Staff profile
Publication details for Prof Sir Arnold Wolfendale
Szabelski, J, Wibig, T & Wolfendale, AW (2002). Cosmic rays of the highest energies: the case for extragalactic heavynuclei. Astroparticle Physics 17(2): 125-131.- Publication type: Journal papers: academic
- ISSN/ISBN: 0927-6505
- Keywords: SPECTRUM; ARRAY
Author(s) from Durham
Abstract
An analysis has been made of the world's data on very large extensive
air showers with the object of deriving a 'best-fit' primary energy
spectrum.
It is reassuring that when the various, independently measured, spectra
are standardised, using as a datum the well-known 'dip' in the spectrum
at about 3 x 10(18) eV, and a correction for inferred 'noise', the
measurements are all consistent.
The best-fit spectrum bears out the well-known problem with the lack of
observation of a feature (a cut-off) due to interactions of the
particles, commonly assumed to be extra-galactic protons, with the
cosmic microwave background. However, we contend that a model involving
extragalactic nuclei [J. Phys. A 8 (1975) 1518; Astrophys. J. 205
(1976) 638; Astrophys. J. 512 (1999) 521] is satisfactory, although it
is premature to be too prescriptive, due to the shortage of
astronomical data. (C) 2002 Elsevier Science B.V. All rights reserved.