A Compton camera is being developed for the purpose of ion-range monitoring during hadrontherapy via the detection of prompt-gamma rays. The system consists of a scintillating fiber beam tagging ...hodoscope, a stack of double sided silicon strip detectors (90 Â 90 Â 2 mm 3 , 2 Â 64 strips) as scatter detectors, as well as bismuth germanate (BGO) scintillation detectors (38 Â 35 Â 30 mm 3 , 100 blocks) as absorbers. The individual components will be described, together with the status of their characterization.
A beam tagging hodoscope prototype made of squared 1 mm2 fibers arranged in two perpendicular planes and coupled to multi-anode photomultipliers has been studied using 65 MeV proton as well as 95 ...MeV/u 12C beams at various intensities. This hodoscope successfully provided 2D images of proton beams with a detection efficiency larger than 98% with logical OR condition between the two fiber planes. The detection efficiency with a coincidence between the two planes is close to 75% for beam intensities up to ∼1 MHz. Moreover, the timing resolution is around 1.8 ns FWHM. Overall, the performances show that such a technology is viable for beam monitoring during hadrontherapy.
The CLaRyS collaboration focuses on the development of gamma detectors for medical applications, in particular for what concerns the range monitoring in ion beam therapy. Part of the research program ...aims to implement two gamma-camera clinical prototypes, a multi-collimated camera and a Compton camera. A common absorber detector has been designed for the two prototypes, based on bismuth germanate (BGO) blocks, 3.5×3.8×3 cm3, assembled in various geometrical configurations to meet the application requirements. The surface of each block is streaked in a matrix of 8×8 pseudo pixels, which makes possible a position reconstruction via Anger logic from the signals collected by four read-out photo-multiplier tubes. The whole set of available blocks comes from a dismantled positron emission tomography system by Siemens, so that each single block must be tested and characterized in terms of space, time and energy response. We present in this work the implemented characterization method, which leads to a complete estimation of the block response via gamma source irradiations and data analysis devoted to a custom calibration for the imaging performance optimization of each detector module. A reference set of blocks has been completely characterized and showed very homogeneous responses: the average energy resolution is 25% FWHM at 511 keV and 20% FWHM at 1275 keV, the time resolution ranges between 3.9 and 5.3 ns FWHM and the spatial resolution has been verified to be limited to the pseudo-pixel size.
HARDROC is the front end chip designed to read out the Resistive Plate Chambers foreseen for the Digital HAdronic CALorimeter (DHCAL) of the future International Linear Collider. The very fine ...granularity of the calorimeter implies thousands of electronics channels per cubic meter which is a new feature of "imaging" calorimetry. Moreover, for compactness, chips must be embedded inside the detector making crucial the reduction of the power consumption down to 12 mu W per channel. This is achieved using power-pulsing and online zero-suppression. Around 800 HARDROC3 were produced in 2015. The overall performance and production tests will be detailed.
This paper presents our work on a 8-channel low noise Front-End electronic coupled to a Liquid Argon (LAr) TPC (Time Projection Chamber). Each channel consists of a Charge Sensitive Amplifier (CSA), ...a band pass filter and a 50 Ohms buffer as line driver. A serial link based on a 'i2c-like' protocol, provides multiple configuration features to the circuit by accessing slow control registers. In this paper, we describe the CSA, the shaper and the slow control part. The feedback network of the CSA is made of a capacitance and a resistor. Their values are respectively 250 fF and 4 Mfi. An input referred noise of, at most, 1500 e- rms must be achieved at -- 100 degree C with an input detector capacitance of 250 pF to ensure a correct measurement of the minimal signal of 18000e- (2.88 fC). The power consumption in this cryogenic setup must be less than 40 mW from a 3.3 V power supply.
Front end electronics and first results of the ALICE V0 detector Zoccarato, Y.; Tromeur, W.; Aguilar, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2011, Letnik:
626
Journal Article
Recenzirano
This paper gives a detailed description of the acquisition and trigger electronics especially designed for the V0 detector of ALICE at LHC. A short presentation of the detector itself is given before ...the description of the Front End Electronics (FEE) system, which is completely embedded within the LHC environment as far as acquisition (DAQ), trigger (CTP), and detector control (DCS) are concerned. It is able to detect on-line coincident events and to achieve charge (with a precision of 0.6 pC) and time measurements (with a precision of 100
ps). It deploys quite a simple architecture. It is however totally programmable and fully non-standard in discriminating events coming from Beam–Beam interaction and Beam-Gas background. Finally, raw data collected from the first LHC colliding beams illustrate the performance of the system.
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