title: Measurement and calculation of the emission anisotropy of an X1 252Cf neutron source.
abstract: The authors have measured the emission anisotropy from a (252)Cf spontaneous fission neutron source in an X1 encapsulation. The measurements were made in a large low-scatter laboratory using a long counter, and data were taken at angles varying in 10 degrees steps from 0 degrees to 180 degrees relative to the cylindrical axis of the source. Corrections were made for room scatter, loss of neutrons due to air scatter and detector dead time. Calculations corresponding to these measurements were subsequently carried out using the two Monte Carlo codes MCNP and MCBEND, and the results are compared with the measurements and with each other.
authors.affiliation: Neutron Metrology Group, DQL, National Physical Laboratory, Hampton Road, Teddington, Mddx. TW11 0LW, UK. nigel.hawkes@npl.co.uk
authors.forename: N P
authors.initials: NP
authors.lastname: Hawkes
authors.forename: R
authors.initials: R
authors.lastname: Freedman
authors.forename: H
authors.initials: H
authors.lastname: Tagziria
authors.forename: D J
authors.initials: DJ
authors.lastname: Thomas
mesh_terms: D016880:Anisotropy; D002142:Californium / Q000032:analysis*; D003198:Computer Simulation; D019544:Equipment Failure Analysis; D008962:Models, Theoretical; D009502:Neutrons; D010315:Particle Accelerators / Q000295:instrumentation*; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D012542:Scattering, Radiation
chemical_list: D002142:Californium