Low-energyp,p¯, anddvertical intensities at mountain altitude

A cosmic-ray magnetic-particle spectrometer utilizing wire spark chambers and a superconducting magnet for momentum determination and scintillators for charge and velocity determination has been operated at an atmospheric depth of 747 g/${\mathrm{cm}}^2$. Twenty weeks of data were taken and the proton (p) energy spectrum in the momentum range of 0.6 to 2.4 GeV/c has been determined. Antiproton (p¯) events were observed and a p¯/p ratio of ${1.5}_{\mathrm{-}0.95}^{+1.85\mathrm{}}$ at a momentum of 1.05 GeV/c was measured. Deuteron intensities and α-particle upper limits for this energy region are also presented.