The Crab glitches : incidence and cumulative effect

نویسندگان

  • F. Graham Smith
  • C. Jordan
چکیده

The fourteen glitches observed during 33 years do not show the simple pattern expected from a relaxation oscillator. They may however be regarded as three major events separated by about 12 years, the third being a group of smaller glitches. There is a step increase in slowdown rate at each glitch, whose cumulative effect makes a significant contribution to the second differentiaï ν. The braking index n has previously been evaluated only between glitches: the effect of the glitches is to reduce n from 2.51 to 2.45. This extra effect due to the glitches would be explained by an increase in dipole field at the fractional rate of 1.5 × 10 −5 per annum.

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تاریخ انتشار 2003