effectively circular three-hour orbit. The light curve shows both primary and secondary eclipses, along with a strong reflection effect from the cool companion. Here we present constraints on the component masses and eccentricity derived from the R{\o}mer delay of the secondary eclipse. Using six months of publicly-available Kepler photometry obtained in Short Cadence mode, we fit model profiles to the primary and secondary eclipses to measure their centroid values. We find that the secondary eclipse arrives on average 2.06 +/- 0.12 s after the midpoint between primary eclipses. Under the assumption of a circular orbit, we calculate from this time delay a mass ratio of q = 0.2691 +/- 0.0018 and individual masses of M_sd = 0.372 +/- 0.024 Msun and M_c = 0.1002 +/- 0.0065 Msun for the sdB and M dwarf, respectively. These results differ slightly from those of a previously-published light curve modeling solution; this difference, however, may be reconciled with a very small eccentricity, e cos \omega\ ~ 0.00004. We also report an orbital period decrease of P-dot = (-1.23 +/- 0.07) x 10^-10.

Affiliated with

Also associated with

No associations

Rating

The Rømer Delay and Mass Ratio of the sdB+dM Binary 2M 1938+4603 from Kepler Eclipse Timings does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Rømer Delay and Mass Ratio of the sdB+dM Binary 2M 1938+4603 from Kepler Eclipse Timings, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Rømer Delay and Mass Ratio of the sdB+dM Binary 2M 1938+4603 from Kepler Eclipse Timings will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-5727