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Discovery of Spatial and Spectral Structure in the X-Ray Emission from the Crab Nebula

Martin C. Weisskopf·J. Jeff Hester·Allyn F. Tennant·Ronald F. Elsner·Norbert S. Schulz·Herman L. Marshall·Margarita Karovska·Joy S. Nichols·Douglas A. Swartz·Jeffery J. Kolodziejczak·Stephen L. O'Dell
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Abstract

The Chandra X-ray Observatory observed the Crab Nebula and Pulsar during orbital calibration. Zeroth-order images with the High-Energy Transmission Grating (HETG) read-out by the Advanced CCD Imaging Spectrometer spectroscopy array (ACIS-S) show a striking richness of x-ray structure, at a resolution comparable to that of the best ground-based visible-light observations. The HETG--ACIS-S images reveal, for the first time, an x-ray inner ring within the x-ray torus, the suggestion of a hollow-tube structure for the torus, and x-ray knots along the inner ring and (perhaps) along the inward extension of the x-ray jet. Although complicated by instrumental effects and the brightness of the Crab Nebula, the spectrometric analysis shows systematic variations of the x-ray spectrum throughout the Nebula.

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Martin C. Weisskopf, J. Jeff Hester, Allyn F. Tennant, Ronald F. Elsner, Norbert S. Schulz, Herman L. Marshall, Margarita Karovska, Joy S. Nichols, Douglas A. Swartz, Jeffery J. Kolodziejczak, Stephen L. O'Dell. 2000-04-11. Discovery of Spatial and Spectral Structure in the X-Ray Emission from the Crab Nebula. https://doi.org/10.1086/312733

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