A new measurement of the momentum spectra of both positive and negative muons as a function of atmospheric depth was made by the balloon-borne experiment CAPRICE94. The data were collected during ground runs in Lynn Lake on 19 and 20 July 1994 and during the balloon flight on 8 and 9 August 1994. We present results that cover the momentum intervals 0.3-40 GeV/c for μ - and 0.3-2 GeV/c for μ +, for atmospheric depths from 3.3 to 1000 g/cm2, respectively. Good agreement is found with previous measurements for high momenta, while at momenta below 1 GeV/c we find latitude dependent geomagnetic effects. These measurements are important cross-checks for the simulations carried out to calculate the atmospheric neutrino fluxes and to understand the observed atmospheric neutrino anomaly.
Physical Review D
- Pub Date:
- August 2000
- Neutrino mass and mixing;
- High Energy Physics - Experiment
- 28 pages, 13 Postscript figures, uses revtex.sty, to appear in Phys. Rev. D