SIMBAD references

A rapidly spinning, strongly magnetized neutron star (NS) is invoked as the central engine for some gamma-ray bursts (GRBs), especially, the 'internal plateau' feature of X-ray afterglow. However, for these 'internal plateau' GRBs, how to produce their prompt emission remains an open question. Two different physical processes have been proposed in the literature, (1) a new-born NS is surrounded by a hyper-accreting and neutrino cooling disc, the GRB jet can be powered by neutrino annihilation aligning the spin axis; (2) a differentially rotating millisecond pulsar was formed due to different angular velocity between the interior core and outer shell parts of the NS, which can power an episodic GRB jet. In this paper, by analysing the data of one peculiar GRB 070110 (with internal plateau), we try to test which model is being favoured. By deriving the physical parameters of magnetar with observational data, the parameter regime for initial period (P₀) and surface polar cap magnetic field (B_p) of the central NS are 0.96 ∼ 1.2 ms and (2.4 ∼ 3.7) x 10¹⁴ G, respectively. The radiative efficiency of prompt emission is about η_γ ∼ 6 per cent. However, the radiative efficiency of internal plateau (η_X) is larger than 31 per cent assuming the M_NS ∼ 1.4 M_☉ and P_{0
rm }
sim 1.2
rm
,ms. The clear difference between the radiation efficiencies of prompt emission and internal plateau implies that they maybe originated from different components (e.g. prompt emission from the relativistic jet powered by neutrino annihilation, while the internal plateau from the magnetic outflow wind).