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56Co gamma-rays from SN1998bu: COMPTEL upper limits

S. Plueschke·R. Georgii·R. Diehl·W. Collmar·G. Lichti·V. Schoenfelder·H. Bloemen·K. Bennett·M. McConnell·J. Ryan
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Abstract

The type Ia supernova SN1998bu in M96 was observed by COMPTEL for a total of 88 days starting 17 days after the first detection of the supernova. The accumulated effective observation time was 4.14 Msec. The COMPTEL observations were performed in a special instrument mode improving the low-energy sensitivity. We generated images in the 847 keV and 1238 keV lines of 56Co, using improved point spread functions for the low-energy mode. We do not detect SN1998bu. A spectral analysis of our data also confirms the non-detection of the supernova. We discuss the event for which our upper limits constrain the standard supernova models.

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S. Plueschke, R. Georgii, R. Diehl, W. Collmar, G. Lichti, V. Schoenfelder, H. Bloemen, K. Bennett, M. McConnell, J. Ryan. 2001-04-03. 56Co gamma-rays from SN1998bu: COMPTEL upper limits. https://arxiv.org/abs/astro-ph/0104049

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