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تسجيل مستخدم جديدOn the origin of observed cosmic ray spectrum below 100 TV
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Significant progress in cosmic ray (CR) studies was achieved over the past decade. Particularly important are precise measurements of primary and secondary species in the TV rigidity domain that show a bump in the spectra of CR species from 0.5-50 TV. In this letter, we argue that it is likely caused by a stellar bow- or wind-termination shock that reaccelerates preexisting CRs, which further propagate to the Sun along the magnetic field lines. This single universal process is responsible for the observed spectra of all CR species in the rigidity range below 100 TV. A viable candidate is Epsilon Eridani star at 3.2 pc from the Sun, which is well-aligned with the direction of the local magnetic field. We provide a simple formula 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.
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