Cerenkov Line Emission as a Possible Mechanism of X-ray Lines in Gamma-ray Bursts
نویسندگان
چکیده
The recent discoveries of X-ray lines in the afterglows of gamma-ray bursts (GRBs) provide significant clues to the nature of GRB progenitors and central environments. However, the iron line interpretation by fluorescence or recombination mechanism involves the request for the large amount of iron material. We argue that the very strong iron line could be attributed to an alternative mechanism: Cerenkov line emission. Therefore, line intensity will be nearly independent of the iron abundance, then the medium with the anomaly high Fe abundance is not required. Subject headings: gamma-rays: bursts line: profiles X-rays: general
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