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arXiv · astro-ph/0304295

Evidence of TeV gamma-ray emission from the nearby starburst galaxy NGC 253

C. Itoh·R. Enomoto·S. Yanagita·T. Yoshida·T. Tanimori·K. Okumura·CANGAROO-II collaboration
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Abstract

TeV gamma-rays were recently detected from the nearby normal spiral galaxy NGC 253 (Itoh et al., 2002). Observations to detect the Cherenkov light images initiated by gamma-rays from the direction of NGC 253 were carried out in 2000 and 2001 over a total period of $\sim$150 hours. The orientation of images in gamma-ray--like events is not consistent with emission from a point source, and the emission region corresponds to a size greater than 10 kpc in radius. Here, detailed descriptions of the analysis procedures and techniques are given.

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C. Itoh, R. Enomoto, S. Yanagita, T. Yoshida, T. Tanimori, K. Okumura, CANGAROO-II collaboration. 2003-04-16. Evidence of TeV gamma-ray emission from the nearby starburst galaxy NGC 253. https://doi.org/10.1051/0004-6361%3A20030247

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