a selected Photomultiplier tube (PMT), directly and permanently coupled to the crystal, with a high refractive index optical coupling medium.
a mu-metal shield around the PMT to protect against external magnetic fields.
hermetically sealed in a low mass light tight housing, with a thin aluminium (typically 0.5mm thick) entrance window.
Advantages
Simple plug-in unit.
Permanent light sealing ( no PMT damage).
Selection of the PMT (gain stability and linear response) and direct coupling of the PMT on the crystal to guarantee consistent and superior energy resolution.
Applications
General gamma ray counting and spectroscopy in the range of 15 KeV to 5 MeV.
Common configurations
Optimum configurations are achieved with the following crystal - PMT sizes :
PMT diameter
Crystal sizes
1.5"
F = 38mm to 51mm
H = on request
2"
F = 38mm to 51mm
H = on request
3"
F = 63.5mm to 76mm
H = on request
5"
F = 102mm to 127mm
H = on request
Options
Electronics: Voltage Divider, Preamplifier and High Voltage devices can be incorporated on request.
Premium energy resolution assemblies: an external focusing potentiometer can be added to adjust and improve the photocathode optics.
Other configurations
Axial well Scintibloc
The most efficient configuration.
Application: high gamma ray counting for a small volume of liquid or solid samples (Radio-Immuno Assay).
Well sizes: diameter and length on request.
Standard wall thickness : 0.25mm.
Transversal well Scintibloc
The second most efficient configuration: the hole is machined perpendicular to the crystal axis.
Application: high gamma ray counting for a small volume of liquid or solid samples, for fuel flow studies and scanning fuel rods.
Well sizes: 0.25mm thick, diameter and length on request.
Rugged assemblies designed to operate in severe temperature, vibration and shock conditions.
Sealed assemblies made to resist hydrostatic pressure.
Thin entrance window assemblies: crystal thickness, entrance window type and thickness are defined according to the low-energy gamma and X-Rays to be detected.
Low background assemblies manufactured with selected low background components.
