Measurements of high-energy neutron and proton fluxes on-board “Mir-Spectr” orbital complex

Abstract

The measurements of high-energy neutron (with energies∼ 30–300 MeV) and proton (with energies ∼ 1–200 MeV) fluxes are being conducted on-board “Mir-Spectr” orbital complex. Neutrons are detected by the undirected (FOV ∼ 4π sr) scintillator spectrometer, consisting of 4 identical CsI(Tl) detector units (the effective area for neutrons ∼ 30 cm 2). The gamma-quanta, which can be also detected by this instrument, are separated from neutrons by the analysis of the scintillator output pulse shape. To exclude registration of charged particles an anticoincidence plastic scintillator shield is realized in each detector unit. The proton fluxes are measured by the telescope based on 3 semiconductor detectors with small geometry factor (∼1 cm 2×sr). As the first result of the experiment the upper limit of the integral flux of local and albedo neutrons in the equatorial region (L<1.1) was estimated. The results of this measurements can be useful for the radiation security. Also, the neutrons of solar flares can be detected in this experiment.