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.
@article{arxiv.1010.4167,
title = {X-ray pulsations from the radio-quiet gamma-ray pulsar in CTA 1},
author = {P. A. Caraveo and A. De Luca and M. Marelli and G. F. Bignami and P. S. Ray and P. M. Saz-Parkinson and G. Kanbach},
journal= {arXiv preprint arXiv:1010.4167},
year = {2015}
}
Comments
19 pages, 4 figures. Accepted for publication in ApJ Letters