Comparative Timing Performance of Large Volume Ge(Li) and HPGE Coaxial Detectors

The timing performance of several large (8% to 12% relative efficiency) Ge(Li) and HpGe coaxial detectors has been measured and compared. The Ge(Li) detectors are capable of timing resolution which is generally 10% to 30% better than that of the HpGe devices. This resolution capability can be attributed to the higher bias voltages which can be applied to the Ge(Li) detectors. However, in some applications that involve a wide dynamic range of energies, the HpGe devices can provide better timing resolution than their Ge(Li) counterparts. Advancements in the state of the art are expected to result in HpGe detectors that can provide timing performance equivalent to the performance of the best Ge(Li) devices.