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Trigger and identification strategies for the search of Higgs boson pair production in the bbττ final state in the ATLAS experiment
Full text linkMeasuring the Higgs boson self-coupling is one of the primary objectives of the High Luminosity Large Hadron Collider (HL-LHC). Optimizing and upgrading the sensitivity to its signals is therefore crucial. During Run 2, the LHC
achieved an integrated luminosity of 140 fb−1 for proton-proton collisions at 13 TeV, and this figure is expected to at least double by the end of the ongoing Run 3. De
spite this increase, the low di-Higgs production cross-section requires significantly higher data statistics to observe this process. Hence, improving signal acceptance
and efficiency, starting with enhanced trigger selections, is essential to reducing the necessary data volume for this measurement. This paper presents the latest results of an ongoing study focused on optimizing the trade-off between acceptance in the bbττ channel and the total trigger rate within the ATLAS experiment’s High-Level trigger. A notable advancement in this research is the introduction of a new b+τ trigger, which offers a superior efficiency-rate trade off compared to previous upgrades. Additionally, enhancements in identification algorithms through the inclusion of new variables have significantly improved background rejection power. These improvements are part of the comprehensive ATLAS effort to increase sensitivity to Higgs boson self-coupling measurements
Breviario giuridico della cybersicurezza
Full text linkIl Breviario è uno strumento agile per documentarsi e approfondire gli aspetti giuridico-istituzionali delle cybersicurezza e per districarsi più agevolmente in un complesso panorama normativo in continua evoluzione.
L’opera contiene un’analisi sistematica dei principali concetti giuridico-informatici che ricorrono nella regolazione in materia di cybersicurezza, proponendosi come una vera e propria guida semplificata sulle norme di settore.
«La pregevolezza di questo lavoro sta nell’avvicinare il lettore, con semplicità e linearità espositiva, qualità che tuttavia non tradiscono la tecnicità degli argomenti trattati, a una materia che sembra riservata agli ultraspecialisti e che nasconde insidie e ambiguità spesso fuorvianti». (Bruno Frattasi, Direttore Generale dell’Agenzia per la cybersicurezza nazionale)
Etica della ricerca sul Patrimonio culturale. Problemi e prospettive
Full text linkIl volume raccoglie una serie di saggi brevi, a firma di autorevoli studiosi ed esperti della materia, sul tema dell’Etica della ricerca sul Patrimonio culturale, declinata nei differenti campi nei quali si articolano le discipline storiche e archeologiche. L’obiettivo è quello di mettere in evidenza e discutere criticamente le problematiche di ordine etico che si riscontrano nello svolgimento dell’attività di ricerca, conservazione, valorizzazione e comunicazione del Patrimonio culturale, storico e archeologico
Probing the dynamical evolution of QGP using charge-dependent correlations and fluctuations at CMS
Full text linkWe present the first studies of net-charge fluctuations and charge-balance functions using the broad rapidity coverage of the CMS experiment. These types of event-by-event fluctuations are a powerful tool to characterize the thermo
-dynamic properties of the quark-gluon plasma (QGP). The net-charge of the system is a conserved quantity, meaning its fluctuations are sensitive to the QGP formation and phase transition. It therefore provides an understanding of strong interactions complementary to that from the charge -balance function. Relative to past measurements which probed a limited phase space region, we extract fluctuations up to
a pseudo-rapidity separation of Δη = 4.8, and as such, significantly improving the sensitivity to test what has been theoretically predicted for the QGP formation. In turn, the width of the balance function, both in relative |η| and relative azimuthal angle, is found to decrease with multiplicity for low particle transverse momentum (pT < 2 GeV/c). The effect is observed for both PbPb and pPb collisions, and it is consistent with a late hadronization scenario, where particles are produced at a later stage during the system evolution. The multiplicity dependence is weaker for higher pT, which signifies that the balancing charge partners are strongly correlated compared to the low-pT region. Model comparisons cannot reproduce the
multiplicity dependence of the width in Δη. However, a model which incorporates collective effects can reproduce the narrowing of the width
Deliverable 2.3 - Final report on methodology of land cover datasets for global and regional climate models, including publication of the data
Full text linkWithin OptFor-EU, forest-climate interactions are studied with different model approaches, which have different requirements on their land cover datasets. This document addresses the need for a land cover dataset with implemented forest management practices (FMPs) for regional climate models (RCMs). After the context for this deliverable in Section 1, the available datasets within this project are described in Section 2.
• LANDMATE PFT dataset: A high-resolution (~ 2 km) land cover dataset suitable for RCM studies on convection-permitting scales in Europe.
• LUCAS LUC dataset: A high-resolution (~ 10 km) dataset showing historical and projected land use and cover changes, including future scenarios such as SSP126, which represents strong afforestation in Europe.
• EFT dataset: A detailed and consistent dataset (D1.1) representing the tree distribution across Europe at 100 m horizontal resolution.
In Section 3, we describe the implementation of the FMP thinning into the LANDMATE PFT dataset for two selected Case Study Areas (CSAs,) CSA4 (Eastern Lowlands of Lower Saxony, Germany) and CSA6 (Arges and Teleorman county, Romania). We align our assumptions with the forest model experiments in D2.2 Report on new Forest Management Practices (FMP) in forest models and implications for land cover change parametrisation in climate models (Neumann et al. 2024b), and adapt them to the feasibility of regional climate model (RCM) studies. In the end, a land cover dataset with implemented FMP is created that shows a reduced tree fraction and an increased grass fraction in model grid cells. The dataset is published at 0.0275° horizontal resolution for the two selected CSAs on a rotated grid at an openly accessible Zenodo repository. For addressing a different grid or additional CSAs, the source code for creating the dataset is published as well (Pop et al. 2024). Section 4 gives an outlook on the implementation of this dataset into RCMs, which will affect land surface properties and lead to effects and feedback in the atmosphere through altered land-atmosphere exchange processes. Section 5 provides an overview of the data and code availability used for this deliverable
Measurement of η production rate in proton-proton collisions at 13 TeV with LHCf
Full text linkIndirect measurements of Ultra High Energy Cosmic Rays (UHECR) strongly depend on the hadronic interaction models used to simulate the interaction of a high energy cosmic ray with the atmosphere and thus the Extensive Air Shower (EAS). Different models bring to significantly different interpretations of the ground cosmic-ray measurements. The LHCf (Large Hadron Collider forward) experiment is a calorimetric experiment at LHC for the measurement of production rate of neutral particles in the forward region. The target of the experiment is to provide data in the
forward region at high energy for testing and tuning the different hadronic models. In LHC Run 2, LHCf acquired data in proton-proton collisions at 13 TeV. With these data we have measured for the first time the production rate of η mesons in the forward region at high energy. In this paper we will present the η production rate measurement, and we will compare it with different hadronic models typically
used by UHECR experiments
CMS track reconstruction performance and tracking developments during Run 3
Full text linkThe precise and efficient reconstruction of charged particle tracks is crucial for the success of the CMS experiment at the LHC. Prior to the start of LHC Run 3 in 2022, the first layer of the Tracker Barrel Pixel subdetector was replaced to cope with the high pileup environment, and significant upgrades were made to the track reconstruction algorithms. Measurements of track reconstruction performance based on data collected in 2022 and 2023 compared to simulation results are presented in this paper. This is then followed by a discussion of the ongoing developments to improve track reconstruction introduced for the remainder of Run 3 starting from 2024 and for the future
First evidence of B→Kνν¯ and recent results on radiative decays at Belle and Belle II
Full text linkThis proceeding summarized recent measurement of the Radiative decay of the B meson, with also a more detailed section on the first evidence of the B+ →K+νν at Belle II
Latest results on rare and very rare decays at LHCb
Full text linkThis contribution presents the most recent results related to rare and very rare decays at the LHCb experiment. These results encompass the J/ψ → μ+μ−μ+μ− and B0 s → μ+μ−γ decays, using data obtained from proton-proton collisions at a centre-of-mass energy of 13 TeV during the LHC Run 2
data-taking, corresponding to a total integrated luminosity of 5.4 fb−1. Additionally, this contribution includes the measurement of the branching fraction ratio B(φ →μ+μ−)/B(φ →e+e−) with charm meson decays and a comprehensive analysis of local and non-local amplitudes in the B0 → K∗0μ+μ− decay
Search for rare decays of the Higgs and Z bosons to ϕγ and ργ at the CMS experiment
Full text linkHiggs and Z boson decays into a photon and a ρ(770) and φ(1020) meson are searched for using proton-proton collision data collected by the CMS experiment at the LHC at CERN, at √s = 13 TeV. Events are selected in which the mesons decay into pairs of charged pions and pairs of charged kaons respectively. The analysed data sets correspond to an integrated luminosity of 40 fb−1. No significant excess above the background expectations is observed in any search channel. Upper limits at the 95% confidence level on the Higgs boson branching fractions into ρ(770) and φ(1020) are determined to be 3.74 × 10−4 and 2.97×10−4 respectively.
These results constitute the most stringent experimental limits to date on the afore-mentioned decay channels. Expected upper limits on the Z boson branching ratios are 6.56 × 10−6 and 2.21×10−6 for the ρ(770) and φ(1020) channels respectively