Accession Number:

AD0445239

Title:

A NEW THERMAL NEUTRON FLUX DENSITY STANDARD

Descriptive Note:

Corporate Author:

NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) DIV OF APPLIED PHYSICS

Personal Author(s):

Report Date:

1964-01-30

Pagination or Media Count:

14.0

Abstract:

Six Am241-Bealpha,n neutron sources are arranged around the central circumfejence of a graphite cylinder 28 cm in diameter by 26.5 cm high. This assembly is surrounded by 10 cm of polyethylene. The graphite cylinder contains an accessible central cavity, 5 cm in diameter by 5 cm high, for the calibration of thermal neutron detectors. The thermal neutron flux density in the cavity is measured by 4 pi beta-gamma coincidence counting of irradiated gold foils. A flux density below cadmium cutoff of nthvo 8700sq cmsec 1.5 was found. The uniformity is shown to be constant within the cavity to better than 0.5 over a cylindrical volume 5 cm in diameter by 2 cm high.

Subject Categories:

  • Fission Reactor Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE