128 research outputs found
Modal analysis of a scale model of QD0
The last focusing magnets of the future Compact Linear Collider (CLIC) are critical elements needed to reach the desired luminosity. Designed to guide the nanometer sized focused beams, they need to be as stiff as possible to avoid any unwanted ground motion vibration amplification. Following our recent study concerning CLIC's ground motion mitigation techniques such as the active seismic isolator, the next step is to build a real scale prototype of the QD0. This mock-up is needed to validate experimentally the proposed control strategy. Such a prototype isn't yet available, hence this first study with a scale model of QD0. In this paper, modal analysis is used to analyze the dynamic characteristics of the structure of the prototype. This analysis identifies mode shapes, frequency and damping parameters. The purpose of this paper is to provide model verification by comparing experimental and theoretical modal analysis. The knowledge of these modes would later allow to validate experimentally ground motion vibration damping on that scale model of QD0, and finally on the real scale mock-up of QD0 by predicting the effect of design change
Concurrent trastuzumab with adjuvant radiotherapy in HER2-positive breast cancer patients: acute toxicity analyses from the French multicentric study
Background: Trastuzumab (T) combined with chemotherapy has been recently shown to improve outcome in HER2-positive breast cancer (BC). The aim of this study was to evaluate the toxic effects of concurrent radiation therapy (RT) and T administration in the adjuvant setting. Patients and methods: Data of 146 patients with stages II-III HER2-positive BC were recorded. Median age was 46 years. In all, 32 (23%) and 114 (77%) patients received a weekly and a 3-week T schedule, respectively. A median dose of 50 Gy was delivered after surgery. Internal mammary chain (IMC) was irradiated in 103 (71%) patients. Results: Grade >2 dermatitis and esophagitis were noted in 51% and 12%, respectively. According to the Common Toxicity Criteria v3.0 scale and HERA (HERceptin Adjuvant) trial criteria, respectively, 10% and 6% of the patients had a grade ≥2 of left ventricular ejection fraction (LVEF) decrease after RT. Multivariate analyses revealed two independent prognostic factors: weekly T administration (for LVEF decrease) and menopausal status (for dermatitis). Higher level of T cumulative dose (>1600 mg) was only borderline of statistical significance for acute esophagitis toxicity. Conclusion: We showed that weekly concurrent T and RT are feasible in daily clinical practice with, however, a decrease of LVEF. Cardiac volume sparing and patient selections for IMC irradiation are highly recommended. Longer follow-up is warranted to evaluate late toxic effect
Concurrent trastuzumab with adjuvant radiotherapy in HER2-positive breast cancer patients: acute toxicity analyses from the French multicentric study
BACKGROUND: Trastuzumab (T) combined with chemotherapy has been recently shown to improve outcome in HER2-positive breast cancer (BC). The aim of this study was to evaluate the toxic effects of concurrent radiation therapy (RT) and T administration in the adjuvant setting.
PATIENTS AND METHODS: Data of 146 patients with stages II-III HER2-positive BC were recorded. Median age was 46 years. In all, 32 (23%) and 114 (77%) patients received a weekly and a 3-week T schedule, respectively. A median dose of 50 Gy was delivered after surgery. Internal mammary chain (IMC) was irradiated in 103 (71%) patients.
RESULTS: Grade >2 dermatitis and esophagitis were noted in 51% and 12%, respectively. According to the Common Toxicity Criteria v3.0 scale and HERA (HERceptin Adjuvant) trial criteria, respectively, 10% and 6% of the patients had a grade >/=2 of left ventricular ejection fraction (LVEF) decrease after RT. Multivariate analyses revealed two independent prognostic factors: weekly T administration (for LVEF decrease) and menopausal status (for dermatitis). Higher level of T cumulative dose (>1600 mg) was only borderline of statistical significance for acute esophagitis toxicity.
CONCLUSION: We showed that weekly concurrent T and RT are feasible in daily clinical practice with, however, a decrease of LVEF. Cardiac volume sparing and patient selections for IMC irradiation are highly recommended. Longer follow-up is warranted to evaluate late toxic effects
Impact of cross-section uncertainties on supernova neutrino spectral parameter fitting in the Deep Underground Neutrino Experiment
Reconstruction of interactions in the ProtoDUNE-SP detector with Pandora
The Pandora Software Development Kit and algorithm libraries provide pattern-recognition logic essential to the reconstruction of particle interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at ProtoDUNE-SP, a prototype for the Deep Underground Neutrino Experiment far detector. ProtoDUNE-SP, located at CERN, is exposed to a charged-particle test beam. This paper gives an overview of the Pandora reconstruction algorithms and how they have been tailored for use at ProtoDUNE-SP. In complex events with numerous cosmic-ray and beam background particles, the simulated reconstruction and identification efficiency for triggered test-beam particles is above 80% for the majority of particle type and beam momentum combinations. Specifically, simulated 1 GeV/c charged pions and protons are correctly reconstructed and identified with efficiencies of 86.1 ± 0.6 % and 84.1 ± 0.6 %, respectively. The efficiencies measured for test-beam data are shown to be within 5% of those predicted by the simulation
Highly-parallelized simulation of a pixelated LArTPC on a GPU
The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 103 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype
Identification and reconstruction of low-energy electrons in the ProtoDUNE-SP detector
Measurements of electrons from νe interactions are crucial for the Deep Underground Neutrino Experiment (DUNE) neutrino oscillation program, as well as searches for physics beyond the standard model, supernova neutrino detection, and solar neutrino measurements. This article describes the selection and reconstruction of low-energy (Michel) electrons in the ProtoDUNE-SP detector. ProtoDUNE-SP is one of the prototypes for the DUNE far detector, built and operated at CERN as a charged particle test beam experiment. A sample of low-energy electrons produced by the decay of cosmic muons is selected with a purity of 95%. This sample is used to calibrate the low-energy electron energy scale with two techniques. An electron energy calibration based on a cosmic ray muon sample uses calibration constants derived from measured and simulated cosmic ray muon events. Another calibration technique makes use of the theoretically well-understood Michel electron energy spectrum to convert reconstructed charge to electron energy. In addition, the effects of detector response to low-energy electron energy scale and its resolution including readout electronics threshold effects are quantified. Finally, the relation between the theoretical and reconstructed low-energy electron energy spectra is derived, and the energy resolution is characterized. The low-energy electron selection presented here accounts for about 75% of the total electron deposited energy. After the addition of lost energy using a Monte Carlo simulation, the energy resolution improves from about 40% to 25% at 50 MeV. These results are used to validate the expected capabilities of the DUNE far detector to reconstruct low-energy electrons
Performance study of a 3 x 1 x 1 m(3) dual phase liquid Argon Time Projection Chamber exposed to cosmic rays
This work would not have been possible without the support of the Swiss National Science Foundation, Switzerland; CEA and CNRS/IN2P3, France; KEK and the JSPS program, Japan; Ministerio de Ciencia e Innovacion in Spain under grants FPA2016-77347-C2, SEV-2016-0588 and MdM-2015-0509, Comunidad de Madrid, the CERCA program of the Generalitat de Catalunya and the fellowship (LCF/BQ/DI18/11660043) from "La Caixa" Foundation (ID 100010434); the Programme PNCDI III, CERN-RO, under Contract 2/2020, Romania; the U.S. Department of Energy under Grant No. DE-SC0011686. This project has received funding from the European Union's Horizon 2020 Research and Innovation program under Grant Agreement no. 654168. The authors are also grateful to the French government operated by the National Research Agency (ANR) for the LABEX Enigmass, LABEX Lyon Institute of Origins (ANR-10-LABX-0066) of the Universite de Lyon for its financial support within the program "Investissements d'Avenir" (ANR-11-IDEX-0007).We report the results of the analyses of the cosmic ray data collected with a 4 tonne (3x1x1 m(3)) active mass (volume) Liquid Argon Time-Projection Chamber (TPC) operated in a dual-phase mode. We present a detailed study of the TPC's response, its main detector parameters and performance. The results are important for the understanding and further developments of the dual-phase technology, thanks to the verification of key aspects, such as the extraction of electrons from liquid to gas and their amplification through the entire one square metre readout plain, gain stability, purity and charge sharing between readout views.Swiss National Science Foundation (SNSF)French Atomic Energy CommissionCentre National de la Recherche Scientifique (CNRS)High Energy Accelerator Research Organization (KEK)Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT)Japan Society for the Promotion of ScienceSpanish Government FPA2016-77347-C2
SEV-2016-0588MdM-2015-0509Comunidad de MadridCERCA program of the Generalitat de CatalunyaLa Caixa Foundation LCF/BQ/DI18/11660043
100010434Programme PNCDI III, RomaniaCERN-RO, Romania 2/2020United States Department of Energy (DOE) SC0011686European Commission 654168Universite de Lyon ANR-10-LABX-0066
ANR-11-IDEX-000
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