English

X-ray light curve in GRB 170714A: evidence for quark star?

High Energy Astrophysical Phenomena 2018-02-28 v3

Abstract

Two plateaus and one following bump in the X-ray light curve of GRB 170714A have been detected by the \textit{Swift}/X-Ray Telescope, which could be very meaningful for the central engine of gamma-ray bursts (GRBs), implying that the origin of this burst might be different from that of other ultra-long GRBs. We propose that merging two neutron stars into a hyper-massive quark star (QS) and then collapsing into a black hole (BH), with a delay time around 10410^4~s, could be responsible for those X-ray components. The hyper-massive QS is initially in a fluid state, being turbulent and differentially rotating, but would be solidified and release its latent heat injected into the GRB fireball (lasting about 10310^3~s during the liquid-solid phase transition). Magnetic field as high as 1015\sim 10^{15}~G could be created by dynamo action of the newborn liquid QS, and a magnetar-like central engine (after solidification) supplies significant energy for the second plateau. More energy could be released during a fall-back accretion after the post-merger QS collapses to a BH, and the X-ray bump forms. This post-merger QS model might be tested by future observations, with either advanced gravitational wave detectors (e.g., advanced LIGO and VIRGO) or X-ray/optical telescopes.

Keywords

Cite

@article{arxiv.1710.04355,
  title  = {X-ray light curve in GRB 170714A: evidence for quark star?},
  author = {Shu-Jin Hou and Tong Liu and Ren-Xin Xu and Hui-Jun Mu and Cui-Ying Song and Da-Bin Lin and Wei-Min Gu},
  journal= {arXiv preprint arXiv:1710.04355},
  year   = {2018}
}

Comments

6 pages, 1 figure, 1 table, accepted for publication in ApJ