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arXiv · 0810.2784

TeV Gamma Rays from Geminga and the Origin of the GeV Positron Excess

Hasan Yuksel·Matthew D. Kistler·Todor Stanev
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Abstract

The Geminga pulsar has long been one of the most intriguing MeV-GeV gamma-ray point sources. We examine the implications of the recent Milagro detection of extended, multi-TeV gamma-ray emission from Geminga, finding that this reveals the existence of an ancient, powerful cosmic-ray accelerator that can plausibly account for the multi-GeV positron excess that has evaded explanation. We explore a number of testable predictions for gamma-ray and electron/positron experiments (up to ~100 TeV) that can confirm the first "direct" detection of a cosmic-ray source.

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Hasan Yuksel, Matthew D. Kistler, Todor Stanev. 2008-10-16. TeV Gamma Rays from Geminga and the Origin of the GeV Positron Excess. https://doi.org/10.1103/physrevlett.103.051101

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