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On the study of inclusive semileptonic decays of Bs-meson from lattice QCD
Get PDFIn this contribution we describe a recent study, published in Gam- bino P. et al., JHEP, 07 (2022) 083, focused on the lattice calculation of inclusive decay rates of heavy mesons. We show how the inclusive calculation can be achieved starting from four-point lattice correlation functions normalised appropriately. The correlators used in this project come from gauge ensembles provided by the JLQCD and ETM collaborations. An essential point of this method is the extraction of spectral densities from lattice correlators which is obtained using two of the most recent approaches in the literature. Our results are in remarkable agreement with analytical predictions from the operator-product expansion. This study represents the first step towards a full lattice QCD study of heavy mesons inclusive semileptonic decays
Simulation and tools for the IDEA detector concept
Get PDFIDEA (Innovative Detector for an Electron-positron Accelerator) is an innovative general-purpose detector concept, designed to study electron-positron collisions at future e+e− circular colliders (i.e., FCC-ee). The IDEA detector con- sists of a silicon vertex detector, a very large and very light drift chamber surrounded by a layer of silicon detectors, a super-thin low-mass superconducting magnet, a pre- shower detector, a dual-readout calorimeter, and muon chambers inside the return joke of the magnet. The research and development conducted in the laboratory and the data taken from the various test beams to measure the performance of the prototypes of the various subdetectors must be accompanied by a verification that these performances are adequate to satisfy the extensive physics program of FCC-ee. The IDEA description was then implemented in a detailed simulation with Geant4 but also in a quick simulation with Delphes. This report describes the state of the simulations and the results of studies obtained in the context of physics analyses for FCC-ee. New algorithms for τ identification and electron energy regression in the calorimeter are also being developed with innovative machine learning methods which will be included in the global reconstruction of the particle flow event
Studies on the cooling systems of the Einstein Telescope cryogenic payloads
Get PDFEinstein Telescope (ET) is a third-generation gravitational wave detector that will cover a wide spectrum of frequencies measurable on the Earth’s surface, paying specific attention to low frequencies from a few Hz up to 10 Hz (ET-LF). At these frequencies, to achieve a sensitivity at least ten times better than that of current detectors, ET will have to develop innovative technologies that will make the reduction of noise sources possible, especially those of a thermal nature. Therefore, it will be necessary to cool the ET main optics and their suspensions (payload) at cryogenic temperature (10 - 20 K). This will require the development of new cooling techniques, low vibration noise of the cryogenic system and the study of high thermal conductivity and low mechanical dissipation materials. It is extremely important to not only ensure an efficient thermal connection between the payload and the cooling system, but also preserve the mechanical isolation and, therefore, avoid introducing excessive vibrations to the entire system. Here some preliminary studies carried on how to test cryogenic payloads using a test cryostat cooled by means of pulse tube refrigerators and how to cool the payload using superfluid helium-4 are presented
Anomaly Detection search for new resonances decaying into a Higgs boson and a generic new particle X in hadronic final states using s√=13 TeV pp collisions with the ATLAS detector
Get PDFA search is presented for heavy resonances decaying into a Higgs boson (H) and a new particle (X) in a fully hadronic final state with the ATLAS detector at the CERN Large Hadron Collider (LHC) (ATLAS Collaboration, JINST, 3 (2008) S08003). The full Run II of LHC is analyzed, corresponding to an integrated luminosity of 139 fb−1. A novel discovery signal region is imple- mented based on a jet-level anomaly score for signal model-independent tagging of the boosted X boson, representing the first application of fully unsupervised machine learning to an ATLAS analysis. No significant deviation from the SM is observed, so the results are interpreted in upper limits at 95% of confidence level (C.L.) on the production cross section σ(pp → Y → XH) (ATLAS Collaboration, Phys. Rev. D, 108 (2023) 052009)
Giving Voice to Silence. Material and Immaterial Evidence of the Female World and Childhood from the Coroplastic Perspective. Proceedings of the Webinar (September 21-22, 2022)
Get PDFIl volume raccoglie i contributi presentati nel webinar intitolato “Voice to the Silence. Materiality and Immateriality of the Female World and Childhood from the Coroplastic Perspective”, tenutosi il 21 e 22 settembre 2022 presso l’Istituto di scienze del patrimonio culturale del Cnr. L’incontro internazionale è stato organizzato nell’ambito del progetto PRIN2017 “Peoples of the Middle Sea. Innovation and Integration in Ancient Mediterranean (1600‐500 BC)”, con l’obiettivo di dar voce a donne e bambini attraverso la documentazione archeologica, in particolare la coroplastica, datata tra l’Età del Bronzo e il periodo ellenistico. Nonostante la loro evidente importanza nelle società antiche, questi due gruppi umani sono stati spesso trascurati dalla “storia ufficiale” e nelle ricostruzioni delle rispettive comunità. Nel corso del webinar e nei dieci contributi del volume, quindi, si è inteso mettere in discussione la marginalità di donne e bambini, esplorandone i molteplici ruoli in una prospettiva diacronica e mediterrane
Inclusive and differential σtt¯ measurements using the ATLAS detector
Get PDFMeasurements of the total and differential top-quark pair-production cross-sections in proton proton collisions at 13 TeV with the ATLAS detector at the Large Hadron Collider (LHC) are presented. The measurements use data collected
by ATLAS during the entire LHC Run 2 (2015 - 2018) corresponding to an integrated luminosity of 140 fb−1. The measurements are performed in the di-lepton channel, requiring an opposite-charge high-pT electron-muon pair and b-tagged jets. The experimental uncertainties due to the identification of b-quark jets are constrained in-situ by data. The total cross-section is compared to predictions by theoretical QCD calculations at next-to-next-to-leading (NNLO) order. Absolute and normalised single- and double-differential cross-sections are calculated as a function
of single-lepton and dilepton kinematic variables, featuring finer granularity and extended kinematic range compared to previous ATLAS measurements. The results are compared with multiple predictions from next-to-leading-order QCD matrixelement generators matched with parton-shower generators
YSF talk: Search for new physics in top quark production with additional leptons using the framework of effective field theory
Get PDFThis analysis presents a search for new physics impacting associated top quark production within the context of effective field theory (EFT). Making use of 138 fb−1 of proton-proton collisions at √s = 13 TeV collected by the CMS
experiment at the CERN LHC during 2016-2018, the analysis selects events with multiple jets, b-tagged jets, and two same-sign leptons or three or more leptons. The data are further binned according to kinematical distributions associated with the transverse momentum of the objects in the event. The effects of 26 dimensionsix EFT operators are incorporated into the simulation, allowing for the predicted
yields in each observable bin to be parameterized in terms of the strengths of the 26 EFT operators. A simultaneous fit of the 26 EFT parameters to the observed data is performed, and confidence intervals are extracted. The results are consistent with the standard model prediction
Electric dipole strength of 52Ca
Get PDFThe electric dipole strength above the one-neutron separation energy has been measured in the neutron-rich nucleus 52Ca using the Coulomb excitation at 223 MeV/nucleon in inverse kinematics. The γ-ray detector array CATANA, the neutron detector NeuLAND demonstrator, and the SAMURAI spectrometer at RIKEN Nishina Center were combined to reconstruct the excitation energy of 52Ca. A observed sharp peak at the very low neutron energy in the 52Ca → 51Ca +n channel indicates that 52Ca has a sizable amount of dipole strength just above the one neutron threshold
Collective wavefunction of Yrast states in 50Cr
Get PDFIn the generator coordinate method the wavefunctions are defined with respect to reference states that can indicate different shapes and deformations, which are examples of collective generator coordinates. In this work, we study the collective wavefunctions of Yrast states up to the terminating state of 50Cr using a recently introduced framework to calculate projected states of spins up to I = 14 based on effective Hamiltonians and a 5 dimensional collective coordinate space
Ground-breaking developments in 10B with inelastic proton scattering
Get PDFWe performed an experiment to measure weak γ-decay branching ratios and study angular distributions of γ-decay transitions in 10B for constraining ab initio calculations at the 9 MV Tandem accelerator of the Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH). In the experi- ment, large-volume LaBr3:Ce and CeBr3 scintillators having sufficient efficiency for high energy γ rays were used. In this paper, we present γ-ray intensities obtained from single γ-decay spectra emitted in the 10B(p,p′γ)10B∗ reaction at 8.5 MeV