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Title: On the Origin of Observed Cosmic-Ray Spectrum Below 100 TV
Abstract Recent precise measurements of primary and secondary cosmic-ray (CR) species in the teravolt rigidity domain have unveiled a bump in their spectra, located between 0.5 and 50 TV. We argue that a local shock may generate such a bump by increasing the rigidity of the preexisting CRs below 50 TV by a mere factor of ∼1.5. Reaccelerated particles below ∼0.5 TV are convected with the interstellar medium flow and do not reach the Sun, thus creating the bump. This single universal process is responsible for the observed spectra of all CR species in the rigidity range below 100 TV. We propose that one viable shock candidate is the Epsilon Eridani star at 3.2 pc from the Sun, which is well aligned with the direction of the local magnetic field. Other shocks, such as old supernova shells, may produce a similar effect. We provide a simple formula, Equation (9), that reproduces the spectra of all CR species with only two nonadjustable shock parameters, uniquely derived from the proton data. We show how our formalism predicts helium and carbon spectra and the B/C ratio.  more » « less
Award ID(s):
2109103
PAR ID:
10368606
Author(s) / Creator(s):
;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
933
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 78
Size(s):
Article No. 78
Sponsoring Org:
National Science Foundation
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