Introducing HYPERMET-PC for automatic analysis of complex gamma-ray spectra

In short time activation analysis, prompt gamma-activation analysis and in high rate gamma-ray spectroscopy in general, the shape parameters for peaks and background usually vary, rendering spectrum evaluation codes based on a fixed shape calibration unsuitable. An interactive version of the well-known, fully automatic gamma-ray spectrum analysis code HYPERMET has been developed in C+ + for the IBM-PC. It runs under MS-DOS, in conventional memory, and can handle up to 16k-channel spectra, recorded with CANBERRA's System 100 and AccuSpec and with ORTEC's ACE plug-in MCA cards. A Windows-like graphics environment is provided with mouse controlled pull-down menus, pop-up windows and rubber band expansion. All basic features of HYPERMET such as fully automatic peak search, nonlinear fitting of multiplets with automatically adjusted Gaussian peak widths, exponential tails and a complex background function have been retained. All details of the fitting procedure are recorded in a data base, hence any fitted region can be retrieved and modified interactively, even after a fully automatic spectrum evaluation. The program also provides an output peak list in SAMPO90 format for further processing. The latter format is widely used in a number of sample analysis programs such as KAYZERO, a software package for kg standardization in neutron activation analysis.