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X-rays

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Faint X‐Ray Structure In The Crab Pulsar Wind Nebula, F. D. Seward, W. H. Tucker, R. A. Fesen Dec 2006

Faint X‐Ray Structure In The Crab Pulsar Wind Nebula, F. D. Seward, W. H. Tucker, R. A. Fesen

Dartmouth Scholarship

We report on a Chandra observation of the Crab Nebula that gives the first clear view of the faint boundary of the Crab's X-ray-emitting pulsar wind nebula. There is structure in all directions. Fingers, loops, bays, and the south pulsar jet all indicate that either filamentary material or the magnetic field is controlling the relativistic electrons. In general, spectra soften as distance from the pulsar increases but do not change rapidly along linear features. This is particularly true for the pulsar jet. The termination of the jet is abrupt; the east side is close to an [O III] optical filament, …


Chandra Observations Of The Luminous, Oxygen‐Rich Supernova Remnants In The Irregular Galaxy Ngc 4449, Daniel J. Patnaude, Robert A. Fesen Apr 2003

Chandra Observations Of The Luminous, Oxygen‐Rich Supernova Remnants In The Irregular Galaxy Ngc 4449, Daniel J. Patnaude, Robert A. Fesen

Dartmouth Scholarship

An analysis of a 29 ks Chandra ACIS-S observation of the young, Cassiopeia A–like supernova remnant in the irregular galaxy NGC 4449 is presented. The observed 0.5–2.1 keV spectrum reveals the likely presence of several emission lines. A nonequilibrium ionization fit to the spectrum suggests an overabundance of oxygen around 20 times solar, consistent with the remnant’s UV and optical emission-line properties. We discuss the remnant’s approximate X-ray–derived elemental abundances and compare its X-ray spectrum and luminosity with other oxygen-rich remnants