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The young oxygen-rich supernova remnant E0102-72 in the Small Magellanic Cloud has been observed with the High Energy Transmission Grating Spectrometer of Chandra. The high resolution X-ray spectrum reveals images of the remnant in the light of individual emission lines of oxygen, neon, magnesium and silicon. The peak emission region for hydrogen-like ions lies at larger radial distance from the SNR center than the corresponding helium-like ions, suggesting passage of the ejecta through the reverse shock. We examine models which test this interpretation, and we discuss the implications.
The High Energy Transmission Grating (HETG) Spectrometer aboard the Chandra X-Ray Observatory was used to observe E0102-72, a ~1000 year old, oxygen rich supernova in the Small Magellanic Cloud. The HETG disperses the image of the remnant into a spec
We present extensive radio and millimeter observations of the unusually bright GRB 130427A at z=0.340, spanning 0.67 to 12 days after the burst. Taken in conjunction with detailed multi-band UV, optical, NIR, and X-ray observations we find that the b
We present comprehensive multiwavelength radio to X-ray observations of GRB 181201A spanning from $approx150$ s to $approx163$ days after the burst, comprising the first joint ALMA-VLA-GMRT observations of a gamma-ray burst (GRB) afterglow. The radio
The Schweizer-Middleditch star, located behind the SN 1006 remnant and near its center in projection, provides the opportunity to study cold, expanding ejecta within the SN 1006 shell through UV absorption. Especially notable is an extremely sharp re
We present observations with VLT and HST of the broad emission lines from the inner ejecta and reverse shock of SN 1987A from 1999 until 2012 (days 4381 -- 9100 after explosion). We detect broad lines from H-alpha, H-beta, Mg I], Na I, [O I], [Ca II]