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PET probeThe passive PET probe CXS-OP-SZB-PET is derived from the standard probe CXS-OP-SZBN. The PET-probe is for the detection of higher-energy radiation like for example 131J (EGamma = 365 keV) and for the direct detection of radiation resulting from the positron annihilation of 511 keV.

In order to achieve nearly as good collimation as for the standard probes for 140 keV, the collimator sleeves / tips are dimensioned accordingly. The PET probe is available in two versions: with a probe diameter of 22 mm (side shielding 75% @ 511keV) and 31 mm (side shielding 93% @ 511 keV). Both models have a sensitivity > 5000 counts / s / MBq at a standard dihedral angle of 45°. The collimators are built in stainless steel tubes that can be screwed off and autoclaved separately.

When used intra-operatively the probe has to be protected by a sterile latex coating. As, for example, those used in ultrasound diagnostics.

Technical Data

Detector CsI:Tl-scintillation Ø 6 mm x 8 mm long, read-out by a 20 mm2 pin-photodiode
Gamma-energy Range 60 keV … > 511 keV
Dimensions Length: 220 mm
Length of cable: 3 m
Diameter hand piece: 20 mm
Diameter tip: 22 mm, weight: about 10 ounce (270 g)
Diameter tip: 31 mm, weight: about 16 ounce (450 g)
Detection efficiency 35% @ 511 keV
Special Features 2 different collimator sleeves available

Collimation and Side Shielding



  1. lateral 6.65 mm wall thickness, rear 8 mm wall thickness: side shielding = 75 % @ 511keV (18F, 68Ga, FDG)
  2. lateral 11.15 mm wall thickness, rear 8 mm wall thickness: side shielding = 93 % @ 511 keV (18F; 68Ga; FDG)
Dihedral angle (FOV) Standard 40° FWHM

Background Sensitivity

Zero effect < 0.1 cps = 6 c/min


The sensitivity of the probe for 511 keV is determined under standard measurement conditions. The figure shows the sensitivity in relation from the source to the probe tip. The probe CXS-OP-SZB-PET has a good sensitivity > 5,500 counts/s/MBq.

Angular Resolution

The angular resolution with a standard collimator (40°) is determined in the near field (distance: 3 cm) and in the far field (distance: 10 cm).

Spatial Resolution

The spatial resolution is determined in the near field (distance: 1 cm). The probe has an excellent spatial resolution < 15 mm.

Energy Spectra

The energy spectra of the PET-probe CXS-OP-SZB-PET, recorded for 18F (511 keV)
18F (511 KeV-PET): is a division of Nuclear Fields USA Corp.
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