arXiv subjects

Antonello Pellecchia

Publications and source records attributed to Antonello Pellecchia.

10 recordsLinked to original sources

arXiv2024

Design and optimization of a hadronic calorimeter based on micropattern gaseous detectors for a future experiment at the Muon Collider

Micro-pattern gaseous detectors (MPGDs) are a promising readout technology for hadronic calorimeters (HCAL) thanks to their good space resolution, longevity and rate capability. We describe the development of a HCAL based on MPGDs for an experiment at the proposed Muon Collider. The design of a semi-digital MPGD-HCAL is shown and its performance is calculated with Monte Carlo simulations with high-energy pions, showing an energy resolution down to 8\% for \SI{80}{\giga\eV} pions. We also present the performance of twelve MPGD prototypes with different technologies (MicroMegas, $μ$-RWELL and RPWELL) assembled and operated in test beam first with high-energy muons and later with pions in a hadronic calorimeter prototype of $\sim1\,λ_\text{I}$ length; the detectors have a good response uniformity (lower than 17\%) and space resolution and their performance in the calorimeter shows very good agreement with the Monte Carlo shower calculation.

physics.ins-det↗

arXiv2023

The upgrade of the CMS muon system for the High Luminosity LHC

The muon system of the CMS experiment is expected to upgrade all of its subdetectors for the Phase-2 of the Large Hadron Collider (LHC) that will begin in 2029. The upgrade plans for drift tubes (DTs), cathode strip chambers (CSCs) and resistive place chambers (RPCs) include a new electronics for better performance in high background rate conditions and to sustain the large radiation dose delivered by the high-luminosity LHC (HL-LHC). Two new RPC stations will also be installed to complement CSCs in the forward region $1.8 < |η| < 2.4$, while three stations of triple-GEM (gas electron multiplier) detectors will complement CSCs in the region $1.5 < |η| < 2.4$ and extend the CMS muon system coverage in the very forward pseudorapidity region up to $|η| = 2.8$. We present the goals and status of the CMS muon system upgrade including the performance of the early Phase-2 upgrades demonstrated in Run 3 with proton-proton collisions, the performance validation of the new detectors in test beams and the mass production status of the new stations.

physics.ins-det↗

arXiv2023

Triple-GEM detectors for the Phase-2 upgrade of the CMS muon spectrometer

The High-Luminosity LHC will deliver an unprecedented instantaneous luminosity, requiring all experiments to upgrade their detectors to sustain the higher background rates. The upgrade of the CMS Muon spectrometer includes three stations of triple-GEM detectors. We present the status of the commissioning and performance validation of the three GEM stations: GE1/1, which is taking data in Run 3, GE2/1, for which the first detectors will be installed in 2024, and ME0, which has undergone several performance studies for high-rate and longevity and will start its mass production in 2024.

physics.ins-det↗

arXiv2023

Production and characterization of random electrode sectorization in GEM foils

In triple-GEM detectors, the segmentation of GEM foils in electrically independent sectors allows reducing the probability of discharge damage to the detector and improving the detector rate capability; however, a segmented foil presents thin dead regions in the separation between two sectors and the segmentation pattern has to be manually aligned with the GEM hole pattern during the foil manufacturing, a procedure potentially sensitive to errors. We describe the production and characterization of triple-GEM detectors produced with an innovative GEM foil segmentation technique, the ``random hole segmentation'', that allows an easier manufacturing of segmented GEM foils. The electrical stability to high voltage and the gain uniformity of a random-hole segmented triple-GEM prototype are measured. The results of a test beam on a prototype assembled for the Phase-2 GEM upgrade of the CMS experiment are also presented; a high-statistics efficiency measurement shows that the random hole segmentation can limit the efficiency loss of the detector in the areas between two sectors, making it a viable alternative to blank segmentation for the GEM foil manufacturing of large-area detector systems.

physics.ins-det↗

arXiv2022

Performance of triple-GEM detectors for the CMS Phase-2 upgrade measured in test beam

Triple-GEM detectors for the GE2/1 and ME0 stations of the endcap muon system for the Phase-2 upgrade of the CMS Experiment have been operated in a test beam to measure their efficiency and spatial resolution, together with a high spatial resolution triple- GEM tracker. A production module of GE2/1 detectors and a prototype ME0 detector show excellent local efficiency. A prototype detector with GEM foils employing random hole sectorization showed significant reduction of dead areas. The spatial resolution of the tracker has been measured and found close to the expected value of 75 μm.

physics.ins-det↗

arXiv2022

Simulated Detector Performance at the Muon Collider

In this paper we report on the current status of studies on the expected performance for a detector designed to operate in a muon collider environment. Beam-induced backgrounds (BIB) represent the main challenge in the design of the detector and the event reconstruction algorithms. The current detector design aims to show that satisfactory performance can be achieved, while further optimizations are expected to significantly improve the overall performance. We present the characterization of the expected beam-induced background, describe the detector design and software used for detailed event simulations taking into account BIB effects. The expected performance of charged-particle reconstruction, jets, electrons, photons and muons is discussed, including an initial study on heavy-flavor jet tagging. A simple method to measure the delivered luminosity is also described. Overall, the proposed design and reconstruction algorithms can successfully reconstruct the high transverse-momentum objects needed to carry out a broad physics program.

hep-ex↗

arXiv2022

Promising Technologies and R&D Directions for the Future Muon Collider Detectors

Among the post-LHC generation of particle accelerators, the muon collider represents a unique machine with capability to provide very high energy leptonic collisions and to open the path to a vast and mostly unexplored physics programme. However, on the experimental side, such great physics potential is accompanied by unprecedented technological challenges, due to the fact that muons are unstable particles. Their decay products interact with the machine elements and produce an intense flux of background particles that eventually reach the detector and may degrade its performance. In this paper, we present technologies that have a potential to match the challenging specifications of a muon collider detector and outline a path forward for the future R&D efforts.

physics.ins-det↗

arXiv2022

Rate capability of large-area triple-GEM detectors and new foil design for the innermost station, ME0, of the CMS endcap muon system

To extend the acceptance of the CMS muon spectrometer to the region 2.4 $<|η|<$ 2.8, stacks of triple-GEM chambers, forming the ME0 station, are planned for the CMS Phase 2 Upgrade. These large-area micro-pattern gaseous detectors must operate in a challenging environment with expected background particle fluxes up to 150 kHz/cm$^2$. Unlike traditional non-resistive gaseous detectors, the rate capability of such triple-GEM detectors is limited not by space charge effects, but by voltage drops on the chamber electrodes due to avalanche-induced currents flowing through the resistive protection circuits (introduced as discharge quenchers). We present a study of the irradiation of large-area triple-GEM detectors with moderate fluxes to obtain a high integrated hit rate. The results show drops as high as 40% of the nominal detector gas gain, which would result in severe loss of tracking efficiency. We discuss possible mitigation strategies leading to a new design for the GEM foils with electrode segmentation in the radial direction, instead of the "traditional" transverse segmentation. The advantages of the new design include uniform hit rate across different sectors, minimization of gain-loss without the need for voltage compensation, and independence of detector gain on background flux shape.

physics.ins-det↗

arXiv2021

Performance of a fast timing micro-pattern gaseous detector for future collider experiments

The fast timing MPGD is a micro-pattern gaseous detector conceived for achieving sub-nanosecond time resolution while maintaining the ability to instrument large areas in high-rate environments; applications of such technology are perspected in high-energy physics experiments at future colliders and medical diagnostics with time-of-flight methods. This work shows the systematic studies carried on an FTM prototype on the performance of GEM foils coated with resistive DLC films, whose development is essential for the FTM operation. The resistive foil performance has been tested with several gas mixtures and compared with the results obtained on conductive foils. The results show that the performance of the FTM is presently limited by the technology of manufacturing of DLC-coated GEM foils, with high gains reachable exclusively in isobuthane-based mixtures.

physics.ins-det↗

arXiv2020

A UV laser test bench for micro-pattern gaseous detectors

UV lasers for the calibration of gaseous detectors have seen newfound employment with current-generation micro-pattern gaseous detectors (MPGDs), especially those devices not suitable for tests with traditional sources (e.g. cosmic rays or X-ray beams) by design constraints. An apparatus made of a UV laser designed for the characterization of the fast timing MPGD (FTM) is here described, together with the measurements of gain curve and electron drift velocity performed on a prototype of Time Projection GEM (TPG) to validate the setup.

physics.ins-det↗