Getting coincidence information from analysis of sum peaks in single Ge(Li) spectra

Analysis of sum peaks from single spectra obtained by a large volume Ge(Li) detector in many cases gives more coincidence information than traditional two-detector gamma-gamma coincidence measurements do. Approximate methods are given to obtain and use coincidence information from sum peaks of a single spectrum. The method gives coincidence count numbers of several order of magnitude higher than the traditional two-detector methods do, without the use of sophisticated multi-parameter analysis equipment and during comparable time. The sum peak analysis method requires much less instrumentation and memory capacity than the traditional methods, and multiple coincidences can also be measured with good efficiency. The possibilities and limitations of the sum peak analysis method are discussed and illustrated by different measurements. (author)