Reactivation of the High Magnetic Field Pulsar PSR J1846-0258 with Magnetar-like Bursts

摘要

We report on the 2020 reactivation of the energetic high magnetic field pulsar PSR J1846-0258 and its pulsar wind nebula (PWN) after 14 yr of quiescence with new Chandra and Green Bank Telescope observations. The emission of short-duration bursts from J1846-0258 was accompanied by an enhancement of X-ray persistent flux and significant spectral softening, similar to those observed during its first bursting episode in 2006. The 2020 pulsar spectrum is described by a power-law model with a photon index Gamma = 1.7 0.3 in comparison to a Gamma = 1.2 0.1 before outburst, and shows evidence of an emerging thermal component with blackbody temperature kT = 0.7 0.1 keV. The 0.5-10 keV unabsorbed flux increased from 5.4(-0.5)(+0.4) x 10(-12) erg cm(-2) s(-1) in quiescence to 1.3(-0.2)(+0.3) x 10(-11) erg cm(-2) s(-1) following the outburst. We did not detect any radio pulsations from the pulsar at 2 GHz, and we place an upper limit of 7.1 mu Jy and 55 mJy for the coherent pulsed emission and single pulses, respectively. The 2020 PWN spectrum, characterized by a photon index of 1.92 0.04 and X-ray luminosity of (1.2 0.1) x 10(35) erg s(-1) at a distance of 5.8 kpc, is consistent with those observed before the outburst. An analysis of regions closer to the pulsar shows small-scale time variabilities and brightness changes over the 20 yr period from 2000 to 2020, while the photon indices did not change. We conclude that the outburst in PSR J1846-0258 is a combination of crustal and magnetospheric effects, with no significant burst-induced variability in its PWN based on the current observations.