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Physical Sciences and Mathematics Commons

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Astrophysics and Astronomy

2004

Emission line

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Signature Of Electron Capture In Iron‐Rich Ejecta Of Sn 2003du, Peter Hoflich, Christopher L. Gerardy, Ken-Ichi Nomoto, Kentaro Motohara, Robert A. Fesen Dec 2004

Signature Of Electron Capture In Iron‐Rich Ejecta Of Sn 2003du, Peter Hoflich, Christopher L. Gerardy, Ken-Ichi Nomoto, Kentaro Motohara, Robert A. Fesen

Dartmouth Scholarship

Late-time near-infrared and optical spectra of the normal-bright Type Ia supernova 2003du about 300 days after the explosion are presented. At this late epoch, the emission profiles of well-isolated [Fe II] lines (in particular that of the strong 1.644 μm feature) trace out the global kinematic distribution of radioactive material in the expanding supernova ejecta. In SN 2003du, the 1.644 μm [Fe II] line seems to show a flat-topped profile, indicative of a thick but hollow-centered expanding shell, rather than a strongly peaked profile that would be expected from a "center-filled" distribution. Based on detailed models for exploding Chandrasekhar-mass white …


Location Of The Optical Reverse Shock In The Cassiopeia A Supernova Remnant, Jon A. Morse, Robert A. Fesen, Roger A. Chevalier, Kazimierz J. Borkowski Oct 2004

Location Of The Optical Reverse Shock In The Cassiopeia A Supernova Remnant, Jon A. Morse, Robert A. Fesen, Roger A. Chevalier, Kazimierz J. Borkowski

Dartmouth Scholarship

We use two epochs of Hubble Space Telescope WFPC2 images separated by 2 yr to determine the location and propagation of the reverse shock (RS) in the young supernova remnant Cassiopeia A (Cas A). The images trace optical line emission from fast-moving knots and filaments of highly processed ejecta as they cross the RS, become heated and compressed, and radiatively cool. At numerous positions around the optical shell, new emission features are seen in the 2002 images that were not yet visible in the 2000 exposures. In a few instances emission features seen in the first epoch have completely disappeared …