Experimental study of the radiation emitted by 180-GeV/c electrons and positrons volume-reflected in a bent crystal

The radiation emitted by 180-GeV/c volume-reflected electrons and positrons impinging on a bent crystal has been measured by the H8RD22 Collaboration on the H8 beamline at the CERN SPS. A dedicated spectrometer has been developed to measure high-energy photon spectra (up to similar to 100 GeV) under volume reflection: photon and charged particle beams have been separated by a bending magnet and leptons were detected and tagged by microstrip silicon detectors and a Pb-scintillator sampling calorimeter. A comparison between the experimental and analytical data for the amorphous and volume-reflection cases is presented and the differences are discussed

Experimental study of the radiation emitted by 180-GeV/c electrons and positrons volume-reflected in a bent crystal

The radiation emitted by 180-GeV/c volume-reflected electrons and positrons impinging on a bent crystal has been measured by the H8RD22 Collaboration on the H8 beamline at the CERN SPS. A dedicated spectrometer has been developed to measure high-energy photon spectra (up to similar to 100 GeV) under volume reflection: photon and charged particle beams have been separated by a bending magnet and leptons were detected and tagged by microstrip silicon detectors and a Pb-scintillator sampling calorimeter. A comparison between the experimental and analytical data for the amorphous and volume-reflection cases is presented and the differences are discussed

Observation of multiple volume reflection by different planes in one bent silicon crystal for high-energy negative particles

Multiple volume reflection by different planes passing through the axis in a bent silicon crystal was observed for the first time for 150 GeV/c negative particles, pi(-) mesons, at one of the secondary beams of the CERN SPS. The beam of pi(-) mesons was deflected opposite to the crystal bend by an angle of about 48 mu rad, which is 4.6 times larger than in a single volume reflection by the (110) bent planes. The one-side deflection efficiency was about 65\%. Multiple volume reflection transforms to a single volume reflection when the orientation angle of the axis relative to the beam direction is increased. Copyright (c) EPLA, 201