New light on the X-ray spectrum of the Crab Nebula

XMM-Newton observations of the Crab provide new information on its integrat ed X-ray spectrum and the variation of the spectral form across the nebula. The Cr ab pulsar and its surrounding torus exhibit the hardest spectra wit h power-law indices of Gamma = 1.6 and 1.8. The jet and outer reaches of th e nebula are significantly softer with Gamma = 2.1 and 2.3 respectively. Fo r the whole nebula, the huge number of recorded counts allows a detailed ex amination of the soft X-ray absorption due to cool gas in the foreground of the Crab. Absorption edges due to oxygen and neon are clearly identified. Oxygen and iron in the interstellar medium are underabundant by a factor of 0.63 +/- 0.01. The average N-H = 3.45 +/- 0.02 10(21) cm(-2) and varies by less than +/-11% on a scale equal to or larger than 20 arcsec over the fac e of the nebula. These observations of the Crab provide an excellent demons tration of the power of the EPIC cameras on XMM-Newton for spatial, spectra l and timing studies.