CALOR 2018

Fast Neutron Induced Radiation Damage in Fast Inorganic Scintillators

24 May 2018, 08:55

20m

Ballroom, Erb Memorial Union (University of Oregon)

Session 10

Speaker

Liyuan Zhang (California Institute of Technology (US))

Description

One crucial issue for applications of scintillation crystals in HEP calorimeters is radiation damage in severe radiation environment, such as the HL-LHC. While radiation damage induced by ionization dose is well understood, investigations are still on going to understand radiation damage caused by hadrons, including both charged hadrons and neutrons. In this paper, we report investigations on radiation damage in fast inorganic scintillators, including BaF${}_2$, LYSO:Ce and PWO crystals, by mixed particles, including neutrons, γ-rays and protons, at the East Port of the Weapons Neutron Research facility of Los Alamos Neutron Science Center (WNR of LANSCE). In 2015, three groups of LFS (a type of LYSO) plates (6/each) of 14×14×1.5 mm${}^3$ were irradiated for 13.4, 54.5 and 118 days with fast neutron (>1 MeV) fluences of 0.22, 1.0 and 2.1 ×10${}^{15}$ n/cm${}^2$ plus ionization dose of 0.45, 2.0 and 4.3 Mrad, respectively. To evaluate the contribution from accompanying γ-rays quantitatively, we applied 5 mm Pb shielding to half samples for a comparison in 2016. Three groups of BaF${}_2$, LYSO and PWO plates of 10/15×10/15×5 mm${}^3$ were irradiated for 21.2, 46 and 120 days with fast neutron (>1 MeV) fluences of 0.39, 0.86 and 1.9 ×10${}^{15}$ n/cm2 plus ionization dose of 0.80, 1.7 and 3.9 Mrad, respectively. The results of this investigation show that LYSO and BaF${}_2$ are radiation hard against fast neutrons up to 2 ×10${}^{15}$ n/cm${}^2$ plus 4 Mrad ionization dose, and the ionization dose dominates the observed damages in these samples.

Secondary topics

radiation damage

Presentation materials

calor18_neutron_1.pdf