Structure in the cosmic ray spectrum: an update

An update is given of the evidence from extensive air showers relating to our claim that there is `structure' in the energy spectrum of high-energy cosmic rays. The structure is explained, in our model, in terms of there having been a recent nearby supernova, the remnant of which has accelerated cosmic ray nuclei, with rather sharp energy cut-offs at ~ 3×10<sup>6</sup> GeV for oxygen nuclei and ~ 1×10<sup>7</sup> GeV for iron nuclei. The addition of the later data on the shower size spectra which amounts to a 250% increase and includes that of Cherenkov radiation, hadrons and muons, is considered by us to enhance the probability of our model being correct, although the case is still not `watertight'.