Inference of the Local Interstellar Spectra of Cosmic-Ray Nuclei Z ⩽ 28 with the GalProp-HelMod Framework

Area of Science:

• Astrophysics
• Cosmic Ray Physics
• Planetary Science

Background:

• Galactic cosmic rays (CRs) composition and spectra are crucial for understanding high-energy astrophysical processes.
• AMS-02 provides high-quality CR spectra, but data for heavier and low-abundance nuclei are forthcoming.
• Previous data, like HEAO-3-C2, may contain undocumented systematic errors, complicating their use.

Purpose of the Study:

• To address the lack of AMS-02 data for heavier cosmic ray nuclei.
• To validate and utilize a fraction of HEAO-3-C2 data by comparing it with AMS-02 measurements.
• To predict the local interstellar spectra (LIS) for nuclei not yet measured by AMS-02.

Main Methods:

• Cross-validation of HEAO-3-C2 data against available AMS-02 measurements.
• Integration of validated HEAO-3-C2 data with Voyager 1 and ACE-CRIS datasets.
• Utilizing the GalProp-HelMod framework for updated LIS calculations.

Main Results:

• A subset of HEAO-3-C2 data shows good agreement with AMS-02 measurements.
• Predictions for LIS of unreleased nuclei by AMS-02 were generated.
• Updated LIS from Hydrogen to Nickel (1H-28Ni) across 8-9 orders of magnitude in energy (1 MeV to ~500 TeV).

Conclusions:

• A hybrid approach using multiple datasets can successfully extend cosmic ray spectra predictions.
• The GalProp-HelMod framework is a reliable tool for deriving comprehensive LIS.
• This work provides essential data for interpreting astrophysical observations and searching for new phenomena.