Neutron Spectrometry Equipment
Centronic has
a contract with the Physikalisch-Technische Bundesanstalt (PTB) at Braunschweig,
Germany, for manufacture and supply of their designs of Bonner Spheres
and the later Neutron Multisphere Spectrometer (NEMUS).
Both products have the Centronic SP9 spherical neutron detector at their centre. In the case of the Bonner spheres the detector is surrounded by various thicknesses of Polyethylene whilst in the case of the NEMUS various thickness shells of Polyethylene, Copper, and Lead are assembled around the detector. These outer layers form a moderator to slow higher energy neutrons so that they can be measured by the SP9 detector, which is principally sensitive to thermal neutrons. Selection of the relevant thickness of the moderator allows measurement of various energy neutrons and the spherical nature of the system ensures as near as possible to a symmetrical response in all three dimensions.
In addition, Centronic can arrange for these products to be independently checked for mass and mechanical dimensions by PTB, the design authority, if required.
Further technical data on these products is published on the PTB website
Availability
Bonner Spheres – Available in outside diameters of 3.0,
3.5, 4.0, 4.5, 5.0, 6.0, 7.0, 8.0, 9.0, 9.5, 10.0, 12.0 inches. Individual
spheres or complete sets can be provided and intermediate sizes, though
not to the PTB standard, could be manufactured on request.
NEMUS – Available only as a complete instrument, having all relevant shells up to an outside diameter of 8.0 inches.
SP9 detectors – Centronic would normally include a single SP9 detector in any order for these items, though this could be omitted or additional detectors supplied if required.
Accessories – Connecting cables to fit the SP9 detector and interface
to any suitable equipment are available if required. The length and connector
required on the equipment end of the cable will need to be specified.