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تسجيل مستخدم جديدReactivation of the high-magnetic field pulsar PSR J1846--0258 with magnetar-like bursts
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We report on the 2020 reactivation of the energetic high-magnetic field pulsar PSR J1846-0258 and its pulsar wind nebula (PWN) after 14 years 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 powerlaw model with a photon index Gamma=1.7pm0.3 in comparison to a Gamma=1.2pm0.1 before outburst and shows evidence of an emerging thermal component with blackbody temperature kT=0.7pm0.1 keV. The 0.5--10 keV unabsorbed flux increased from 5.4e-12 erg/cm^2/s in quiescence to 1.3e-11 erg/cm^2/s following the outburst. We did not detect any radio emission from the pulsar at 2 GHz and place an upper limit of 7.1 uJy and 55 mJy for the coherent pulsed emission and single-pulses, respectively. The 2020 PWN spectrum, characterized by a photon index of 1.92pm0.04 and X-ray luminosity of 1.2e-35 erg/s 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.
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We report the detection of the pulsed signal of the radio-quiet magnetar-like pulsar PSR J1846-0258 in the high-energy gr-ray data of the Fermi Large Area Telescope (Fermi LAT). We produced phase-coherent timing models exploiting RXTE PCA and Swift X
RT monitoring data for the post- (magnetar-like) outburst period from 2007 August 28 to 2016 September 4, with independent verification using INTEGRAL ISGRI and Fermi GBM data. Phase-folding barycentric arrival times of selected Fermi LAT events from PSR J1846-0258, resulted in a 4.2 sigma detection (30--100 MeV) of a broad pulse consistent in shape and aligned in phase with the profiles that we measured with Swift XRT (2.5--10 keV), INTEGRAL ISGRI (20--150 keV) and Fermi GBM (20--300 keV). The pulsed flux (30--100 MeV) is (3.91 +/- 0.97)E-9 photons/(cm^2 s MeV). Declining significances of the INTEGRAL ISGRI 20--150 keV pulse profiles suggest fading of the pulsed hard X-ray emission during the post-outburst epochs. We revisited with greatly improved statistics the timing and spectral characteristics of PSR B1509-58 as measured with the Fermi LAT. The broad-band pulsed emission spectra (from 2 keV up to GeV energies) of PSR J1846-0258 and PSR B1509-58 can be accurately described with similarly curved shapes, with maximum luminosities at 3.5 +/- 1.1 MeV (PSR J1846-0258) and 2.23 +/- 0.11 MeV (PSR B1509-58). We discuss possible explanations for observational differences between Fermi LAT detected pulsars that reach maximum luminosities at GeV energies, like the second magnetar-like pulsar PSR J1119-6127, and pulsars with maximum luminosities at MeV energies, which might be due to geometric differences rather than exotic physics in high-B fields.
PSR J1846-0258 is a radio-quiet rotation-powered pulsar at the center of Supernova remnant Kes 75. It is the youngest pulsar (~723 year) of all known pulsars and slows down very predictably since its discovery in 2000. Till June 7, 2006 very stable b
ehavior has been displayed both in the temporal and spectral domains with pulsed emission detectable by INTEGRAL IBIS ISGRI and RXTE HEXTE up to ~150 keV. Then, a dramatic brightening was detected of the pulsar during June 7-12, 2006 Chandra observations of Kes 75. This radiative event, lasting for ~55 days, was accompanied by a huge timing glitch, reported on for the first in present work. Moreover, several short magnetar-like bursts were discovered. In this work not only the time-averaged pre-outburst X-ray/soft gamma-ray characteristics are discussed in detail, but also the spectral evolution during the outburst and its relaxation phase are addressed using RXTE PCA and HEXTE and INTEGRAL IBIS ISGRI data.
PSR J1846-0258 is an object which straddles the boundary between magnetars and rotation powered pulsars. Though behaving for many years as a rotation-powered pulsar, in 2006, it exhibited distinctly magnetar-like behavior - emitting several short har
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We present broad-band X-ray spectroscopy of the energetic components that make up the supernova remnant (SNR) Kesteven 75 using concurrent 2017 Aug 17-20 XMM-Newton and NuSTAR observations, during which the pulsar PSR J1846-0258 is found to be in the
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