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Title: HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess

Abstract

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.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4]
  1. Fermilab
  2. Johns Hopkins U.
  3. Ohio State U., CCAPP
  4. Maryland U.
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1350509
Report Number(s):
arXiv:1702.08436; FERMILAB-PUB-17-061-A
Journal ID: ISSN 2470-0010; 1515183
DOE Contract Number:  
AC02-07CH11359
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review D; Journal Volume: 96
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Hooper, Dan, Cholis, Ilias, Linden, Tim, and Fang, Ke. HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess. United States: N. p., 2017. Web. doi:10.1103/PhysRevD.96.103013.
Hooper, Dan, Cholis, Ilias, Linden, Tim, & Fang, Ke. HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess. United States. doi:10.1103/PhysRevD.96.103013.
Hooper, Dan, Cholis, Ilias, Linden, Tim, and Fang, Ke. Fri . "HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess". United States. doi:10.1103/PhysRevD.96.103013. https://www.osti.gov/servlets/purl/1350509.
@article{osti_1350509,
title = {HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess},
author = {Hooper, Dan and Cholis, Ilias and Linden, Tim and Fang, Ke},
abstractNote = {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.},
doi = {10.1103/PhysRevD.96.103013},
journal = {Physical Review D},
number = ,
volume = 96,
place = {United States},
year = {Fri Nov 17 00:00:00 EST 2017},
month = {Fri Nov 17 00:00:00 EST 2017}
}