Bunching mechanism for coherent curvature radiation in pulsar magnetospheres

Journal Article · Tue Mar 15 04:00:00 EST 1977 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/155105· OSTI ID:7118274

Cheng, A F; Ruderman, M A

A relativistic plasma consisting of electron-positron pairs produced by photons initially has identical charge and current distributions in its two components. We show that when such a plasma moves along a curved field line of a rotating pulsar magnetosphere, a net charge density and a relative streaming between the electrons and the positrons must develop. The resulting two-stream instability bunches charges on a time scale ..gamma../sub plus-or-minus/ /sup 2/..omega../sup -1/ with ..gamma../sub plus-or-minus/ the average laboratory Lorentz factor and ..omega.. the laboratory plasma mode frequency. For an electron-positron plasma produced in a pulsar magnetosphere, the resulting charge bunching causes curvature radiation to be coherent in the microwave region. The growth rate of the instability approx.10/sup 3/-10/sup 4/ s/sup -1/ suffices to yield a large wave amplitude within the light cylinder. The results are generalized to oblique rotator geometries. For the unstable modes considered, inclusion of interaction with the radiation field can lead to amplication of bunching.

• Research Organization: Columbia University
• OSTI ID: 7118274
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 212:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
ATMOSPHERES
CHARGE DISTRIBUTION
COSMIC RADIO SOURCES
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
FLUID MECHANICS
HYDRODYNAMICS
LEPTONS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MATHEMATICAL MODELS
MECHANICS
PLASMA
POSITRONS
PULSARS
STAR MODELS
STELLAR ATMOSPHERES
STELLAR MAGNETOSPHERES