Measurement of the flux of charged hadrons at sea level between 250 and 10,000 GeV

The flux of charged hadrons has been measured at sea level with an iron calorimeter of depth 960 g cm-2; the geometric factor was about 0.7 m2 sr. The total running time was 1.6 x 106 s. The measured values of the differential vertical flux of charged hadrons unaccompanied over 3.3 m2 in the range 250 < E < 1200 GeV and of all hadrons for 300 < E < 1700 GeV are given. An upper limit to the flux of all hadrons has been obtained in the energy range 500 < E < 10,000 GeV. It does not support the observation of a 'step' in the spectrum at about 3000 GeV. (author)