학술논문
TeV halos and the role of pulsar wind nebulae as sources of cosmic ray positrons
Document Type
Working Paper
Source
Subject
Language
Abstract
The recent detection of the Geminga PWN by HAWC in the multi-TeV band allows us to infer precious information about the transport of pairs in the immediate surroundings of the pulsar and on the spectrum of pairs contributed by a Geminga-like pulsar to the spectrum of pairs in the cosmic radiation. Moreover, this detection allows us to address the issue of how typical are the so-called TeV halos associated to PWNe. Our calculations confirm the need to have suppressed diffusion in a region of at least $20-50\,$pc around the pulsar, and are used here to infer precious constraints on the spectrum of pairs accelerated at the termination shock: more specifically, we discuss the conditions under which such a spectrum is consistent with that typically expected in a PWN and how it gets modified once it escapes the halo. Finally, we discuss the implications of the existence of a TeV halo around Geminga in terms of acceleration of protons in the pulsar environment, a topic of profound relevance for the whole field of particle acceleration and physics of pulsars.
Comment: 15 pages, accepted for publication in PRD
Comment: 15 pages, accepted for publication in PRD