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arXiv · astro-ph/0604097

The XMM-Newton view of the Crab

M. G. F. Kirsch·G. Schoenherr·E. Kendziorra·M. J. Freyberg·M. Martin·J. Wilms·K. Mukerjee·M. G. Breitfellner·M. J. S. Smith·R. Staubert
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Abstract

We discuss the current X-ray view of the Crab Nebula and Pulsar, summarising our analysis of observations of the source with the EPIC-pn camera on board the XMM-Newton observatory. Different modes of EPIC-pn were combined in order to yield a complete scenario of the spectral properties of the Crab resolved in space and time (pulse phase). In addition we give a description of the special EPIC-pn Burst mode and guidance for data reduction in that mode. We analysed spectra for the nebula and pulsar separately in the 0.6-12.0 keV energy band. All data were processed with the SAS 6.0.0 XMM-Newton Scientific Analysis System package; models were fitted to the data with XSPEC 11. The high time resolution of EPIC-pn in its Burst mode (7 micros) was used for a phase resolved analysis of the pulsar spectrum, after determination of the period with epoch folding techniques. Data from the Small Window mode were processed and corrected for pile-up allowing for spectroscopy simultaneously resolved in space and time. The spatial variation of the spectrum over the entire region of the Crab shows a gradual spectral softening from the inner pulsar region to the outer nebula region with a variation in photon index, Gamma, from 2.0 to 2.4. Pulse phase resolved spectroscopy of the Crab Pulsar reveals a phase dependent modulation of the photon index in form of a significant hardening of the spectrum in the inter-peak phase from Gamma =1.7 during the pulse peak to Gamma =1.5.

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M. G. F. Kirsch, G. Schoenherr, E. Kendziorra, M. J. Freyberg, M. Martin, J. Wilms, K. Mukerjee, M. G. Breitfellner, M. J. S. Smith, R. Staubert. 2006-04-05. The XMM-Newton view of the Crab. https://doi.org/10.1051/0004-6361%3A20054783

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