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

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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 $10^4$~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 $10^3$~s during the liquid-solid phase transition).
• Magnetic field as high as $\sim 10^{15}$~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.