GAMIDEN, a computer code, searches GAMTOT78, a file of gamma-ray spectra, for isotopes that match observed gamma energies. GAMIDEN lists the matching isotopes, eliminates isotopes that are not likely to be the source of the observed photons, and then lists the isotopes that are left-the likely candidates. The user makes any further analysis required to identify the actual source isotopes. The search procedure used in GAMIDEN is outlined as follows:
a- Given a set of observed photon energies, search the tabulated data for photons with the same energies, within experimental uncertainty. Isotopes that emit such photons form the initial list of possible sources of the observed photons.
b- Examine the tabulated spectrum of each isotope for gammas that have a higher probability of emission than the observed gamma has; presumably, such gammas should have been observed as well.
c- Examine energies of the other observed photons to see if these higher-probability gammas, if any, were, in fact, observed.
d- If the matching isotope's spectrum contains a higher-probability gamma and it was not observed, remove this isotope from the list of possible sources. Isotopes that survive this test constitute the final list of possible sources.