Fitting B/C cosmic-ray data in the AMS-02 era: A cookbook

Abstract

AMS-02 on the International Space Station has been releasing data of unprecedented accuracy. This poses new challenges for their interpretation. We refine the methodology to get a statistically sound determination of the cosmic-ray propagation parameters. We inspect the numerical precision of the model calculation, nuclear cross-section uncertainties, and energy correlations in data systematic errors. We used the 1D diffusion model in USINE. Our ${\chi }^2$ analysis includes a covariance matrix of errors for AMS-02 systematics and nuisance parameters to account for cross-section uncertainties. Mock data were used to validate some of our choices. We show that any mis-modelling of nuclear cross-section values or the energy correlation length of the covariance matrix of errors biases the analysis. It also makes good models (${\chi }_{\min }^2/\mathrm{dof}\approx 1$) appear as excluded (${\chi }_{\min }^2/\mathrm{dof}\gg 1$). We provide a framework to mitigate these effects (AMS-02 data are interpreted in a companion paper). New production cross-section data and the publication by the AMS-02 collaboration of a covariance matrix of errors for each data set would be an important step towards an unbiased view of cosmic-ray propagation in the Galaxy.

arXiv comment24 pages, 23 figures, 3 tables: affiliations corrected

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Cited by in corpus (33)

• 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
• Dark matter or correlated errors: Systematics of the AMS-02 antiproton excess
• AMS-02 antiprotons' consistency with a secondary astrophysical origin
• USINE: semi-analytical models for Galactic cosmic-ray propagation
• Implications of Lithium to Oxygen AMS-02 spectra on our understanding of cosmic-ray diffusion
• Cosmic-ray database update: ultra-high energy, ultra-heavy, and anti-nuclei cosmic-ray data (CRDB v4.0)
• Markov chain Monte Carlo analyses of the flux ratios of B, Be and Li with the DRAGON2 code
• New minimal, median, and maximal propagation models for dark matter searches with Galactic cosmic rays
• Secondary cosmic-ray nucleus spectra disfavor particle transport in the Galaxy without reacceleration
• A simple determination of the halo size $L$ from ${}^{10}$Be/${}^9$Be data
• Time dependent solar modulation of cosmic rays from solar minimum to solar maximum
• Cosmic-ray antiprotons in the AMS-02 era: A sensitive probe of dark matter
• The importance of Fe fragmentation for LiBeB analyses: Is a Li primary source needed to explain AMS-02 data?
• Dark Matter in X-rays: Revised XMM-Newton Limits and New Constraints from eROSITA
• The rigidity dependence of galactic cosmic-ray fluxes and its connection with the diffusion coefficient
• Origin of hardening in spectra of cosmic ray nuclei at a few hundred GeV using AMS-02 data
• Weighing the Local Interstellar Medium using Gamma Rays and Dust
• In-flight positron annihilation as a probe of feebly interacting particles
• Hybrid origins of the cosmic-ray nuclei spectral hardening at a few hundred GV
• Injection spectra of different species of cosmic rays from AMS-02, ACE-CRIS and Voyager-1
• AMS-02 antiprotons and dark matter: Trimmed hints and robust bounds
• Transport parameters from AMS-02 F/Si data and fluorine source abundance
• Testing the consistency of proapgation between light and heavy cosmic ray nuclei
• Reanalysis of the Systematic Uncertainties in Cosmic-Ray Antiproton Flux
• Reexamine the dark matter scenario accounting for the positron excess in a new cosmic ray propagation model
• $\overline{\text{D}}$arkRayNet: Emulation of cosmic-ray antideuteron fluxes from dark matter
• The GALPROP Cosmic-ray Propagation and Non-thermal Emissions Framework: Release v57
• Quantitative study of the hardening in the Alpha Magnetic Spectrometer nuclei spectra at a few hundred GV
• Spectra of He isotopes and the ${}^3$He/${}^4$He ratio
• Revisiting electron-capture decay for Galactic cosmic-ray data
• Analyzing Cosmic Ray Spectral Features: A Numerical Investigation
• Deciphering the Electron Spectral Hardening in AMS-02