title: Discovery of Spatial and Spectral Structure in the X-Ray Emission from the Crab Nebula.
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) readout 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.
authors.initials: MC
authors.lastname: Weisskopf
authors.initials: JJ
authors.lastname: Hester
authors.initials: AF
authors.lastname: Tennant
authors.initials: RF
authors.lastname: Elsner
authors.initials: NS
authors.lastname: Schulz
authors.initials: HL
authors.lastname: Marshall
authors.initials: M
authors.lastname: Karovska
authors.initials: JS
authors.lastname: Nichols
authors.initials: DA
authors.lastname: Swartz
authors.initials: JJ
authors.lastname: Kolodziejczak
authors.initials: SL
authors.lastname: O'Dell