Revised Pulsar Spindown
Abstract
We address the issue of electromagnetic pulsar spindown by combining our experience from the two limiting idealized cases which have been studied in great extent in the past: that of an aligned rotator where ideal MHD conditions apply, and that of a misaligned rotator in vacuum. We construct a spindown formula that takes into account the misalignment of the magnetic and rotation axes, and the magnetospheric particle acceleration gaps. We show that near the death line aligned rotators spin down much slower than orthogonal ones. In order to test this approach, we use a simple Monte Carlo method to simulate the evolution of pulsars and find a good fit to the observed pulsar distribution in the P{dot P} diagram without invoking magnetic field decay. Our model may also account for individual pulsars spinning down with braking index n < 3, by allowing the corotating part of the magnetosphere to end inside the light cylinder. We discuss the role of magnetic reconnection in determining the pulsar braking index. We show, however, that n {approx} 3 remains a good approximation for the pulsar population as a whole. Moreover, we predict that pulsars near the death line have braking index values n >more »
 Authors:
 Publication Date:
 Research Org.:
 Stanford Linear Accelerator Center (SLAC)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 877495
 Report Number(s):
 SLACPUB11551
Journal ID: ISSN 0004637X; ASJOAB; astroph/0512002; TRN: US200608%%182
 DOE Contract Number:
 AC0276SF00515
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCELERATION; ALIGNMENT; DECAY; DISTRIBUTION; INCLINATION; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MONTE CARLO METHOD; PULSARS; ROTATION; SPIN; Astrophysics,ASTRO
Citation Formats
Contopoulos, Ioannis, /Athens Academy, Spitkovsky, Anatoly, and /KIPAC, Menlo Park. Revised Pulsar Spindown. United States: N. p., 2005.
Web.
Contopoulos, Ioannis, /Athens Academy, Spitkovsky, Anatoly, & /KIPAC, Menlo Park. Revised Pulsar Spindown. United States.
Contopoulos, Ioannis, /Athens Academy, Spitkovsky, Anatoly, and /KIPAC, Menlo Park. Wed .
"Revised Pulsar Spindown". United States.
doi:. https://www.osti.gov/servlets/purl/877495.
@article{osti_877495,
title = {Revised Pulsar Spindown},
author = {Contopoulos, Ioannis and /Athens Academy and Spitkovsky, Anatoly and /KIPAC, Menlo Park},
abstractNote = {We address the issue of electromagnetic pulsar spindown by combining our experience from the two limiting idealized cases which have been studied in great extent in the past: that of an aligned rotator where ideal MHD conditions apply, and that of a misaligned rotator in vacuum. We construct a spindown formula that takes into account the misalignment of the magnetic and rotation axes, and the magnetospheric particle acceleration gaps. We show that near the death line aligned rotators spin down much slower than orthogonal ones. In order to test this approach, we use a simple Monte Carlo method to simulate the evolution of pulsars and find a good fit to the observed pulsar distribution in the P{dot P} diagram without invoking magnetic field decay. Our model may also account for individual pulsars spinning down with braking index n < 3, by allowing the corotating part of the magnetosphere to end inside the light cylinder. We discuss the role of magnetic reconnection in determining the pulsar braking index. We show, however, that n {approx} 3 remains a good approximation for the pulsar population as a whole. Moreover, we predict that pulsars near the death line have braking index values n > 3, and that the older pulsar population has preferentially smaller magnetic inclination angles. We discuss possible signatures of such alignment in the existing pulsar data.},
doi = {},
journal = {Astrophysical Journal},
number = ,
volume = ,
place = {United States},
year = {Wed Dec 14 00:00:00 EST 2005},
month = {Wed Dec 14 00:00:00 EST 2005}
}

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