Change search
ReferencesLink to record
Permanent link

Direct link
PAMELA Measurements of Cosmic-Ray Proton and Helium Spectra
Show others and affiliations
2011 (English)In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 332, no 6025, 69-72 p.Article in journal (Refereed) Published
Abstract [en]

Protons and helium nuclei are the most abundant components of the cosmic radiation. Precise measurements of their fluxes are needed to understand the acceleration and subsequent propagation of cosmic rays in our Galaxy. We report precision measurements of the proton and helium spectra in the rigidity range 1 gigavolt to 1.2 teravolts performed by the satellite-borne experiment PAMELA (payload for antimatter matter exploration and light-nuclei astrophysics). We find that the spectral shapes of these two species are different and cannot be described well by a single power law. These data challenge the current paradigm of cosmic-ray acceleration in supernova remnants followed by diffusive propagation in the Galaxy. More complex processes of acceleration and propagation of cosmic rays are required to explain the spectral structures observed in our data.

Place, publisher, year, edition, pages
2011. Vol. 332, no 6025, 69-72 p.
National Category
Astronomy, Astrophysics and Cosmology
URN: urn:nbn:se:su:diva-80712DOI: 10.1126/science.1199172ISI: 000289000000038OAI: diva2:557345


Available from: 2012-09-27 Created: 2012-09-27 Last updated: 2012-09-27Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text
By organisation
The Oskar Klein Centre for Cosmo Particle Physics (OKC)
In the same journal
Astronomy, Astrophysics and Cosmology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 26 hits
ReferencesLink to record
Permanent link

Direct link