31 research outputs found

    Ανάλυση δεδομένων δέσμης και κοσμικών μιονίων με τον ανιχνευτή ProtoDUNE στο εργαστήριο CERN

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    Το πείραμα DUNE φιλοξενείται από το Εθνικό Εργαστήριο Επιταχυντών Fermi στο Σικάγο, IL, ΗΠΑ, το μεγαλύτερο εργαστήριο φυσικής σωματιδίων και με τον μεγαλύτερο επιταχυντή στις Ηνωμένες Πολιτείες. Το πείραμα DUNE θα στείλει μια έντονη δέσμη νετρίνων 1300 χιλιομέτρων μέσω της γης από το Fermilab στη Νότια Ντακότα. Εκεί, περίπου 1.5 χιλιόμετρα υπογείως, ένας γιγαντιαίος ανιχνευτής νετρίνων υγρού-αργού 70 kt, θα αναλύσει πώς συμπεριφέρονται αυτά τα νετρίνα και αλληλεπιδρούν, μελετώντας τις ταλαντώσεις των νετρίνων μεταξύ των νετρίνων του μιονίου και του ηλεκτρονίου. Το ProtoDUNE-SP είναι ένα πρωτότυπο του μακρινού ανιχνευτή του DUNE και είναι σε δεξαμενή 7.2 x 6.9 x 6 μέτρων που περιέχει περίπου 800 τόνους υγρού αργού. Αυτός ο πρωτότυπος ανιχνευτής βρίσκεται στο εργαστήριο του CERN, στη Γενεύη της Ελβετίας, όπου έχει εκτεθεί σε αδρονικές δέσμες, σε δέσμη ποζιτρονίων αλλά και σε κοσμικά σωματίδια. Τα κοσμικά μιόνια είναι ένα ”πρότυπο κερί” και όλοι οι ανιχνευτές που βρίσκονται υπογείως ή στην επιφάνεια χρησιμοποιούν αυτά για μελέτες σταθερότητας και ανακατασκευής, αλλά και για μετρήσεις φυσικής. Θα περιγράψουμε και θα αναφερθούμε σε τέτοιες μελέτες που διεξάγονται στο πλαίσιο αυτής της MSc διατριβής, αποτελώντας τις πρώτες του είδους τους με τον ανιχνευτή ProtoDUNE-SP. Τέλος, θα παρουσιάσουμε συγκρίσεις κοσμικών μιονίων και γεγονότων δέσμης με τη χρήση μιας σύγχρονης ανακατασκευής ροής σωματιδίων (PandoraPFA) που εφαρμόζεται στο ProtoDUNE-SPThe DUNE experiment is hosted by Fermi National Accelerator Laboratory at Chicago, IL, USA, the largest particle physics and accelerator laboratory in the United States. The DUNE experiment will send an intense neutrino beam 1300 kilometers through the earth from Fermilab to South Dakota. There, about 1.5 kilometers underground, a gigantic 70 kT liquid-argon neutrino detector, will analyze how those neutrinos behave and interact, studying neutrino oscillations between muon and electron neutrinos. The ProtoDUNE-SP is a prototype of the DUNE far detector, and is a 7,2 x 6,9 x 6-meter tank containing about 800 tonnes of liquid argon. This prototype detector is located at the CERN laboratory, in Geneva, Switzerland, where it has been exposed to beams of electrons, pions, muons and cosmic particles. Cosmic muons is a “standard candle” and all underground, or surface, detectors use those for time stability and reconstruction studies, but also for physics measurements. We will describe and report on such studies conducted in the context of this MSc thesis, constituting the first of their kind with the ProDUNE-SP detector. We will also present comparisons of cosmic muon and beam induced events with the use of a state-of-the-art particle flow reconstruction (PandoraPFA) implemented in ProtoDUNE-SP. Finally, we will present prospects on future studies and on-going physics measurements

    Impaired renal function is associated with mortality and morbidity after endovascular abdominal aortic aneurysm repair

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    BackgroundRenal function may be associated with poor outcome following endovascular abdominal aortic aneurysm repair (EVAR), but this relationship has not been adequately investigated. The aim of this study is to evaluate the association of estimated glomerular filtration rate (eGFR) with cardiovascular events and all-cause mortality after EVAR.MethodsProspective cohort study of patients undergoing elective EVAR; eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration formula, and patients were divided in four groups (eGFR ≥90 mL/min/1.73 m2, group 1; 60-89, group 2; 30-59, group 3; <30, group 4). Composite end point consisted of death, nonfatal myocardial infarction, stroke, and vascular complications. Kaplan-Meier curves were constructed, and between-group comparisons were performed adjusted for variables that differed at baseline.ResultsA total of 383 patients (mean age, 69 ± 8 years; mean abdominal aortic aneurysm diameter, 6.2 ± 1.4 cm) were included. Over a mean follow-up of 34 ± 12 months, the following events occurred: 20 deaths (5.2%), 15 nonfatal myocardial infarctions (3.9%), 9 nonfatal strokes (2.3%), and 7 peripheral vascular complications (1.8%). Patients with an eGFR <30 had the highest mortality (35%) and incidence of complications (80%) as per the end point (P = .009 and P < .001, respectively). Adjusted Cox-regression analysis showed that a higher eGFR at baseline by 1 mL/min/1.73 m2 was associated with a 5% lower likelihood of complications as per the end point (P < .001; hazard ratio, 0.95; 95% confidence interval, 0.94-0.97) and a 6% lower likelihood of death (P < .001; hazard ratio, 0.94; 95% confidence interval, 0.92-0.97).ConclusionsImpaired renal function is associated with an increase in cardiovascular events and mortality following elective EVAR

    Suprarenal graft fixation in endovascular abdominal aortic aneurysm repair is associated with a decrease in renal function

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    IntroductionSuprarenal endograft fixation is routinely used in the endovascular repair of abdominal aortic aneurysms (EVAR) to enhance proximal endograft attachment but can be associated with an adverse outcome in renal function. This prospective study assessed the effect of suprarenal fixation on serum creatinine concentration and estimated glomerular filtration rate (eGFR), calculated by the Modified Diet in Renal Disease equation, 12 months after elective EVAR.MethodsPatients undergoing elective EVAR were divided into suprarenal vs infrarenal fixation groups matched for age, sex, smoking, and aneurysm diameter. Serum creatinine and eGFR were measured at baseline, 6, and 12 months.ResultsIncluded were 92 patients (two women) with a mean age of 71 ± 7 years, with 46 in each group. No device-related complications were noted. Serum creatinine did not differ significantly between groups at 6 (P = .24) or 12 (P = .08) months but significantly increased in the suprarenal group at 12 months (1.08 ± 0.36 to 1.16 ± 0.36 mg/dL; P < .001) vs baseline. The eGFR (mL/min/1.73 m2) did not differ significantly at baseline between the suprarenal (85 ± 27) and infrarenal (80 ± 28; P = .33) groups or at 6 months (88 ± 29 vs 77 ± 24, respectively; P = .07). At 12 months, the suprarenal group had a lower eGFR (73 ± 23) than the infrarenal group (84 ± 26; P = .027). The eGFR at 12 months showed a significant decrease in the suprarenal (80 ± 28 to 73 ± 23; P < .001) but not in the infrarenal group (85 ± 27 to 84 ± 26; P = .48). The drop in eGFR differed significantly at 12 months in the infrarenal vs the suprarenal (0.82 vs −6.94; P < .001) group. No patient progressed to end-stage renal disease or disclosed a drop in eGFR > 30%.ConclusionsIn contrast to previous studies, this study suggests that suprarenal endograft fixation in elective EVAR is associated with a drop in eGFR at 12 months

    Comparison of the impact of open and endovascular abdominal aortic aneurysm repair on renal function.

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    OBJECTIVE The impact of any intervention on renal function is a crucial determinant of outcome. Open (OR) and endovascular (EVAR) abdominal aortic aneurysm (AAA) repair can affect renal function during the short and longer term. This study aimed to directly compare the effect of those different types of aneurysm repair during a period of 2 years. METHODS This was a nested case-control study including patients undergoing either OR or EVAR of an infrarenal AAA. Three groups were included: OR, EVAR with suprarenal endograft fixation, and EVAR with infrarenal fixation. These were matched for age (within 2 years), sex, AAA size (within 1 cm), hypertension, smoking, and proximal neck diameter (within 5 mm). The primary end point was change in estimated glomerular filtration rate (eGFR) calculated by the Chronic Kidney Disease Epidemiology Collaboration formula at baseline, 6 months, 12 months, and 2 years. RESULTS A total of 225 patients were included [(45 ORs matched vs 90 suprarenal and 90 infrarenal fixation EVARs; 35 women (16%); age, 71 ± 8 years; AAA size, 6.4 ± 1 cm]. Groups did not differ significantly in terms of diabetes, hypercholesterolemia, or baseline eGFR (P = .89). On average, those undergoing OR lost a mean 5.39 mL/min/1.73 m(2) (P = .48) within 1 year and 5.49 units (P = .42) after 2 years. The suprarenal fixation patients lost 5.58 units (P = .002) after 1 year and 6.57 units (P = .001) after 2 years. Finally, the infrarenal fixation patients lost 0.53 unit (P = .74) after 1 year and 2.24 units (P = .22) after 2 years. CONCLUSIONS OR and suprarenal fixation EVAR are associated with significant declines in renal function during 2 years, in contrast to infrarenal EVAR fixation. The patterns of eGFR decline in OR and suprarenal fixation EVAR are not similar, suggesting different causal mechanisms

    Deep Underground Neutrino Experiment (DUNE), Far Detector Technical Design Report, Volume I Introduction to DUNE

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    International audienceThe preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE's physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology

    Deep Underground Neutrino Experiment (DUNE), Far Detector Technical Design Report, Volume II: DUNE Physics

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    The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay -- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. DUNE is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. Volume II of this TDR, DUNE Physics, describes the array of identified scientific opportunities and key goals. Crucially, we also report our best current understanding of the capability of DUNE to realize these goals, along with the detailed arguments and investigations on which this understanding is based. This TDR volume documents the scientific basis underlying the conception and design of the LBNF/DUNE experimental configurations. As a result, the description of DUNE's experimental capabilities constitutes the bulk of the document. Key linkages between requirements for successful execution of the physics program and primary specifications of the experimental configurations are drawn and summarized. This document also serves a wider purpose as a statement on the scientific potential of DUNE as a central component within a global program of frontier theoretical and experimental particle physics research. Thus, the presentation also aims to serve as a resource for the particle physics community at large

    Deep Underground Neutrino Experiment (DUNE) Near Detector Conceptual Design Report

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    International audienceThe Deep Underground Neutrino Experiment (DUNE) is an international, world-class experiment aimed at exploring fundamental questions about the universe that are at the forefront of astrophysics and particle physics research. DUNE will study questions pertaining to the preponderance of matter over antimatter in the early universe, the dynamics of supernovae, the subtleties of neutrino interaction physics, and a number of beyond the Standard Model topics accessible in a powerful neutrino beam. A critical component of the DUNE physics program involves the study of changes in a powerful beam of neutrinos, i.e., neutrino oscillations, as the neutrinos propagate a long distance. The experiment consists of a near detector, sited close to the source of the beam, and a far detector, sited along the beam at a large distance. This document, the DUNE Near Detector Conceptual Design Report (CDR), describes the design of the DUNE near detector and the science program that drives the design and technology choices. The goals and requirements underlying the design, along with projected performance are given. It serves as a starting point for a more detailed design that will be described in future documents

    DUNE Offline Computing Conceptual Design Report