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This article presents the development, full-characterization, and in-core testing of a miniature neutron detector for the investigation of highly localized in-core neutronics effects in the zero-power reactor CROCUS, operated at the Ecole Polytechnique federale de Lausanne (EPFL), Switzerland. A ZnS: 6LiF screen, mixing inorganic scintillator and neutron converter, with a surface of 1 mm2 and a thickness of 0.2 mm, was coupled with a silicon photomultiplier (SiPM) via a 10-m optical fiber. Analog readout electronics were adopted in this prototype version to process the SiPM output signal. A first campaign was carried out to assess the detection system capabilities in terms of neutron detection and counting in mixed neutron-gamma radiation fields. The miniature detector was thoroughly characterized with a Pu-Be source installed in the CARROUSEL facility and was subsequently tested inside a control rod guide tube of the CROCUS reactor in different reactor conditions, i.e., at shutdown, startup, and critical. The detector shows a linear response with a reactor power increase up to 6.5 W (i.e., around $10 {^{\mathrm{ 8}}}\,\,\text {cm}^{-2}\cdot \text {s}^{-1} $ total neutron flux) and excellent neutron counting capabilities, when compared to other localized detection systems available in CROCUS, such as the miniature fission chambers and single-crystal vapor deposited (sCVD) diamond detectors. In addition, the exposure of the miniature detector to a 60Co source with an activity of ~250 GBq, combined with the computation of the gamma flux in CROCUS with the Serpent 2 Monte Carlo code, confirmed the gamma insensitivity of the system in a mixed neutron-gamma field.

It is generally accepted that the count rate capability of ZnS:6LiF neutron detectors is strongly limited due to the long afterglow of the scintillator. However, realized as an array of individual sensitive elements (pixels) with independent signal readout and processing, such detectors can be operated with blocking times down to 1 $\mu \text{s}$ and promising counting rates up to 100 kHz/pixel. In this paper, we investigate how the long emission of the ZnS scintillator influences the detector performance apart from requiring a finite blocking time to suppress the probability of multiple counts. We also study the potential of the ZnO:6LiF scintillator with lower afterglow as a possible replacement of ZnS:6LiF.

An advanced neutron detection system for highly localized measurements in nuclear reactor cores was developed and tested in the Laboratory for Reactor Physics and System Behaviour (LRS) at the École polytechnique fédérale de Lausanne (EPFL), Switzerland, in close collaboration with the Detector group of the Laboratory for Particle Physics (LTP) at the Paul Scherrer Institute (PSI), Switzerland. The miniature-size detector is based on the coupling of a ZnS:6LiF scintillator/converter screen of 1 mm2 and 0.2 mm thickness with a 10-m optical fiber, the latter being connected to a silicon photomultiplier (SiPM). In this development version, the output signal is processed via analog read-out electronics. The present work documents the characterization of a detection system prototype in the mixedradiation fields o f t he C ARROUSEL f acility a nd i ts t esting in the CROCUS zero-power reactor operated at LRS. The fibercoupled scintillator shows a linear response with the reactor power increase up to 6.5 W (i.e. around 108 cm-2s-1 total neutron flux), with a s ubsequent l oss o f l inearity d ue t o e lectronic dead time of the analog system. Nevertheless, the detector shows excellent neutron counting capabilities whether compared to other localized detection systems available at LRS, e.g. miniature fission chambers and an sCVD diamond detector.

The efficiency of detecting signals from neutron absorption events (trigger efficiency) in detectors using ZnS scintillators loaded with neutron absorbers (6Li, 10B) is prone to be limited to values well below 100%: the non-transparency of the scintillator results in a wide dynamic range of the detected signals with some fraction always falling under the detection threshold set to satisfy the requirements on the gamma sensitivity, multi-count ratio, and the background count rate of the detector. The question of the limited trigger efficiency of such detectors is very seldom discussed in publications, yet it is very important as the product of the trigger efficiency and the probability of neutron absorption in the detector defines its overall efficiency. Available data indicate that the trigger efficiency of PMT-based detectors used in neutron diffraction experiments can be as low as $\sim 50$ %. In this work we evaluate the trigger efficiency of a SiPM-based ZnS:6LiF scintillation neutron detector developed to replace a 3He-detector of the POLDI time-of-flight diffractometer at the Paul Scherrer Institut in Switzerland. Requiring the gamma sensitivity with a 60Co source $\le 10^{-7}$ , the multi-count ratio $\le 10^{-3}$ with the detector dead time set to $10~\mu \text {s}$ , and the background count rate $\le 10^{-3}$ Hz we obtain the maximum possible trigger efficiency of $\sim 85$ % with the main restriction coming from the gamma sensitivity condition. Considering the neutron absorption probability of $\sim 80$ % at 1°A, the detector efficiency at this wavelength amounts to $\sim 70$ %, which is comparable to that of the current 3He-detector of the POLDI instrument.

In this paper we present the development of a one-dimensional multi-channel thermal neutron detection system for the application in neutron scattering instrumentation, e.g. strain-scanning diffractometers. The detection system is based on ZnS(Ag):6LiF neutron scintillator with embedded WLS fibers which are read out with a SiPM. A dedicated signal processing system allows us to suppress the SiPM dark counts and to extract the signals from the neutron absorption events. For a single-channel detection unit which represents the elementary building block of this detection system we achieved a neutron detection efficiency of ~65% at 1.2 A, a background count rate 10 − 3 Hz and a gamma-sensitivity 10 − 6 (measured with a 60Co source), while the dead time is ~20 μs and the multi-count ratio is 1 % . This performance was achieved even for SiPM dark count rates of up to ~2 MHz.

In this work we revisit the problem of the restricted count rate capability of thermal neutron detectors utilizing the ZnS scintillator. The effect of the long afterglow of the scintillator on the detector performance at high counting rates is studied. A count rate capability substantially above values currently regarded as feasible is demonstrated.

In the work presented here we built and evaluated a single-channel neutron detection unit consisting of a ZnS:$^6$LiF scintillator with embedded WLS fibers readout by a SiPM. The unit has a sensitive volume of 2.4 x 2.8 x 50 mm$^3$; 12 WLS fibers of diameter 0.25 mm are uniformly distributed over this volume and are coupled to a 1 x 1 mm$^2$ active area SiPM. We report the following performance parameters: neutron detection efficiency $\sim 65\,$% at $1.2\,��$, background count rate $< 10^{-3}$ Hz, gamma-sensitivity with $^{60}$Co source $< 10^{-6}$, dead time $\sim 20\,��$s, multi-count ratio $< 1\,$%. All these parameters were achieved up to the SiPM dark count rate of $\sim 2\,$MHz. We consider such detection unit as an elementary building block for realization of one-dimensional multichannel detectors for applications in the neutron scattering experimental technique. The dimensions of the unit and the number of embedded fibers can be varied to meet the specific application requirements. The upper limit of $\sim 2\,$MHz on the SiPM dark count rate allows to use SiPMs with larger active areas if required., 10 pages, 10 figures

In this new concept of 2-dimensional scintillation detector, the detector consists of an almost gapless assembly of individual and optically isolated ZnS/6LiF bars with embedded and uniformly distributed WLS fibers running from one end of the bar to the other. The longitudinal position is determined from the left-right asymmetry of the number of photons detected on both sides of the fibers while the transverse position is simply given by the transverse position of the bar. Special Y11(400)M WLS fibers with different attenuation lengths ranging from 13 cm to 30 cm have been developed by Kuraray for this specific application. Two different detection units have been built. Their performance in a neutron beam are presented and compared with simulation results.

Recently we reported on a high efficiency, low gamma-sensitivity, high count rate capable 1D neutron detector consisting of ZnS:6LiF scintillator readout with WLS-fibers coupled to SiPMs which showed a performance comparable with a 3He-based detector. In this work we discuss a possible extension of the developed technology to large area 2D detectors with high count rate capability suitable, for example, for the new generation of neutron powder diffraction instruments planned at the European Spallation Source.

A scalable 16-ch thermal neutron detection system has been developed in the framework of the upgrade of a neutron diffractometer . The detector is based on a ZnS: 6 LiF scintillator with embedded WLS fibers which are read out with SiPMs. In this paper, we present the 16-ch module, the dedicated readout electronics, a direct comparison between the performance of the diffractometer obtained with the current 3He detector and with the 16-ch detection module, and the channel-to-channel uniformity.

We present a digital signal processing system based on a photon counting approach which we developed for a thermal neutron detector consisting of ZnS(Ag):6LiF scintillating layers read out with WLS fibers and SiPMs. Three digital filters have been evaluated: a moving sum, a moving sum after differentiation and a digital CR-RC^4 filter. The performances of the detector with these filters are presented. A full analog signal processing using a CR-RC^4 filter has been emulated digitally. The detector performance obtained with this analog approach is compared with the one obtained with the best performing digital approach.

The aim of this paper was to characterize two deep-diffusion avalanche photodiode (APD) arrays for positron emission tomography (PET). Two different prototypes developed by radiation monitoring devices (RMD) were investigated. Quantum efficiency was determined as a function of wavelength in the visible-ultraviolet rays region. Capacitance was determined as a function of bias. Dark current and gain were measured at several fixed temperatures versus bias. Finally, bulk and surface contributions to the dark current were estimated.

The Crystal Clear Collaboration has designed and is building a high-resolution small animal PET scanner. The design is based on the use of the Hamamatsu R7600-M64 multi-anode photomultiplier tube and a LSO/LuYAP phoswich matrix with one to one coupling between the crystals and the photo-detector. The complete system will have 80 PM tubes in four rings with an inner diameter of 137 mm and an axial field of view of 110 mm. The PM pulses are digitized by free-running ADCs and digital data processing determines the gamma energy, the phoswich layer and even the pulse arrival time. Single gamma interactions are recorded and coincidences are found by software. The gantry allows rotation of the detector modules around the field of view. Simulations, and measurements a 2×4 module test set-up predict a spatial resolution of 1.5 mm in the centre of the field of view and a sensitivity of 5.9% for a point source in the centre of the field of view.

Characteristics of recently developed arrays of avalanche photodiodes (APDs) are investigated with the perspective of replacing photomultiplier tubes in small animal positron emission tomography. Quantum efficiency of the APDs is measured as a function of wavelength in the VIS–UV region. Gain and capacitance are determined at fixed temperatures as a function of bias voltage. Finally, bulk and surface contributions to the dark current are estimated.

Two single channel detection units for thermal neutron detection are investigated in a neutron beam. They consist of two ZnS/${}^6$LiF scintillating layers sandwiching an array of WLS fibers. The pattern of this units can be repeated laterally and vertically in order to build up a one dimensional position sensitive multi-channel detector with the needed sensitive surface and with the required neutron absorption probability. The originality of this work arises from the fact that the WLS fibers are read out with SiPMs instead of the traditionally used PMTs or MaPMTs. The signal processing system is based on a photon counting approach. For SiPMs with a dark count rate as high as 0.7 MHz, a trigger efficiency of 80% is achieved together with a system background rate lower than ${10}^{-3}$ Hz and a dead time of 30 $\mu$s. No change of performance is observed for neutron count rates of up to 3.6 kHz., Comment: Submitted to Nuclear Instruments and Methods A

A thermal neutron detector based on ZnS(Ag)/6LiF scintillator, wavelength-shifting fibers (WLS) and silicon photomultipliers (SiPM) is under development at the Paul Scherrer Institute (PSI) for upgrading the POLDI instrument, a pulse-overlap diffractometer. The design of the detector is outlined, and the measurements performed on a single channel prototype are presented. An innovative signal processing system based on a photon counting approach is under development. Its principle of operation is described and its performances are evaluated on the basis of a Monte Carlo simulation., 8 pages, 15 figures, to be published in the Proceedings of the International Workshop on Neutron Optics and Detectors (NOP&D 2013), 2-5 July 2013, Munich (Ismaning), Germany

International audience; This paper presents the count rate measurements obtained with the Lausanne partial ring ClearPET scanner demonstrator and compares them against GATE Monte Carlo simulations. For the present detector setup, a maximum single event count rate of 1.1 Mcps is measured or a 250–750 keV energy window. This corresponds to a coincidence count rate of approximately 22 kcps. Good agreements are observed between measured and simulated data. Count rate performance, including Noise Equivalent Count (NEC) curves, are determined and extrapolated for a full ring ClearPET design using GATE Monte Carlo simulations. For a full ring design with three rings of detector modules, NEC is peaking at about 70 kcps for 20 MBq.

This paper presents the measurements obtained with the partial ring Lausanne ClearPET scanner demonstrator and compares them against GATE Monte Carlo simulations. Radial and tangential spatial resolutions were measured up to 4 cm from the scanner axis. FWHM spatial resolutions range from 1.3 mm on axis to 2.6 mm at 4 cm from the axis. Excellent agreement is observed between the measured and simulated spatial resolutions. Coincidence time resolution of the LSO/LuYAP detector modules amounts to 4.8 ns FWHM. Absolute sensitivity measured for two detector modules facing each other amounts to 0.068%, compared to 0.070% simulated for 7.1 g/cc LuYAP with 70% lutetium atomic fraction. Simulation of a 4-ring ClearPET scanner with 20 LSO/LuYAP detector modules per ring gives an absolute sensitivity of 4.42%. DOI effect is shown on a reconstructed image of a Mini-Derenzo phantom. Images of a [ 18F]FDG rat brain scan are presented

In this work results of ongoing research are presented for the LYSO/LuYAP phoswich solution adapted in the ClearPETtrade scanner with depth-of-interaction capability. The use of artificial neural network has been found as a very efficient phoswich crystal layer identification method that works for scintillators used at present, as well as on prospective materials. The LYSO/LuAP and LYSO/GSO phoswiches have been identified as a promising candidates for future PET scanners

The ClearPET/spl trade/ Neuro is the first full ring scanner within the Crystal Clear Collaboration (CCC). It consists of 80 detector modules allocated to 20 cassettes. LSO and LuYAP:Ce crystals in phoswich configuration in combination with position sensitive photomultiplier tubes are used to achieve high sensitivity and realize the acquisition of the depth of interaction (DOI) information. The complete system has been tested concerning the mechanical and electronical stability and interplay. Moreover, suitable corrections have been implemented into the reconstruction procedure to ensure high image quality. We present first results which show the successful operation of the ClearPET/spl trade/ Neuro for artefact free and high resolution small animal imaging. Based on these results during the past few months the ClearPET/spl trade/ Neuro System has been modified in order to optimize the performance.

This paper describes the LSO/LuYAP phoswich detector head developed for the ClearPET small animal PET scanner demonstrator that is under construction in Lausanne within the Crystal Clear Collaboration. The detector head consists of a dual layer of 8/spl times/8 LSO and LuYAP crystal arrays coupled to a multi-anode photomultiplier tube (Hamamatsu R7600-M64). Equalistion of the LSO/LuYAP light collection is obtained through partial attenuation of the LSO scintillation light using a thin aluminum deposit of 20-35 nm on LSO and appropriate temperature regulation of the phoswich head between 30/spl deg/C to 60/spl deg/C. At 511keV, typical FWHM energy resolutions of the pixels of a phoswich head amounts to (28/spl plusmn/2)% for LSO and (25/spl plusmn/2)% for LuYAP. The LSO versus LuYAP crystal identification efficiency is better than 98%. Six detector modules have been mounted on a rotating gantry. Axial and tangential spatial resolutions were measured up to 4 cm from the scanner axis and compared to Monte Carlo simulations using GATE. FWHM spatial resolution ranges from 1.3 mm on axis to 2.6 mm at 4 cm from the axis.

The Crystal Clear Collaboration has designed and built a family of high resolution small animal PET scanners. These were designed to be used in research laboratories and provide maximum modularity and flexibility. The source code of the data acquisition and reconstruction software is freely available to the users. The design is based on the use of the Hamamatsu R7600-M64 multi-anode photomultiplier tube and an LSO/LuYAP phoswich matrix with one-to-one coupling between the crystals and the photo-detector. A complete system has 80 PMT tubes in four rings with a minimum inner diameter of 137 mm and an axial field of view of 110 mm. The detectors are rotating over 360 degrees so that partially filled ring geometries can be used. This greatly simplifies the combination of PET with other imaging modalities. Single gamma interactions are recorded in list mode format and coincidences are found by software.

Contents. Preface S. Tavernier.-A Look at Medical Imaging Trends through the Eyes of a Medical Doctor S.S. Makeyev.- Introduction.-Historical Aspect of Nuclear Medicine.-Nowadays in Nuclear Medicine.-Perspectives of Nuclear Medicine Imaging.- New Trends in X-Ray CT Imaging R. Deych and E. Dolazza.- Present Status of X-Ray CT.-Detector Instrumentation in Medical CT.- Scintillator.-Photodetectors.-Future Evolution of Data Measurement Systems.- The Evolution of Spect- from Anger to Today and Beyond W.W. Moses, A. Gektin et al.- Introduction.-General Considerations.-SPECT.- The Anger Camera.-Optimizing Positioning in Anger Cameras.- Collimators.-Scintillators for Spect.- Recently Developed Scintillator Materials.- Conclusion.- New Trends in PET Detector Developments P.Lecoq.- Introduction.-PET Based Molecular Imaging.-Improving Sensitivity.- Improving Spatial and Temporal Resolution.-Multimodaility and Multifunctionality.-New Conversion Materials.- New Photodetectors.-Highly Integrated and Low Noise Electronics.-Intelligent and Triggerable Data Acquisition Systems.-Simulation Software.-New Reconstruction and Visualisation Algorithms.-Conclusion.-Semiconductor Detectors in Radiation Medicine: Radiotherapy and related Applcations A.B. Rosenfeld.- Introduction.-Integral Semiconductor Dosimetry in Radiation Therapy.-Mosfet Detectors.-Semiconductor Radiation Detectors in Hadron Therapy.- Semiconductor Radiation Detectors for Microdosimetry in Radiation Therapy.-Application of Scintillator Based Detector in Radiation Therapy.-Conclusion.-First Results with the ClearPET small Animal PET Scanners S. Tavernier et al.- Introduction.-Description of the ClearPET Scanners.-Measured Performance and Comparison with Monte Carlo Simulations.- Image Reconstruction.-Conclusions.-Investigation of Crystal Identification Methods for ClearPETTM Phoswich Detector D. Wisniewski et al.- Introduction.-Measurement Setup.-Crystal Identification Methods.- Experimental Results.- Conclusions.- Directions in Scintillation Materials Research P. Dorenbos.- Introduction.-Historic Developments.- Fundamental Limits.- Directions in Scintillation Materials Research.-Summary and Conclusions.-Scintillation Detectors for Medical and Biology Applications: Materials, Design and Light Collection Conditions M. Globus, B. Grinyov.- Introduction.-2. Some Features and Regularities of Light Collection in Scintillators.- Medical Diagnostics Instrumentation.- Thin Scintillation Films for Biological Microtomography. Conclusions.- Current and Future Use of LSO: CE Scintillators in PET C.L. Melcher et al.- Introduction.-Physical Properties.- Scintillation Properties.-Crystal Growth.-Detector Design.- Future Uses of LSO: CE in PET.-Conclusion.-Inorganic Scintillators in Positron Emission Tomography C.W.E. van Eijk.- Introduction.-Inorganic Scintillators.- Position Resolution and Depth of Interaction.-Coincidence-Time Resolution, Random Coincidences, Time of Flight and Dead Time.-Conclusion.-Crystal Fibers and thin Films for Imaging Applications C. Pedrini and C. Dujardin.-. Introduction.-Single Crystal Fibers.- Scintillating Thin Films Deposited on Substrate.- Scintillation thin Layers created by Irradiation.-Conclusions. Non-Proportionality and Energy Resolution of Scintillation Detectors M. Moszynski.-Introduction.-Outline of the Problem.Study of Energy Resolution and Non-Proportionality.- Discussion and Conclusions.

The paper describes the LSO/LuYAP phoswich detector head developed for the ClearPET small animal PET scanner demonstrator that is under construction within the Crystal Clear Collaboration. The detector head consists of a dual layer of 8/spl times/8 LSO and LuYAP crystal arrays coupled to a multi-channel photomultiplier tube (Hamamatsu R7600-M64). Equalisation of the LSO/LuYAP light collection is obtained through partial attenuation of the LSO scintillation light using a thin aluminium deposit of 20-35 nm on LSO and appropriate temperature regulation of the phoswich head between 30 to 60 /spl deg/C. At 511 keV, typical FWHM energy resolutions of the pixels of a phoswich head amounts to (28/spl plusmn/2)% for LSO and (25/spl plusmn/2)% for LuYAP. The LSO versus LuYAP crystal identification efficiency is better than 98%. Six detector modules have been mounted on a rotating gantry. Axial and tangential spatial resolutions were measured up to 4 cm from the scanner axis and compared to Monte Carlo simulations using GATE. FWHM spatial resolution ranges from 1.3 mm on axis to 2.6 mm at 4 cm from the axis.

Neutrinos, Imagerie; Second generation high-performance PET scanners, called ClearPET$^{TM}$, have been developed by working groups of the Crystal Clear Collaboration (CCC). High sensitivity and high spatial resolution for the ClearPET camera is achieved by using a phoswich arrangement combining two different types of lutetium-based scintillator materials: LSO from CTI and LuYAP:Ce from the CCC (ISTC project). In a first ClearPET prototype, phoswich arrangements of 8$\times$8 crystals of 2$\times$2$\times$10 mm$^3$ are coupled to multi-channel photomultiplier tubes (Hamamatsu R7600). A unit of four PMTs arranged in-line represents one of 20 sectors of the ring design. The opening diameter of the ring is 120 mm, the axial detector length is 110 mm. The PMT pulses are digitized by free-running ADCs and digital data processing determines the gamma energy, the phoswich layer and even the exact pulse starting time, which is subsequently used for coincidence detection. The gantry allows rotation of the detector modules around the field of view. Preliminary data shows a correct identification of the crystal layer about (98$\pm$1)%. Typically the energy resolution is (23.3$\pm$0.5)% for the luyap layer and (15.4$\pm$0.4)% for the lso layer. Early studies showed the timing resolution of 2 ns FWHM and 4.8 ns FWTM. the intrinsic spatial resolution ranges from 1.37 mm to 1.61 mm full-width of half-maximum (FWHM) with a mean of 1.48 mm FWHM. further improvements in image and energy resolution are expected when the system geometry is fully modeled.

A 2nd generation high performance small animal PET scanner, called ClearPET/spl trade/, has been designed and a first prototype is built by working groups of the Crystal Clear Collaboration (CCC). In order to achieve high sensitivity and maintain good uniform spatial resolution over the field of view in high resolution PET systems, it is necessary to extract the depth of interaction (DOI) information and correct for spatial degradation. The design of the first ClearPET/spl trade/ Demonstrator based on the use of the multi-anode photomultiplier tube (Hamamatsu R7600-M64) and a LSO/LuYAP phoswich matrix. The two crystal layers of 8*8 crystals (2*2*10 mm/sup 3/) are stacked on each other and mounted without light guide as one to one on the PMT. A unit of four PMTs arranged in-line represents one of 20 sectors of the ring design. The opening diameter of the crystal ring is 137 mm, the axial detector length is 110 mm. The PMT pulses are digitized by free-running ADCs and digital data processing determines the gamma energy, the phoswich layer and even the pulse arrival time. Single gamma interactions are recorded and coincidences are found by software. The gantry allows rotation of the detector modules around the field of view. The measurements have been done using the first LSO/LuYAP detector cassettes.

We report on the possibility of using Silicon Photomultipliers (SiPMs) to detect the scintillation light from neutron conversion in ZnS:6LiF scintillators. The light is collected by wavelength-shifting fibers embedded into the scintillator. The difficulty of extracting neutron signals in the presence of high dark count rates of the SiPMs is addressed by applying a dedicated processing algorithm to analyze the temporal distribution of the SiPM pulses. With a single-channel prototype detection unit we demonstrate a very good neutron signal extraction at SiPM dark count rates of about 1 MHz., Comment: 13 pages, 8 figures; a new section is added, additional discussions and explanations in other sections

The aim of this study is to characterize new prototype avalanche photodiode (APD) arrays for positron emission tomography (PET). Two different APD array prototypes developed by Radiation Monitoring Device (RMD) are investigated. Quantum efficiency of the APD is measured as a function of wavelength in the VIS-UV region. Capacitance is determined as a function of bias voltage. Dark current and gain are measured at fixed temperatures as a function of bias voltage. Finally, bulk and surface contributions to the dark current are estimated.

The ClearPET initiative is a project being undertaken by working groups of the Crystal Clear Collaboration (CCC). Its aim is to develop a second-generation high performance small animal positron emission tomograph. The ClearPET camera is expected to provide both high sensitivity and high spatial resolution. It uses a phoswich arranging combining two types of lutetium-based scintillator materials: LSO and LuYAP:Ce. Based on the same detector modules different designs from each collaboration partner are realized for their associated medical institutes. Each dedicated version is expressed by the name ClearPET plus an extension. The ClearPET Neuro scanner is a dedicated small animal scanner to allow measurements of signal transduction in non- human primates under physiological conditions. This scanner is build by working groups of the Research Center Julich (FZJ). The gantry allows rotation of the detector modules as well as tilting by 90 degrees to measure non-human primates in an upright sitting position. The opening diameter of the ring is variable between 130mm and 300mm, the axial detector length is 110mm.