Gamma-Ray Emission from the Shell of Supernova Remnant W44 Revealed by the Fermi LAT
2010 (English)In: Science, ISSN 0036-8075, Vol. 327, no 5969, 1103-1106 p.Article in journal (Refereed) Published
Recent observations of supernova remnants (SNRs) hint that they accelerate cosmic rays to energies close to similar to 10(15) electron volts. However, the nature of the particles that produce the emission remains ambiguous. We report observations of SNR W44 with the Fermi Large Area Telescope at energies between 2 x 10(8) electron volts and 3 x 10(11) electron volts. The detection of a source with a morphology corresponding to the SNR shell implies that the emission is produced by particles accelerated there. The gamma-ray spectrum is well modeled with emission from protons and nuclei. Its steepening above similar to 10(9) electron volts provides a probe with which to study how particle acceleration responds to environmental effects such as shock propagation in dense clouds and how accelerated particles are released into interstellar space.
Place, publisher, year, edition, pages
2010. Vol. 327, no 5969, 1103-1106 p.
shocked molecular gas, pulsar wind nebula, very-high-energy, particle-acceleration, streaming instability, wave dissipation, rx, j1713.7-3946, area telescope, galactic plane, cosmic-rays
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:kth:diva-19250DOI: 10.1126/science.1182787ISI: 000274901100028ScopusID: 2-s2.0-77649202347OAI: oai:DiVA.org:kth-19250DiVA: diva2:337297
FunderKnut and Alice Wallenberg FoundationSwedish Research Council
QC 201005252010-08-052010-08-052011-01-20Bibliographically approved