X-ray pulsar radiation from polar cap heated by back-flow bombardment

Abstract

We consider the problem of the thermal X-ray radiation from the hot polar cap of radio pulsars showing evidence of \EB subpulse drift in radio band. In our recent Paper I, using the partially screened gap (PSG) model of inner acceleration region we derived a simple relationship between the drift rate of subpulses observed in a radio-band and the thermal X-ray luminosity from polar caps heated by the back-flow particle bombardment. This relationship can be tested for pulsars in which the so-called carousel rotation time $P_4$, reflecting the \EB plasma drift, and the thermal X-ray luminosity $L_x$ from the hot polar cap are known. To test the model we used only two available pulsars: PSRs B0943+10 and B1133+16. They both satisfied the model prediction, although due to low photon statistics the thermal component could not be firmly identified from the X-ray data. Nevertheless, these pulsars were at least consistent with PSG pulsar model. In the present paper we consider two more pulsars: PSRs B0656+14 and B0628-28, whose data have recently become available. In PSR B0656+14 the thermal radiation from the hot polar cap was clearly detected, and PSR B0628-28 also seems to have such a component. In all cases for which both $P_4$ and $L_x$ are presently known, the PSG pulsar model seems to be fully confirmed. Other available models of inner acceleration region fail to explain the observed relationship between radio and X-ray data. The pure vacuum gap model predicts too high $L_x$ and too low $P_4$, while the space charge limited model predicts too low $L_x$ and the origin of the subpulse drift has no natural explanation.

References in corpus (26)

• Matter in Strong Magnetic Fields
• Re-examining the X-Ray versus Spin-Down Luminosity Correlation of Rotation Powered Pulsars
• The subpulse modulation properties of pulsars at 21 cm
• Pulsar Polar Cap Heating and Surface Thermal X-Ray Emission II. Inverse Compton Radiation Pair Fronts
• Drifting subpulses and inner acceleration regions in radio pulsars
• Radio Pulsar Death Line Revisited: Is PSR J2144-3933 Anomalous?
• Pulsar Magnetospheric Emission Mapping: Images and Implications of Polar-Cap Weather
• Full polar cap cascade scenario: $\gamma$-ray and X-ray luminosities from spin-powered pulsars
• Spark Model for Pulsar Radiation Modulation Patterns
• On the polar caps of the 3 Musketeers
• Drifting Sub-Pulse Analysis Using the Two-Dimensional Fourier Transform
• The distance and radius of the neutron star PSR B0656+14
• Density-Functional-Theory Calculations of Matter in Strong Magnetic Fields: II. Infinite Chains and Condensed Matter
• Pulse-to-pulse intensity modulation and drifting subpulses in recycled pulsars
• Unraveling the drift behaviour of the remarkable pulsar PSR B0826-34
• The bright spiky emission of pulsar B0656+14
• XMM-Newton observation of the drifting pulsar B0943+10
• X-ray Emission from the nearby PSR B1133+16
• On the formation of inner vacuum gaps in radio pulsars
• The Topology and Polarisation of Subbeams Associated with the `Drifting' Subpulse Emission of Pulsar B0943+10 -- IV. Q-to-B-Mode Recovery Dynamics
• Formation of a Partially-Screened Inner Acceleration Region in Radio Pulsars: Drifting Subpulses and Thermal X-Ray Emission from Polar Cap Surface
• A multiwavlength study of PSR B0628-28: The first overluminous rotation-powered pulsar?
• Topology and Polarisation of Subbeams Associated With Pulsar B0943+10's `Drifting'-Subpulse Emission: II. Analysis of Gauribidanur 35-MHz Observations
• Fluctuation Properties and Polar Emission Mapping of Pulsar B0834+06 at Decameter Wavelengths
• Chandra and XMM-Newton observations of the exceptional pulsar PSR B0628-28
• Interrelation between radio and X-ray signatures of drifting subpulses in pulsars

Cited by in corpus (11)

• The spectrum of the recycled PSR J0437-4715 and its white dwarf companion
• Two Modes of Partially Screened Gap
• Creation of magnetic spots at the neutron star surface
• XMM-Newton Observations of Radio Pulsars B0834+06 and B0826-34 and Implications for Pulsar Inner Accelerator
• Radio pulsar activity and the crustal Hall drift
• A new X-ray look into four old pulsars
• Instabilities nulls and sub-pulse drift in radio pulsars
• Explaining the subpulse drift velocity of pulsar magnetosphere within the space-charge limited flow model
• Single pulse analysis of PSR B1133+16 at 8.35 GHz and carousel circulation time
• The radio and X-ray mode-switching pulsar PSR B0943+10
• X-rays from the mode-switching PSR B0943+10