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Purpose: To demonstrate a proton imaging system based on well-established fast scintillator technology to achieve high performance with low cost and complexity, with the potential of a straightforward translation into clinical use. Methods: The system tracks individual protons through one (X, Y) scintillating fiber tracker plane upstream and downstream of the object and into a 13 cm-thick scintillating block residual energy detector. The fibers in the tracker planes are multiplexed into silicon photomultipliers (SiPMs) to reduce the number of electronics channels. The light signal from the residual energy detector is collected by 16 photomultiplier tubes (PMTs). Only four signals from the PMTs are output from each event, which allows for fast signal readout. A robust calibration method of the PMT signal to residual energy has been developed to obtain accurate proton images. The development of patient-specific scan patterns using multiple input energies allows for an image to be produced with minimal excess dose delivered to the patient. Results: The calibration of signals in the energy detector produces accurate residual range measurements limited by intrinsic range straggling. We measured the water-equivalent thickness (WET) of a block of solid water (physical thickness of 6.10 mm) with a proton radiograph. The mean WET from all pixels in the block was 6.13 cm (SD 0.02 cm). The use of patient-specific scan patterns using multiple input energies enables imaging with a compact range detector. Conclusions: We have developed a prototype clinical proton radiography system for pretreatment imaging in proton radiation therapy. We have optimized the system for use with pencil beam scanning systems and have achieved a reduction of size and complexity compared to previous designs., 11 pages, 8 figures, Accepted Manuscript

Nucl.Instrum.Meth.A634:8-46,2011; This paper describes the mechanical design, the readout chain, the production, testing and the installation of the Silicon Microstrip Tracker of the D0 experiment at the Fermilab Tevatron collider. In addition, description of the performance of the detector during the experiment data collection between 2001 and 2010 is provided.

We present results on the operation and performance characteristics of the Metal/Resistor/Semiconductor (MRS) photodiode. These include measurements of threshold characteristics, noise frequency, dependence of signal amplitude on the applied voltage and temperature, and stability as a function of time and radiation dose. The single photoelectron separation for this photosensor is demonstrated with a light-emitting diode. The response of the photodetector to light produced in scintillator is studied with cosmic ray muons and a 106Ru source. In addition, fiber-sensor alignment issues were evaluated. The results are promising and illustrate the potential use of MRS as photosensors in high energy physics detectors.

The experimental results for the narrow scintillating elements with effective area about 20 cm 2 are reported. The elements were formed from the single piece of scintillator and were read out via wavelength shifting (WLS) fibers with the Metal/Resistor/Semiconductor (MRS) photodiodes on both ends of each fiber. The count rates were obtained using radioactive source 90 Sr, with threshold at about three photoelectrons in each channel and quad coincidences (double coincidences between sensors on each fiber and double coincidences between two neighboring fibers). The formation of the cells from the piece of scintillator by using grooves is discussed, and their performances were tested using the radioactive source by measuring the photomutiplier current using the same WLS fiber. Because effective cell area can be readily enlarged or reduced, this module may be used as an active element for calorimeter or muon system for the design of the future electron–positron linear collider detector. Experimental verification of the performance of the MRS photodiode in a strong magnetic field of 9 T, and the impact a magnet quench at 9.5 T are reported. The measurement method used is described. The results confirm the expectations that the MRS photodiode is insensitive to a strong magnetic field and therefore applicable to calorimetry in the presence of magnetic field. The overall result is of high importance for large multi-channel systems.

The experimental results on the performance of the Metal/Resistor/Semiconductor (MRS) photodiode in the strong magnetic field of 4.4 T, and the possible impact of the quench of the magnet at 4.5 T on sensor's operation are reported. In addition, the experimental results on the performance of the extruded scintillator and WLS fiber, and various LEDs in the magnetic fields of 1.8 and 2.3 T, respectively, are detailed. The measurement method used is being described. The results of the work agree with the expectations that the LED, MRS and scintillator are not exhibiting sensitivity to the magnetic field presence. This result is essential for the design of the future electron–positron linear collider detector.

At the future Facility for Antiproton and Ion Research in Darmstadt (FAIR) a dedicated heavy-ion experiment investigating the properties of highly Compressed Baryonic Matter is proposed (CBM). A key observable of the physics program will be a precise measurement of low-mass vector mesons in their leptonic decay channel. The essential experimental tool for identifying the decay electrons will be a gaseous RICH detector. The concept of this RICH detector will be introduced and discussed.

The MINERνA experiment at Fermilab will use a fully-active scintillator based fine grained neutrino detector and the high rate NuMI neutrino beam. MINERνA will measure low energy neutrino interaction properties and cross sections to a new level of precision. These measurements will be critical input to present and future accelerator-based neutrino oscillation experiments in this energy range.

We present results on the operation and performance characteristics of the MRS (metal/resistor/semiconductor) photodiode. These include measurements of threshold characteristics, noise frequency, dependence of signal amplitude on the applied voltage and temperature, and stability as a function of time and radiation dose. The single photoelectron separation for this photosensor is demonstrated with a light emitting diode. The response of the photodetector to light produced in a scintillator is studied with cosmic ray muons and a 106 Ru source. In addition, fiber-sensor alignment issues were evaluated. The results are promising and illustrate the potential use of MRS as photosensors in high-energy physics detectors.

The ability to distinguish between hadronic W and Z decays is one of the most challenging requirements for the future linear collider detector. Such sensitivity requires unprecedented jet energy resolution, which may be possible with energy-flow algorithms. A calorimeter that is optimized for energy-flow must have fine lateral and longitudinal segmentation. Small scintillating cells with wavelength shifting fibre readout represent an attractive basis for a digital hadron calorimeter that trades dynamic range for superior granularity, at an affordable price. We present the expected jet resolution for such a device, based on Monte Carlo simulations. Then we describe the initial prototyping studies. In particular, detailed studies are presented on cell performance under different combinations of manufacture and assembly.

The ability to distinguish physics signals that share common signatures involving multijet final states is crucial to the success of the future Linear Collider Detector (LCD). This translates into a requirement of attaining unprecedented precision in jet energy measurements. For example, to effectively separate W and Z bosons in their hadronic final states by reconstructing their invariant masses, one will require a jet energy resolution of dE/E

New projective prototypes of a scintillator/lead sandwich type sampling calorimeter Shashlik with a silicon preshower detector have been constructed and tested with an electron beam at CERN-SPS. The energy resolution is measured to be 8.7%/sqrt(E(GeV)) in stochastic term. 0.330/E(GeV) in noise term and 0.5% in constant term. The angular resolution is better than 70 mrad/sqrt(E(GeV)).

A prototype module for an International Linear Collider (ILC) detector was built, installed, and tested between 2006 and 2009 at CERN and Fermilab as part of the CALICE test beam program, in order to study the possibilities of extending energy sampling behind a hadronic calorimeter and to study the possibilities of providing muon tracking. The "tail catcher/muon tracker" (TCMT) is composed of 320 extruded scintillator strips (dimensions 1000 mm x 50 mm x 5 mm) packaged in 16 one-meter square planes interleaved between steel plates. The scintillator strips were read out with wavelength shifting fibers and silicon photomultipliers. The planes were arranged with alternating horizontal and vertical strip orientations. Data were collected for muons and pions in the energy range 6 GeV to 80 GeV. Utilizing data taken in 2006, this paper describes the design and construction of the TCMT, performance characteristics, and a beam-based evaluation of the ability of the TCMT to improve hadronic energy resolution in a prototype ILC detector. For a typical configuration of an ILC detector with a coil situated outside a calorimeter system with a thickness of 5.5 nuclear interaction lengths, a TCMT would improve relative energy resolution by 6-16 % for pions between 20 and 80 GeV., 23 pages, 18 figures, 4 tables, submitted to JINST

Proton Computed Tomography (pCT) is being developed in support of proton therapy and treatment planning. The aim of pCT, to reconstruct an accurate map of the stopping power (S.P.) in a phantom and, in the future, in patients, is being pursued with a diverse list of detector systems, using the entire arsenal of tracking and energy detectors developed for High Energy Physics (HEP). The first radiographs and 3D images are being reconstructed with prototype detectors, which will be described. Most of the existing systems are being upgraded to higher proton fluxes to reduce the scanning time.

An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. The D0 and MINOS experiments are already using extruded scintillator strips in their detectors. A new experiment at Fermilab is pursuing the use of extruded plastic scintillator. A new plastic scintillator strip is being tested and its properties characterized. The initial results are presented here.

In this article we show the latest results on the characteristics of the MRS (metal/resistor/semiconductor) photodiode. They include measurements of noise vs. threshold characteristics, noise frequency and signal amplitude dependence on the applied voltage and temperature and irradiation dose, and stability as a function of time. The photoelectron separation for this sensor is measured using a signal from a light emitting diode (LED). The response of the photodetector to light from the extruded 5 mm thick long strips of scintillator is studied using cosmic ray muons. Also, fiber-sensor alignment effects were studied. The results are promising and illustrate the potential use of MRS as photosensors in wide range of detectors.

The experimental results on the performance of the MRS (Metal/Resistor/Semiconductor) photodiode in the strong magnetic field of 4.4T, and the possible impact of the quench of the magnet at 4.5T on sensor's operation are reported.

The current conceptual design of proposed Large EMCal of ALICE at LHC is based largely on the scintillating mega-tile/fiber technology implemented in CDF Endplug upgrade project and in both barrel and endcap electromagnetic calorimeters of the STAR. The cost of scintillating material leads us to the choice of extruded polystyrene based scintillator, which is available in new FNAL-NICADD facility. Result of optical measurements, such as light yield and light yield variation, show that it is possible to use this material as active media of Large EMCal of ALICE at LHC., Comment: 6 pages, 5 figures,Prepared for XIth International Conference on Calorimetry in High Energy Physics (Calor 2004), Perugia, Italy, March 29 - April 2, 2004

Hadron calorimeter will play a key role in the success of a future e+e Linear Collider Detector (LCD). The hadron calorimeter should provide excellent energy resolution (30%E) for jets, and a fine degree of segmentation. As a possible solution, we propose the use of a Scintillating Digital Hadron Calorimeter (SDHC), which consists of millions of small plastic scintillating cells. Wave Length Shifting (WLS) fibers, embedded in the cells, will be used in the readout system. The results of studies for cell shape and thickness, shape and depth of groove for the embedded fiber, and coating materials are reported. In a cosmic-ray test, 5 mm thick cells made from BC408 scintillating plastic with WLS BCF92 1 mm outer diameter fiber, provided 30 photo-electrons measured with a 80% quantum efficiency photo-cathode.

An understanding of the costs involved in the production of plastic scintillators and the development of a less expensive material have become necessary with the prospects of building very large plastic scintillation detectors. Several factors contribute to the high cost of plastic scintillating sheets, but the principal reason is the labor-intensive nature of the manufacturing process. In order to significantly lower the costs, the current casting procedures had to be abandoned. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. This concept was tested and high quality extruded plastic scintillator was produced. The DO and MINOS experiments are already using extruded scintillator strips in their detectors. An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. This paper will discuss the characteristics of extruded plastic scintillator and its raw materials, the different manufacturing techniques and the current R&D program at Fermilab.

Shashlik calorimeter prototypes equipped with preshower detector have been tested in 3 T magnetic field with electron beam at CERN-SPS. The signal from electrons increases as much as 11% at 3 T magnetic field. No significant deterioration on the energy resolution as well as the preshower detector performance have been observed.

Purpose: To calibrate a novel protonCT scanner using polystyrene degraders of accurately known thickness and relative stopping power.Methods: A prototype protonCT scanner was constructed and installed on a horizontal proton research beam line for further study of this novel, potentially low‐dose tomographic imaging modality. The protonCT scanner registers individual protons up to a maximum rate of about 105 protons/sec, recording their entry and exit coordinates and directions with high‐resolution silicon strip detectors, as well as their residual energy by stopping them in an augmented 18‐crystal CsI calorimeter. To avoid uncertainties in the mean excitation energy (I) of water when converting energy loss to water equivalent path length (WEPL) via the Bethe‐Bloch equation, the response of the calorimeter was calibrated using polystyrene plates of known water‐equivalent thickness (WET). Stacks of polystyrene plates of variable thickness were placed between the protonCTdetectors and about 3 × 105 protons were recorded for each thickness. For each proton event, the calorimeter response was derived from the weighted sum of the response of the 18 crystals, taking into account variations in the sensitivity of each crystal. A Gaussian distribution function was fitted to the response data at each WET, and the mean of each distribution was used to establish the WEPL calibration curve. Results: For protons of 100 MeV and 200 MeV, the mean response of the calorimeter was obtained for 7–8 different WET values (including zero) and the WEPL vs. response calibration curve was fitted with a quadratic polynomial with an excellent goodness of fit. A WEPL measurement accuracy of 1 mm or better can be achieved by measuring the calorimeter response of about 150 protons Conclusions: This work is an important step towards a thorough investigation of protoncomputed tomography for therapeutic and imaging applications. Funded in part by DOD Contract W81XWH‐08‐1‐0205 and the Department of Radiation Medicine, Loma Linda University Medical Center

This paper presents the test results of a single element of a Cesium Iodide CsI(TI) crystal calorimeter matrix using proton beam energies of 35 MeV, 100 MeV and 200 MeV. The detector element was designed to comply with the demands of high energy resolution of a few percent and with a dynamic range of two orders of magnitude under a counting rate of 10 kHz per channel. The energy range investigated in the current work was an order of magnitude less than the design capability. The readout was provided by a 28 ? 28 mm2 Hamamatsu S3584-08 photodiode coupled with the crystal through a silicone optical interface. A charge-sensitive preamplifier with low noise at high photodiode capacitance was chosen. We also report on the data acquired during crystal calibration with cosmic rays, and give a description of our data acquisition (DAQ) system.

The possibility to produce a scintillator that satisfies the demands of physicists from different science areas has emerged with the installation of an extrusion line at FNAL (Fermi National Accelerator Laboratory). The extruder is the product of the fruitful collaboration between FNAL and NICADD NIU (Northern Illinois Center for Accelerator and Detector Development at Northern Illinois University). The results from light output, light attenuation length and mechanical tolerance indicate that FNAL-NICADD scintillator is of high quality. Improvements in the extrusion die will yield better scintillator profiles and decrease the time needed for initial tuning. This paper will present the characteristics of the FNAL-NICADD scintillator based on the measurements performed. They include the response to MIPs from cosmic rays for individual extruded strips and irradiation studies where extruded samples were irradiated up to 1 Mrad. We will also discuss the results achieved with a new die design. The attractive perspective of using the extruded scintillator with MRS (metal resistive semiconductor) photodetector readout will also be shown.