Study of imaging plate detector sensitivity to 5-18 MeV electrons

Abstract

Imaging plates (IPs) are commonly used as passive detectors in laser-plasma experiments. We calibrated at the ELSA electron beam facility (CEA DIF) the five different available types of IPs (namely, MS-SR-TR-MP-ND) to electrons from 5 to 18 MeV. In the context of diagnostic development for the PETawatt Aquitaine Laser (PETAL), we investigated the use of stacks of IP in order to increase the detection efficiency and get detection response independent from the neighboring materials such as X-ray shielding and detector supports. We also measured fading functions in the time range from a few minutes up to a few days. Finally, our results are systematically compared to GEANT4 simulations in order to provide a complete study of the IP response to electrons over the energy range relevant for PETAL experiments.

Calibration of imaging plates to electrons between 40 and 180 MeV

“…Results for higher electron energies are presented for MS IP (above 120 MeV), for which there is sufficient signal for our analysis. Our response functions of MS, SR, and TR are comparable with our previous work 13 with Tanaka et al 9 and Nakanii et al 10 The PSL/e − values for each type of IP (see Fig. 7) are almost constant as the electron energy increases.…”

“…The uncertainty on the fading time dependence is 7%. 13 Therefore, in our case the uncertainty coming from the fading correction is 7% of, respectively, 2%, 5%, and 15% and hence negligible with respect to the other uncertainties in the calibration.…”

“…ions. As it is observed in simulations and experiments, 13 backscattering from material behind the IPs might lead to the increase of the signal depending on the particle type and energy as well as on the material itself. Therefore the response of the detectors must be made independent of the IP position inside SEPAGE.…”

“…To our knowledge, there is no available data on the response function of Fuji MS and TR IPs for electrons with energy above 20 MeV, where published data of Fuji SR IP [9][10][11][12][13] are also scarce. In 2005, Tanaka et al 9 measured the response of SR IP with 11.5, 30, and 100 MeV using a BAS-1800 scanner.…”

“…Their study permitted to estimate the responses of IPs to other types of particles such as photons, electrons, and 4 He. 12 In our experiment on ELSA at Bruyères-le-Châtel, 13 we used 5, 10, and 18 MeV mono-energetic electrons. This work shows basic agreement with the literature.…”