  Isotope identification is a recurrent problem in gamma spectroscopy with high
purity germanium detectors. In this work, new strategies are introduced to
facilitate this type of analysis. Five criteria are used to identify the parent
isotopes making a query on a large database of gamma-lines from a multitude of
isotopes producing an output list whose entries are sorted so that the
gamma-lines with the highest chance of being present in a sample are placed at
the top. A metric to evaluate the performance of the different criteria is
introduced and used to compare them. Two of the criteria are found to be
superior than the others: one based on fuzzy logic, and another that makes use
of the gamma relative emission probabilities. A program called histoGe
implements these criteria using a SQLite database containing the gamma-lines of
isotopes which was parsed from WWW Table of Radioactive Isotopes. histoGe is
Free Software and is provided along with the database so they can be used to
analyze spectra obtained with generic gamma-ray detectors.
