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A semi-empirical model is presented for the excitation of collective nuclear resonances induced by pions on nuclei in the
(1232) energy region. The physical features of the collective states have ...been extracted according to the model by fitting data from a collection of resonant
-nucleus elastic scattering cross-sections. The contributions to the total binding energy and to the width of a collective state per each additional nucleon involved in the resonance have been extracted. The interaction between the collective resonances and the surrounding nuclear medium is discussed.
Measurement of the in-medium modifications of the Δ resonance, signatures of the excitation of nuclear collective states and the first experimental evidence for a thermal emission of photons have ...been obtained from the analysis of new π±4He data at Tπ 106 MeV at PAINUC experiment.
Abstract Objectives This study sought to compare myocardial scars depicted by computed tomography (CT) with electrical features from electro-anatomic mapping (EAM), assessing the potential role of CT ...integration in ventricular tachycardia (VT) and radiofrequency catheter ablation (RFCA) procedures. Background Imaging-based characterization of VT myocardial substrate is required to plan EAM and, potentially, to guide RFCA. Methods Forty-two consecutive patients, 35 of whom had implantable cardioverter-defibrillator, all referred for VT RFCA, underwent pre-procedural CT including an angiographic and a 10-min delayed-enhancement scan. Segmental comparison between scars segmented from CT and low voltages (bipolar voltages <1.5 mV; unipolar voltages <8 mV), late potentials, and RF ablation points on EAM, was carried out. In a subset of 16 consecutive patients, a further point-by-point analysis was performed: a CT-derived 3-dimensional structure including heart anatomy and myocardial scars was integrated with EAM for quantitative comparison. Results CT scans identified scars in 39 patients and defined left ventricular wall involvement and mural distribution. Overall segmental concordance between CT and EAM was good (κ = 0.536) despite the presence of implantable cardioverter-defibrillator, scar etiologies, and mural distribution. CT identified segments characterized by low voltages with good sensitivity (76%), good specificity (86%), and very high negative predictive value (95%). Late potentials and RF ablation points fell on scarred segments identified from CT in 79% and 81% of cases, respectively. Point-by-point quantitative comparison revealed good correlation between the average area of scar detected at CT and at bipolar mapping (CT = 4,901 mm2 , bipolar voltages-EAM = 4,070 mm2 ; R = 0.78; p < 0.0001). In this study, 70% and 84% of low-amplitude bipolar points were mapped at a maximum distance of 5 mm and 10 mm from CT-segmented scar, respectively. Conclusions CT with delayed-enhancement provides a 3-dimensional characterization of VT scar substrate together with a detailed anatomic model of the heart. This information may offer assistance to plan EAM and RFCA procedures and is potentially suitable for EAM-imaging integration.
In the COMPASS experiment, under construction at CERN, about 23000 channels of MWPCs will be used. The very high rate of the muon and hadron beams, and the consequently high trigger rate, require ...front-end electronics with a new conceptual design. A new MWPC front-end electronics that fulfills the main COMPASS requirement to have a fast DAQ with a minimum dead-time has been designed and tested. The scheme of the new, very low dead-time front-end electronics will be described; the results of the detector commissioning of the summer 2000 run, using a reduced set-up equipped with the running electronics will be described. Installation of the COMPASS detectors is to start in the spring of 2001, and production running is foreseen for the summer of 2001.
Two-prong πHe interactions at 106 MeV Angelov, N.; Baginyan, S.; Balestra, F. ...
The European physical journal. A, Hadrons and nuclei,
12/2007, Letnik:
34, Številka:
3
Journal Article
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