RSIC COMPUTER CODE PSR-032
1. NAME AND TITLE
CUPED: Scintillation Spectrometer Polyenergetic Gamma Photon Experimental Distributions
CUPED is a much modified version of CUBED.
NUS Corporation, Rockville, Maryland.
3. CODING LANGUAGE AND COMPUTER
Fortran IV; IBM 360/75/91.
4. NATURE OF PROBLEM SOLVED
CUPED unfolds sodium-iodide (thallium-activated) scintillation spectrometer polyenergetic gamma
photon experimental distributions. It is designed to analyze the combination bremsstrahlung and
monoenergetic gamma radiation field of cylindrical radioisotope power generators.
5. METHOD OF SOLUTION
CUPED generates the detector system response matrix function and applies it to the monoenergetic spectral components discretely and to the bremsstrahlung iteratively. It corrects for iodine K X-ray escape, detector non-linearity, system drift, source decay, background, and detection efficiency. Results are presented in digital form for differential and integrated photon number and energy distributions and exposure dose.
The standard spectra are normalized with respect to photopeak pulse-height and area and their
photopeaks subtracted to obtain normalized Compton continua. The response matrix vectors are
determined at each energy by interpolating the normalized continua and computing the associated
Gaussian photopeaks. The thus interpolated vectors are redistributed in pulse-height to correspond to
the detector system energy response and to satisfy the requirements of the spectra to be unfolded.
Quadratic interpolation of the normalized continua is carried out either directly for gamma photon
energies < 0.6616 MeV or by a method of parts, described in this report, for energies > 0.6616
6. RESTRICTIONS OR LIMITATIONS
7. TYPICAL RUNNING TIME
No study has been made by RSIC of typical running times for CUPED.
8. COMPUTER HARDWARE REQUIREMENTS
CUPED is operable on the IBM 360/75/91 computers.
9. COMPUTER SOFTWARE REQUIREMENTS
A Fortran IV compiler is required.
J. J. Steyn, U. Born, J. T. Strahl, and R. Huang, "Code CUPED: A Code to Unfold Scintillation Spectrometer Polyenergetic Gamma Photon Experimental Distributions," NUS-557 (September 1969).
J. J. Steyn and D. G. Andrews, "A Comprehensive System for Computer Gain Changing of
Scintillation Spectra," J. Nucl. Sci. Eng. Vol. 35, No. 3 (March 1968) 394-403.
11. CONTENTS OF CODE PACKAGE
Included are the referenced documents and one (1.2MB) DOS diskette which contains the source
code and sample problem input and output.
12. DATE OF ABSTRACT
KEYWORDS: GAMMA-RAY SPECTRUM ANALYSIS; UNFOLDING