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Constraining the IMF using TeV gamma ray absorption

J. S. Bullock·R. S. Somerville·D. MacMinn·J. R. Primack
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Abstract

Gamma rays of ~TeV energies from distant sources suffer attenuation due to pair production off of ~1 micron EBL photons. We may exploit this process in order to indirectly measure the EBL and constrain models of galaxy formation. Here, using semi-analytic models of galaxy formation, we examine how gamma ray absorption may be used as an indirect probe of the stellar initial mass function (IMF), although there is a degeneracy with dust modeling. We point out that with the new generation of gamma ray telescopes including STACEE, MAGIC, HESS, VERITAS, and Milagro, we should soon possess a wealth of new data and a new method for probing the nature of the IMF.

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J. S. Bullock, R. S. Somerville, D. MacMinn, J. R. Primack. 1998-12-20. Constraining the IMF using TeV gamma ray absorption. https://doi.org/10.1016/s0927-6505(99)00033-x

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