IS GEMINGA A GLITCHING PULSAR

Date

1993-06-01

Author

ALPAR, MA
OGELMAN, H
SHAHAM, J

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The recent discovery that Geminga is a pulsar has been followed by indications of an anomalous second derivative nu double overdot = 2.8(1.6) x 10(-25) Hz s-1 in the COS-B data, yielding a braking index n congruent-to 31 +/- 18. We propose that Geminga is a glitching pulsar with dynamical parameters similar to those of the Vela pulsar, whose interglitch behaviour is characterized by a large second derivative. With the vortex unpinning model for glitches, if we adopt the hypothesis that the number of vortices unpinned in each glitch and the moment of inertia of the crust superfluid involved in the interglitch response are the same in Geminga as in Vela, we find that the expected interglitch second derivative in Geminga agrees with that of the COS-B ephemeris.

Subject Keywords

Pulsar glitches, Geminga

URI

https://hdl.handle.net/11511/66256

Journal

ASTRONOMY & ASTROPHYSICS

Collections

Department of Physics, Article

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Citation Formats

M. ALPAR, H. OGELMAN, and J. SHAHAM, “IS GEMINGA A GLITCHING PULSAR,” ASTRONOMY & ASTROPHYSICS, pp. 0–0, 1993, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66256.