A large TESS sample of short-period ellipsoidal binary candidates

Binaries with small orbital separations display photometric signatures that result

from the tidal distortion of their component stars, as well as from Doppler

beaming and from reflection. These signatures can be used to identify non-eclipsing

binary systems, producing a sample whose selection effects differ from those of

any eclipsing binary catalogue.

We used the BEER algorithm (Faigler et al. 2011, 2013, 2015a, 2015b), which

fits for all three of these effects, to search through the light-curves of 9,000,000 targets

derived from the TESS full-frame images, and selected 50,000 candidate

binaries with orbital periods < 7 days. We will present an overview of this sample,

including its selection effects and contaminants, and we will show how the sample can be

used to illuminate the underlying population of short-period binaries, in particular the

distributions of periods and masses.

In addition, hidden among the sample are likely to be a number of binaries with

non-accreting neutron star or black hole companions. We will demonstrate how

we have selected promising candidates for such compact binaries, and present

our preliminary attempts to follow up on these candidates.