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arXiv · 1404.7546

What could we learn from a sharply falling positron fraction?

Timur Delahaye·Kumiko Kotera·Joseph Silk
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Abstract

Recent results from the AMS-02 data have confirmed that the cosmic ray positron fraction increases with energy between 10 and 200GeV. This quantity should not exceed 50%, and it is hence expected that it will either converge towards 50% or fall. We study the possibility that future data may show the positron fraction dropping down abruptly to the level expected with only secondary production, and forecast the implications of such a feature in term of possible injection mechanisms that include both dark matter and pulsars. {Were a sharp steepening to be found, rather surprisingly, we conclude that pulsar models would do at least as well as dark matter scenarios in terms of accounting for any spectral cut-off.

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Timur Delahaye, Kumiko Kotera, Joseph Silk. 2014-04-29. What could we learn from a sharply falling positron fraction?. https://doi.org/10.1088/0004-637x/794/2/168

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