Accelerator beam test of the kinematic lightweight energy meter detector prototype for very high energy cosmic ray measurements in space

The idea of the KLEM (Kinematic Lightweight Energy Meter) detector is to directly measure the elemental energy spectra of very high-energy cosmic rays in space by determining the angular distribution of secondary particles produced in a target. The first test of the simple KLEM prototype was performed at the CERN SPS test-beam with 180 GeV pions. The results of the first test analysis confirm that, using the KLEM method, the energy of 180 GeV pions can be measured with a relative error of about 67%, which is very close to the results of the simulation (65 %).