A First Look at a Short Period, Extremely Deep-Eclipsing Polar
Abstract
We request exploratory follow-up of a new short period (95 min.), white dwarf binary, likely a polar with no accretion disk, that shows one of the deepest optical eclipses known (>5.7 mag). Such binaries are rare but valuable as the system's inclination is strongly constrained; high time-resolution spectrophotometry, especially in and out of eclipse, allows "tomography" of the accretion flow and direct measurement of the radii of the white dwarf and its companion. This system shows no J band eclipse, i.e., it must have an unusually cool, low mass secondary, an M8+ dwarf. This combined with the short period suggests we may have a magnetic "period bouncer," a late binary evolutionary stage theoretically predicted to be common but difficult to detect in practice.
- Publication:
-
XMM-Newton Proposal
- Pub Date:
- October 2010
- Bibcode:
- 2010xmm..prop..141C
- Keywords:
-
- White Dwarf Binaries;
- Neutron Star Binaries;
- Cataclysmic Variables;
- ULXs;
- Black Holes;
- LSQ 172554.8-64