Choose timezone
Your profile timezone:
Journal Club
Lucky planets: how circum-binary planets survive the supernova in one of the inner-binary components
→
Europe/Rome
0/0-1 - Aula A (Dipartimento di Fisica e Astronomia - Edificio ex-Rizzato)
Description
Speakers: Anjana Mohandasan (Università degli Studi di Padova)
A planet hardly ever survives the supernova of the host star in a bound orbit, becausemass loss in the supernova and the natal kick imparted to the newly formed compactobject cause the planet to be ejected. A planet in orbit around a binary has a considerablyhigher probability to survive the supernova explosion of one of the inner binary stars. Inthose cases, the planet most likely remains bound to the companion of the exploding star,whereas the compact object is ejected. We estimate this to happen to∼1/33 the circum-binary planetary systems. These planetary orbits tend to be highly eccentric (e>∼0.9),and∼20 % of these planets have retrograde orbits compared to their former binary. Theprobability that the planet as well as the binary (now with a compact object) remainsbound is about ten times smaller (∼3·10−3). We then expect the Milky way Galaxyto host<∼10 x-ray binaries that are still orbited by a planet, and<∼150 planets thatsurvived in orbit around the compact object’s companion. These numbers should beconvolved with the fraction of massive binaries that is orbited by a planet.
