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We discuss the thermal noise originating from distributed resistive materials in particle detectors like Resistive Plate Chambers or Resistive Micro-Pattern Gas Detectors. The complex impedance Z (f) of the detector as seen by the amplifier input terminal is the key number defining the noise power spectrum. We give some analytic examples and show how this number can be calculated for any detector geometry using numerical simulations programs. [ABSTRACT FROM AUTHOR]

We describe the development of a position-sensitive Gas Electron Multiplier detector prototype, providing for each ionizing event three coordinates: the cartesian X and Y, and U at 45 °. Simultaneous recording of the three projections permits ambiguity-free reconstruction of multiple tracks, and aims at operation in very high intensity radiation fields. [ABSTRACT FROM AUTHOR]

For detectors with resistive elements, the time dependence of the signals is not solely given by the movement of the charges in the drift medium but also by the time-dependent reaction of the resistive materials. In this report, we present a numerical way to capture this contribution by using the extended form of the Ramo–Shockley theorem for conductive media. As an example, the methodology will be applied to the MicroCAT two-dimensional interpolation readout to calculate the center of gravity position reconstruction distortion map of its readout cells. [ABSTRACT FROM AUTHOR]

The PICOSEC-Micromegas (PICOSEC-MM) detector is a novel gaseous detector designed for precise timing resolution in experimental measurements. It eliminates time jitter from charged particles in ionization gaps by using extreme UV Cherenkov light emitted in a crystal, detected by a Micromegas photodetector with an appropriate photocathode. The first single-channel prototype tested in 150 GeV/c muon beams achieved a timing resolution below 25 ps, a significant improvement compared to standard Micropattern Gaseous Detectors (MPGDs). This work explores the specifications for applying these detectors in monitored neutrino beams for the ENUBET Project. Key aspects include exploring resistive technologies, resilient photocathodes, and scalable electronics. New 7-pad resistive detectors are designed to handle the particle flux. In this paper, two potential scenarios are briefly considered: tagging electromagnetic showers with a timing resolution below 30 ps in an electromagnetic calorimeter as well as individual particles (mainly muons) with about 20 ps respectively. [ABSTRACT FROM AUTHOR]

This work explores the use of multichannel readout electronics, already in use for quality assurance in gain uniformity studies, to measure the uniformity of the induction gap in Gas Electron Multipliers (GEM) based detectors. The devised procedure also provides a qualification of the readout electrodes in terms of disconnected or shorted channels. The measurement is based on inducing a signal on the readout strips by pulsing the bottom layer of the GEM foil, and measuring the amplitude of the induced signal. In this work, signals are readout using the analog APV25 front-end chip and the Scalable Readout System (SRS) developed by the RD51 collaboration at CERN. Studies on small and large area GEM detectors, effects of mechanical stress, and of electric fields are presented. Sensitivity to defects in the readout plane is also verified. [ABSTRACT FROM AUTHOR]

The PICOSEC Micromegas detector is a precise timing gaseous detector based on a Cherenkov radiator coupled to a semi-transparent photocathode and a Micromegas amplifying structure. First single-pad prototypes demonstrated a time resolution below σ = 25 ps, however, to make the concept appropriate to physics applications, several developments are required. The objective of this work was to achieve an equivalent time resolution for a 10 × 10 cm 2 area PICOSEC Micromegas detector. The prototype was designed, produced and tested in the laboratory and successfully operated with a 80 GeV/c muon beam. Preliminary results for this device equipped with a CsI photocathode demonstrated a time resolution below σ = 25 ps for all measured pads. The time resolution was reduced to be below σ = 18 ps by decreasing the drift gap to 180 μ m and using dedicated RF amplifier cards as new electronics. The excellent timing performance of the single-channel proof of concept was not only transferred to the 100-channel prototype, but even improved, making the PICOSEC Micromegas detector more suitable for large-area experiments in need of detectors with high time resolutions. • 10 × 10 cm 2 PICOSEC MM detector successfully operated with a 80 GeV/c muon beam • Timing performance of a single-channel detector transferred to a 100-channel device • Time resolution of σ = 18 ps achieved for the 10 × 10 cm 2 PICOSEC MM detector [ABSTRACT FROM AUTHOR]

The VMM3a is an Application Specific Integrated Circuit (ASIC), specifically developed for the readout of gaseous detectors. Originally developed within the ATLAS New Small Wheel (NSW) upgrade, it has been successfully integrated into the Scalable Readout System (SRS) of the RD51 collaboration. This allows, to use the VMM3a also in small laboratory set-ups and mid-scale experiments, which make use of Micro-Pattern Gaseous Detectors (MPGDs). As part of the integration of the VMM3a into the SRS, the readout and data transfer scheme was optimised to reach a high rate-capability of the entire readout system and profit from the VMM3a's high single-channel rate-capability of 3.6 Mhits/s. The optimisation focused mainly on the handling of the data output stream of the VMM3a, but also on the development of a trigger-logic between the front-end cards and the DAQ computer. In this article, two firmware implementations of the non-ATLAS continuous readout mode are presented, as well as the implementation of the trigger-logic. Afterwards, a short overview on X-ray imaging results is presented, to illustrate the high rate-capability from an application point-of-view. [ABSTRACT FROM AUTHOR]

The integration of the VMM3a Application-Specific Integrated Circuit (ASIC) into RD51's Scalable Readout System (SRS) provides a versatile tool for the readout of Micro-Pattern Gaseous Detectors (MPGDs). With its self-triggered high-rate readout, its analogue part that allows to get information on the deposited energy in the detector, and its so-called neighbouring-logic that allows to recover information on the charge distribution, this new system has features of particular interest for digital X-ray imaging. In the present article, we want to emphasise the capabilities of VMM3a/SRS by presenting results of X-ray imaging studies. We will highlight the advantages on the energy and the spatial resolution provided by the neighbouring-logic. In the first part, we focus on spatial resolution studies. We show how segmented readout structures introduce a repeating pattern in the distribution of the reconstructed positions (using the centre-of-gravity method) and how this behaviour can be mitigated with the neighbouring-logic. As part of these studies, we explore as well an alternative position reconstruction algorithm. In the second part of the article, we present the energy resolution studies. [ABSTRACT FROM AUTHOR]