29 research outputs found
TPB thickness and Quantum Efficiency measurements for the new ICARUS T600 light detection system in the SBN program.
Tetra-Phenyl-Butadiene (TPB) has been widely used in the last years in LAr experiments due to its property to convert VUV into visible light. To this purpose, a study of its property has been performed in order to obtain the best TPB coating on the PMT sensitive window for the new ICARUS T600 light detection system in the Short-Baseline Neutrino program at FNAL
Study on the TPB as wavelength shifter for the ICARUS T600 light detection system in the Fermilab SBN program
TPB thickness and Quantum Efficiency measurements for the new ICARUS T600 light detection system in the SBN program.
Timing properties of Hamamatsu R5912-MOD photomultiplier tube for the ICARUS T600 light detection system
The ICARUS T600 liquid argon time projection chamber (LAr-TPC) will operate at shallow depth as far detector for the Short Baseline Neutrino (SBN) program at FNAL. A new scintillation light detection system, with a time resolution of the order of the nanosecond, is required to distinguish the actual beam related events from the huge cosmic background. The chosen photomultiplier tube (PMT) model is the Hamamatsu R5912-MOD. This has an 8 in. diameter window made of borosilicate glass, 10 dynodes and a bialkali photo-cathode with platinum undercoating, suitable for cryogenic applications. The main timing characteristics of this PMT model â namely the absolute transit time vs. power supply, the transit time spread for light hitting different window places and for different PMT orientations with respect to the Earthâs magnetic field â have been evaluated in order to confirm the suitability of this PMT model to the requirements of the SBN program
Linearity and saturation properties of Hamamatsu R5912-MOD photomultiplier tube for the ICARUS T600 light detection system
The ICARUS T600 liquid argon time projection chamber (LAr-TPC) will operate at shallow depth as far detector for the Short Baseline Neutrino (SBN) program at FNAL. A new scintillation light detection system, based on 360 Hamamatsu R5912-MOD Photomultiplier Tubes (PMTs), will allow to distinguish the actual beam related events from the huge cosmic background. A fundamental parameter for the correct reconstruction of events is the linearity of the photon detection system. The main response characteristics of the adopted PMT model as a function of the incident light intensity was evaluated. A comparison of the behavior at room and at cryogenic temperature was also carried out. Results confirm the conformity of this PMT model to the requirements of the ICARUS T600 light detection system
Performance of large area PMTs at cryogenic temperatures for neutrino and rare event physics experiments
An evaluation of the behavior of three large cathode area photo-multiplier tubes, Hamamatsu R5912 Mod and R5912-02 Mod, and ETL 9357 KFLB, was carried out both at room temperature and immersed in liquid nitrogen, at a temperature of 77K. The main electrical and optical features of the devices were studied: signal shape, photo-cathode response uniformity, gain, linearity and dark count rate. An evaluation of the quantum efficiency was also made in the vacuum ultraviolet light region
Incidence, Risk Factors and Outcome of Pre-engraftment Gram-Negative Bacteremia after Allogeneic and Autologous Hematopoietic Stem Cell Transplantation: An Italian Prospective Multicenter Survey
Abstract
BACKGROUND:
Gram-negative bacteremia (GNB) is a major cause of illness and death after hematopoietic stem cell transplantation (HSCT), and updated epidemiological investigation is advisable.
METHODS:
We prospectively evaluated the epidemiology of pre-engraftment GNB in 1118 allogeneic HSCTs (allo-HSCTs) and 1625 autologous HSCTs (auto-HSCTs) among 54 transplant centers during 2014 (SIGNB-GITMO-AMCLI study). Using logistic regression methods. we identified risk factors for GNB and evaluated the impact of GNB on the 4-month overall-survival after transplant.
RESULTS:
The cumulative incidence of pre-engraftment GNB was 17.3% in allo-HSCT and 9% in auto-HSCT. Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the most common isolates. By multivariate analysis, variables associated with GNB were a diagnosis of acute leukemia, a transplant from a HLA-mismatched donor and from cord blood, older age, and duration of severe neutropenia in allo-HSCT, and a diagnosis of lymphoma, older age, and no antibacterial prophylaxis in auto-HSCT. A pretransplant infection by a resistant pathogen was significantly associated with an increased risk of posttransplant infection by the same microorganism in allo-HSCT. Colonization by resistant gram-negative bacteria was significantly associated with an increased rate of infection by the same pathogen in both transplant procedures. GNB was independently associated with increased mortality at 4 months both in allo-HSCT (hazard ratio, 2.13; 95% confidence interval, 1.45-3.13; P <.001) and auto-HSCT (2.43; 1.22-4.84; P = .01).
CONCLUSIONS:
Pre-engraftment GNB is an independent factor associated with increased mortality rate at 4 months after auto-HSCT and allo-HSCT. Previous infectious history and colonization monitoring represent major indicators of GNB.
CLINICAL TRIALS REGISTRATION:
NCT02088840
Deep Underground Neutrino Experiment (DUNE), Far Detector Technical Design Report, Volume I Introduction to DUNE
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 decayâthese 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