Explaining the subpulse drift velocity of pulsar magnetosphere within the space-charge limited flow model

Abstract

We try to explain the subpulse drift phenomena adopting the space-charge limited flow (SCLF) model and comparing the plasma drift velocity in the inner region of pulsar magnetospheres with the observed velocity of drifting subpulses. We apply the approach described in a recent paper of van Leeuwen & Timokhin (2012), where it was shown that the standard estimation of the subpulse drift velocity through the total value of the scalar potential drop in the inner gap gives inaccurate results, while the exact expression relating the drift velocity to the gradient of the scalar potential should be used instead. After considering a selected sample of sources taken from the catalog of Weltevrede, Edwards & Stappers (2006) with coherently drifting subpulses and reasonably known observing geometry, we show that their subpulse drift velocities would correspond to the drift of the plasma located very close or above the pair formation front. Moreover, a detailed analysis of PSR B0826-34 and PSR B0818-41 reveals that the variation of the subpulse separation with the pulse longitude can be successfully explained by the dependence of the plasma drift velocity on the angular coordinates.

14 pages, 6 figures, 2 tables

References in corpus (11)

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• The subpulse modulation properties of pulsars at 92 cm and the frequency dependence of subpulse modulation
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• XMM-Newton observation of the drifting pulsar B0943+10
• Detection of X-ray Emission from the Very Old Pulsar J0108-1431
• Radio pulsar activity and the crustal Hall drift
• PSR B0826-34: Sometimes a rotating radio transient
• Discovery of a remarkable subpulse drift pattern in PSR B0818-41
• A Quantitative Non-radial Oscillation Model for the Subpulses in PSR B0943+10
• X-ray pulsar radiation from polar cap heated by back-flow bombardment
• Results from multi-frequency observations of PSR B0826-34

Cited by in corpus (6)

• Theory of pulsar magnetosphere and wind
• Electromagnetic fields of slowly rotating magnetized compact stars in conformal gravity
• General-relativistic pulsar magnetospheric emission
• Electromagnetic fields in the exterior of an oscillating relativistic star -- II. Electromagnetic damping
• Variations of $P_2$ in subpulse drifting pulsars
• Testing the circularity of PSR B0818-41's carousel