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arXiv · 1010.4167

X-ray pulsations from the radio-quiet gamma-ray pulsar in CTA 1

P. A. Caraveo·A. De Luca·M. Marelli·G. F. Bignami·P. S. Ray·P. M. Saz-Parkinson·G. Kanbach
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Abstract

Prompted by the Fermi LAT discovery of a radio-quiet gamma-ray pulsar inside the CTA 1 supernova remnant, we obtained a 130 ks XMM-Newton observation to assess the timing behavior of this pulsar. Exploiting both the unprecedented photon harvest and the contemporary Fermi LAT timing measurements, a 4.7 sigma single peak pulsation is detected, making PSR J0007+7303 the second example, after Geminga, of a radio-quiet gamma-ray pulsar also seen to pulsate in X-rays. Phase-resolved spectroscopy shows that the off-pulse portion of the light curve is dominated by a power-law, non-thermal spectrum, while the X-ray peak emission appears to be mainly of thermal origin, probably from a polar cap heated by magnetospheric return currents, pointing to a hot spot varying throughout the pulsar rotation.

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P. A. Caraveo, A. De Luca, M. Marelli, G. F. Bignami, P. S. Ray, P. M. Saz-Parkinson, G. Kanbach. 2010-10-20. X-ray pulsations from the radio-quiet gamma-ray pulsar in CTA 1. https://doi.org/10.1088/2041-8205%2F725%2F1%2Fl6

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