[en] Information about the energy spectrum of sea level muons at high energies beyond magnetic spectrographs can be obtained from underground intensity measurements if the fluctuations problems are solved. The correction factor R for the range fluctuations of high energy muons were calculated by the analytical method of Zatsepin, where the most probable energy loss parameters are used. It is shown that by using the R at great depth together with the slope, lambda, of the vertical depth-intensity (D-I) curve in the form of exp(-t/lambda), the spectral index, gamma, in the power law energy spectrum of muons at sea level can be obtained

[en] Focusing on high energy neutrinos ( or = 1 TeV), a new calculation of atmospheric neutrino intensities was carried out taking into account EMC effects observed in p-A collisions at accelerators, recent measurement of primary cosmic ray spectrum, and results of cosmic ray muon spectrum and charge ratio. Other features of the present calculation are (1) taking into account kinematics of three body decays of kaons and charm particles in diffusion equations and (2) taking into account energy dependence of kaon production

No abstract available

[en] Using a 600 MeV electron beam from the INS electron synchrotron, characteristics of a gas proportional chamber were studied by observing showers produced in heavy materials, such as lead and iron. From the results, we discuss the application of measurements with the chamber to shower transition curves at higher energies. (orig.)

[en] Hadronic cascade showers originating from inelastic interactions of cosmic ray muons with iron nuclei have been observed in a calorimeter located between two magnetic spectrometers. The separation of those events from the electromagnetic showers has been successfully done in the ranges of the transferred energy ν > approximately 50 GeV and its ratio to muon energy ν/E > approximately 0.1, by utilizing the difference of their longitudinal cascade developments. The comparison of the obtained μ-Fe cross section with available μ-, e- and γ-proton data as well as μ-, e- and γ-nucleus data indicates that; 1) At ν approximately 100 GeV, the virtual photon cross section on iron nucleus is almost the same as the real photon one, at least Q² < approximately 0.1 GeV²/c², and is about 70% of the cross section on proton times the atomic mass number if iron, i.e. the shadowing effect is clearly seen. 2) Up to TeV region, this virtual photon cross section on iron does not increase significantly, contrary to the tendency of the real photon cross section on proton around 100 GeV. This suggests most likely that the shadowing still increases with energy at such high energies. (author)

[en] The linearity to the number of shower particles observed by a gas proportional chamber was checked by comparison with scintillation counter observation. Linear response up to about 1000 shower particles was obtained. However, the number of shower particles observed by the proportional chamber is approximately a factor 2 higher than that by the scintillation counter, and this difference may be attributed to the different threshold energy between the two counters. (orig.)

[en] By using a quark parton model combined with parton recombination model in high energy collisions, the μ⁺/μ^- ratio at sea level for various zenith angles are calculated. It is shown that the inclusion of gluon effect leads to a good agreement with the recent experimental data

[en] For measurements of the cosmic-ray muon spectrum at energies above 100 TeV and for observations of high-energy astronomical neutrinos a big detector is necessary. In both cases, information on the muon energy plays an important role. The method for estimating the muon energy from the energy loss should yield accurate values with a big detector. To evaluate the method we measured the muon energy-loss distribution in the MUTRON detector and applied the results to a big detector proposed for deployment in the ocean. When estimating the muon energy we divided the muon track into several segments and discarded the segment with the maximum energy loss. If a detector with a volume of (500 m)³ is constructed in the ocean using strings of detectors with 50-m spacing between adjacent strings, and 10-m spacing between detectors on a string, muon energies could be measured with a relative error of about 30%. For muons produced by the charged-current interaction (ν_μ+N→μ+X), the neutrino direction can be determined with an error less than 1 degree for muon energies above 1 TeV

[en] The charge ratio of cosmic-ray muons at sea-level is calculated by using recent experimental results on cosmic-ray primaries and hadron (lepton)-nucleus collisions. It is shown that the charge ratio agrees with the observed ratio up to 10 TeV if a fraction 0.05 of quark-gluon plasma state in nucleus-nucleus collisions is included

[en] When the total proteins from Xenopus laevis 60 S ribosomal subunits (TP60) were ³H-labeled in vitro and injected back into X. laevis oocytes, most ³H-TP60 are integrated into the cytoplasmic 60 S subunits via the nucleus during 16 h of incubation. In the oocytes whose rRNA synthesis is inhibited, ³H-TP60 are rapidly degraded with a half-life of 2-3 h. This degradation ceased as soon as rRNA synthesis was resumed, suggesting that ribosomal proteins unassociated with nascent rRNA are unstable in the oocytes. The degradation of ³H-TP60 in the absence of RNA synthesis was inhibited by iodoacetamide, a cysteine protease inhibitor, resulting in the accumulation of ³H-TP60 in the nucleus reaching about a threefold concentration in the cytoplasm. Considering the results with enucleated oocytes, we suggest that the X. laevis nucleus has a limited capacity to accumulate ribosomal proteins in an active manner but that those ribosomal proteins accumulated in excess over rRNA synthesis are degraded by a cysteine protease in the nucleus. By contrast, ribosomal proteins from Escherichia coli only equilibrate between the nucleus and the cytoplasm and are degraded by serine protease(s) in the cytoplasm without being integrated in the form of ribosomes in the nucleus