Diffractive effects in spin-flip pp amplitudes and predictions for relativistic energies

We analyze the diffractive (Pomeron) contribution to pp spin-flip amplitude and discuss the possible scenarios for energies available at the Relativistic Heavy-Ion Collider (RHIC). In particular, we show that RHIC data will be instrumental in assessing the real contribution of diffraction to spin amplitudes.Comment: 11 pages, 12 Encapsulated PostScript files, LaTeX2e use

Multiple muon events observed underground

Observations are reported on events involving multiple penetrating particles recorded in a scintillator-neon flash tube telescope, at a depth of 1500 hg/cm2 in the Kolar Gold Mines. From these, it is shown that: (1) the cross-section for nuclear interaction of muons of average energy ~200 GeV is ~6 × 10-30 cm2/nucleon; (2) the decoherence curve for events involving two parallel muons is uniform over the range of distances from 0 to 2 metres; and (3) the angular distribution of double-parallel muons closely resembles that of single muons, implying that these two types of events are probably produced in the atmosphere in a similar manner

The Kolar Gold Fields Neutrino Experimen. I. The Interactions of Cosmic Ray Neutrinos

Final results are presented of an experiment to study the interactions of cosmic ray neutrinos deep underground, at a depth of 7.6 ×105g cm-2 (standard rock). Clear examples have been recorded of neutrino-induced muons, including cases of upward moving particles and neutrino interactions within the detector assembly itself. The observed rate of events is compared with expectation and conclusions are made about the variation of the inelastic cross-section with energy and the lower limit to the mass of the intermediate boson. An examination has also been made of the celestial coordinates of the detected neutrinos and details are presented

V. Studies of Cosmic Ray Neutrino Interactions in the Kolar Gold Field Experiment

Results are presented of an experiment to study the penetrating particles in the cosmic radiation deep underground, at a depth of 7500 m.w.e. (standard rock). The events recorded are attributable, in the main, to muons produced either in the atmosphere or by the interactions of neutrinos in the surrounding rock. The muons have been studied in some detail and it appears that the mean energy of the neutrino induced muons (probably less than about 30 GeV) is low compared with that of the muons of atmospheric origin. The significance of the celestial coordinates of the muons and the measured rate of neutrino-induced muons is discussed and the future experimental programme is indicated

The Kolar Gold Fields neutrino project.

In the underground laboratory at a depth of 7 600 ft in the Kolar Gold Mines, South India, five telescopes have been in operation for a study of the cosmic radiation which penetrates to such depths. In an exposure of 677 400 m2 sr h (for isotropic radiation) 46 events have been recorded. In seven events the particle trajectory has a projected zenith angle larger than 50°; these are interpreted as due to muons produced by neutrino interactions in the surrounding rock. From this the rate of neutrino-induced events is estimated to be about 3.1 × 10−13/cm2 s sr.The bulk of events with projected zenith angles less than 40° are interpreted as due to atmospheric muons, from considerations of the expected intensity and angular distribution. In between the above-mentioned two groups, there are 10 events in the zenith angle interval 40°–50° compared with an expected number of events of about two. The difference between the observed and expected rates in this angular interval is discussed.Recently, two new solid-iron magnet spectrographs have been installed at the same level, for measuring the momentum and sign of charge of the muons traversing the detector system. Each spectrograph has a maximum detectable momentum of 20 GeV/c and a collecting power of about 35 m2 sr for isotropic radiation

Muon intensities and angular distributions deep underground

Recent measurements of the intensity of muons below 3000 m.w.e. (metres water equivalent) underground have been combined to give an estimate of the depth-intensity relation and the angular distribution for atmospheric muons down to a maximum depth of approximately 9000 m.w.e. It is found that the vertical intensity can be represented by the expression I(0, h) = 9.8 × 10-7 exp(-h/λ)cm-2sec-1sterad-1 where h is the depth in m.w.e. and λ = 810 ± 50 m.w.e. The corresponding angular distribution at vertical depth h is given by I(θ, h) = I(0, h) secθ exp{-(h/λ)(secθ - 1)} where θ is the zenith angle. The implication of the above angular distribution for the estimate of neutrino fluxes in deep underground cosmic-ray experiments is discussed