Istituto Nazionale di Fisica Nucleare, Centro Nazionale Analisi Fotogrammi

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A search is performed for Higgs bosons decaying into invisible final states, produced in association with a Z0 boson in e+e− collisions at energies between 183 and 209 GeV. The search is based on data samples collected by the OPAL detector at LEP corresponding to an integrated luminosity of about 660 pb−1. The analysis aims to select events containing the hadronic decay products of the Z0 boson and large missing momentum, as expected from Higgs boson decay into a pair of stable weakly interacting neutral particles, such as the lightest neutralino in the Minimal Supersymmetric Standard Model. The same analysis is applied to a search for nearly invisible Higgs boson cascade decays into stable weakly interacting neutral particles. No excess over the expected background from Standard Model processes is observed. Limits on the production of invisibly decaying Higgs bosons produced in association with a Z0 boson are derived. Assuming a branching ratio BR(h0→invisible)=1, a lower limit of 108.2 GeV is placed on the Higgs boson mass at the 95% confidence level. Limits on the production of nearly invisibly decaying Higgs bosons are also obtained.

We derive the Schrödinger equation for a spinless charged particle constrained to move on a curved surface in the presence of an electric and magnetic field. The particle is confined on the surface using a thin-layer procedure, which gives rise to the well-known geometric potential. The electric and magnetic fields are included via the four potential. We find that there is no coupling between the fields and the surface curvature and that, with a proper choice of the gauge, the surface and transverse dynamics are exactly separable. Finally, we derive an analytic form of the Hamiltonian for spherical, cylindrical, and toroidal surfaces.

Particle physics has an ambitious and broad experimental programme for the coming decades. This programme requires large investments in detector hardware, either to build new facilities and experiments, or to upgrade existing ones. Similarly, it requires commensurate investment in the R&D of software to acquire, manage, process, and analyse the shear amounts of data to be recorded. In planning for the HL-LHC in particular, it is critical that all of the collaborating stakeholders agree on the software goals and priorities, and that the efforts complement each other. In this spirit, this white paper describes the R&D activities required to prepare for this software upgrade.

Abstract The recent years witnessed an unprecedented enhancement in improved functionality materials and in the sophistication of solution‐based device fabrication techniques. Such significant advancements lead to unexpected and effective opportunities for the utilization of solution‐grown organic materials and perovskites in the detection of ionizing radiation. This review presents an updated overview of the recently reported top performing and more innovative organic/perovskite‐based X‐ray detectors, providing a comparison and a critical discussion on the different materials’ properties and performance. Solution‐growth methods that allow to obtain detector grade electronic materials are discussed, focusing on the growth both of single crystals and of thin/thick films and foreseeing the implementation of large‐area, organic/hybrid‐, and perovskite‐based radiation detectors. Insights into the X‐ray detection mechanisms are provided, detailing the fundamental processes involved in the charge collection and in the photoconductive gain model, together with the typical figures of merit that describe radiation detector performance.

The synthesis of a series of heterometallic rings and chains is reported. The family is based on the octanuclear cages of general formula [H(2)NR(2)][M(7)M'F(8)(O(2)CR')(16)], where M is a trivalent metal (Cr, Fe, V, Al, Ga or In), M' is a divalent metal (Mn, Fe, Co, Ni, Mg, Zn, Cd), R is a linear alkyl chain and O(2)CR' is one of around twenty carboxylates. Other members of the family with nonametallic and decametallic cores are described, and some new physics is outlined, including initial investigations of the proposed application of [Cr(7)Ni] rings as Qubits in quantum information processing.

BACKGROUND: In 2011, the European Directorate for the Quality of Medicines & Healthcare of the Council of Europe launched a 3-year collaborative project to address the organ shortage and improve access to transplant health services in Council of Europe member states in the Black Sea area (Armenia, Azerbaijan, Bulgaria, Georgia, Moldova, Romania, Turkey, Ukraine, and the Russian Federation) through the development of safe and ethical donation and transplantation programs. OBJECTIVE: Support the development of donation and transplantation programs through close interstate cooperation between national health organizations and relevant stakeholders. METHODOLOGY: Several work packages (WP) were established: WP1, project coordination (European Directorate for the Quality of Medicines & Healthcare); WP2, development and implementation of an effective legislative and financial framework (Czech Republic and France); WP3, establishment of National Transplant Authorities (Italy and Portugal); and WP4, clinical practices (DTI Foundation). Data collection, surveys, and expert visits allowed for the collection of first-hand information from each participant country at national, regional, and hospital levels. RESULTS: Data analysis showed the positive impact of the project represented by a tendency to increase the total donation rates (per million people) in the participant countries (2011 vs 2013): Azerbaijan, +7.3; Armenia, -0.7; Georgia, +3.3; Bulgaria, +0.9; Moldova, +2.5; Ukraine:, +0.8; Romania, +2.3; and Turkey, +2.7. CONCLUSIONS: Increases in total donation rates are the result of a number of initiatives in the Black Sea area, including the stepwise implementation of legislative, organizational and institutional country-specific recommendations tailored by the CoE, efforts of the respective Ministries of Health in each country and synergism with other European projects in the region. These countries should invest further in implementing the recommendations that emerged from this project to improve their organ donation and transplantation programs and progress toward self-sufficiency.

Abstract Studies on the interactions between SARS‐CoV‐2 and humoral immunity are fundamental to elaborate effective therapies including vaccines. We used polychromatic flow cytometry, coupled with unsupervised data analysis and principal component analysis (PCA), to interrogate B cells in untreated patients with COVID‐19 pneumonia. COVID‐19 patients displayed normal plasma levels of the main immunoglobulin classes, of antibodies against common antigens or against antigens present in common vaccines. However, we found a decreased number of total and naïve B cells, along with decreased percentages and numbers of memory switched and unswitched B cells. On the contrary, IgM + and IgM − plasmablasts were significantly increased. In vitro cell activation revealed that B lymphocytes showed a normal proliferation index and number of dividing cells per cycle. PCA indicated that B‐cell number, naive and memory B cells but not plasmablasts clustered with patients who were discharged, while plasma IgM level, C‐reactive protein, D‐dimer, and SOFA score with those who died. In patients with pneumonia, the derangement of the B‐cell compartment could be one of the causes of the immunological failure to control SARS‐Cov2, have a relevant influence on several pathways, organs and systems, and must be considered to develop vaccine strategies.

We study the behavior of the string tension in the SU(3) lattice pure-gauge theory close to the deconfining critical point. We find very large correlation lengths, increasing with the lattice size. This result is strongly suggestive of a second-order phase transition, and excludes the presence of a strong first-order transition.

Some theoretical issues related to the problem of quantifying local predictability of atmospheric flow and the generation of perturbations for ensemble forecasts are investigated in the Lorenz system. A periodic orbit analysis and the study of the properties of the associated tangent linear equations are performed. In this study a set of vectors are found that satisfy Oseledec theorem and reduce to Floquet eigenvectors in the particular case of a periodic orbit. These vectors, called Lyapunov vectors, can be considered the generalization to aperiodic orbits of the normal modes of the instability problem and are not necessarily mutually orthogonal. The relation between singular vectors and Lyapunov vectors is clarified, and transient or asymptotic error growth properties are investigated. The mechanism responsible for super-Lyapunov growth is shown to be related to the nonorthogonality of Lyapunov vectors. The leading Lyapunov vectors, as defined here, as well as the asymptotic final singular vectors, are tangent to the attractor, while the leading initial singular vectors, in general, point away from it. Perturbations that are on the attractor and maximize growth should be considered in meteorological applications such as ensemble forecasting and adaptive observations. These perturbations can be found in the subspace of the leading Lyapunov vectors.

In this work, a flexible and extensive digital platform for Smart Homes is presented, exploiting the most advanced technologies of the Internet of Things, such as Radio Frequency Identification, wearable electronics, Wireless Sensor Networks, and Artificial Intelligence. Thus, the main novelty of the paper is the system-level description of the platform flexibility allowing the interoperability of different smart devices. This research was developed within the framework of the operative project HABITAT (Home Assistance Based on the Internet of Things for the Autonomy of Everybody), aiming at developing smart devices to support elderly people both in their own houses and in retirement homes, and embedding them in everyday life objects, thus reducing the expenses for healthcare due to the lower need for personal assistance, and providing a better life quality to the elderly users.

Abstract Materials and technology development for designing innovative and efficient X‐ray radiation detectors is of utmost importance for a wide range of applications ranging from security to medical imaging. Here, highly sensitive direct X‐ray detectors based on novel cesium (Cs)‐based triple cation mixed halide perovskite thin films are reported. Despite being in a thin film form, the devices exhibit a remarkably high X‐ray sensitivity of (3.7 ± 0.1) µC Gy −1 cm −2 under short‐circuit conditions. At a small reverse bias of 0.4 V, the sensitivity further increases by orders of magnitude reaching a record value of (97 ± 1) µC Gy −1 cm −2 which surpasses state‐of‐the‐art inorganic large‐area detectors (a‐Se and poly‐CZT). Based on detailed structural, electrical, and spectroscopic investigations, the exceptional sensitivity of the triple cation Cs perovskite is attributed to its high ambipolar mobility‐lifetime product as well as to the formation of a pure stable perovskite phase with a low degree of energetic disorder, due to an efficient solution‐based alloying of individual n‐ and p‐type perovskite semiconductors.

In this paper we propose a distributed architecture to provide machine learning practitioners with a set of tools and cloud services that cover the whole machine learning development cycle: ranging from the models creation, training, validation and testing to the models serving as a service, sharing and publication. In such respect, the DEEP-Hybrid-DataCloud framework allows transparent access to existing e-Infrastructures, effectively exploiting distributed resources for the most compute-intensive tasks coming from the machine learning development cycle. Moreover, it provides scientists with a set of Cloud-oriented services to make their models publicly available, by adopting a serverless architecture and a DevOps approach, allowing an easy share, publish and deploy of the developed models.

We present iron and $α$ element (Mg, Ca, Ti) abundances for a sample of 15 Red Giant Branch stars belonging to the main body of the Sagittarius dwarf Spheroidal galaxy. Abundances have been obtained from spectra collected using the high resolution spectrograph FLAMES-UVES mounted at the VLT. Stars of our sample have a mean metallicity of [Fe/H]=-0.41$\pm$0.20 with a metal poor tail extending to [Fe/H]=-1.52. The $α$ element abundance ratios are slightly subsolar for metallicities higher than [Fe/H]\gtsima-1, suggesting a slow star formation rate. The [$α$/Fe] of stars having [Fe/H]$

MoEDAL is designed to identify new physics in the form of long-lived highly ionizing particles produced in high-energy LHC collisions. Its arrays of plastic nuclear-track detectors and aluminium trapping volumes provide two independent passive detection techniques. We present here the results of a first search for magnetic monopole production in 13 TeV proton-proton collisions using the trapping technique, extending a previous publication with 8 TeV data during LHC Run 1. A total of 222 kg of MoEDAL trapping detector samples was exposed in the forward region and analyzed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges exceeding half the Dirac charge are excluded in all samples and limits are placed for the first time on the production of magnetic monopoles in 13 TeV pp collisions. The search probes mass ranges previously inaccessible to collider experiments for up to five times the Dirac charge.

Abstract Organic semiconductor materials exhibit a great potential for the realization of large-area solution-processed devices able to directly detect high-energy radiation. However, only few works investigated on the mechanism of ionizing radiation detection in this class of materials, so far. In this work we investigate the physical processes behind X-ray photoconversion employing bis-(triisopropylsilylethynyl)-pentacene thin-films deposited by bar-assisted meniscus shearing. The thin film coating speed and the use of bis-(triisopropylsilylethynyl)-pentacene:polystyrene blends are explored as tools to control and enhance the detection capability of the devices, by tuning the thin-film morphology and the carrier mobility. The so-obtained detectors reach a record sensitivity of 1.3 · 10 4 µC/Gy·cm 2 , the highest value reported for organic-based direct X-ray detectors and a very low minimum detectable dose rate of 35 µGy/s. Thus, the employment of organic large-area direct detectors for X-ray radiation in real-life applications can be foreseen.

The MoEDAL experiment is designed to search for magnetic monopoles and other highly-ionising particles produced in high-energy collisions at the LHC. The largely passive MoEDAL detector, deployed at Interaction Point 8 on the LHC ring, relies on two dedicated direct detection techniques. The first technique is based on stacks of nucleartrack detectors with surface area ~18m2, sensitive to particle ionisation exceeding a high threshold. These detectors are analysed offline by optical scanning microscopes. The second technique is based on the trapping of charged particles in an array of roughly 800 kg of aluminium samples. These samples are monitored offline for the presence of trapped magnetic charge at a remote superconducting magnetometer facility. We present here the results of a search for magnetic monopoles using a 160 kg prototype MoEDAL trapping detector exposed to 8TeV proton-proton collisions at the LHC, for an integrated luminosity of 0.75 fb–1. No magnetic charge exceeding 0:5g D (where g D is the Dirac magnetic charge) is measured in any of the exposed samples, allowing limits to be placed on monopole production in the mass range 100 GeV≤ m ≤ 3500 GeV. Model-independent cross-section limits are presented in fiducial regions of monopole energy and direction for 1g D ≤ |g| ≤ 6g D, and model-dependent cross-section limits are obtained for Drell-Yan pair production of spin-1/2 and spin-0 monopoles for 1g D ≤ |g| ≤ 4g D. Under the assumption of Drell-Yan cross sections, mass limits are derived for |g| = 2g D and |g| = 3g D for the first time at the LHC, surpassing the results from previous collider experiments.

This paper describes the achievements of the H2020 project INDIGO-DataCloud. The project has provided e-infrastructures with tools, applications and cloud framework enhancements to manage the demanding requirements of scientific communities, either locally or through enhanced interfaces. The middleware developed allows to federate hybrid resources, to easily write, port and run scientific applications to the cloud. In particular, we have extended existing PaaS (Platform as a Service) solutions, allowing public and private e-infrastructures, including those provided by EGI, EUDAT, and Helix Nebula, to integrate their existing services and make them available through AAI services compliant with GEANT interfederation policies, thus guaranteeing transparency and trust in the provisioning of such services. Our middleware facilitates the execution of applications using containers on Cloud and Grid based infrastructures, as well as on HPC clusters. Our developments are freely downloadable as open source components, and are already being integrated into many scientific applications.

We report on real molecular complexes and propose strategies that explore the possibility of implementation of specific quantum computation architectures with molecular spin systems. We focus on Cr3+ carboxylate derivatives and use the Loss-DiVincenzo scheme as reference.