Speaker
Sushil Kumar Singh
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P4.2020.pdf
Calibration of a compact gamma-ray spectrometer for an energy range of
4-20 MeV
S. Singh1, A. Laso Garcia2, R. Versaci1, A. Ferrari2, M. Molodtsova2, L. Morejon1, R.
Schwengner2, D. Kumar,1 and T. Cowan2
1) ELI Beamlines, Institute of Physics of the ASCR, Dolni Brezany, Czech Republic
2) Institute for radiation physics, Helmholtz-Zentrum Dresden-Rossendorf, Germany
E-mail: Sushil.Singh@eli-beams.eu
With currently available high intensity lasers and the upcoming multi-PW facility at ELI-
Beamlines, copious amounts of gamma rays are expected to be generated in high intensity
laser-matter interaction experiments. Measurement of multi-MeV gamma-ray spectra in such
experiments provide direct indication of hot electrons generated inside the target. To
determine the spectrum of hot electrons and gamma rays, an appropriate spectrometer with
absolute calibration is essential. We report on the design of a compact gamma ray
spectrometer (GRS) of size 70 cm x 25 cm x 25 cm based on measuring forward Compton
scattered electrons by incoming gamma rays.
In this presentation, we describe the design parameters and calibration results of the GRS. The
calibration was performed using the bremsstrahlung facility gELBE [1] at the ELBE
accelerator of HZDR, Dresden. The calibration was conducted at different electron end point
energies, i.e. 11, 13, 15 and 18 MeV. Experimental spectra show systematic increase in the
maximum cut-off energy, temperature and flux. These results indicate that the spectrometer is
effective for an energy range of 4−20 MeV with 20-30% energy resolution. GRS provides an
opening angle of 23 mrad and experiments to measure bremsstrahlung spectrum from laser-
solid interaction are currently planned. The preliminary results from the experiment will also
be presented at the conference. Our work is supported by Czech Science Foundation project
18-09560S.
References
[1] R. Schwengner et al., Nucl. Instrum. Meth. A: Accelerators, 555.12, pp. 211-219, (2005).
