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ROSAT HRI Observations of the Crab Pulsar: An Improved Temperature upper limit for PSR 0531+21

W. Becker·B. Aschenbach
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Abstract

ROSAT HRI observations have been used to determine an upper limit of the Crab pulsar surface temperature from the off-pulse count rate. For a neutron star mass of 1.4 \Mo and a radius of 10 km as well as the standard distance and interstellar column density, the redshifted temperature upper limit is\/ $T_s^\infty \le 1.55\times 10^6$ K $(3σ)$. This is the lowest temperature upper limit obtained for the Crab pulsar so far. Slightly different values for $T_s^\infty$ are computed for the various neutron star models available in the literature, reflecting the difference in the equation of state.

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W. Becker, B. Aschenbach. 1995-03-02. ROSAT HRI Observations of the Crab Pulsar: An Improved Temperature upper limit for PSR 0531+21. https://arxiv.org/abs/astro-ph/9503012

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