High energy muons in large extensive air showers

A magnet spectrograph in the centre of a large array of diff-used-light water Čerenkev detectors has been used to measure the momentum spectrum and lateral distribution of muons in large extensive air showers. The data cover the ranges: 1-100 GeV/c in muon momentum, 10-700 metres in core distance, and 10(^5)-10(^8) particles in shower size. The spectra are presented in the form of integral and differential densities as functions of muon momentum and EAS core distance. Details are given of the construction of the spectrograph and EAS arrays, the collection and treatment of the data, and the derivation of the momentum spectra and the analysis of the results. Experimental results are also presented on the charge ratio of EAS muons, and an interpretation is offered for the bursts, observed in the visual detectors, which are produced in the spectrograph iron. Wherever possible, comparison is made between the results of the experiment and the observations of other workers. Previous theoretical models of EAS muori production have been critically examined and it is shown that the assumptions on which they are based are not valid for all EAS muons. In particular, the density of muons possessing large momenta far from the shower core is sensitive to the assumptions made about the first interaction of the primary cosmic ray. A careful analysis of the problem shows that such muons provide a means of estimating the mass of primary cosmic rays in the EAS energy region

The 1000 GeV gamma rays from ms pulsars

The detection of 1000 GeV gamma-rays with the characteristic 6.1 ms periodicity of the radio pulsar PSR 1953 +29 is reported. This result, significant at the 5.4 beta level, provides the first direct evidence for the association of the 6 ms radio pulsar PSR1953+29 with the gamma-ray source 2CG065+0. Extensive observations of the 1.5 ms pulsar PSR 1937 are also reported

The 1000 GeV gamma ray emission from radio pulsars

Radio pulsars have concentrated on long observations of the Crab pulsar and showed that it emits short intense bursts and a persistent weak periodic flux at gamma-ray energies 1000 GeV. It was shown that the light curve of the persistent emission was dominated by a single peak, coincident with the position of the radio and low energy gamma-ray main pulse. The results of a more detailed analysis of the structure of this main pulse are reported following an appraisal of the timing system. It is shown that at energies 1000 GeV the duration of the main pulse is not greater than 0.4 ms, which is less than that seen at all frequencies other than radio. Flux limits for the emission of 1000 GeV gamma-rays by seven other radio pulsars are reporte

1000 GeV gamma rays from Cygnus X-3: An update

Measurements of 1000 GeV gamma-rays from Cygnus X-3 made with the University of Durham facility at Dugway, Utah in 1981/82 are reviewed. The light curve of the 4.8 hour modulated emission is updated and shows evidence significant at the 4.4 sigma level for strong emission (9% of the cosmic ray rate) at phase 0.625 and less significant (1.4 sigma level) indications of weaker emission (3% of the cosmic ray rate) at phase 0.125. The effect constituting the excess on the few nights showing the strongest emission appears to arise from the smallest Cerenkov light signals suggesting a steep gamma-ray spectrum. The 1982 data have been searched unsuccessfully for evidence of emission at phase 0.2, in coincidence with the results from the ultra-high energy (extensive Air Showers (EAS) measurements in 1979-1982. A systematic investigation of a long term variation in the strength of the peak of the 4.8 hr modulated 1000 GeV gamma-ray emission has been made. We find that in addition to the approximately 34 d variation reported by us previously, a stronger effect exists at around 19d