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With a prototype of a large hadron calorimeter, vertical cosmic-ray hadrons were recorded and the all-hadron flux was measured in the range from 10 GeV to 10 TeV. By means of a layer of scintillation counters, the neutral and charged components were identified and the ratio of neutral to charged hadrons could be extracted. From this ratio the charged-pion content is inferred using reasonable assumptions on the neutron-to-proton ratio. At the lower-energy end the data are compared firstly with existing results and secondly with theoretical calculations and Monte Carlo simulations.

Abstract.A search for potential point sources of very high energy gamma rays has been carried out on the data taken simultaneously by the HEGRA AIROBICC and Scintillator arrays from August 1994 to March 2000. The list of sought sources includes supernova remnants, pulsars, AGNs and binary systems. The energy threshold is around 15 TeV. For the Crab Nebula, a modest excess of 2.5 standard deviations above the cosmic ray background has been observed. Flux upper limits (at 90% c.l.) of around 1.3 times the flux of the Crab Nebula are obtained, in average, for the candidate sources. A different search procedure has been used for an all-sky search which yields absolute flux upper limits between 4 and 9 crabs depending on declination, in the band from δ = 0 to δ = 60 • .

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