A simulation study of the Cosmic Ray Inspection and Passive Tomography (CRIPT) muon spectrometer


  1. Waller, D.
Corporate Authors
Defence R&D Canada - Ottawa, Ottawa ONT (CAN)
The Cosmic Ray Inspection and Passive Tomography (CRIPT) for Special Nuclear Material (SNM) Detection project is investigating the effectiveness of muon scattering tomography for detecting SNM and dense radiation-shielding materials like lead. The goal of CRIPT is to design, build and test a large-scale prototype system that uses naturally occurring cosmic-ray-induced muons to image a volume of interest. Measuring the momenta of muons on an event-by-event basis should reduce the required imaging times significantly. This paper describes relatively simple simulations of the performance of different magnetized and unmagnetized muon spectrometer designs. An unmagnetized spectrometer uses the multiple Coulomb scattering of a muon through known absorbers to estimate the muon's momentum, p. A magnetized spectrometer measures p using both multiple scattering and the magnetic deflection inside magnetized iron absorbers. Using only multiple scattering measurements, the resolution of 1/p is 50% or better. The gain in resolution obtained by magnetizing the iron absorbers is not very significant (less than 10% relative improvement) unless the magnetic field in the iron is very high (> 1.0 T). An unmagnetized spectrometer appears to be the preferred choice for CRIPT as it is simpler and likely more cost-effective to implement.

Il y a un résumé en français ici.

Report Number
DRDC-OTTAWA-TM-2010-168 — Technical Memorandum
Date of publication
01 Oct 2010
Number of Pages
Electronic Document(PDF)

Permanent link

Document 1 of 1

Date modified: