Violent stellar merger model for transient events
| Autor: | Noam Soker, R. Tylenda |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Physics
Shock wave Stellar mass Astrophysics::High Energy Astrophysical Phenomena Astrophysics (astro-ph) Relative velocity FOS: Physical sciences Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics Mass ratio Space and Planetary Science Orbital motion Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics Binary system Low Mass Astrophysics::Galaxy Astrophysics Main sequence |
| Zdroj: | Monthly Notices of the Royal Astronomical Society. 373:733-738 |
| ISSN: | 1365-2966 0035-8711 |
| DOI: | 10.1111/j.1365-2966.2006.11056.x |
| Popis: | We derive the constraints on the mass ratio for a binary system to merge in a violent process. We find that the secondary to primary stellar mass ratio should be ~0.003 < (M_2/M_1) < ~0.15. A more massive secondary star will keep the primary stellar envelope in synchronized rotation with the orbital motion until merger occurs. This implies a very small relative velocity between the secondary star and the primary stellar envelope at the moment of merger, and therefore very weak shock waves, and low flash luminosity. A too low mass secondary will release small amount of energy, and will expel small amount of mass, which is unable to form an inflated envelope. It can however produce a quite luminous but short flash when colliding with a low mass main sequence star. Violent and luminous mergers, which we term mergebursts, can be observed as V838 Monocerotis type events, where a star undergoes a fast brightening lasting days to months, with a peak luminosity of up to ~10^6 Lo followed by a slow decline at very low effective temperatures. Accepted by MNRAS |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text