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Title: OBLIQUELY ROTATING PULSARS: SCREENING OF THE INDUCTIVE ELECTRIC FIELD

Abstract

Pulsar electrodynamics has been built up by taking ingredients from two models, the vacuum-dipole model, which ignores the magnetosphere but includes the inductive electric field due to the obliquely rotating magnetic dipole, and the corotating-magnetosphere model, which neglects the vacuum inductive electric field and assumes a corotating magnetosphere. We argue that the inductive field can be neglected only if it is screened by a current, J{sub sc}, which we calculate for a rigidly rotating magnetosphere. Screening of the parallel component of the inductive field can be effective, but the perpendicular component cannot be screened in a pulsar magnetosphere. The incompletely screened inductive electric field has not been included in any model for a pulsar magnetosphere, and taking it into account has important implications. One effect is that it implies that the magnetosphere cannot be corotating, and we suggest that drift relative to corotation offers a natural explanation for the drifting of subpulses. A second effect is that this screening of the parallel inductive electric field must break down in the outer magnetosphere, and this offers a natural explanation for the acceleration of the electrons that produce pulsed gamma-ray emission.

Authors:
;  [1]
  1. SIfA, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia)
Publication Date:
OSTI Identifier:
22011873
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 745; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ELECTRIC FIELDS; GAMMA RADIATION; MAGNETIC DIPOLES; MAGNETIC FIELDS; PULSARS

Citation Formats

Melrose, D. B., and Yuen Rai. OBLIQUELY ROTATING PULSARS: SCREENING OF THE INDUCTIVE ELECTRIC FIELD. United States: N. p., 2012. Web. doi:10.1088/0004-637X/745/2/169.
Melrose, D. B., & Yuen Rai. OBLIQUELY ROTATING PULSARS: SCREENING OF THE INDUCTIVE ELECTRIC FIELD. United States. doi:10.1088/0004-637X/745/2/169.
Melrose, D. B., and Yuen Rai. 2012. "OBLIQUELY ROTATING PULSARS: SCREENING OF THE INDUCTIVE ELECTRIC FIELD". United States. doi:10.1088/0004-637X/745/2/169.
@article{osti_22011873,
title = {OBLIQUELY ROTATING PULSARS: SCREENING OF THE INDUCTIVE ELECTRIC FIELD},
author = {Melrose, D. B. and Yuen Rai},
abstractNote = {Pulsar electrodynamics has been built up by taking ingredients from two models, the vacuum-dipole model, which ignores the magnetosphere but includes the inductive electric field due to the obliquely rotating magnetic dipole, and the corotating-magnetosphere model, which neglects the vacuum inductive electric field and assumes a corotating magnetosphere. We argue that the inductive field can be neglected only if it is screened by a current, J{sub sc}, which we calculate for a rigidly rotating magnetosphere. Screening of the parallel component of the inductive field can be effective, but the perpendicular component cannot be screened in a pulsar magnetosphere. The incompletely screened inductive electric field has not been included in any model for a pulsar magnetosphere, and taking it into account has important implications. One effect is that it implies that the magnetosphere cannot be corotating, and we suggest that drift relative to corotation offers a natural explanation for the drifting of subpulses. A second effect is that this screening of the parallel inductive electric field must break down in the outer magnetosphere, and this offers a natural explanation for the acceleration of the electrons that produce pulsed gamma-ray emission.},
doi = {10.1088/0004-637X/745/2/169},
journal = {Astrophysical Journal},
number = 2,
volume = 745,
place = {United States},
year = 2012,
month = 2
}
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