Recognition of electron peaks and primary ionization clusters in real data-driven waveform signals is the main goal of research for the usage of the cluster counting technique in particle identification at future colliders. The state-of-the-art open-source algorithms fail in finding the cluster distribution Poisson behavior even in low-noise conditions. In this work, we present cutting-edge algorithms and their performance to search for electron peaks and identify ionization clusters in experimental data using the latest available computing tools and physics knowledge.

IDEA (Innovative Detector for an Electron-positron Accelerator) is a general-purpose detector concept, designed to study electron-positron collisions in a wide energy range from a very large circular leptonic collider. Its drift chamber is designed to provide an efficient tracking, a high precision momentum measurement and an excellent particle identification by exploiting the application of the cluster counting technique. To investigate the potential of the cluster counting techniques on physics events, a simulation of the ionization clusters generation is needed, therefore we developed an algorithm which can use the energy deposit information provided by Geant4 toolkit to reproduce, in a fast and convenient way, the clusters number distribution and the cluster size distribution. The results obtained confirm that the cluster counting technique allows to reach a resolution 2 times better than the traditional dE/dx method. A beam test has been performed during November 2021 at CERN on the H8 to validate the simulations results, to define the limiting effects for a fully efficient cluster counting and to count the number of electron clusters released by an ionizing track at a fixed $βγ$ as a function of the track angle. The simulation and the beam test results will be described briefly in this issue.

The CMD-3 experiment has been operating at the VEPP-2000 electron–positron collider, at the Budker Institute of Nuclear Physics, since December 2010. Its main goal is to measure the hadronic cross sections necessary to evaluate the anomalous magnetic moment of the muon. The discrepancy between the theoretical calculations and the experimental results obtained at the Brookhaven experiments is approximately 3.7 σ. The comparison between the results of the new "g-2" experiment at Fermilab and the theoretical calculation thanks to the new experimental contributions from CMD3 would provide important contributions to this measurement, which could prove the existence of New Physics. A key element for the success the CMD3 experiment is the tracking detector, which is a drift chamber built in the year 2009 at INFN of Lecce. Because of aging effects, its replacement is necessary. This paper presents the innovative design for the new ultralight CMD3 drift chamber.

Ultra-low mass and high granularity Drift Chambers fulfill the requirements of tracking systems for modern High Energy Physics experiments at future high luminosity accelerators (FCC or CEPC). The application of the Cluster Counting/Timing (CCT) technique adds a valuable particle identification capabilities with resolutions outperforming the traditional dE/dx technique. By measuring the arrival times of each individual ionization electron to the sense wire and by using suitable statistical tools it is possible to perform a bias free estimate of the impact parameter and a precise particle identification in drift chamber operating in a Helium based gas mixtures. The CCT technique consisting in identifying pulses due to different ionization electrons and in associating them in clusters according to their relative time delays, therefore it is necessary to have read-out interfaces capable of processing such high speed signals. This requires a data acquisition chain, able to manage the low amplitude signals from the sense wires (a similar to few mV) with a high bandwidth (similar to 1 GHz). Requirements on the drift chamber performance impose analog-to-digital conversions by a fast ADC at sample rates of at least 2 GS/s with 14-bit resolution. These constraints, together with maximum drift times and many readout channels, impose some sizeable data reduction strategy, while preserving all relevant information. Measuring both the amplitude and the arrival time of each peak in the signal associated to each ionization electron is the minimum requirement on the data transfer for storage to prevent any data loss. An electronic board including a Fast ADC and an FPGA for real-time processing of drift chamber signals is presented. The implementation of different algorithms for peaks finding are compared.

A bstract A search for the exclusive decays of the Higgs and Z bosons to a ϕ or ρ meson and a photon is performed with a pp collision data sample corresponding to an integrated luminosity of up to 35 . 6 fb −1 collected at $$ \sqrt{s}=13 $$ s = 13 TeV with the ATLAS detector at the CERN Large Hadron Collider. These decays have been suggested as a probe of the Higgs boson couplings to light quarks. No significant excess of events is observed above the background, as expected from the Standard Model. Upper limits at 95% confidence level were obtained on the branching fractions of the Higgs boson decays to ϕ γ and ρ γ of 4 . 8 × 10 −4 and 8 . 8 × 10 −4 , respectively. The corresponding 95% confidence level upper limits for the Z boson decays are 0 . 9 × 10 −6 and 25 × 10 −6 for ϕ γ and ρ γ, respectively.

A search for leptoquarks decaying into the bτ final state is performed using Run 2 proton-proton collision data from the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb−1 at √(s) = 13 TeV recorded by the ATLAS detector. The benchmark models considered in this search are vector leptoquarks with electric charge of 2/3e and scalar leptoquarks with an electric charge of 4/3e. No significant excess above the Standard Model prediction is observed, and 95

The CMD3 experiment has been operating at the VEPP-2000 electron-positron collider, at the Budker Institute of Nuclear Physics, since December 2010. Its main goal is to measure the hadronic cross sections necessary to evaluate the anomalous magnetic moment of the muon. The discrepancy between the theoretical calculations and the experimental results obtained at the Brookhaven experiments is approximately 3.7 sigma. The comparison between the results of the new "g-2'' experiment at Fermilab and the theoretical calculation with the new experimental contributions from CMD3 could confirm the discrepancy, which is a new important hint of New Physics. A key element for the success the CMD3 experiment is the tracking detector, which is a drift chamber built in the year 2009 at INFN of Lecce. Due to aging effects, its replacement is necessary, so that an innovative tracking detector, named TraPId (Tracking and Particle Identification), has been designed: an ultra-light drift chamber equipped with cluster counting/timing readout techniques, which exploits the expertise gained with the successful construction of the MEG II drift chamber. The drift chamber proposed for CMD3 will be also the prototype for the tracking system of the future Super Charm-Tau Factory detector (SCTF). In this paper, the new design of TraPId is described, with a focus on the mechanical design of the end plates, their novel tension recovery scheme and the expected performances.

The MEG-II experiment searches for the lepton-flavor-violating decay: μ⟶e+γ. The reconstruction of the positron trajectory uses a drift chamber operated with a mixture of He and iC4H10 gas. It is crucial to provide a stable performance of the detector in terms of its electron transport parameters, avalanche multiplication, composition and purity of the gas mixture. In order to have a continuous monitoring of the quality of the gas injected, we plan to install a small drift chamber, with a simple geometry that allows to measure very precisely the electron drift velocity in a prompt way. The chamber is a small box with cathode walls, that determine a highly uniform electric field inside two adjacent drift cells. Along the axis separating the two drift cells, four staggered sense wires alternated with five guard wires collect the drifting electrons. The trigger is provided by two 90Sr radioactive sources placed on top of a two thin scintillator tiles telescope. The whole system is designed to give a response in few minutes about drift velocity variations at the 10−3 level. In this paper the development of the drift chamber is presented, with a particular focus on the details of its construction.

F. Cuna,a,b,∗ G. Chiarello,c A. Corvaglia,b N. De Filippis,e, f E. Gorini,a,b F. Grancagnolo,b A. Miccoli,b M. Panareo,a,b M. Primavera,b G. F. Tassielli d,e and A. Ventura a,b aDipartimento di Matematica e Fisica "Ennio De Giorgi" Universitá del Salento, Via Arnesano, 73100 Lecce, Italy bIstituto Nazionale di Fisica Nucleare Sezione di Lecce, Via Arnesano, 73100 Lecce, Italy cIstituto Nazionale di Fisica Nucleare Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa, Italy dDipartimento Interateneo di Fisica "Michelangelo Merlin", Università degli Studi di Bari "Aldo Moro", Piazza Umberto I, 1, 70125 Bari, Italy eIstituto Nazionale di Fisica Nucleare Sezione di Bari, Via E. Orabona 4, 70125 Bari, Italy f Politecnico di Bari, Via Amendola 126/b, 70125 Bari, Italy

Large-size Resistive Micromegas have been chosen for the upgrade of the forward muon spectrometer of the ATLAS experiment, the New Small Wheel project. These chambers, together with small-strip Thin Gap Chambers (sTGC), allow reconstruction of high-momentum muon tracks in a high-radiation environment and provide a robust low-threshold single-muon trigger. A collaboration of seven INFN units built 32 SM1 type chambers, corresponding to one fourth of the total number needed for this upgrade. Each SM1 chamber has a surface of approximately 2 m2 and four sensitive layers. The production was shared among five INFN construction sites and it was completed in fall 2020. The construction methods, as well as the results of the quality tests done on components of the detector and on the assembled chambers, are reported in the present paper.

This Letter reports the observation of WWW production and a measurement of its cross section using 139 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from WWW production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive WWW production cross section is measured to be 820±100 (stat)±80 (syst) fb, approximately 2.6 standard deviations from the predicted cross section of 511±18 fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy.

The IDEA detector concept for a future $e^{+} e^{-}$ collider adopts an ultra-low mass drift chamber as the central tracking system. It is a He based, 4 m long and 4 m diameter, fully stereo drift chamber with a total material budget of $ \sim 0.016 X_{0} $ in the barrel part and $ \sim 0.05 X_{0} $ in the end-caps. It will be instrumented with a readout electronics implementing the Cluster Counting/Timing techniques, allowing for a larger than 3 $\sigma$ $\pi/\kappa$ separation over most of the momentum range of interest.

This letter presents a search for narrow, high-mass resonances in the Zγ final state with the Z boson decaying into a pair of electrons or muons. The s=13 TeV pp collision data were recorded by the ATLAS detector at the CERN Large Hadron Collider and have an integrated luminosity of 140 fb−1. The data are found to be in agreement with the Standard Model background expectation. Upper limits are set on the resonance production cross section times the decay branching ratio into Zγ. For spin-0 resonances produced via gluon–gluon fusion, the observed limits at 95% confidence level vary between 65.5 fb and 0.6 fb, while for spin-2 resonances produced via gluon–gluon fusion (or quark–antiquark initial states) limits vary between 77.4 (76.1) fb and 0.6 (0.5) fb, for the mass range from 220 GeV to 3400 GeV.

The first measurement of longitudinal decorrelations of harmonic flow amplitudes v_{n} for n=2-4 in Xe+Xe collisions at sqrt[s_{NN}]=5.44  TeV is obtained using 3  μb^{-1} of data with the ATLAS detector at the LHC. The decorrelation signal for v_{3} and v_{4} is found to be nearly independent of collision centrality and transverse momentum (p_{T}) requirements on final-state particles, but for v_{2} a strong centrality and p_{T} dependence is seen. When compared with the results from Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV, the longitudinal decorrelation signal in midcentral Xe+Xe collisions is found to be larger for v_{2}, but smaller for v_{3}. Current hydrodynamic models reproduce the ratios of the v_{n} measured in Xe+Xe collisions to those in Pb+Pb collisions but fail to describe the magnitudes and trends of the ratios of longitudinal flow decorrelations between Xe+Xe and Pb+Pb. The results on the system-size dependence provide new insights and an important lever arm to separate effects of the longitudinal structure of the initial state from other early and late time effects in heavy-ion collisions.

Supersymmetry is one of the most popular extensions of the Standard Model, but no evidence supporting its validity has been observed at LHC up to date. The second period of data taking at the LHC at 13 TeV of center of mass energy ($\sqrt{s}$), Run-2, started in 2015 and provides an important test field for the search of beyond the Standard Model physics. In particular, the production of supersymmetric electroweak particles, such as sleptons, neutralinos and charginos, could be a promising probe for SUSY signals at LHC, despite the lower cross sections if compared to the ones of the strong production processes. This proceeding summarizes some of the most recent ATLAS results obtained from the searches for sleptons, both produced directly or via $\tilde{\chi}_1^\pm$ or $\tilde{\chi}_2^0$ decays, with 36.1 fb$^{-1}$ of data collected in 2015-2016.

The production cross-sections for W +/- and Z bosons are measured using ATLAS data corresponding to an integrated luminosity of 4.0 pb-1 collected at a centre-ofmass energy v s = 2.76 TeV. The deca ...

In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100TeV. Its unprecedented centre of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries.

This change does not have any impact on the measured helicity fractions, but it changes the obtained limits on the anomalous couplings.

This paper reports searches for heavy resonances decaying into ZZ or ZW using data from proton-proton collisions at a centre-of-mass energy of √(s)=13 TeV. The data, corresponding to an integrated luminosity of 36.1 fb −1 , were recorded with the ATLAS detector in 2015 and 2016 at the Large Hadron Collider. The searches are performed in final states in which one Z boson decays into either a pair of light charged leptons (electrons and muons) or a pair of neutrinos, and the associated W boson or the other Z boson decays hadronically. No evidence of the production of heavy resonances is observed. Upper bounds on the production cross sections of heavy resonances times their decay branching ratios to ZZ or ZW are derived in the mass range 300-5000GeV within the context of Standard Model extensions with additional Higgs bosons, a heavy vector triplet or warped extra dimensions. Production through gluon-gluon fusion, Drell-Yan or vector-boson fusion are considered, depending on the assumed model.