Subatomic Physics – AFRODITE

AFRican Omnipurpose Detector for Innovative Techniques and Experiments

Large -ray detector arrays are usually inefficient for the detection of photons below 20 keV. AFRODITE is a medium size array that has the unique capability of detecting both high and low energy photons with a reasonably high efficiency by combining large volume escape suppressed HPGe detectors (CLOVERS) with Low Energy Photon Spectrometer (LEPS) detectors. The AFRODITE frame is a rhombi cuboctahedron with 16 detector positions. The target chamber has the same geometry. AFRODITE comprises of up to 13 Clover detectors and can also be augmented with 8 LEPS for photons between 30 and 300 keV. Each Clover consists of four 50 x 70 mm HPGe crystals and the 13 Clovers subtend 18% of 4pi. The LEPS consist of four segmented planar Ge detectors of 2800 mm2 x 10 mm and they subtend 12.5% of 4pi.

The peak-to-total ratio for the detectors operated in add-back mode are ~45-50%, and a total efficiency at 1.3 MeV approximately 2.5%.  The array is operated with digital electronics in total data readout mode thus allowing for high throughput of data both per detector and in coincident data.

A range of ancillary detectors can be combined with AFRDOITE, such as Silicon CD-type detectors, recoil detectors, CsI type detectors for charged particles and also coupled with fast neutron detectors for time-of-flight discrimination for neutron reaction channels.

During 2018 AFRODITE will be upgraded to 14 clovers and by 2019 to 18 clovers and a new detector frame will be installed.  The fast-timing array of 8 LaBr3:Ce detectors can also be added to AFRODITE.