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Accelerated expansion of the Crab Nebula and evaluation of its neutron-star parameters

M. Bejger·P. Haensel
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Abstract

A model of an accelerated expansion of the Crab Nebula powered by the spinning-down Crab pulsar is proposed, in which time dependence of the acceleration is connected with evolution of pulsar luminosity. Using recent observational data, we derive estimates of the Crab neutron-star moment of inertia. Correlations between the neutron star moment of inertia and its mass and radius allow for rough estimates of the Crab neutron-star radius and mass. In contrast to the previously used constant-acceleration approximation, even for the expanding nebula mass ~7 M_sun results obtained within our model do not stay in conflict with the modern stiff equations of state of dense matter.

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M. Bejger, P. Haensel. 2003-03-19. Accelerated expansion of the Crab Nebula and evaluation of its neutron-star parameters. https://doi.org/10.1051/0004-6361%3A20030642

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