4 research outputs found
Recent progress in oxide scintillation crystals development by low-thermal gradient Czochralski technique for particle physics experiments
No full textInternational audienceModern particle physics experiments call for high performance scintillation detectors with unique properties: radiation-resistant in high energy and astrophysics, highly radiopure, containing certain elements or enriched isotopes in astroparticle physics. The low-thermal gradient Czochralski (LTG CZ) crystal growth technique provides excellent quality large volume radiopure crystal scintillators. Absence of thermoelastic stress in the crystal and overheating of the melt in the LTG CZ method is particularly significant in production of crystalline materials with strong thermal anisotropic properties and low mechanical strength, with a very high yield of crystalline boules and low losses of initial charge, crucially important in production of crystal scintillators from enriched isotopes for double beta decay experiments. Here we discuss progress in development of the well known scintillators (Bi(4)Ge(3)O(12) (BGO), CdWO(4), ZnWO(4), CaMoO(4), PbMoO(4)), as well as R{&}D of new materials (ZnMoO(4), Li(2)MoO(4), Na(2)Mo(2)O(7)) for the next generation experiments in particle physics
Study of Dark Matter with directionality approach using ZnWO
No full textLow-background anisotropic scintillators represents an innovative approach to study the presence, in the galactic halo, of those Dark Matter (DM) candidate particles able to induce just nuclear recoils, by exploiting the directionality approach. ZnWO4 crystal scintillators are particularly well-suited for such investigations, since the light output and scintillation pulse shape vary depending on the angle of incidence of heavy particles (e.g., α particles and nuclear recoils) relative to the crystal axes. Due to this anisotropic behavior, a signal induced by those DM candidates can be investigated in two independent modes: studying the directionality variation both of the signal rate and of the pulse shape discrimination from the γ/β radiation (that does not give rise to any anisotropic effects). Additionally, the detector’s sensitivity spans a wide range of DM masses, attributed to the differing atomic masses of its target nuclei (Zn, W, and O). Building on these characteristics, the ADAMO project carried out new studies to examine the anisotropic response of ZnWO4 scintillators to α particles and nuclear recoils induced by neutron scattering. A summary of these investigations are presented in this paper
Dark matter directionality approach using ZnWO crystal scintillators
No full textThe development of low-background anisotropic detectors can offer a unique way to study those Dark Matter (DM) candidate particles able to induce nuclear recoils through the directionality technique. Among the anisotropic scintillators, the ZnWO has unique features and is an excellent candidate for the purposes. Both the light output and the scintillation pulse shape depend on the impinging direction of heavy particles with respect to the crystallographic axes and can supply two independent modes to study the directionality and discriminate radiation. Measurements to study the anisotropic and scintillation performances of ZnWO are reported
