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Related papers: Electron-Capture Isotopes could Constrain Cosmic-R…

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The Boron to Carbon (B/C) and sub-Fe/Fe ratios provides an important clue on Cosmic Ray (CR) propagation within the Galaxy. These ratios estimate the grammage that the CR traverse as they propagate from their sources to Earth. Attempts to…

High Energy Astrophysical Phenomena · Physics 2016-07-27 David Benyamin , Ehud Nakar , Tsvi Piran , Nir j. Shaviv

Electron-capture (EC) unstable species in Galactic cosmic rays constrain the time elapsed between nucleosynthesis and acceleration. They have also been advocated as tracers of reacceleration or gas inhomogeneities during their transport.…

High Energy Astrophysical Phenomena · Physics 2026-02-09 M. Borchiellini , D. Maurin , M. Vecchi

The abundance of Li, Be, and B isotopes in galactic cosmic rays (GCR) between E=50-200 MeV/nucleon has been observed by the Cosmic Ray Isotope Spectrometer (CRIS) on NASA's ACE mission since 1997 with high statistical accuracy. Precise…

Models for cosmic ray (CR) dynamics fundamentally depend on the rate of CR scattering from magnetic fluctuations. In the ISM, for CRs with energies ~MeV-TeV, these fluctuations are usually attributed either to 'extrinsic turbulence' (ET) -…

High Energy Astrophysical Phenomena · Physics 2022-11-10 Philip F. Hopkins , Jonathan Squire , Iryna S. Butsky , Suoqing Ji

Recent measurements of the cosmic ray (CR) antiproton flux have been shown to challenge existing CR propagation models. It was shown that the reacceleration models designed to match secondary to primary nuclei ratios (e.g., B/C) produce too…

Astrophysics · Physics 2010-05-27 I. V. Moskalenko , A. W. Strong , J. F. Ormes , S. G. Mashnik

Recent cosmic ray (CR) measurements have revealed unexpected anomalies in secondary CRs, namely deviations from the predictions of the so-called standard Galactic CR paradigm regarding the composition and energy spectra of the products of…

High Energy Astrophysical Phenomena · Physics 2024-10-30 Rui-zhi Yang , Felix Aharonian

We have previously focused on studying the electron-capture isotopes within the dynamic spiral-arms model and empirically derived the energy dependence of the electron attachment rate using the observation of $^{49}$Ti/$^{49}$V and…

High Energy Astrophysical Phenomena · Physics 2018-08-22 David Benyamin , Nir J. Shaviv

The nature of cosmic rays (CRs) and cosmic ray transport in galaxy clusters is probed by a number of observations. Radio observations reveal the synchrotron radiation of cosmic ray electrons (CRe) spiraling around cluster magnetic fields.…

High Energy Astrophysical Phenomena · Physics 2019-06-26 Joshua Wiener , Ellen G. Zweibel

During the late stages of gravitational core-collapse of massive stars, extreme isospin asymmetries are reached within the core. Due to the lack of microscopic calculations of electron capture (EC) rates for all relevant nuclei, in general…

Nuclear Theory · Physics 2017-02-22 Ad. R. Raduta , F. Gulminelli , M. Oertel

Based on the diffusion-halo model for cosmic-ray (CR) propagation, including stochastic reacceleration due to collisions with hydromagnetic turbulence, we study the behavior of the electron component and the diffuse $\gamma$-rays…

High Energy Astrophysical Phenomena · Physics 2011-01-27 T. Shibata , T. Ishikawa , S. Sekiguchi

Recent measurements of the cosmic ray (CR) antiproton flux have been shown to challenge existing CR propagation models. It was shown that the reacceleration models designed to match secondary to primary nuclei ratios (e.g., boron/carbon)…

Astrophysics · Physics 2009-11-07 I. V. Moskalenko , A. W. Strong , S. G. Mashnik , J. F. Ormes

Electron capture (EC) decay relies on attachment and stripping cross-sections, that in turn, depend on the atomic number of the nucleus. We revisit the impact of EC decay in the context of the high-precision cosmic-ray fluxes measured by…

High Energy Astrophysical Phenomena · Physics 2023-09-25 M. Borchiellini , D. Maurin , M. Vecchi

The ACE-CRIS collaboration has recently released the measurement of radioactive $^{60}$Fe nuclei abundance in Galactic Cosmic Rays, in the energy range $\sim 195-500$ MeV per nucleon. We model Cosmic Ray propagation and derive from this…

High Energy Astrophysical Phenomena · Physics 2020-04-29 Giovanni Morlino , Elena Amato

The impact of electron-capture (EC) cross sections on neutron-rich nuclei on the dynamics of core-collapse during infall and early post-bounce is studied performing spherically symmetric simulations in general relativity using a multigroup…

High Energy Astrophysical Phenomena · Physics 2020-01-22 Aurélien Pascal , Simon Giraud , Anthea Fantina , Francesca Gulminelli , Jerome Novak , Micaela Oertel , Adriana Raduta

Cosmic rays (CR) propagate through the galactic scales down to the smaller scales at which stars form. CRs are close to energy equipartition with the other components of the interstellar medium and can provide a support against gravity if…

Astrophysics of Galaxies · Physics 2019-02-13 Benoît Commerçon , Alexandre Marcowith , Yohan Dubois

Electron capture rates on \emph{fp}-shell nuclei play a pivotal role in the dynamics of stellar evolution and core collapse. These rates play a crucial role in the gravitational collapse of the core of a massive star activating the…

Nuclear Theory · Physics 2025-05-05 Muhammad Majid , Jameel-Un Nabi

Understanding the acceleration of Ultra High Energy Cosmic Rays is one of the great challenges of contemporary astrophysics. In this short review, we summarize the general observational constraints on their composition, spectrum and…

High Energy Astrophysical Phenomena · Physics 2023-05-24 Noemie Globus , Roger Blandford

We constrain the energy at which the transition from Galactic to extragalactic cosmic rays occurs by computing the anisotropy at Earth of cosmic rays emitted by Galactic sources. Since the diffusion approximation starts to loose its…

High Energy Astrophysical Phenomena · Physics 2012-07-17 G. Giacinti , M. Kachelriess , D. V. Semikoz , G. Sigl

We construct a Galactic cosmic ray (CR) diffusion model while considering that CR sources reside predominantly in the Galactic spiral arms. We find that the CR flux (CRF) reaching the solar system should periodically increase each crossing…

Astrophysics · Physics 2008-11-26 Nir J. Shaviv

The energy spectra of primary and secondary cosmic rays (CR) generally harden at several hundreds of GeV, which can be naturally interpreted by propagation effects. We adopt a spatially dependent CR propagation model to fit the spectral…

High Energy Astrophysical Phenomena · Physics 2022-06-22 Meng-Jie Zhao , Kun Fang , Xiao-Jun Bi
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