Interstellar grains and current flow in pulsar magnetospheres

Abstract

view Abstract Citations (14) References (33) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Interstellar grains and current flow in pulsar magnetospheres Cheng, A. F. Abstract Consequences of interstellar grain entry into radio pulsar magnetospheres are investigated. Ablation and ionization of grain matter within the light cylinder injects charges of both signs throughout the magnetosphere. Electron-positron pair creation cascades result for typical pulsar parameters. A quasi-steady current flow is maintained by these processes, which may yield a solution to the long-standing current closure problem in pulsar magnetospheres. The resulting pulsar model may provide an explanation for the striking observation that pulsar spindown rates are correlated with proper velocities. The observed correlation of the square root of the product of the period and the change in period with the pulsar proper motion is interpreted as a correlation between current flow and velocity arising from a dependence of current flow on the rate of interstellar grain destruction in the magnetosphere. In this model, grain destruction occurs within the light cylinder if the average neutron star temperature is near 10 to the 5th K. Furthermore, the true pulsar magnetic field exceeds the value conventionally inferred from the square root of the product of the period and the change in period if the current is less than the Goldreich-Julian (1969) value. In general, however, the model retains many of the phenomenological successes of earlier polar cap models. Publication: The Astrophysical Journal Pub Date: December 1985 DOI: 10.1086/163758 Bibcode: 1985ApJ...299..917C Keywords: Bow Waves; Interstellar Matter; Pulsar Magnetospheres; Pulsars; Radio Stars; Current Density; Electron-Positron Pairs; Neutron Stars; Photoelectric Emission; Shock Waves; Stellar Temperature; Thermal Radiation; Astrophysics full text sources ADS |