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Food for Thought: Dietary Intervention in a Rare Cause of Severe Ventilatory Failure
Get PDFPlastic bronchitis is a rare condition characterised by endobronchial cast formation. We report the case of a 53-year-old women who deteriorated following an elective bronchoscopy procedure. She developed refractory ventilatory failure and required repeated bronchoscopy, which identified thick tenacious casts as the cause of her airway compromise. She did not respond to conventional therapies including endoscopic clearance, mucolytic therapy and nebulised tissue plasminogen activator (TPA). Total parenteral nutrition and a fat-free enteral diet were instituted while the patient was on extracorporeal membrane oxygenation (ECMO), which led to substantial improvement in her condition and demonstrated the importance of dietary strategies in this case
Neutrinoless double beta decay search with the GERDA experiment
No full textThe Gerda experiment, located at the Laboratori Nazionali del Gran Sasso (LNGS), searches for the neutrinoless double beta decay of 76Ge. The experiment is using 36 kg of high-purity germanium detectors, simultaneously as
source and detector, deployed into ultra-pure cryogenic liquid argon. Gerda is one the leading experiments in the field, reporting the highest sensitivity on the half-life of 0νββ decay with 1.1 · 1026 yr, the lowest background index with 6 · 10−4 cts/(keV·kg·yr) and an excellent energy resolution of 0.12% (FWHM). The experimental setup, the analysis procedures and the latest results of Gerda are summarized in the present wor
Recent results on single vector boson plus jets production at CMS
No full textThe most recent results on the hadroproduction of an electroweak boson in association with one or more jets within the CMS experiment are presented. The cross section is studied differentially with respect to the transverse momentum and the angular correlation of the final state particles. Attention is given to the associated production of a vector boson plus flavour-tagged (b, c) jets. Comparison between data and different state-of-the-art theoretical predictions including (nextto)-leading-order corrections are presented as well
Micromegas chambers performance studies for the ATLAS upgrade
No full textThe MICRO MEsh GAseous Structure, micromegas (MM), are
highly innovative micro-pattern gas detectors, designed to achieve high spatial resolution (σx ∼ 100 μm) and high efficiency (>95%) in highly irradiated environments (φ ∼ 15 kHz/cm2). For this reason, these chambers were chosen as precision detectors for the upgrade of the ATLAS muon spectrometer (New Small Wheel project, NSW), in view of the expected increase of the luminosity at LHC for Run 3 and HL-LHC (High Lumi LHC) programme. Two identical NSW will be built to replace the innermost stations in the two forward regions of the ATLAS muon spectrometer. Each NSW will consists of two different detector technologies: MM and sTGC (small strip Thin Gap Chamber) to provide information both to the ATLAS trigger and to the track reconstruction. The NSW consists of 8 large sectors (LM) and 8 small sectors (SM). To ensure redundancy, each sector will consist of 2 MM chambers and two sTGCs with 4 layers each, for a total of 16 points per track. Four types of MM chambers called LM 1-2 and SM 1-2 are currently under construction, whose production is distributed among different countries: Italy (SM1), Germany (SM2), France (LM1), Greece and Russia (LM2). All the chambers will be trapezoidal in shape, with areas of 2–3 m2. Each MM chamber, composed of 4 reading layers, will provide information about the precision coordinate in ATLAS (η) and, through the two planes with stereo reading (±1.5 degrees), also about the azimuthal coordinate (φ). In this paper the validation procedures of the chambers will be shown as well as the results obtained on the first MM SM1 modules at the cosmic rays stand of the National Laboratories of Frascati
Studies on the optimization of the spark protection resistive layer in Small-pad MICROMEGAS detectors
No full textMotivated mainly by future detector upgrades at HL-LHC and at future colliders, the Small-pad resistive MICROMEGAS prototypes were designed to overcome the actual limitations of more standard strip resistive MICROMEGAS. In these new prototypes, small pads with a few mm2 area replace the readout strips to reduce the occupancy, and the spark protection resistive layer has been redesigned and optimized with different techniques to permit a safe behaviour of the detector, without efficiency loss, at rates of the order of tens MHz cm−2 over large surfaces
Search for exotic particles in multileptonic final states with the ATLAS detector
No full textThe search for exotic particles Beyond the Standard Model (BSM) is a major part of the ATLAS physics program. Due to the low number of Standard Model events in final states with large lepton multiplicity, searches in these final states allow to reject a substantial fraction of background providing a better signal-to-noise ratio. New physics (NP) events are searched for in several processes:
production of doubly charged Higgs bosons (H±±) and production of heavy neutral or charged leptons predicted, for instance in mechanisms like Type-III SeeSaw or LRSM models. BSM searches in multileptonic finale states using the pp collision data sample collected in the Run2 by the ATLAS experiment corresponding to 80.0 fb−1 of integrated luminosity at a centre-of-mass energy of 13 TeV are presented. Final states with same-sign leptons (only electrons and muons) are particularly interesting since they are affected by low Standard Model background. Searches are performed in final states which maximize the predicted production cross-section
Prospects for di-Higgs measurements in the b¯bγγ final state at the High-Luminosity LHC with the phase-II CMS detector
No full textThe prospects for the study of the production of a pair of Higgs bosons (HH), where one decays into two photons and the other one into a bottom quark-antiquark pair, are presented for a center-of-mass energy of 14 TeV at the
High-Luminosity LHC. The analysis is developed using a parametric simulation of the Phase-II upgraded CMS detector and optimized for an integrated luminosity of
3000 fb−1. The projected statistical sensitivity of this decay channel for the standard model HH signal is about 1.8σ, the highest among the decay channels considered
for HH searches. Projections are also presented for the measurement of the Higgs boson self-coupling λ3
A fast muon tagger method for Imaging Atmospheric Cherenkov Telescopes
No full textThe Cherenkov Telescope Array (CTA) will be the next major
observatory for Very High Energy (VHE) γ-ray astronomy. Its optical throughput calibration relies on muon Cherenkov rings. This work is aimed at developing a fast and efficient muon tagger at the camera level for the CTA telescopes. A novel technique to tag muons using the capabilities of silicon photomultiplier Compact High-Energy Camera CHEC-S, one of the design options for the camera of the Small Size Telescopes (SSTs), has been developed, studying and comparing different algorithms such as circle fitting, machine learning and simple pixel counting. Their performance in terms of efficiency and computation speed was investigated using simulations with varying levels of night sky background light. The application of the best performing method to the Large Size Telescope (LST) camera has been also studied, with the goal of improving the speed of the muon preselection
Searches for supersymmetric higgsinos with the ATLAS detector
No full textA search for supersymmetric partners of the Higgs and gauge bosons (charginos and neutralinos) is presented in this work, using the data from the ATLAS experiment collected at LHC. Considerations on the naturalness of the Higgs boson mass suggest that the two lightest neutralinos might be a mix of the partners of the Higgs boson and could have a similar mass. Using this scenario as a
reference, two analyses are presented. One has a final state with pairs of electrons or muons with low transverse momentums coming from the decay of the two lightest neutralinos, high missing transverse momentum generated by neutralinos which are non detectable, and an energetic jet coming from QCD initial state radiation. The second one is characterised by a final state with disappearing tracks, and high missing transverse momentum. Results are shown for the analysis obtained with 36 fb−1, and limits are set on the mass parameter of the higgsinos
ATLAS Pixel Detector during Run 2
No full textSilicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). During Run 2 of LHC the detector had to sustain many challenges in order to keep the performances
and quality of data taking constant in time, against the increasing instantaneous luminosity, increasing pile-up, and radiation damage. This work presents how the
operational parameters of the detectors were changed in order to keep the data acquisition, the occupancy, and the resolution evolution constant with time. The effects of the radiation damage on charge collection efficiency and their dependency with time are also presented