Wave propagation and pair formation in pulsar magnetospheres

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:6292878

Barnard, J J

Propagation of electromagnetic waves through a relativistically outflowing electron-positron plasma were studied, and requirements for the formation of such a plasma in pulsar magnetospheres were determined. Chapter I briefly reviews the current ideas about the electrodynamics of plasmas in polar-cap models of pulsars and the emission and transfer of radiation through these plasmas. Chapter II investigates the refraction of electromagnetic waves through pulsar magnetospheres. The dispersion relation for propagation in an equal density electron-positron plasma is derived in the approximation that the magnetic field is infinite, for both cold and hot distribution functions. Equations are derived for the propagation of rays through a plasma that is inhomogeneous in density, magnetic field direction, and Lorentz factor. In chapter III the author calculates the energy transfer rate of Alfven waves into fast-mode waves from two different mechanisms: linear gradient coupling and nonlinear wave-wave coupling. In chapter IV, he calculates the minimum requirements for pair creation in a pulsar magnetic field with dipolar and quadrupolar components. Chapter V shows that cosmic rays do not enter most pulsars' magnetospheres and thus do not trigger electron-positron cascades.

• Research Organization: California Univ., Berkeley (USA)
• OSTI ID: 6292878
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics & Cosmology-- Quasi-Stellar
Radio
& X-Ray Sources-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALFVEN WAVES
ATMOSPHERES
COSMIC RADIO SOURCES
ENERGY TRANSFER
HYDROMAGNETIC WAVES
INTERACTIONS
PAIR PRODUCTION
PLASMA
PULSARS
RADIATION TRANSPORT
STELLAR ATMOSPHERES
STELLAR MAGNETOSPHERES
WAVE PROPAGATION