HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess
Author | : |
Publisher | : |
Total Pages | : |
Release | : 2017 |
ISBN-10 | : OCLC:986148682 |
ISBN-13 | : |
Rating | : 4/5 ( Downloads) |
Download or read book HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent measurements of the Geminga and B0656+14 pulsars by the gamma-ray telescope HAWC (along with earlier measurements by Milagro) indicate that these objects generate significant fluxes of very high-energy electrons. In this paper, we use the very high-energy gamma-ray intensity and spectrum of these pulsars to calculate and constrain their expected contributions to the local cosmic-ray positron spectrum. Among models that are capable of reproducing the observed characteristics of the gamma-ray emission, we find that pulsars invariably produce a flux of high-energy positrons that is similar in spectrum and magnitude to the positron fraction measured by PAMELA and AMS-02. In light of this result, we conclude that it is very likely that pulsars provide the dominant contribution to the long perplexing cosmic-ray positron excess.