On the orbital periods of the AM CVn stars HP Librae and V803 Centauri

Details On the orbital periods of the AM CVn stars HP Librae and V803 Centauri On the orbital periods of the AM CVn stars HP Librae and V803 Centauri

2007-05-03

arxiv.org/abs/0705.0402v1

Mon.Not.Roy.Astron.Soc.379:176-182,2007

Astronomy and Astrophysics

Astrophysics

Accepted for publication in MNRAS

Scientific paper

10.1111/j.1365-2966.2007.11931.x

We analyse high-time-resolution spectroscopy of the AM CVn stars HP Librae and V803 Centauri, taken with the New Technology Telescope (NTT) and the Very Large Telescope (VLT) of the European Southern Observatory, Chile. We present evidence that the literature value for V803 Cen's orbital period is incorrect, based on an observed `S-wave' in the binary's spectrogram. We measure a spectroscopic period P=1596.4+/-1.2s of the S-wave feature, which is significantly shorter than the 1611-second periods found in previous photometric studies. We conclude that the latter period likely represents a `superhump'. If one assumes that our S-wave period is the orbital period, V803 Cen's mass ratio can be expected to be much less extreme than previously thought, at q~0.07 rather than q~0.016. This relaxes the constraints on the masses of the components considerably: the donor star does then not need to be fully degenerate, and the mass of the accreting white dwarf no longer has to be very close to the Chandrasekhar limit. For HP Lib, we similarly measure a spectroscopic period P=1102.8+/-0.2s. This supports the identification of HP Lib's photometric periods found in the literature, and the constraints upon the masses derived from them.

Affiliated with

Also associated with

No associations

Rating

On the orbital periods of the AM CVn stars HP Librae and V803 Centauri 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 On the orbital periods of the AM CVn stars HP Librae and V803 Centauri, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the orbital periods of the AM CVn stars HP Librae and V803 Centauri will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-496809