Investigation of Cosmic Ray Acceleration and Propagation at Energies from MeV to the Energy Limit of Galactic Accelerators

Metadata Updated: February 28, 2019

The prime objective of the proposed work is to clarify the origin of Galactic cosmic rays through analysis and interpretation of experimental data on cosmic ray energy spectra and composition obtained in balloon, spacecraft and ground based experiments. This study will include modelling of cosmic ray acceleration and propagation in the Galaxy over a wide energy range from the lowest energies about a few MeV, where direct measurements were performed in the Voyager 1 mission, and up to energies >10^17 eV, where transition from Galactic to extragalactic components in the spectra observed at Earth most likely occurs. The proposed investigation is based on current theoretical concepts and the results of contemporary experiments in cosmic ray physics. Energy spectra of cosmic ray primary and secondary nuclei, shaped by cosmic ray diffusion in the interstellar medium, will be calculated and compared with spectra observed at Earth. Cosmic ray transport and acceleration in a self-consistent model of Galactic wind driven by cosmic ray pressure will be explored. The central topic of the proposed investigation is interpretation of anomalies in cosmic ray energy spectra, such as deviations from a plain power law and spectral hardening above ~230 GV. It also includes different slopes of proton and helium spectra, bending of cosmic ray spectra at energies below a few GeV/n, spectral and elemental peculiarities in the “knee” region, and transition to the extragalactic component in the observed cosmic rays. The study of cosmic accelerators supports the Science Mission Directorate's Goal for Astrophysics in NASA's 2010 Science Plan, “Discover how the universe works, explore how the universe began and evolved, and search for Earth-like planets.” It specifically addresses the Science Question, “How do matter, energy, space and time behave under the extraordinarily diverse conditions of the cosmos?”

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Public: This dataset is intended for public access and use. License: U.S. Government Work

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Metadata Created Date February 28, 2019
Metadata Updated Date February 28, 2019

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date February 28, 2019
Metadata Updated Date February 28, 2019
Publisher Space Technology Mission Directorate
Unique Identifier TECHPORT_94307
Maintainer Email
Public Access Level public
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 9a332cb1-1697-4e93-b719-c68ce9b91994
Harvest Source Id 39e4ad2a-47ca-4507-8258-852babd0fd99
Harvest Source Title NASA Data.json
Data First Published 2021-11-01
Homepage URL
Data Last Modified 2018-09-07
Program Code 026:027
Source Datajson Identifier True
Source Hash c091a3830188ca15de0f668ada6148d10f75339c
Source Schema Version 1.1

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