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In recent years, the resistive cylindrical chamber (RCC) has been introduced as a novel gaseous detector, extending the well-established resistive plate chambers (RPCs) to the case of cylindrical electrode geometry. Preliminary experimental studies, although still limited in number and performed under experimental conditions not always fully controlled, have nevertheless highlighted several promising features of this detector configuration, motivating the need for further systematic investigations of its operation. In contrast, from the simulation perspective, detailed studies of the RCC have not been performed yet, despite the fact that the cylindrical geometry introduces new degrees of freedom – such as cylinder electrodes radii and voltage polarity – which lead to asymmetric behaviour of the avalanche development according to the polarity of the applied voltage between the electrodes. In this work we present a standalone simulation program specifically designed to model avalanche growth and signal induction in both RPC and RCC geometries. The code implements a stepwise transport model for electron multiplication, includes approximate space-charge effects, and evaluates the induced signals on an external electrode. The simulation has been validated against experimental data for planar RPCs and subsequently applied to RCC geometries with the primary goal of investigating the underlying physical features of the cylindrical detector configuration. The results show that key observables such as induced charge and efficiency are well reproduced in the planar case, and they highlight the role of the electric-field asymmetry in shaping avalanche dynamics in the cylindrical geometry. A first comparison with available RCC experimental data is also presented, providing an initial assessment of the model performance in realistic operating conditions.

Since 2019, a collaboration between researchers from various institutes and experiments (i.e., ATLAS, CMS, ALICE, LHCb/SHiP and the CERN EP-DT group) has been operating several RPCs with diverse electronics, gas gap thicknesses and detector layouts at the CERN Gamma Irradiation Facility (GIF++). The studies aim at assessing the performance of RPCs when filled with new eco-friendly gas mixtures in avalanche mode and in view of evaluating possible aging effects after long high background irradiation periods, for example, high-luminosity LHC phase. This challenging research is also part of a task of the European AidaInnova project. A promising eco-friendly gas identified for RPC operation is the tetrafluoruropropene (C 3 H 2 F 4 , commercially known as HFO-1234ze) that has been studied at the CERN GIF++ in combination with different percentages of CO 2 . Between the end of 2021 and 2022, several beam tests have been carried out to establish the performance of RPCs operated with such mixtures before starting the irradiation campaign for the aging study. Results of these tests for different RPCs layouts and different gas mixtures, under increasing background rates are presented here, together with the preliminary outcome of the detector aging tests.

CYGNO is a project realising a cubic meter demonstrator to study the scalability of the performance of the optical approach for the readout of large-volume, GEM-equipped TPC. This is part of the CYGNUS proto-collaboration which aims at constructing a network of underground observatories for directional Dark Matter search. The combined use of high-granularity sCMOS and fast sensors for reading out the light produced in GEM channels during the multiplication processes was shown to allow on one hand to reconstruct 3D direction of the tracks, offering accurate energy measurements and sensitivity to the source directionality and, on the other hand, a high particle identification capability very useful to distinguish nuclear recoils. Results of the performed R&D and future steps toward a 30-100 cubic meter experiment will be presented.

The performances of an optical readout of Time Projection Chambers (TPCs) with multiple Gas Electron Multipliers (GEMs) amplification stages are presented. The detector is characterized by using 55Fe photons converting inside a 7 litre sensitive volume detector in different electric field configurations. This prototype is developed as part of the R&D for the CYGNO project for an application to direct Dark Matter search by detection of tracks of nuclear recoils in the gas within the keV energy range.

The goal of the CYGNO project is to deploy at Laboratori Nazionali del Gran Sasso (LNGS) an high resolution Time Projection Chamber (TPC) with Gas Electron Multipliers (GEMs) amplification and optical 3D readout of an Helium/Fluorine based gas mixture for directional Dark Matter (DM) searches at low 1-10 GeV WIMP masses. The determination of the incoming direction of WIMP particles can in fact offer not only additional handles for discrimination of the annoying backgrounds, but especially an unique key for a positive, unambiguous identification of a DM signal.

Modern gas detectors for detection of particles require F-based gases for optimal performance. Recent regulations demand the use of environmentally unfriendly F-based gases to be limited or banned. This review studies properties of potential eco-friendly gas candidate replacements.

Systematic studies on the GEM foil material are performed to measure the moisture diffusion rate and saturation level. These studies are important because the presence of this compound inside the detector’ s foil can possibly change its mechanical and electrical properties, and in such a way, the detector performance can be affected. To understand this phenomenon, a model is developed with COMSOL Multiphysics v. 4.3 [1], which described the adsorption and diffusion within the geometry of GEM foil, the concentration profiles and the time required to saturate the foil. The COMSOL model is verified by experimental observations on a GEM foil sample. This note will describe the model and its experimental verification results.

In the last few years, an intense R &D activity on particle detectors for future HEP applications has been carried on with the aim of developing new techniques as well as studying the performance of already existing detectors when operated in a high rate environment. As for Resistive Plate Chamber detectors, the main challenges to face are the improvement of their detection capabilities and longevity at very high-rates, and the search for new eco-friendly gasmixtures free from greenhouse components. Results obtained in the framework of the RPC ECOGas@GIF++ Collaboration on a thin-Resistive Plate Chamber exposed at the CERN Gamma Irradiation Facility and operated with eco-friendly gas mixtures based on Tetrafluoropropene and Carbon dioxide will be discussed in this paper.

Results obtained by the RPC ECOgas@GIF++ Collaboration, using Resistive Plate Chambers operated with new, eco-friendly gas mixtures, based on tetrafluoropropene and carbon dioxide, are shown and discussed in this paper. Tests aimed to assess the performance of this kind of detectors in high-irradiation conditions, analogous to the ones foreseen for the coming years at the Large Hadron Collider experiments, were performed, and demonstrate a performance basically similar to the one obtained with the gas mixtures currently in use, based on tetrafluoroethane, which is being progressively phased out for its possible contribution to the greenhouse effect. Long term aging tests are also being carried out, with the goal to demonstrate the possibility of using these eco-friendly gas mixtures during the whole High Luminosity phase of the Large Hadron Collider.

The performances of an optical readout of Time Projection Chambers (TPCs) with multiple Gas Electron Multipliers (GEMs) amplification stages are presented. The detector is characterized by using 55 Fe photons converting inside a 7 litre sensitive volume detector in different electric field configurations. This prototype is developed as part of the R&D for the CYGNO project for an application to direct Dark Matter search by detection of tracks of nuclear recoils in the gas within the keV energy range.