Astronomy and Astrophysics – Astronomy
Scientific paper
Mar 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011basi...39....1v&link_type=abstract
Bulletin of the Astronomical Society of India, Vol. 39, p. 1-20 (2011)
Astronomy and Astrophysics
Astronomy
3
Stars: Binaries: General, Stars: Evolution, Stars: White Dwarfs, Stars: Neutron, Stars: Pulsars: General, Stars: Supernovae: General
Scientific paper
The Chandrasekhar limit is of key importance for the evolution of white dwarfs in binary systems and for the formation of neutron stars and black holes in binaries. Mass transfer can drive a white dwarf in a binary over the Chandrasekhar limit, which may lead to a Type Ia supernova (in case of a CO white dwarf) or an Accretion-Induced Collapse (AIC, in the case of an O-Ne-Mg white dwarf; and possibly also in some CO white dwarfs) which produces a neutron star. The direct formation of neutron stars or black holes out of degenerate stellar cores that exceed the Chandrasekhar limit, occurs in binaries with components that started out with masses ≥ 8 M_&sun;.
This paper first discusses possible models for Type Ia supernovae, and then focusses on the formation of neutron stars in binary systems, by direct core collapse and by the AIC of O-Ne-Mg white dwarfs in binaries. Observational evidence is reviewed for the existence of two different direct neutron-star formation mechanisms in binaries: (i) by electron-capture collapse of the degenerate O-Ne-Mg core in stars with initial masses in the range of 8 to about 12 M_&sun;, and (ii) by iron-core collapse in stars with inital masses above this range. Observations of neutron stars in binaries are consistent with a picture in which neutron stars produced by e-capture collapse have relatively low masses, ˜1.25 M_&sun;, and received hardly any velocity kick at birth, whereas neutron stars produced by iron-core collapses are more massive and received large velocity kicks at birth. Many of the globular cluster neutron stars and also some of the neutron stars in low-mass binaries in the Galactic disk are likely to have been produced by AIC of O-Ne-Mg white dwarfs in binaries. AIC is expected to produce normal strongly magnetized neutron stars, which in binaries can evolve into millisecond pulsars through the usual recycling scenario.
No associations
LandOfFree
Compact stars and the evolution of binary systems 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 Compact stars and the evolution of binary systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Compact stars and the evolution of binary systems will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-862062