主要内容:
精彩摘抄:
文章信息:
- · arXiv e-print (arXiv:1004.3378)
- · References in the Article
- · Also-Read Articles (Reads History)
- ·
- · Translate This Page
| Title: |
| Quark-Novae in post-accretion Low-Mass X-ray Binaries: A universal model for short-hard Gamma-Ray Bursts |
| Authors: |
| Ouyed, Rachid; Staff, Jan E.; Jaikumar, Prashanth |
| Publication: |
| eprint arXiv:1004.3378 |
| Publication Date: |
| 04/2010 |
| Origin: |
| ARXIV |
| Keywords: |
| Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology |
| Comment: |
| 11 journal pages, 3 figures and 1 Table -- Submitted to ApJ. |
| Bibliographic Code: |
| 2010arXiv1004.3378O |
Abstract
We show that several features reminiscent of short-hard GRBs arise naturally when Quark-Novae occur in post-accretion low-mass X-ray binaries with a circumbinary disk. Post-accretion conditions in a neutron star-white dwarf binary are just right for the conversion of the neutron star to a quark star (Quark-Nova). In our model, the subsequent interaction of material from the neutron star's ejected crust with the circumbinary disk explains the duration, variability and near-universal nature of the prompt emission in short-hard GRBs. We also describe a statistical approach to ejecta break-up and collision to obtain the photon spectrum in our model, which turns out remarkably similar to the empirical Band function (Band et al. 1993). We apply the model to the fluence and spectrum of GRB 000727, GRB 000218, and GRB980706A obtaining excellent fits. Extended emission (spectrum and duration) is explained by shock-heating and ablation of the white dwarf by the highly energetic ejecta. Depending on the orbital separation when the Quark-Nova occurs, we isolate interesting regimes within our model when both prompt and extended emission can occur. We find that the spectrum can carry signatures typical of Type Ib/c SNe, thus providing an alternative to the collapsar scenario. Late X-ray activity is due to accretion onto the quark star as well as its spin-down luminosity, while afterglows arise from the expanding shell of material from the shock-heated expanding circumbinary disk. We find a correlation between the duration and spectrum of short-hard GRBs as well as modest hard-to-soft time evolution of the peak energy.
没有评论:
发表评论