[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] Theoretical calculations predict a small fractional difference in energy loss for μ⁺ and μ^- of the order of 0.15% at high energies. This is predominantly due to a z³ term in an extended ionization dE/dX relation, in analogy to the Barkas effect at low energies around the Bethe-Bloch maximum. The atmospheric muon energy spectrum is steeply falling off with approximately E^-3.7 and thus the small difference in dE/dX between μ⁺ and μ^- at high energies results in an amplified charge asymmetry of about 0.6% a few thousand meters water equivalent deep underground.

[en] MINOS is the first large magnetic detector deep underground and is the first to measure the muon charge ratio with high statistics in the region near 1 TeV.[1] An approximate formula for the muon charge ratio can be expressed in terms of η_π = 115 GeV, η_K = 850 GeV and E_μ^surfaceThe implications for K production in the atmosphere will be discussed

No abstract available

[en] Sea level muon charge ratio has been estimated from the CERN proton accelerator results on the nucleon-nucleus interaction after Stevenson. The primary cosmic ray spectrum of Olejniczak, Wdowczyk and Wolfendale has been used as the nucleon source. The structure function for p-Be interactions given by Trilling has been used in the calculations for charged pion and kaon productions

[en] The magnetized MINOS near detector can accurately determine the charge sign of atmospheric muons, this facilitates a measurement of the atmospheric muon charge ratio. To reduce the systematic error associated with geometric bias and acceptance we have combined equal periods of data obtained with opposite magnetic field polarities. We report a charge ratio of 1.2666 ± 0.0015(stat.)_-0.0088^+0.0096(syst.) at a mean E_μ,0#sup cos#(θ) = 63 GeV. This measurement is consistent with the world average but significantly lower than the earlier observation at the MINOS far detector. This increase is shown to be consistent with the hypothesis that a greater fraction of the observed muons arise from kaon decay within the cosmic ray shower.

[en] The μ⁺/μ^- ratio observed in high energy cosmic rays has been a riddle since first estimates based on secondary pion decay gave too high a value. Taking into account inclusive pion distributions measured at ISR energy and the α content of the primary flux, which is now well known, one obtains a ratio which is in reasonable agreement with experimental observation

[en] We calculate the intensities and angular distributions of positive and negative muons produced by atmospheric neutrinos. We comment on some sources of uncertainty in the charge ratio. We also draw attention to a potentially interesting signature of neutrino oscillations in the muon charge ratio, and we discuss the prospects for its observation (which are not quite within the reach of currently planned magnetized detectors)

[en] The ALEPH detector at LEP has been used to measure the momentum spectrum and charge ratio of vertical cosmic ray muons underground. The sea-level cosmic ray muon spectrum for momenta up to 2.5 TeV/c has been obtained by correcting for the overburden of 320 meter water equivalent (mwe). The results are compared with Monte Carlo models for air shower development in the atmosphere. From the analysis of the spectrum the total flux and the spectral index of the cosmic ray primaries is inferred. The charge ratio suggests a dominantly light composition of cosmic ray primaries with energies up to 10¹⁵ eV.

[en] The magnetized MINOS Near Detector, at a depth of 225 mwe, is used to measure the atmospheric muon charge ratio. The ratio of observed positive to negative atmospheric muon rates, using 301 days of data, is measured to be 1.266±0.001(stat)_-0.014^+0.015(syst). This measurement is consistent with previous results from other shallow underground detectors and is 0.108±0.019(stat+syst) lower than the measurement at the functionally identical MINOS Far Detector at a depth of 2070 mwe. This increase in charge ratio as a function of depth is consistent with an increase in the fraction of muons arising from kaon decay for increasing muon surface energies.