The Internal Conversion Electron Ball Array (ICEBall) was initially developed by J.X. Saladin and M.P. Metlay at the University of Pittsburgh and later moved to Yale University. When the nuclear laboratory at Yale was closed, ICEBall found new home and got recommissioned at the University of Notre Dame. ICEBall at ND has undergone multiple repairs and upgrades to restore its capabilities and improve its overall efficiency. In addition, a LN2 autofill system has been developed for more efficient and reliable running during experiments.
ICEBall consists of six annular Si(Li) detectors that are 5 mm thick and have an active area of 750 mm2 each. In front of each detector, there is a mini-orange filter which is comprised of a central tungsten absorber surrounded with up to six wings of permanent samarium cobalt magnets. ICEBall has a measured absolute efficiency of 15% at 356 keV and a resolution of 3-5 keV FWHM for electrons.