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Phase-resolved spectroscopy of Geminga shows rotating hot spot(s)

P. A. Caraveo·A. De Luca·S. Mereghetti·A. Pellizzoni·G. F. Bignami
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Abstract

Isolated neutron stars are seen in x-rays through their nonthermal and/or surface thermal emissions. XMM-Newton observations of the Geminga pulsar show a 43 electron volt spectrum from the whole neutron star surface, as well as a power-law component above 2 kiloelectron volts. In addition, we have detected a hot (170 electron volts) thermal emission from an 60-meter-radius spot on the pulsar s surface. Such a thermal emission, only visible at selected phase intervals, may be coming from polar hot spot(s), long thought to exist as a result of heating from magnetospheric accelerated particles. It may provide the missing link between the x-ray and gamma-ray emission of the pulsar.

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P. A. Caraveo, A. De Luca, S. Mereghetti, A. Pellizzoni, G. F. Bignami. 2004-07-19. Phase-resolved spectroscopy of Geminga shows rotating hot spot(s). https://doi.org/10.1126/science.1097173

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