Thermal and non-thermal X-ray emission from the rotation-powered radio/$\gamma$-ray pulsar PSR J1740+1000

Abstract

We report the results of new XMM-Newton observations of the middle-aged ($\sim$10${}^5$ yr) radio pulsar PSR J1740+1000 carried out in 2017-2018. These long pointings ($\sim$530 ks) show that the non-thermal emission, well described by a power-law spectrum with photon index $\Gamma =1.80\pm 0.17$, is pulsed with a $\sim$30% pulsed fraction above 2 keV. The thermal emission can be well fit with the sum of two blackbodies of temperatures $k{T}_1=70\pm 4$ eV, $k{T}_2=137\pm 7$ eV, $R_1=5.4_{-0.9}^{+1.3}$ km and $R_2=0.70_{-0.13}^{+0.15}$ km (for a distance of 1.2 kpc). We found no evidence for absorption lines as those observed in the shorter XMM-Newton observations ($\sim$67 ks) of this pulsar carried out in 2006. The X-ray thermal and non-thermal components peak in anti-phase and none of them is seen to coincide in phase with the radio pulse. This, coupled with the small difference in the emission radii of the two thermal components, disfavors an interpretation in which the dipolar polar cap is heated by magnetospheric backward-accelerated particles. Comparison with the other thermally-emitting isolated neutron stars with spectra well described by the sum of two components shows that the ratios $T_2$/$T_1$ and $R_2$/$R_1$ are similar for objects of different classes. The observed values cannot be reproduced with simple temperature distributions, such as those caused by a dipolar field, indicating the presence of more complicated thermal maps.

Accepted for publication in MNRAS, 9 pages, 7 figures, 3 tables

References in corpus (21)

• HI4PI: A full-sky HI survey based on EBHIS and GASS
• A New Electron Density Model for Estimation of Pulsar and FRB Distances
• Magnetic, thermal and rotational evolution of isolated neutron stars
• Central Compact Objects in Supernova Remnants
• Model X-ray Spectra of Magnetic Neutron Stars with Hydrogen Atmospheres
• Magnetic, thermal and rotational evolution of isolated neutron stars
• X-ray Observations of Parsec-Scale Tails behind Two Middle-Aged Pulsars
• A dedicated Chandra ACIS observation of the central compact object in the Cassiopeia A supernova remnant
• 3D modelling of magneto-thermal evolution of neutron stars: method and test cases
• Sleeping beasts: strong toroidal magnetic field in quiescent magnetars explains their large pulsed fraction
• Phase resolved spectroscopy of the Vela pulsar with XMM-Newton
• A broadband X-ray study of the Geminga pulsar with NuSTAR and XMM-Newton
• A self-consistent model of isolated neutron stars: the case of the X-ray pulsar RX J0720.4-3125
• Spectral features in isolated neutron stars induced by inhomogeneous surface temperatures
• X-ray Emission from Isolated Neutron Stars revisited: 3D magnetothermal simulations
• Evaluating the Evidence of Multipolar Surface Magnetic Field in PSR J0108$-$1431
• Synchro-curvature modelling of the multi-frequency non-thermal emission of pulsars
• NICER study of pulsed thermal X-rays from Calvera: a neutron star born in the Galactic halo?
• XMM-Newton observations of PSR J0726-2612, a radio-loud XDINS
• A Search for TeV Gamma-ray Emission from Pulsar Tails by VERITAS
• Two-blackbody portraits of radiation from magnetized neutron stars

Cited by in corpus (10)

• Two decades of X-ray observations of the isolated neutron star RX J1856.5-3754: detection of thermal and non-thermal hard X-rays and refined spin-down measurement
• XMM-Newton and SRG/eROSITA observations of the isolated neutron star candidate 4XMM J022141.5-735632
• Observational connection of non-thermal X-ray emission from pulsars with their timing properties and thermal emission
• X-ray and near-infrared observations of the middle-aged pulsar B1055-52, its multiwavelength spectrum, and proper motion
• The middle-aged pulsar PSR J1741-2054 and its bow-shock nebula in far ultraviolet
• X-ray nondetection of PSR J0250+5854
• Antenna source of radio-frequency emission in ion-proton pulsars
• 4XMM J175136.8-275858: A New Magnetar Candidate?
• Investigating the mysterious nature of 1LHAASO J1740+0948u through deep XMM-Newton observations
• XMM-Newton and Chandra observations of the candidate Fermi-LAT pulsar 4FGL J1015.5-6030