Probability of inelastic nuclear interactions of high-energy protons in a bent crystal

A model for the interaction of high-energy particles in straight and bent crystals implemented in Geant4

“…Experiments studying the efficiency of channeling vs. incoming angle [29], the rate of inelastic nuclear interaction under channeling [14], and the channeling efficiency dependence on radius of curvature for bent crystals [76], were simulated for positive particles. For negative particles, simulations of the dechanneling length for high energy pions [58] was performed.…”

“…For measurement of the rate of inelastic nuclear interaction, two scintillators were added to reproduce the experimental setup of Ref. [14]. To speed up simulation, vol- …”

“…Radiation emission due to curved trajectories in bent crystals has been seen to enhance photon production through bremsstrahlung, channeling radiation, parametric X-ray radiation, undulators [7][8][9][10][11] and recently through volume reflection and multiple volume reflection [12,13]. The inelastic nuclear interaction rate is known to be modified by channeling and volume reflection [14].…”

“…Indeed, with recent optimizations in manufacturing techniques [26,27] and crystal holders [28], bent crystals have been produced with record deflection efficiencies [29]. As a consequence of this and the reduction of the nuclear interaction rate for channeled positive particles [14], the use of collimation systems based on bent crystals has proven to lower beam losses throughout the SPS synchrotron for protons [30] and for Pb ions [31,32].…”

“…Thanks to the large amount of data [14,29,[45][46][47][48][49][50][51][52][53][54][55][56][57][58][59] with track reconstruction resolutions of <10 µrad, [46] Monte Carlo codes based on the experimental cross sections of orientational phenomena were developed [57,60]. With this model, very high computational throughput is achieved but the scaling of dechanneling models is inaccurate due to the lack of a dedicated campaign of measurement.…”