C-styles and CP-styles
F EATURES
SCIONIX C-style detector assemblies basically consist of a scintillation crystal which
is machined and mounted in a housing of aluminum, stainless steel or copper. In case of
hygroscopic crystals the assembly is sealed by a glass or quartz window for optical
coupling to a photomultiplier tube or other light detection device. C-style assemblies can
be manufactured from low background materials (LB steel or copper).
The standard housing thickness is 0.8 mm. C-style assemblies can be provided in a
ruggedized version (CR-styles) or designed for use at elevated temperatures.
The optical window can be extended in height or tapered to form an optical light guide
to a different diameter than that of the crystal. For optimum energy resolution, the
diameter of the crystal is chosen equal or slightly smaller than the diameter of the PMT.
C-style assemblies are intended for use in combination with customer's photomultiplier
tube in demountable assemblies. The optical contact to the PMT is accomplished by using
optical coupling compound or customer's own optical glue.
Housings can be equipped with flanges or grooves for O-rings in order to facilitate a
demountable coupling to the PMT and its housing.
C-style assemblies can be provided with an axial well and are then called
CP-styles, or with thin (30 mm thick) Al entrance windows at the flat side
of the crystal, then called CA-styles.
Standard inner well dimensions for CP-style assemblies are
51 CP 51 : 25.4 mm diameter, 39.3 mm deep
16.6 mm diameter, 39.3 mm deep
76 CP 76 : 25.4 mm diameter, 52 mm deep
The standard well thickness is 0.3 mm (Aluminium).
APPLICATION
Standard C-style assemblies are used for detection of gamma-rays and X-rays between 30
keV and 2 MeV. For higher energies, BGO can be chosen as the scintillator of choice in
which case the optical window is omitted. CP-styles are used in well counters for e.g.
medical applications or wipe test detectors. |