Intermediate mass and heavy Galactic cosmic-ray nuclei: the case of new AMS-02 measurements

Abstract

The recent measurement of the spectra of intermediate mass nuclei and iron nuclei carried out with the AMS-02 experiment provided us with the most complete set of data on cosmic ray fluxes to date, and allowed us to test the standard model for the transport of these particles through the Galaxy to the finest details. We show that the parameters derived from lighter primary and secondary elements in the cosmic radiation also lead to a good description of the data on heavier nuclei, with no need to invoke different injection spectra for such nuclei, provided the whole chain of fragmentation is properly accounted for. The only exception to this finding is represented by iron nuclei, which show a very unusual trend at rigidity $\lesssim 100$ GV. This trend reflects in a Fe/O ratio that is at odds with the results of the standard model of cosmic ray transport, and is in contradiction with data collected by HEAO, ACE-CRIS and Voyager at lower energy. We speculate on possible origins of such findings.

12 pages, 8 figures, Accepted for publication on Physical Review D

References in corpus (23)

• The origin of the positron excess in cosmic rays
• Spectral breaks as a signature of cosmic ray induced turbulence in the Galaxy
• Origin of the Cosmic Ray Spectral Hardening
• Measurement of boron and carbon fluxes in cosmic rays with the PAMELA experiment
• High-energy antiprotons from old supernova remnants
• Galactic cosmic rays after the AMS-02 observations
• AMS-02 beryllium data and its implication for cosmic ray transport
• Composition of Primary Cosmic-Ray Nuclei at High Energies
• Indications for a high-rigidity break in the cosmic-ray diffusion coefficient
• Inference of the Local Interstellar Spectra of Cosmic Ray Nuclei Z<=28 with the GalProp-HelMod Framework
• Spallation Residues in the Reaction 56Fe + p at 0.3, 0.5, 0.75, 1.0 and 1.5 A GeV
• The low rate of Galactic pevatrons
• Galactic factories of cosmic-ray electrons and positrons
• Galactic halo size in the light of recent AMS-02 data
• Combined analysis of AMS-02 (Li,Be,B)/C, N/O, 3He, and 4He data
• Direct Measurement of the Cosmic-Ray Carbon and Oxygen Spectra from 10 GeV$/n$ to 2.2 TeV$/n$ with the Calorimetric Electron Telescope on the International Space Station
• Contribution of pulsars to cosmic-ray positrons in light of recent observation of inverse-Compton halos
• Cosmic ray production in supernova remnants including reacceleration: the secondary to primary ratio
• Dark matter or correlated errors: Systematics of the AMS-02 antiproton excess
• Cosmic-ray database update: ultra-high energy, ultra-heavy, and anti-nuclei cosmic-ray data (CRDB v4.0)
• On the spectrum of stable secondary nuclei in cosmic rays
• Effects of reacceleration and source grammage on secondary cosmic rays spectra
• Impact of transport modelling on the ${}^{60}$Fe abundance inside Galactic cosmic ray sources

Cited by in corpus (13)

• The Origin of Galactic Cosmic Rays as Revealed by their Composition
• Constraints on the spatially dependent cosmic-ray propagation model from Bayesian Analysis
• Testing the universality of cosmic-ray nuclei from protons to oxygen with AMS-02
• A simple determination of the halo size $L$ from ${}^{10}$Be/${}^9$Be data
• New determination of the production cross section for secondary positrons and electrons in the Galaxy
• TeV halos and the role of pulsar wind nebulae as sources of cosmic ray positrons
• Constraining dark matter annihilation with cosmic ray antiprotons using neural networks
• The rigidity dependence of galactic cosmic-ray fluxes and its connection with the diffusion coefficient
• Weighing the Local Interstellar Medium using Gamma Rays and Dust
• The Origin of the Very-High-Energy Diffuse $\gamma$-Ray Emission: The Case for Galactic Source Cocoons
• Transport parameters from AMS-02 F/Si data and fluorine source abundance
• On the stochastic nature of Galactic cosmic-ray sources
• Role of the radiative stage for cosmic ray acceleration in SNRs