Table of contents

Knowledge of the material in the ATLAS inner tracking detector is crucial in understanding the reconstruction of charged-particle tracks, the performance of algorithms that identify jets containing b-hadrons and is also essential to reduce background in searches for exotic particles that can decay within the inner detector volume. Interactions of primary hadrons produced in pp collisions with the material in the inner detector are used to map the location and amount of this material. The hadronic interactions of primary particles may result in secondary vertices, which in this analysis are reconstructed by an inclusive vertex-finding algorithm. Data were collected using minimum-bias triggers by the ATLAS detector operating at the LHC during 2010 at centre-of-mass energy √s = 7 TeV, and correspond to an integrated luminosity of 19 nb⁻¹. Kinematic properties of these secondary vertices are used to study the validity of the modelling of hadronic interactions in simulation. Secondary-vertex yields are compared between data and simulation over a volume of about 0.7 m³ around the interaction point, and agreement is found within overall uncertainties.

Data on ion mobility is important to improve the performance of large volume gaseous detectors, such as the ALICE TPC or in the NEXT experiment. In the present work the method, experimental setup and results for the ion mobility measurements in Ne-N₂ mixtures are presented. The results for this mixture show the presence of two peaks for different gas ratios of Ne-N₂, low reduced electric fields, E/N, 10–20 Td (2.4–4.8 kV·cm⁻¹·bar⁻¹), low pressures 6–8 Torr (8–10.6 mbar) and at room temperature.

Future experiments in high energy and nuclear physics may require large, inexpensive calorimeters that can continue to operate after receiving doses of 50 Mrad or more. The light output of liquid scintillators suffers little degradation under irradiation. However, many challenges exist before liquids can be used in sampling calorimetry, especially regarding developing a packaging that has sufficient efficiency and uniformity of light collection, as well as suitable mechanical properties. We present the results of a study of a scintillator tile based on the EJ-309 liquid scintillator using cosmic rays and test beam on the light collection efficiency and uniformity, and some preliminary results on radiation hardness.

A versatile and reconfigurable ASIC is presented, which implements two different concepts of low level trigger (L0) for Cherenkov telescopes: the Majority trigger (sum of discriminated inputs) and the Sum trigger concept (analogue clipped sum of inputs). Up to 7 input signals can be processed following one or both of the previous trigger concepts. Each differential pair output of the discriminator is also available as a LVDS output. Differential circuitry using local feedback allows the ASIC to achieve high speed (500 MHz) while maintaining good linearity in a 1 Vpp range. Experimental results are presented. A number of prototype camera designs of the Cherenkov Telescope Array (CTA) project will use this ASIC.

A CMOS image sensor (CIS) with a large area for the high resolution X-ray imaging was designed. The sensor has an active area of 125 × 125 mm² comprised with 2304 × 2304 pixels and a pixel size of 55 × 55 μm². First batch samples were fabricated by using an 8 inch silicon CMOS image sensor process with a stitching method. In order to evaluate the performance of the first batch samples, the electro-optical test and the X-ray test after coupling with an image intensifier screen were performed. The primary results showed that the performance of the manufactured sensors was limited by a large stray capacitance from the long path length between the analog multiplexer on the chip and the bank ADC on the data acquisition board. The measured speed and dynamic range were limited up to 12 frame per sec and 55 dB respectively, but other parameters such as the MTF, NNPS and DQE showed a good result as designed. Based on this study, the new X-ray CIS with ∼ 50 μm pitch and ∼ 150 cm² active area are going to be designed for the high resolution X-ray NDT equipment for semiconductor and PCB inspections etc.

The photon detection efficiency of two sets of R10560-100-20 superbialkali photomultiplier tubes from Hamamatsu were measured between 200 nm and 750 nm to quantify a possible degradation of the photocathode sensitivity after four years of operation in the cameras of the VERITAS Cherenkov telescopes. A sample of 20 photomultiplier tubes, which was removed from the telescopes was compared with a sample of 20 spare photomultiplier tubes, which had been kept in storage. It is found that the average photocathode sensitivity marginally increased below 300 nm and dropped by 10% to 30% above 500 nm. The average photocathode sensitivity folded with the Cherenkov spectrum emitted by particles in air showers, however, reveals a consistent detection yield of 18.9 ± 0.2% and 19.1 ± 0.2% for the sample removed from the telescope and the spare sample, respectively.

In small animal and organ dedicated PET scanners, the knowledge of depth of interaction (DOI) of the gamma ray along the main axis of the scintillator is a fundamental information in order to avoid parallax error and to achieve high performances in terms of spatial resolution. Recently we developed a new method to obtain the DOI function for a single side readout PET module, recirculating the scintillation light in the matrix by means of a mirror placed on top of the module. In a complete PET scanner, periodical DOI calibrations have to be performed to prevent time dependent miscalibrations and performance degradations. The current DOI calibration relies on a coincidence system between the module and an external scintillator to provide a priori the DOI information and it is clearly not feasible in a real system without unpractical disassemblies of the scanner. In this paper we develop instead a fast and precise calibration method based on uniform irradiation of the scintillators. Three irradiation modalities are presented, in particular one where the source is placed on top of the module, one with the source placed on one side of the module and one that exploits the internal radioactivity of the scintillator. The three different procedures are evaluated and the calibration method is validated by comparing the information provided by the coincidence setup.

The ATLAS Roman Pot system is designed to determine the total proton-proton cross section as well as the luminosity at the Large Hadron Collider (LHC) by measuring elastic proton scattering at very small angles. The system is made of four Roman Pot stations, located in the LHC tunnel in a distance of about 240 m at both sides of the ATLAS interaction point. Each station is equipped with tracking detectors, inserted in Roman Pots which approach the LHC beams vertically. The tracking detectors consist of multi-layer scintillating fibre structures read out by Multi-Anode-Photo-Multipliers.

A Time Projection Chamber (TPC) is an ideal device for three-dimensional tracking. It is used in many experiments including ALICE at LHC. The choice of the gas mixture is crucial for this type detector performance. For the operation of the TPC at ALICE, Ne–CO₂–N₂ was chosen. Because of the relatively low primary ionisation of Ne, the readout chambers have to be operated at high gas gains near 10⁴. Therefore gas gain factor has been measured and calculated for this mixture. The Diethorn, Williams and Sara and of Aoyama models of the first Townsend coefficient have been used to determine the basic gas properties. Photon feedback parameters and Penning transfer rates have been also determined.

The DANSS project is aimed at creating a relatively compact neutrino spectrometer which does not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial power reactor. As a result, it is expected that high neutrino flux would provide about 15,000 IBD interactions per day in the detector with a sensitive volume of 1 m³. High segmentation of the plastic scintillator will allow to suppress a background down to a ∼1% level. Numerous tests performed with a simplified pilot prototype DANSSino under a 3 GW_th reactor of the Kalinin NPP have demonstrated operability of the chosen design. The DANSS detector surrounded with a composite shield is movable by means of a special lifting gear, varying the distance to the reactor core in a range from 10 m to 12 m. Due to this feature, it could be used not only for the reactor monitoring, but also for fundamental research including short-range neutrino oscillations to the sterile state. Supposing one-year measurement, the sensitivity to the oscillation parameters is expected to reach a level of sin²(2θ_new) ∼ 5 × 10⁻³ with Δ m² ⊂ (0.02–5.0) eV².

This work presents a study of the factors contributing to the Photo-Detection Efficiency of Silicon Photomultipliers (SiPMs): Quantum Efficiency, Triggering Probability and Fill Factor. Two different SiPM High-Density technologies are tested, NUV-HD, based on n-on-p junction, and RGB-HD, based on p-on-n junction, developed at FBK, Trento. The quantum efficiency was measured on photodiodes produced along with the SiPMs. The triggering probability, as a function of wavelength and bias voltage, was measured on circular Single Photon Avalanche Diodes (SPADs) with 100% fill factor. Square SPADs, having the same layout of single SiPM cells, were studied to measure the effective fill factor and compare it to the nominal value. The comparison of the circular and square SPADs allows to get the transition region size between the effective active area of the cell and the one defined by the layout.

We describe and report the status of a neutrino-triggered program in IceCube that generates real-time alerts for gamma-ray follow-up observations by atmospheric-Cherenkov telescopes (MAGIC and VERITAS). While IceCube is capable of monitoring the whole sky continuously, high-energy gamma-ray telescopes have restricted fields of view and in general are unlikely to be observing a potential neutrino-flaring source at the time such neutrinos are recorded. The use of neutrino-triggered alerts thus aims at increasing the availability of simultaneous multi-messenger data during potential neutrino flaring activity, which can increase the discovery potential and constrain the phenomenological interpretation of the high-energy emission of selected source classes (e.g. blazars). The requirements of a fast and stable online analysis of potential neutrino signals and its operation are presented, along with first results of the program operating between 14 March 2012 and 31 December 2015.

The CaLIPSO project aims to develop a high precision brain-scanning PET device with time-of-flight capability. The proposed device uses an innovative liquid, the TriMethyl Bismuth, as the detection medium. It detects simultaneously the ionization and optical signals from the 511 keV gamma conversion. In this paper we present the design, the Monte Carlo simulation, and the tests results for the CaLIPSO optical prototype. In this prototype we demonstrated the ability to detect efficiently the low number of the optical photons produced by the relativistic electron from the gamma conversion through the Cherenkov effect. The time resolution of the current prototype is limited by the moderate time transition spread of the PMT, but should be improved to the level better than 100 ps (FWHM) by using micro-channel-plate PMT according to the Geant 4 simulation.

We present measurements of high-energy ions with the Timpepix3, a compact, single-layer pixelated radiation detector, developed by the Medipix3 Collaboration. We discuss some novel types of information that can be gleaned from the time-of-arrival information provided by the detector. We demonstrate precise energy measurements for ions with moderate stopping powers. We compare data with predictions from Landau-Vavilov theory, and find good agreement, particularly at high incidence angles, relative to the detector surface normal. Higher stopping powers pose a problem with the detector, as it is unable to measure energy deposits larger than about 500 keV per pixel.

Lately, cancer has been treated using high-energy radiation, and this requires highly reliable treatment plans. Therefore, a dosimeter with excellent performance, which is capable of precise dose measurement, is critical. In current clinical practices, an ionization chamber and diode utilizing the ionization reaction mechanism are widely used. Several studies have been carried out to determine optimal materials for the detector in a dosimeter to enable diagnostic imaging. Recently, studies with lead monoxide, which was shown to have low drift current and high resolving power at a high bias, were reported with the dosimeter exhibiting a fast response time against incident photons. This research aims to investigate the feasibility of a lead monoxide-based dosimeter for QA (quality assurance) in radiotherapy. In this paper, we report that the manufactured dosimeter shows similar linearity to a silicon diode and demonstrates similar characteristics in terms of PDD (percent depth dose) results for the thimble ionization chamber. Based on these results, it is demonstrated that the lead monoxide-based dosimeter complies with radiotherapy QA requirements, namely rapid response time, dose linearity, dose rate independence. Thus, we expect the lead monoxide-based dosimeter to be used commercially in the future.

Bonner Spheres have been used widely for the measurement of neutron spectra with neutron energies ranged from thermal up to at least 20 MeV . A Bonner Sphere neutron spectrometer (BSS) was developed by extending a Berthold LB 6411 neutron-dose-rate meter. The BSS consists of a ³He thermal-neutron detector with integrated electronics, a set of eight polyethylene spherical shells and two optional lead shells of various sizes. The response matrix of the BSS was calculated with GEANT4 Monte Carlo simulation. The BSS had a calibration uncertainty of ± 8.6% and a detector background rate of (1.57 ± 0.04) × 10⁻³ s⁻¹. A spectral unfolding code NSUGA was developed. The NSUGA code utilizes genetic algorithms and has been shown to perform well in the absence of a priori information.

Photodetectors with excellent time resolution are becoming increasingly important in many applications in medicine, high energy- and nuclear physics applications, biology, and material science. Silicon photomultipliers (SiPM) are a novel class of solid-state photodetectors with good timing properties. While the time resolution of analog SiPMs has been analyzed by many groups, the time resolution of the digital photon counter (DPC) developed by Philips has not yet been fully characterised. Here, the timing capabilities of the DPC are studied using a femtosecond laser. The time resolution is determined for complete dies, single pixels, and individual single photon avalanche diodes (SPADs). The measurements cover a broad dynamic range, from intense illumination down to the single-photon level, and were performed at various temperatures between 0°C and 20°C. The measured single photon time resolution (SPTR) ranges from 101 ps FWHM for the DPC3200 sensor pixel to 247 ps FWHM for the DPC6400 sensor die. An extensive study of the single-SPAD time resolution, ranging from single photon to very high laser intensities (∼1000 photons per pulse), yielded a time resolution of 48 ps FWHM at the single-photon level.

In the readout electronics of the Water Cerenkov Detector Array (WCDA) in the Large High Altitude Air Shower Observatory (LHAASO), both high-resolution charge and time measurement are required over a dynamic range from 1 photoelectron (P.E.) to 4000 P.E. for the PMT signal readout. In this paper, we present our work on the design of time discrimination circuits in LHAASO WCDA, especially on improvement to reduce the circuit dead time. Several approaches were studied through analysis and simulations, and actual circuits were designed and tested in the laboratory to evaluate the performance. Test results indicate that a time resolution better than 500 ps RMS is achieved in the whole large dynamic range, and the circuit dead time is successfully reduced to less than 200 ns.

In this report we discuss static and time dependent electric fields in detector geometries with an arbitrary number of parallel layers of a given permittivity and weak conductivity. We derive the Green's functions i.e. the field of a point charge, as well as the weighting fields for readout pads and readout strips in these geometries. The effect of `bulk' resistivity on electric fields and signals is investigated. The spreading of charge on thin resistive layers is also discussed in detail, and the conditions for allowing the effect to be described by the diffusion equation is discussed. We apply the results to derive fields and induced signals in Resistive Plate Chambers, MICROMEGAS detectors including resistive layers for charge spreading and discharge protection as well as detectors using resistive charge division readout like the MicroCAT detector. We also discuss in detail how resistive layers affect signal shapes and increase crosstalk between readout electrodes.

The New Iram Kid Arrays-2 (NIKA2) instrument has recently been installed at the IRAM 30 m telescope. NIKA2 is a state-of-art instrument dedicated to mm-wave astronomy using microwave kinetic inductance detectors (KID) as sensors. The three arrays installed in the camera, two at 1.25 mm and one at 2.05 mm, feature a total of 3300 KIDs. To instrument these large array of detectors, a specifically designed electronics, composed of 20 readout boards and hosted in three microTCA crates, has been developed. The implemented solution and the achieved performances are presented in this paper. We find that multiplexing factors of up to 400 detectors per board can be achieved with homogeneous performance across boards in real observing conditions, and a factor of more than 3 decrease in volume with respect to previous generations.

The ATLAS New Small Wheels will be the first major upgrade to an LHC experiment utilizing the Micromegas technology. With an active detection area of 1280 m² and comprising more than two million channels it is the largest and probably most ambitious system of Micro Pattern Gaseous Detectors (MPGDs) currently under construction. The eponymous component of the Micromegas technology, the micromesh, is the detector's most precise component. Although a wide range of meshes, mesh geometries and parameters can be used to build an operational Micromegas, its properties can affect a range of detector qualities, such as reconstruction efficiency, timing and energy resolution. Conversely, the correct choice of this component will permit a wider range in operation parameters and optimize the detector performance.

A multilayer stacked X-ray camera concept is described. This type of technology is called `4H' X-ray cameras, where 4H stands for high-Z (Z>30) sensor, high-resolution (less than 300 micron pixel pitch), high-speed (above 100 MHz), and high-energy (above 30 keV in photon energy). The components of the technology, similar to the popular two-dimensional (2D) hybrid pixelated array detectors, consists of GaAs:Cr sensors bonded to high-speed ASICs. 4H cameras based on GaAs also use integration mode of X-ray detection. The number of layers, on the order of ten, is smaller than an earlier configuration for single-photon-counting (SPC) mode of detection [1]. High-speed ASIC based on modification to the ePix family of ASIC is discussed. Applications in X-ray free electron lasers (XFELs), synchrotrons, medicine and non-destructive testing are possible.

The Multi-gap Resistive Plate Chamber (MRPC) is a new type of gas detector developed in recent years. It has excellent time resolution (better than 100 ps) and high efficiency (higher than 95%). This detector has been used to construct large-area time-of-flight (TOF) system in many nuclear and particle physics experiments. However, as a type of gaseous detector, the aging of the gas mixture under long-time exposure to ionizing radiation cannot be neglected. With the increase of accelerator luminosity, impurities in the gas mixture can be potentially dangerous for long-term operation of the MRPC. This has been observed in some experiments, for example with the RHIC-STAR muon telescope detector. The CBM-TOF, used for hadron identification, is proposed to be assembled with MRPCs. These counters have to stand particle fluxes as high as 25 kHz/cm², and thus the gas pollution is a critical aspect to be studied. In order to better understand the gas quality's impact on the MRPC performance, a two-dimensional simulation based on the SIMPLE algorithm is carried out to imitate the distribution of impurities in a MRPC gas box. The preliminary results show that gas pollution grows stronger with the increase of the gas-flowing volume. In addition, we conducted a series of experiments with a 50 × 50 cm², 8-gap MRPC prototype. The results match the simulation quite well. Gas pollution indeed has a severe impact on the MRPC performance, and further study can be very useful to reduce gas aging effects in high-luminosity experiments.

The full exploitation of the physics potential of the high luminosity LHC is a big challenge that requires new instrumentation and innovative solutions. We present here a conceptual design and simulation studies of a fast timing pixel detector with embedded real-time tracking capabilities. The system is conceived to operate at 40 MHz event rate and to reconstruct tracks in real-time, using precise space and time 4D information of the hit, for fast trigger decisions. This work is part of an R&D project aimed at building an innovative tracking detector with superior time (10 ps) and position (10 μm) resolutions to be used in very harsh radiation environments, for the ultimate flavour physics experiment at the high luminosity phase of the LHC.

The physics aims at the future CLIC high-energy linear e+e- collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few μm, ultra-low mass (∼ 0.2%X₀ per layer for the vertex region and ∼ 1%X₀ per layer for the outer tracker), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ∼ 10 ns time stamping capabilities. A highly granular all-silicon vertex and tracking detector system is under development, following an integrated approach addressing simultaneously the physics requirements and engineering constraints. For the vertex-detector region, hybrid pixel detectors with small pitch (25 μm) and analog readout are explored. For the outer tracking region, both hybrid concepts and fully integrated CMOS sensors are under consideration. The feasibility of ultra-thin sensor layers is validated with Timepix3 readout ASICs bump bonded to active edge planar sensors with 50 μm to 150 μm thickness. Prototypes of CLICpix readout ASICs implemented in 6525 nm CMOS technology with 25 μm pixel pitch have been produced. Hybridisation concepts have been developed for interconnecting these chips either through capacitive coupling to active HV-CMOS sensors or through bump-bonding to planar sensors. Recent R&D achievements include results from beam tests with all types of hybrid assemblies. Simulations based on Geant4 and TCAD are used to validate the experimental results and to assess and optimise the performance of various detector designs.

This paper presents the first pixel detector realized using the BCD8 technology of STMicroelectronics. The BCD8 is a 160 nm process with bipolar, CMOS and DMOS devices; mainly targeted for an automotive application. The silicon particle detector is realized as a pixel sensor diode with a dimension of 250 × 50 μm². To support the signal sensitivity of pixel diode, the circuit simulations have been performed with a substrate voltage of 50 V. The analog signal processing circuitry and the digital operation of the circuit is designed with the supply voltage of 1.8 V. Moreover, an analog processing part of the pixel detector circuit is confined in a unit pixel (diode sensor) to achieve 100 % fill factor. As a first phase of the design, an array of 8 pixels and 4 passive diodes have been designed and measured experimentally. The entire analog circuitry including passive diodes is implemented in a single chip. This chip has been tested experimentally with 70 V voltage capability, to evaluate its suitability. The sensor on a 125 Ωcm resistivity substrate has been characterized in the laboratory. The CMOS sensor realizes a depleted region of several tens of micrometer. The characterization shows a uniform breakdown at 70 V before irradiation and an approximate capacitance of 80 fF at 50 V of reverse bias voltage. The response to ionizing radiation is tested using radioactive sources and an X-ray tube.

We constructed a new time-of-flight (TOF) detector consisting of resistive plate chambers (RPCs) to measure particle energy in the BGOegg experiment. The BGOegg-RPC has a unique feature which enables us to cover a large area with a small number of readout channels. For this purpose, we developed the RPC with a strip size of 2.5 cm × 100 cm. The BGOegg-RPC covers an area of 320 cm × 200 cm with only 256 channels of readout electronics. In case of large readout RPCs, an originated signal is distorted and dispersed during propagation. In addition, there happens a signal reflection at the end of the strip. Although we designed the BGOegg-RPC and front-end electronics with minimized signal reflection, a small reflection still remained, deteriorating the resulting time resolution. After establishing calibration and correction methods to improve the performance of the BGOegg-RPC, we obtained the time resolution of σ ∼ 60 ps around the central region of strips.

ATLAS is a multipurpose experiment at the LHC proton-proton collider. Its physics goals require an unbiased and high resolution measurement of the charged particle kinematic parameters. These critically depend on the layout and performance of the tracking system and the quality of the alignment of its components. For the LHC Run 2, the system has been upgraded with the installation of a new pixel layer, the Insertable B-layer (IBL) . ATLAS Inner Detector alignment framework has been adapted and upgraded to correct very short time scale movements of the sub-detectors. In particular, a mechanical distortion of the IBL staves up to 20 μm and a vertical displacement of the Pixel detector of ∼ 6 μm have been observed during data-taking. The techniques used to correct for these effects and to match the required Inner Detector performance will be presented.

The presented work is related to the Gas Electron Multiplier (GEM) detector soft X-ray spectroscopy system for tokamak applications. The used GEM detector has one-dimensional, 128 channel readout structure. The channels are connected to the radiation-hard electronics with configurable analog stage and fast ADCs, supporting speeds of 125 MSPS for each channel. The digitalized data is sent directly to the FPGAs using fast serial links. The preprocessing algorithms are implemented in the FPGAs, with the data buffering made in the on-board 2Gb DDR3 memory chips. After the algorithmic stage, the data is sent to the Intel Xeon-based PC for further postprocessing using PCI-Express link Gen 2. For connection of multiple FPGAs, PCI-Express switch 8-to-1 was designed. The whole system can support up to 2048 analog channels. The scope of the work is an FPGA-based implementation of the recorder of the raw signal from GEM detector. Since the system will work in a very challenging environment (neutron radiation, intense electro-magnetic fields), the registered signals from the GEM detector can be corrupted. In the case of the very intense hot plasma radiation (e.g. laser generated plasma), the registered signals can overlap. Therefore, it is valuable to register the raw signals from the GEM detector with high number of events during soft X-ray radiation. The signal analysis will have the direct impact on the implementation of photon energy computation algorithms. As the result, the system will produce energy spectra and topological distribution of soft X-ray radiation. The advanced software was developed in order to perform complex system startup and monitoring of hardware units. Using the array of two one-dimensional GEM detectors it will be possible to perform tomographic reconstruction of plasma impurities radiation in the SXR region.

We report on the results of a systematic study for the charge distribution dependency of CMS Resistive Plate Chamber (RPC) on the gap thickness. Prototypes of the double-gap RPCs with six different gap thicknesses ranging from 1.0 to 2.0 mm in 0.2 mm steps were built with 2 mm-thick phenolic high-pressure-laminated (HPL) plates. The efficiencies of the six gaps were measured as a function of the effective high voltages. We report that the strength of the electric field of the gap decreased as the gap thickness increased. The charge distribution in the six gaps was measured, and the space charge effect is seen in the charge distribution at high voltages near 95% efficiency. The logistic function is used to fit the charge distribution data, and smaller charges than charges within the current 2.0 mm gap are produced within smaller gas gaps. The digitization threshold should also be lowered to utilize these smaller charges.

This work is concerned with the design of a readout chip for application to experiments at the next generation X-ray Free Electron Lasers (FEL). The ASIC, named PixFEL Matrix (PFM2), has been designed in a 65 nm CMOS technology and consists of 32 × 32 pixels. Each cell covers an area of 110 × 110 μm² and includes a low-noise charge sensitive amplifier (CSA) with dynamic signal compression, a time-variant shaper used to process the preamplifier output signal, a 10-bit successive approximation register (SAR) analog-to-digital converter (ADC) and digital circuitry for channel control and data readout. Two different solutions for the readout channel, based on different versions of the time-variant filter, have been integrated in the chip. Both solutions can be operated in such a way to cope with the high frame rate (exceeding 1 MHz) foreseen for future X-ray FEL machines. The ASIC will be bump bonded to a slim/active edge pixel sensor to form the first demonstrator for the PixFEL X-ray imager. This work has been carried out in the frame of the PixFEL project funded by Istituto Nazionale di Fisica Nucleare (INFN), Italy.

With the ability to attribute signatures of ionising radiation to certain particle types, pixel detectors offer a unique advantage over the traditional use of Geiger-Müller tubes also in educational settings. We demonstrate in this work how a Timepix readout chip combined with a standard 300μm pixelated silicon sensor can be used to visualise radioactivity in real-time and by means of augmented reality. The chip family is the result of technology transfer from High Energy Physics at CERN and facilitated by the Medipix Collaboration. This article summarises the development of a prototype based on an iPad mini and open source software detailed in ref. [1]. Appropriate experimental activities that explore natural radioactivity and everyday objects are given to demonstrate the use of this new tool in educational settings.

The proposed INO-ICAL detector [1] is going to be instrumented with 28800 RPCs (Resistive Plate Chamber). These RPCs (2 × 2 m² size) will consist of two glass electrodes separated by 2 mm and will use a gas mixture of Freon R134a, isobutane and sulphur hexafluoride (in the ratio of 95.3:4.5:0.2). An Open Ended System (OES), in which the gas mixture is vented to the atmosphere after a single passage through the detector, is most commonly used for small detector setups. However, OES cannot be used with the INO-ICAL detector due to reasons of cost and pollution. It is necessary, therefore, to recirculate the gas mixture in a closed loop. In a Closed Loop gas System (CLS) [2] the gas mixture is purified and recirculated after flowing through the RPC. The impurities which get accumulated in the gas mixture due to leaks or formation of radicals are removed by suitable filters. The Open Loop System (OLS) [3] is based on the separation and recovery of major gas components after passage of the gas mixture through the RPCs. and has the advantage that it does not need filters for removal of impurities. However a CLS is found to be more efficient than OLS in the recovery of gases in the mixture. In this paper we discuss centrifugal separation [4] as a technique to extract major gas constituents and use this technique to improve the efficiency of OLS. Results from preliminary trial runs are reported.

In this paper an innovative space metrology system which objective is to measure the mutual arrangement between two spacecrafts is descripted. It is a simple and robust system that makes possible relative attitude measurements between 2 satellites in formation flying with coarse and fine accuracies. Generally, in formation flying mission it's necessary to have a satellite attitude control whose accuracy depends on their relative distance. The proposed metrology is based on an innovative optical projective system embedded on satellite 1 and a target composed by several light sources mounted on satellite 2. Optical system concurrently projects on a CCD two images of the target and from relative position of the light sources on the CCD image plane it's possible to detect position and attitude of the S2. Basic element of innovation of this versatile metrology concept is the possibility to work on a very large S/Cs range distance (∼10 m–15 km) and to determinate the relative attitude and position of two spacecrafts on all six degree of freedom in a very simple and fast way.

The MuPix7 chip is a monolithic HV-CMOS pixel chip, thinned down to 50 μm. It provides continuous self-triggered, non-shuttered readout at rates up to 30,Mhits/chip of 3 × 3 mm² active area and a pixel size of 103 × 80 μm². The hit efficiency depends on the chosen working point. Settings with a power consumption of 300 mW/cm² allow for a hit efficiency > 99.5%. A time resolution of 14.2 ns (Gaussian sigma) is achieved. Latest results from 2016 test beam campaigns are shown.

The ATLAS Pixel Insertable B-Layer (IBL) detector was installed into the ATLAS experiment in 2014 and has been in operation since 2015. During the first year of data taking, an increase of the low-voltage current of the FE-I4 chip was measured. This increase was traced back to radiation damage in the chip. The dependence of the current from the Total Ionising Dose (TID) and temperature has been tested with X-ray irradiations. This paper presents the measurement results and gives a parameterisation of the leakage current and detector operation guidelines.

The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) detector will be installed in Roman pots (RP) positioned on either side of CMS, at about 210 m from the interaction point. This detector will measure leading protons, allowing detailed studies of diffractive physics and central exclusive production in standard LHC running conditions. An essential component of the CT-PPS apparatus is the tracking system, which consists of two detector stations per arm equipped with six 3D silicon pixel-sensor modules, each read out by six PSI46dig chips. The front-end electronics has been designed to fulfill the mechanical constraints of the RP and to be compatible as much as possible with the readout chain of the CMS pixel detector. The tracking system is currently under construction and will be installed by the end of 2016. In this contribution the final design and the expected performance of the CT-PPS tracking system is presented. A summary of the studies performed, before and after irradiation, on the 3D detectors produced for CT-PPS is given.

A pilot experimental set up of the India Based Neutrino Observatory's ICAL detector has been operational for the last 4 years at TIFR, Mumbai. Twelve glass RPC detectors of size 2 × 2 m², with a gas gap of 2 mm are under test in a closed loop gas recirculation system. These RPCs are continuously purged individually, with a gas mixture of R134a (C₂H₂F₄), isobutane (iC₄H₁₀) and sulphur hexafluoride (SF₆) at a steady rate of 360 ml/h to maintain about one volume change a day. To economize gas mixture consumption and to reduce the effluents from being released into the atmosphere, a closed loop system has been designed, fabricated and installed at TIFR. The pressure and flow rate in the loop is controlled by mass flow controllers and pressure transmitters. The performance and integrity of RPCs in the pilot experimental set up is being monitored to assess the effect of periodic fluctuation and transients in atmospheric pressure and temperature, room pressure variation, flow pulsations, uniformity of gas distribution and power failures. The capability of closed loop gas recirculation system to respond to these changes is also studied. The conclusions from the above experiment are presented. The validations of the first design considerations and subsequent modifications have provided improved guidelines for the future design of the engineering module gas system.

The upgrade of the ALICE vertex detector, the Inner Tracking System (ITS), is scheduled to be installed during the next long shutdown period (2019-2020) of the CERN Large Hadron Collider (LHC) . The current ITS will be replaced by seven concentric layers of Monolithic Active Pixel Sensors (MAPS) with total active surface of ∼10 m², thus making ALICE the first LHC experiment implementing MAPS detector technology on a large scale. The ALPIDE chip, based on TowerJazz 180 nm CMOS Imaging Process, is being developed for this purpose. A particular process feature, the deep p-well, is exploited so the full CMOS logic can be implemented over the active sensor area without impinging on the deposited charge collection. ALPIDE is implemented on silicon wafers with a high resistivity epitaxial layer. A single chip measures 15 mm by 30 mm and contains half a million pixels distributed in 512 rows and 1024 columns. In-pixel circuitry features amplification, shaping, discrimination and multi-event buffering. The readout is hit driven i.e. only addresses of hit pixels are sent to the periphery. The upgrade of the ITS presents two different sets of requirements for sensors of the inner and of the outer layers due to the significantly different track density, radiation level and active detector surface. The ALPIDE chip fulfils the stringent requirements in both cases. The detection efficiency is higher than 99%, fake-hit probability is orders of magnitude lower than the required 10⁻⁶ and spatial resolution within the required 5 μm. This performance is to be maintained even after a total ionising does (TID) of 2.7 Mrad and a non-ionising energy loss (NIEL) fluence of 1.7 × 10¹³ 1 MeV n_eq/cm², which is above what is expected during the detector lifetime. Readout rate of 100 kHz is provided and the power density of ALPIDE is less than 40 mW/cm². This contribution will provide a summary of the ALPIDE features and main test results.

3D silicon pixel detectors have been investigated as radiation-hard candidates for the innermost layers of the HL-LHC upgrade of the ATLAS pixel detector. 3D detectors are already in use today in the ATLAS IBL and AFP experiments. These are based on 50 × 250 μm² large pixels connected to the FE-I4 readout chip. Detectors of this generation were irradiated to HL-LHC fluences and demonstrated excellent radiation hardness with operational voltages as low as 180 V and power dissipation of 12–15 mW/cm² at a fluence of about 10¹⁶ n_eq/cm², measured at -25°C. Moreover, to cope with the higher occupancies expected at the HL-LHC, a first run of a new generation of 3D detectors designed for the HL-LHC was produced at CNM with small pixel sizes of 50 × 50 and 25 × 100 μm², matched to the FE-I4 chip. They demonstrated a good performance in the laboratory and in beam tests with hit efficiencies of about 97% at already 1–2 V before irradiation.

In Low Earth Orbit (LEO) in space electronic equipment aboard satellites and space crews are exposed to high ionizing radiation levels. To reduce radiation damage and the exposure of astronauts, to improve shielding and to assess dose levels, it is valuable to know the composition of the radiation fields and particle directions. The presented measurements are carried out with the Space Application of Timepix Radiation Monitor (SATRAM). There, a Timepix detector (300 μm thick silicon sensor, pixel pitch 55 μm, 256 × 256 pixels) is attached to the Proba-V, an earth observing satellite of the European Space Agency (ESA). The Timepix detector's capability was used to determine the directions of energetic charged particles and their corresponding stopping powers. Data are continuously taken at an altitude of 820 km on a sun-synchronous orbit. The particles pitch angles with respect to the sensor layer were measured and converted to an Earth Centred Earth Fixed (ECEF) coordinate system. Deviations from an isotropic field are extracted by normalization of the observed angular distributions by a Geant4 Monte Carlo simulation —taking the systematics of the reconstruction algorithm and the pixelation into account.

In this work we have focused on detection of thermal neutrons generated by ²³⁹Pu–Be isotopic neutron source. A high quality liquid phase epitaxial layer of 4H-SiC was used as a detection region. The thickness of the layer was 70 μ m and the diameter of circular Au/Ni Schottky contact was 4.5 mm. Around the Schottky contact two guard rings were created. The detector structure was first examined as a detector of protons and alpha particles for energy calibration. Monoenergetic protons of energies from 300 keV up to 1.9 MeV were used for detector energy calibration and a good linearity was observed. The energy resolution of 35 keV was obtained for 1.9 MeV protons. The ⁶LiF conversion layer was applied on the detector Schottky contact. In the experiment we used different thicknesses of conversion layers from 5 μ m up to 35 μ m. Measured detected spectra show two parts corresponding to alpha particles detection in lower energy channels and ³H in higher energy channels. We have also performed simulations of thermal neutron detection using MCNPX (Monte Carlo N-particle eXtended) code. The detection efficiency and the detector response to thermal neutrons was calculated with respect to the ⁶LiF layer thickness. The detection efficiency calculation is found to be in good agreement with the experiment.

For the purpose of designing an x-ray detector system for cargo container inspection, we have investigated the energy-absorption signal and noise in CdWO₄ detectors for megavoltage x-ray photons. We describe the signal and noise measures, such as quantum efficiency, average energy absorption, Swank noise factor, and detective quantum efficiency (DQE), in terms of energy moments of absorbed energy distributions (AEDs) in a detector. The AED is determined by using a Monte Carlo simulation. The results show that the signal-related measures increase with detector thickness. However, the improvement of Swank noise factor with increasing thickness is weak, and this energy-absorption noise characteristic dominates the DQE performance. The energy-absorption noise mainly limits the signal-to-noise performance of CdWO₄ detectors operated at megavoltage x-ray beam.

The PERCIVAL (Pixelated Energy Resolving CMOS Imager, Versatile And Large) soft X-ray 2D imaging detector is based on stitched, wafer-scale sensors possessing a thick epi-layer, which together with back-thinning and back-side illumination yields elevated quantum efficiency in the photon energy range of 125–1000 eV. Main application fields of PERCIVAL are foreseen in photon science with FELs and synchrotron radiation. This requires high dynamic range up to 10⁵ ph @ 250 eV paired with single photon sensitivity with high confidence at moderate frame rates in the range of 10–120 Hz. These figures imply the availability of dynamic gain switching on a pixel-by-pixel basis and a highly parallel, low noise analog and digital readout, which has been realized in the PERCIVAL sensor layout. Different aspects of the detector performance have been assessed using prototype sensors with different pixel and ADC types. This work will report on the recent test results performed on the newest chip prototypes with the improved pixel and ADC architecture. For the target frame rates in the 10–120 Hz range an average noise floor of 14e⁻ has been determined, indicating the ability of detecting single photons with energies above 250 eV. Owing to the successfully implemented adaptive 3-stage multiple-gain switching, the integrated charge level exceeds 4 · 10⁶ e⁻ or 57000 X-ray photons at 250 eV per frame at 120 Hz. For all gains the noise level remains below the Poisson limit also in high-flux conditions. Additionally, a short overview over the updates on an oncoming 2 Mpixel (P2M) detector system (expected at the end of 2016) will be reported.

AGIPD (adaptive gain integrating pixel detector) is a detector system developed for the European XFEL (XFEL.EU), which is currently being constructed in Hamburg, Germany. The XFEL.EU will operate with bunch trains at a repetition rate of 10 Hz. Each train consists of 2700 bunches with a temporal separation of 220 ns corresponding to a rate of 4.5 MHz. Each photon pulse has a duration of < 100 fs (rms) and contains up to 10¹² photons in an energy range between 0.25 and 25 keV . In order to cope with the large dynamic range, the first stage of each bump-bonded AGIPD ASIC is a charge sensitive preamplifier with three different gain settings that are dynamically switched during the charge integration. Dynamic gain switching allows single photon resolution in the high gain stage and can cover a dynamic range of 10⁴ × 12.4 keV photons in the low gain stage. The burst structure of the bunch trains forces to have an intermediate in-pixel storage of the signals. The full scale chip has 352 in-pixel storage cells inside the pixel area of 200 × 200 μm². This contribution will report on the measurements done with the new calibration circuitry of the AGIPD1.1 chip (without sensor). These results will be compared with the old version of the chip (AGIPD1.0). A new calibration method (that is not AGIPD specific) will also be shown.

Each front-end readout ASIC for the High-Energy Physics experiments requires robust and effective hit data streaming and control mechanism. A new STS-XYTER2 full-size prototype chip for the Silicon Tracking System and Muon Chamber detectors in the Compressed Baryonic Matter experiment at Facility for Antiproton and Ion Research (FAIR, Germany) is a 128-channel time and amplitude measuring solution for silicon microstrip and gas detectors. It operates at 250 kHit/s/channel hit rate, each hit producing 27 bits of information (5-bit amplitude, 14-bit timestamp, position and diagnostics data). The chip back-end implements fast front-end channel read-out, timestamp-wise hit sorting, and data streaming via a scalable interface implementing the dedicated protocol (STS-HCTSP) for chip control and hit transfer with data bandwidth from 9.7 MHit/s up to 47 MHit/s. It also includes multiple options for link diagnostics, failure detection, and throttling features. The back-end is designed to operate with the data acquisition architecture based on the CERN GBTx transceivers. This paper presents the details of the back-end and interface design and its implementation in the UMC 180 nm CMOS process.

Hybrid foams are materials formed by a core from a standard open cell metal foam that is during the process of electrodeposition coated by a thin layer of different nanocrystalline metals. The material properties of the base metal foam are in this way modified resulting in higher plateau stress and, more importantly, by introduction of strain-rate dependence to its deformation response. In this paper, we used time-lapse X-ray micro-tomography for the mechanical characterization of Ni/Al hybrid foams (aluminium open cell foams with nickel coating layer). To fully understand the effects of the coating layer on the material's effective properties, we compared the compressive response of the base uncoated foam to the response of the material with coating thickness of 50 and 75 μm. Digital volume correlation (DVC) was applied to obtain volumetric strain fields of the deforming micro-structure up to the densification region of the deforming cellular structure. The analysis was performed as a compressive mechanical test with simultaneous observation using X-ray radiography and tomography. A custom design experimental device was used for compression of the foam specimens in several deformation states directly in the X-ray setup. Planar X-ray images were taken during the loading phases and a X-ray tomography was performed at the end of each loading phase (up to engineering strain 22%). The samples were irradiated using micro-focus reflection type X-ray tube and images were taken using a large area flat panel detector. Tomography reconstructions were used for an identification of a strain distribution in the foam using digital volumetric correlation. A comparison of the deformation response of the coated and the uncoated foam in uniaxial quasi-static compression is summarized in the paper.

The micro-pattern gaseous pixel detector, is a promising technology for imaging and particle tracking applications. It is a combination of a gas layer acting as detection medium and a CMOS pixelated readout-chip. As a prevention against discharges we deposit a protection layer on the chip and then integrate on top a micromegas-like amplification structure. With this technology we are able to reconstruct 3D track segments of particles passing through the gas thanks to the functionality of the chip. We have turned a Timepix3 chip into a gaseous pixel detector and tested it at the SPS at Cern. The preliminary results are promising and within the expectations. However, the spark protection layer needs further improvement to make reliable detectors. For this reason, we have created a setup for spark-testing. We present the first results obtained from the lab-measurements along with preliminary results from the testbeam.

The radiation damage effects in silicon segmented detectors caused by X-rays have become recently an important research topic driven mainly by development of new detectors for applications at the European X-ray Free Electron Laser (E-XFEL). However, radiation damage in silicon strip is observed not only after extreme doses up to 1 GGy expected at E-XFEL, but also at doses in the range of tens of Gy, to which the detectors in laboratory instruments like X-ray diffractometers or X-ray spectrometers can be exposed. In this paper we report on investigation of radiation damage effects in a custom developed silicon strip detector used in laboratory diffractometers equipped with X-ray tubes. Our results show that significant degradation of detector performance occurs at low doses, well below 200 Gy, which can be reached during normal operation of laboratory instruments. Degradation of the detector energy resolution can be explained by increasing leakage current and increasing interstrip capacitance of the sensor. Another observed effect caused by accumulation of charge trapped in the surface oxide layer is change of charge division between adjacent strips. In addition, we have observed unexpected anomalies in the annealing process.

This paper describes an innovative beam diagnostic and monitoring system composed of a position sensitive detector and a residual range detector, based on scintillating optical fiber and on an innovative read-out strategy and reconstruction algorithm. The position sensitive detector consists of four layers of pre-aligned and juxtaposed scintillating fibres arranged to form two identical overlying and orthogonal planes. The 500 μm square section fibres are optically coupled to two Silicon Photomultiplier arrays using a channel reduction system patented by the Istituto Nazionale di Fisica Nucleare. The residual range detector is a stack of sixty parallel layers of the same fibres used in the position detector, each of which is optically coupled to a channel of Silicon Photomultiplier array by wavelength shifting fibres. The sensitive area of the two detectors is 9 × 9 cm². After being fully characterized at CATANA proton therapy facility, the performance of the prototypes was tested during last year also at TIFPA proton irradiation facility. The unique feature of these detectors is the possibility to work in imaging conditions (e.g. a particle at a time up to 10⁶ particles per second) and in therapy conditions up to 10⁹ particles per second. The combined use of the two detectors, in imaging conditions, as an example of application, allows the particle radiography of an object. In therapy conditions, in particular, the system measures the position, the profiles, the energy and the fluence of the beam.

JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector under development for photon science applications at free electron laser and synchrotron facilities. In particular, JUNGFRAU detectors will equip the Aramis end stations of SwissFEL, an X-ray free electron laser currently under construction at the Paul Scherrer Institut in Villigen, Switzerland. JUNGFRAU has been designed specifically to meet the challenges of photon science at XFELs, including high frame rates, single photon sensitivity in combination with a high dynamic range, vacuum compatibility and tilable modules. This has resulted in a charge integrating detector with three dynamically adjusting gains, a low noise of 55 ENC RMS, readout speeds in excess of 2 kHz, single photon sensitivity down to 2 keV (with a signal to noise ratio of 10) and a dynamic range covering four orders of magnitude at 12 keV. Each JUNGFRAU module consists of eight chips of 256 × 256 pixels, each 75 × 75 μm² in size. The chips are arranged in 2 × 4 formation and bump-bonded to a single silicon sensor 320 μm thick, resulting in an active area of approximately 4 × 8 cm² per module. Multi-module vacuum compatible systems comprising up to 16 Mpixels (32 modules) will be used at SwissFEL. The design of SwissFEL and the JUNGFRAU system for the Aramis end station A will be introduced, together with results from early prototypes and a characterisation using the first batch of final JUNGFRAU modules. Plans and first results of the pixel-by-pixel calibration will also be shown. The vacuum compatibility of the JUNGFRAU module is demonstrated for the first time.

We report on the recent demonstration of proton acceleration from a purpose-made Ti:Sapphire laser system. In the first successful series of autumn 2015, running at 2 TW peak power and 100 Hz diode pump rate, protons up to 0.7 MeV have been spectrally characterised. Subsequently, at increased laser pulse energy and improved contrast, we have obtained maximum particle energies around 1.7 MeV. These results, achieved in single-shot mode with a variety of thin foil targets, are an important step towards our aim of a stable, compact proton accelerator with high rate capacity.

The T-REX project of the group of the University of Zaragoza includes a number of R&D and prototyping activities to explore the applicability of gaseous Time Projection Chambers (TPCs) with Micromesh Gas Structures (Micromegas) in rare event searches where the pattern recognition of the signal is crucial for background discrimination. In the CAST experiment (CERN Axion Solar Telescope) a background level as low as 0.8 × 10⁻⁶ counts keV⁻¹ cm⁻² s⁻¹ was achieved. Prototyping and simulations promise a 10⁵ better signal-to-noise ratio than CAST for the future IAXO (International Axion Observatory) using x-ray telescopes. A new strategy is also explored in the search of WIMPS based on high gas pressure: the TREX-DM experiment, a low energy threshold detector. In both cases, axion and WIMP searches, the image of the expected signal is quite simple: a one cluster deposition coming from the magnet bore in the case of axions and, if possible, with a tadpole form in the case of WIMPs. It is the case of double beta decay (DBD) where imaging and pattern recognition play a major role. Results obtained in Xe + trimethylamine (TMA) mixture point to a reduction in electron diffusion which improves the quality of the topological pattern, with a positive impact on the discrimination capability, as shown in TREX-ββ prototype. Microbulk Micromegas are able to image the DBD ionization signature with high quality while, at the same time, measuring its energy deposition with a resolution of at least a ∼ 3% FWHM at the transition energy Q_ββ and even better (up to ∼ 1% FWHM) as extrapolated from low energy events. That makes Micromegas-based HPXe TPC a very competitive technique for the next generation DBD experiments (as PANDAX-III). Here, it will be shown the last results of the TREX project detectors and software concerning Axions, Dark matter and double beta decay.

To exploit the full discovery potential of the Large Hadron Collider an upgrade towards high luminosity (HL-LHC) is scheduled for 2024–25. Simultaneously to the accelerator, the experiments have to adapt to the expected higher particle rates and detector occupancy. Within the next long shutdown in 2019-20 the innermost end-cap regions of the ATLAS Muon spectrometer will be replaced by the New Small Wheels (NSW) including Micromegas detector modules of several m² size.

The Micromegas readout anode boards, representing the core components of the detector, are manufactured in industry, making the NSW Micromegas the first Micro Pattern Gaseous Detector (MPGD) for a major LHC experiment with a crucial industrial contribution. Production of the up to 2.2 m long boards is a serious challenge for industrialization technology and quality control methods.

The differential pressure of a conventional manometer is highly dependent on the atmospheric pressure. The measurements with a manometer for an extended time period show a large variation due to solar atmospheric tides. However, the measurements of absolute pressure, both outside and inside of a resistive plate chamber (RPC), are independent of each other. By monitoring the absolute pressures, both outside and inside of a RPC, along with the temperature, its leakage rate can be estimated. During the test period, the supporting button spacers inside a RPC may get detached due to some manufacturing defect. This effect can be detected clearly by observing the sudden fall of pressure inside the chamber.

We study the performance of a large-area 2-D Multigap Resistive Plate Chamber (MRPC) designed for muon tomography with high spatial resolution. An efficiency up to 98% and a spatial resolution of around 270 μ m are obtained in cosmic ray and X-ray tests. The performance of the MRPC is also investigated for two working gases: standard gas and pure Freon. The result shows that the MRPC working in pure Freon can provide higher efficiency and better spatial resolution.

Ground-based gamma-ray astronomy in the Very High Energy (VHE, E > 100 GeV) regime has fast become one of the most interesting and productive sub-fields of astrophysics today. Utilizing the Imaging Atmospheric Cherenkov Technique (IACT) to reconstruct the energy and direction of incoming gamma-ray photons from the universe, several source-classes have been revealed by previous and current generations of IACT telescopes (e.g. Whipple, MAGIC, HESS and VERITAS). The next generation pointing IACT experiment, the Cherenkov Telescope Array (CTA), will provide increased sensitivity across a wider energy range and with better angular resolution. With the development of CTA, the future of IACT pointing arrays is being directed towards having more and more telescopes (and hence cameras), and therefore the need to develop low-cost pixels with acceptable light-collection efficiency is clear. One of the primary paths to the above goal is to replace Photomultiplier Tubes (PMTs) with Silicon-PMs (SiPMs) as the pixels in IACT telescope cameras. However SiPMs are not yet mature enough to replace PMTs for several reasons: sensitivity to unwanted longer wavelengths while lacking sensitivity at short wavelengths, small physical area, high cost, optical cross-talk and dark rates. Here we propose a novel method to build relatively low-cost SiPM-based pixels utilising a disk of wavelength-shifting material, which overcomes some of these drawbacks by collecting light over a larger area than standard SiPMs and improving sensitivity to shorter wavelengths while reducing background. We aim to optimise the design of such pixels, integrating them into an actual 7-pixel cluster which will be inserted into a MAGIC camera and tested during real observations. Results of simulations, laboratory measurements and the current status of the cluster design and development will be presented.

This talk, as usual, has the purpose to focus on the main, most recent RPCs achievements and to extrapolate to new fields where they could be competitively applied. This approach suggests now the following considerations. The timing performance will be crucial for detectors at future accelerators. The idea of a 4D tracking combining space and time is a suggestive perspective of application for RPCs. Recent results indicate that another important field of application can be calorimetry at high time resolution. RPCs have already shown their potential in cosmic ray physics with ground based detectors. This potential has to be reinvested and further developed in new experiments. A last consideration is that RPC themselves can be a powerful instrument to investigate electrical phenomena in gaseous media.

The Extreme Energy Events (EEE) Project is devoted to the study of Extensive Atmospheric Showers through a network of muon telescopes, installed in High Schools, with the further aim of introducing young students to particle and astroparticle physics. Each telescope is a tracking detector composed of three Multi-gap Resistive Plate Chambers (MRPC) with an active area of 1.60 × 0.80 m². Their characteristics are similar to the ones built for the Time Of Flight array of the ALICE Experimentat LHC . The EEE Project started with a few pilot towns, where the telescopes have been taking data since 2008, and it has been constantly extended, reaching at present more than 50 MRPCs telescopes. They are spread across Italy with two additional stations at CERN, covering an area of around 3 × 10⁵ km², with a total surface area for all the MRPCs of 190 m². A comprehensive description of the MRPCs network is reported here: efficiency, time and spatial resolution measured using cosmic rays hitting the telescopes. The most recent results on the detector and physics performance from a series of coordinated data acquisition periods are also presented.

The upgrade of the LHC to the HL-LHC requires a new ITk detector. The innermost part of this new tracker is a pixel detector. The University of Wuppertal is developing a new DCS to monitor and control this new pixel detector. The current concept envisions three parallel paths of the DCS. The first path, called security path, is hardwired and provides an interlock system to guarantee the safety of the detector and human beings. The second path is a control path. This path is used to supervise the entire detector. The control path has its own communication lines independent from the regular data readout for reliable operation. The third path is for diagnostics and provides information on demand. It is merged with the regular data readout and provides the highest granularity and most detailed information. To reduce the material budget, a serial power scheme is the baseline for the pixel modules. A new ASIC used in the control path is in development at Wuppertal for this serial power chain. A prototype exists already and a proof of principle was demonstrated. Development and research is ongoing to guarantee the correct operation of the new ASIC in the harsh environment of the HL-LHC. The concept for the new DCS will be presented in this paper. A focus will be made on the development of the DCS chip, used for monitoring and control of pixel modules in a serial power chain.

The development of low resistivity material to increase the rate capability of Resistive Plate Chambers (RPCs) has been attracting more and more attention recently. This paper presents a new type of such a material. The new material is based on polyimide doped with carbon. The electrical volume resistivity of this material could be controlled using different percentages of the doping carbon. The standard thickness of polyimide carbon films is around 40 μm which does not allow to use it as such to build the RPC electrodes. To overcome this, we developed a new stress method to make the gap between two polyimide carbon films. In this paper we will introduce the new detector material, the new type of RPC and the cosmic bench test results. In the future, if the polyimide is widely used in RPCs, the electrical properties changed by high energy particles should be well-studied.

In this paper we report the initial results from our second generation of 3D silicon detectors for neutrons. The devices are briefly described and the first functional characterization tests carried out in laboratory before coupling to neutron converter material are reported. Particular emphasis is given to the read-out system used for the suppression of signals induced by γ-rays, that is one of the main issues in neutron detection. Experimental results are discussed with the aid of TCAD simulations.

There are many sources of position dependent variation of the intrinsic gain of a single gap RPC, e.g. variation of the thickness of the glass electrodes, the buttons and spacers, different composition of the gas mixture due to improper gas flow, leakage etc. One of the dominant components of the time resolution of a large area single gap RPC is this position dependent gain. Also, there is a variation of timing information as a function of the strip multiplicity as well as the lateral position of the trajectory in the RPC strip coordinate. This paper describes the technique of offline time correction to achieve a time resolution better than a ns. This technique is validated using a large cosmic ray dataset collected with a stack of twelve, 1×1 m² RPCs at TIFR. This paper also mentions a few alternate solutions to improve the time resolution during the operational phase of the INO-ICAL experiment. All these solutions are not only valid for INO, but also for any experiment with large RPC detectors.

Purpose: particle therapy has the potential to improve radiooncology. With more and more facilities coming into operation, also the interest for research at proton beams increases. Though many centers provide beam at an experimental room, some of them do not feature a device for radiation field shaping, a so called nozzle. Therefore, a robust and cost-effective double-scattering system for horizontal proton beamlines has been designed and implemented. Materials and methods: the nozzle is based on the double scattering technique. Two lead scatterers, an aluminum ridge-filter and two brass collimators were optimized in a simulation study to form a laterally homogeneous 10 cm × 10 cm field with a spread-out Bragg-peak (SOBP). The parts were mainly manufactured using 3D printing techniques and the system was set up at OncoRay's experimental beamline. Measurement of the radiation field were carried out using a water phantom. Results: high levels of dose homogeneity were found in lateral (dose variation ΔD/D < ±2%) as well as in beam direction (ΔD/D < ± 3% in the SOBP). The system has already been used for radiobiology and physical experiments. Conclusion: the presented setup allows for creating clinically realistic extended radiation fields at fixed horizontal proton beamlines and is ready to use for internal and external users. The excellent performance combined with the simplistic design let it appear as a valuable option for proton therapy centers intending to foster their experimental portfolio.