A local fading accelerator and the origin of TeV cosmic ray electrons

Discussion timeslot (ZOOM-Meeting): 15. July 2021 - 18:00
ZOOM-Meeting URL: https://desy.zoom.us/j/91896950007
ZOOM-Meeting ID: 91896950007
ZOOM-Meeting Passcode: ICRC2021
Corresponding Session: https://icrc2021-venue.desy.de/channel/16-Cosmic-Ray-Antiparticles-and-Electrons-CRD-DM-GAD-MM/128
Live-Stream URL: https://icrc2021-venue.desy.de/livestream/Discussion-06/7

Abstract:
'The total cosmic ray electron spectrum (electrons plus positrons) exhibits a break at a particlernenergy of ∼ 1 TeV and extends without any attenuation up to ∼ 20 TeV. Synchrotron and inversernCompton energy losses strongly constrain both the age and the distance of the potential sources ofrnTeV and multi-TeV electrons to ≈ $10^5$ yr and ≈ 100 − 500 pc, depending on both the absolute valuernand energy dependence of the cosmic ray diffusion coefficient. This suggests that only a few, or justrnone nearby discrete source may explain the observed spectrum of high energy electrons. On thernother hand the measured positron fraction, after initially increasing with particle energy, saturatesrnat a level well below 0.5 and likely drops above ∼ 400−500 GeV. This means that the local source(s)rnof TeV electrons should not produce positrons in equal amount, ruling out scenarios involvingrnpulsars/pulsar winds as the main sources of high energy leptons. In this paper we show that arnsingle, local, and fading source can naturally account for the entire spectrum of cosmic ray electronsrnin the TeV domain. Even though the nature of such source remains unclear, we discuss knownrncosmic ray accelerators, such as supernova remnant and stellar wind shocks, which are believed tornaccelerate preferentially electrons rather than positrons.'

Authors: Sarah Recchia | Stefano Gabici | Felix Aharonian | Jacco Vink
Indico-ID: 951
Proceeding URL: https://pos.sissa.it/395/168