Hypernovae, Black Holes, and Galactic Chemical Evolution

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We discuss the characteristics of nucleosynthesis in 'Hypernovae', i.e., supernovae with very large explosion energies (≳ 1052 ergs) both in 1D (spherical explosions) and 2D (aspherical explosions). The hypernova yields compared to those of ordinary core-collapse supernovae show the following characteristics: 1) Complete Si-burning takes place in more extended regions, so that the mass ratio between the complete and incomplete Si burning regions is generally larger in hypernovae than normal supernovae. 2) Si-burning takes place in lower density regions, so that the effects of α-rich freezeout is enhanced. Thus 44Ca, 48Ti, and 64Zn are produced more abundantly than in normal supernovae. 3) Oxygen burning also takes place in more extended regions for the larger explosion energy. Then a larger amount of Si, S, Ar, and Ca ("Si") are synthesized, which makes the "Si"/O ratio larger. Aspherical explosions lead to a strong α-rich freezeout, thus enhancing the abundance ratios [44Ca, 48Ti, and 64Zn / Fe] in the ejecta as well as the aspherical element distribution in the ejecta. We examine the nature of hypernovae by comparing the above characteristic with observations. We suggest that hypernova explosions are intrinsically aspherical events (which comes from the modeling of the late time spectra of SN1998bw), that such explosions are related with black hole formations (from the modeling of the black hole binary Nova Sco), and that hypernovae have made important contribution to the early Galactic (and Cosmic) chemical evolution.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Hypernovae, Black Holes, and Galactic Chemical Evolution 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 Hypernovae, Black Holes, and Galactic Chemical Evolution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hypernovae, Black Holes, and Galactic Chemical Evolution will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-839885

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.