A Fourier analysis of the magnitudes and timing of the Phanerozoic mass extinctions (MEs) demonstrates that many of the periodicities claimed in other analyses are not statistically significant. ...Moreover we show that the periodicities associated with oscillations of the Solar System about the galactic plane are too irregular to give narrow peaks in the Fourier periodograms. This leads us to conclude that, apart from possibly a small number of major events, astronomical causes for MEs can largely be ruled out.
Periodicity in extinction rates Erlykin, Anatoly D.; Harper, David A. T.; Sloan, Terry ...
Palaeontology,
January 2018, 2018-01-00, 20180101, Letnik:
61, Številka:
1
Journal Article
DO WE SEE THE ‘IRON PEAK’? Erlykin, Anatoly D.; Wolfendale, Arnold W.
Acta polytechnica (Prague, Czech Republic : 1992),
01/2013, Letnik:
53, Številka:
A
Journal Article
Recenzirano
Odprti dostop
Recent measurements of the cosmic ray (CR) energy spectrum in the PeV region and above have confirmed the remarkable sharpness of the knee and revealed another structure at about 70PeV which we call ...the ‘Iron Peak’. The position and the shape of this structure lead us to associate its likely origin with the same single source responsible for the the knee. We have analysed the shape of the single source spectrum and concluded that its mass composition is rather similar to that for the bulk of CR in the TeV ÷ PeV region. Since it is generally accepted that these CR originate mainly in supernova explosions, this gives an additional argument in favour of our single source being a supernova remnant.
Ultra high energy cosmic rays Wibig, Tadeusz; Wolfendale, Arnold W
Journal of physics. G, Nuclear and particle physics,
09/2007, Letnik:
34, Številka:
9
Journal Article
George Rochester was a Tynesider through and through, and his family on both sides had lived in the area for 200 years. University
appointments took him away, but when in 1955 he had the opportunity ...to return to his roots—the Chair of Physics at Durham—he
accepted with alacrity. He stayed in this city, so close to the Tyne, for the rest of his life.
► Gamma-ray astronomy gives evidence of the galactic origin of CR at GeV energies. ► CR energy spectrum indicates the non-uniform space–time distribution of CR sources. ► Galactic supernova remnants ...(SNRs) are the most likely source of CR up to PeV energies. ► High density of SNR in the inner galaxy creates flatter energy spectrum than locally.
The case is made for most cosmic rays having come from galactic sources. ‘Structure’, i.e. a lack of smoothness in the energy spectrum, is apparent, strengthening the view that most cosmic rays come from discrete sources, supernova remnants being most likely.
Peter Fowler was a distinguished physicist to whom physics was sheer enjoyment and this enjoyment brought delight to those
around him. His students, associates and friends were inspired by his ...infectious enthusiasm, his agility at mental arithmetical
calculation and his distinctive laugh. The fun of discovery, of seeking understanding of what was hidden, characterized all
his work and indeed his approach to life generally.
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