B. N. Kalinin

The investigation of a model of an EM calorimeter on NaBi (WO4)2 crystals

We have constructed a mock-up model consisting of nine elements to evaluate the space and energy resolution of the NaBi(WO4)2 crystal electromagnetic calorimeter. The characteristics of the mock-up model have been studied with a 700 MeV electron beam. It is shown that with cell dimensions of about 2.4 cm one can achieve an accuracy of < 4 mm in measuring the coordinates. The investigations have shown that the calorimeter has fast operation, satisfactory energy resolution and good space resolution characteristics.

Study of temperature dependence of light yield from NaBi(WO4)2 crystals

Abstract The scintillation time structure and the temperature dependence of the light yield from NaBi(WO 4 ) 2 crystals bombarded by 500 MeV electrons have been measured experimentally. These crystals showed a tendency to exhibit scintillator properties when the temperature of the samples was decreased. The light yield increased by more than an order of magnitude with the temperature falling from the room level to that of liquid nitrogen. The scintillation time structure was of a complex pattern, and a slow luminescent component (τ = 30 ns) was present in the spectrum.

Experimental investigation of coherent bremsstrahlung in a mosaic pyrolytic graphite crystal

Abstract Orientation dependences (OD) have been measured for gamma radiation from 890 MeV elecrons in a one-dimensional periodic structure formed by mosaic pyrolytic graphite. Comparison between the experimental ODs and the calculated ones was done. The mosaic structure of the target is shown to be responsible for suppression of hard radiation yield in forward direction due to electron scattering in the lattice plane potential of mosaic graphite.