Improving rate capability of Resistive Plate Chambers

The High Luminosity phase of Large Hadron Collider, foreseen to start in less then ten years from now, has triggered the development of a new generation of gaseous detectors with much improved performance with respect to the present ones. For what concerns Resistive Plate Chambers (RPCs), research is focusing on the methods to increase their rate capability, i.e. the maximum flux of impinging particles that these devices can stand without losing efficiency for a prolonged period of time. Different solutions are being proposed and extensively investigated upon. Here a brief overview of the physics processes taking place in RPCs at high rate is presented. The fundamental parameters that influence rate capability are taken into exam and the way how they can be optimized in order to increase rate capability is outlined. A comparison between the models used and experimental data confirms the goodness of the approach and the validity of results obtained

Resistive Plate Chambers with Gd-coated electrodes as thermal neutron detectors

Abstract Resistive Plate Chambers (RPCs) are wide spread, cheap, easy-to-build and large size detectors, used mainly to reveal ionising particles in high-energy physics experiments. Here a technique, consisting in coating the inner surface of the bakelite electrodes with a mixture of linseed oil and Gd 2 O 3 is reported. This allows to make RPCs sensitive also to thermal neutrons, making them suitable to be employed for industrial, medical or de-mining applications. Thermal neutron-sensitive RPCs can be operated at atmospheric pressure, are lightweighted, have low γ -ray sensitivity and are easy to handle even when large areas have to be covered. This paper reports the results of the first test of this detector, performed at the Geel Linear Accelerator (GELINA) in Belgium

Advancing Particle Identification in Helium-Based Drift Chambers: A Cluster Counting Technique Study through Beam Tests

While the ionization process by charged particles (dE/dx) is commonly used for particle identification, uncertainties in total energy deposition limit particle separation capabilities. To overcome this limitation, the cluster counting technique (dN/dx) leverages the Poisson nature of primary ionization, providing a statistically robust method for inferring mass information. Simulation studies using Garfield++ and Geant4 indicate that the cluster counting technique can achieve twice the resolution of the traditional dE/dx method in helium-based drift chambers. However, in real experimental data, finding electron peaks and identifying ionization clusters is extremely challenging due to the superimposition of signals in the time domain. To address these challenges, this paper introduces cutting-edge algorithms and modern computing tools for electron peak identification and ionization cluster recognition in experimental data. The effectiveness of the algorithms is validated through four beam tests conducted at CERN, involving different helium gas mixtures, varying gas gains, and various wire orientations relative to ionizing tracks. The tests employ a muon beam ranging from 1 GeV/c to 180 GeV/c, with drift tubes of different sizes and diameter sense wires. The data analysis results concerning the ascertainment of the Poisson nature of the cluster counting technique, the establishment of the most efficient cluster counting and electrons clustering algorithms among the various ones proposed, and the dependence of the counting efficiency versus the beam particle impact parameter will be discussed. Additionally, a study comparing the resolution obtained using the dN/dx and dE/dx methods will be presented

Recent results and developments on double-gap RPCs for CMS

Abstract A 3 mm wide-gap Resistive Plate Chamber, as proposed for CMS, has been tested in the H2 Cern beam line. Results on efficiency, rate capability, time resolution and cluster size are reported

Resistive Plate Chambers in avalanche mode: a comparison between model predictions and experimental results

Abstract In this paper a model simulating the main aspects of avalanche growth and signal development in Resistive Plate Chambers (RPCs) is presented. The model has been used to compute the performances, in particular, charge distribution and efficiency of single- double- and multi-gap RPCs, and to compare them with the available experimental results. This model could be used to optimize the characteristics of this type of detector with a view to its use in the future large experiments at LHC: ATLAS and CMS

Experimental results on RPC neutron sensitivity

Abstract RPC neutron sensitivity has been studied during two tests done with different neutrons energies. In the first test, neutrons from spontaneous fission events of 252 Cf were used (average energy 2 MeV ); while in the second test neutrons were produced using a 50 MeV deuteron beam on a 1 cm thick beryllium target (average energy 20 MeV ). Preliminary results show that the neutron sensitivity in double gap mode is (0.52±0.03)×10−3 at about 2 MeV and (5.3±0.5)×10−3 at about 20 MeV