NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Propagation in a shearing plasma. II - Turbulence and the frequency range of pulsar microstructureNumerical calculations are presented which explore the propagation of radio waves and pulses through a turbulent shearing plasma. A stochastic model is used to describe the turbulent velocity field, in which random fluctuations are superposed on a mean profile. Both Gaussian wave packets and shot-noise pulses polarized in the plane of shearing acquire quasi-periodic intensity modulations above the rest-frame plasma frequency. The frequency range over which these modulations appear is shown to depend on the spatial correlation length of the turbulent fluctuations and on their standard deviation from the mean velocity. The period of the modulations is variable from one realization of the random process to the next, and the average period is frequency dependent. The results of these calculations lend further support to a model for pulsar microstructure in which periodic micropulses are pure temporal modulations of the emitted radiation due to propagation effects in magnetospheric shearing regions. It is shown that turbulence on a scale of approximately 10 cm can produce these quasi-periodic modulations over a frequency range comparable to that of observed microstructure.
Document ID
19800061042
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Harding, A. K.
(NASA Goddard Space Flight Center Laboratory for High Energy Astrophysics, Greenbelt, Md., United States)
Tademaru, E.
(Massachusetts, University Amherst, Mass., United States)
Date Acquired
August 10, 2013
Publication Date
June 15, 1980
Publication Information
Publication: Astrophysical Journal
Subject Category
Astrophysics
Accession Number
80A45212
Funding Number(s)
CONTRACT_GRANT: NSF AST-75-23581
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available