BGO Compton suppression detector
Parc Sud Galaxie
1, rue des Tropiques - BP 344
38435 ECHIROLLES Cedex - France


Any heavy metal collimator can be provided on request.

BGO crystal and surface preparation

BGO crystals are cut out of first grade boules with an attenuation length greater than 400 cm.
All crystals are prepared for optimum internal light collection and transmission towards photocathodes.

Phototubes and voltage divers

The back polished surface of each BGO element is coupled to a low noise phototube and its voltage divider.
Signal pulses and high voltage supply are connected on standard Lemo sockets. Phototubes are wired for a positive HV supply as this wiring gives a better noise figure (negative wiring on request).
An high voltage filter is provided also on each voltage divider. Gains of phototubes inside an anti-Compton are factory selected and equalized.

Energy resolution

<18% (FWHM) on side crystals inside the Compton suppression detector. Specification measured with a source placed inside the well in the center of the detector.
These measurements are made under the following conditions :

radiation line
pulse shaping
counting rate
: 137CS-662 keV
: l µs peaking time.
: 20 000 counts per second.

Peak to valley ratio

> 10 on crystals of the side elements, lower level energy limit smaller than 10 keV.
These measurements are made under the same conditions as for the energy resolution, but using an Americium source (59 KeV) screened by a 4 mm thick Aluminium filter (absorption of the low energy X-rays emitted by the source).

Suppression factor (SF)

SF > 0.55**, measured with a source placed at the focal point, the BGO anti-Compton surrounding a Ge detector.
These measurements are made with the 60CO 1.17 and 1.33 MeV radiation lines.
SF = area of the peak/area of the total spectrum*

: spectrum bounded at 100 keV
: figure subject to further refinement.


On every phototube or phototube pair can be attached on customer request a very fast low noise preamplifier/buffer - 50 ohms coaxial cable drivers.

gain bandwidth product
slew rate
output drive capability
voltage supply
current consumption
: 180 MHz
: 2 000 V/µs.
: 100 mA short circuit protected.
: ± 12 V compatible with the Nim standard.
: ± 20 mA.



40 anti-compton detectors
Picture shown :

40 anti-compton detectors
....Gasp experiment INFN Legnaro Italy

Cyberstar manufactures a full range of Compton suppression detectors. They can be adapted to any high purity Ge detector avaible on the market. The standard well diameters are Ø 79 and 100 mm but other dimensions can be made on request.
Well and external housing are made of aluminium alloy. They are strong and precisely machined. The back flange holds phototubes, Mu-metal shields and voltage dividers.

  Javascript DHTML Drop Down Menu Powered by  












Sapphire, sapphire crystal, sapphire crystal growth equipment, sapphire crystal furnace,radiation detector, ionisation chamber, scintillation detector, compton suppression, anti compton, x ray detector, gamma ray detector, cosmic suppression, crystal scintillation detector, detector using liquid scintillator, detector using plastic scintillator, scintillator, floating zone, gas blower, cyberstar, ionisation chambers, anti-compton detectors, hot air generator, gas tube,scintillation, radiation detection