What is causing the eclipse in the millisecond binary pulsar

Journal Article · Sat Jul 01 04:00:00 EDT 1989 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/167649· OSTI ID:5557115

Rasio, F A; Shapiro, S L; Teukolsky, S A ^[1]

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1. Cornell Univ., Ithaca, NY (USA)

Possible physical mechanisms for explaining the radio eclipses in the millisecond binary pulsar PSR 1957 + 20 are discussed. If, as recent observations suggest, the duration of the eclipses depends on the observing frequency, a plausible mechanism is free-free absorption of the radio pulses by a low-density ionized wind surrounding the companion. Detailed numerical calculations are performed for this case, and it is found that all of the observations made at 430 MHz can be reliably reproduced, including the asymmetry in the excess time delay of the pulses. The model leads to definite predictions for the duration of the eclipse at other observing frequencies, as well as the radio intensity and excess time delay of the pulses as a function of orbital phase. If the duration of the eclipses were found to be independent of frequency, then the likely mechanism would be reflection of the radio signal at a contact discontinuity between a high-density wind and the pulsar radiation. In this case, however, it is difficult to explain the observed symmetry of the eclipse. 12 refs.

• OSTI ID: 5557115
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 342; ISSN ASJOA; ISSN 0004-637X
• 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
BINARY STARS
COSMIC RADIO SOURCES
ECLIPSE
MATHEMATICAL MODELS
MATHEMATICS
NUMERICAL ANALYSIS
ORBITS
PULSARS
PULSES
STAR MODELS
STARS
STELLAR ACTIVITY
STELLAR WINDS