A large prototype of 1.3m3 was designed and built as a demonstrator of the semi-digital hadronic calorimeter (SDHCAL) concept proposed for the future ILC experiments. The prototype is a sampling ...hadronic calorimeter of 48 units. Each unit is built of an active layer made of 1m2 Glass Resistive Plate Chamber(GRPC) detector placed inside a cassette whose walls are made of stainless steel. The cassette contains also the electronics used to read out the GRPC detector. The lateral granularity of the active layer is provided by the electronics pick-up pads of 1cm2 each. The cassettes are inserted into a self-supporting mechanical structure built also of stainless steel plates which, with the cassettes walls, play the role of the absorber. The prototype was designed to be very compact and important efforts were made to minimize the number of services cables to optimize the efficiency of the Particle Flow Algorithm techniques to be used in the future ILC experiments. The different components of the SDHCAL prototype were studied individually and strict criteria were applied for the final selection of these components. Basic calibration procedures were performed after the prototype assembling. The prototype is the first of a series of new-generation detectors equipped with a power-pulsing mode intended to reduce the power consumption of this highly granular detector. A dedicated acquisition system was developed to deal with the output of more than 440000 electronics channels in both trigger and triggerless modes. After its completion in 2011, the prototype was commissioned using cosmic rays and particles beams at CERN.
Next-generation imaging (NGI) tests, such as choline PET/CT and PSMA PET, have shown to increase sensitivity in the detection of nodal and metastatic disease in prostate cancer. However, their use ...implies an increase in diagnostic costs compared to conventional imaging (CI) tests such as CT and bone scan. The aim of our study was to determine which diagnostic pathway is more cost-effective in high-risk prostate cancer.
Cost-effectiveness analysis of the available imaging tests (CI, Choline/PSMA PET) for the staging of high-risk prostate cancer. Sensitivity and specificity were estimated based on published evidence, and costs were collected from the Management Department. In order to carry out a cost-effectiveness analysis, five diagnostic pathways were proposed estimating the accurate diagnoses.
PSMA PET was the most accurate diagnostic option. The CI diagnostic workup was the most economical and CI+PSMA the most expensive. Analyzing the diagnostic cost-effectiveness ratio, CI+PSMA proved to be the most expensive (€5627.30 per correct diagnosis) followed by PET PSMA (€4987.11), choline (€4599.84) and CI (€4444.22).
PSMA PET is the most accurate strategy in staging distant disease in patients with high-risk prostate cancer. Radiotracer uptake tests such as CI have been shown to be the most cost-effective option, followed by choline and PSMA.
Las pruebas de imagen de nueva generación, como PET-colina y PET-PSMA, han demostrado incrementar la sensibilidad tanto en la detección de enfermedad ganglionar como metastásica en el cáncer de próstata. Su uso no obstante implica un aumento de costes diagnósticos frente a pruebas convencionales (PPCC:TC y gammagrafía). El objetivo de nuestro trabajo fue determinar que opción diagnóstica es más coste-efectivo en el cáncer de próstata de alto riesgo.
Estudio de decisión de coste para la estadificación de cáncer de próstata de alto riesgo según las pruebas de imagen disponibles: PPCC, PET-Colina y PET-PSMA. Se estimó su sensibilidad y especificidad en base a la evidencia publicada y se recopilaron los costes necesarios desde el departamento de gestión. Se plantearon cinco líneas de diagnóstico posibles estimando los diagnósticos realizados de forma correcta para posteriormente realizar un análisis de coste efectividad.
El PET PSMA fue la opción diagnóstica más certera. La línea diagnóstica de PPCC fue la más económica y PPCC+PET PSMA la más costosa. Al analizar la relación coste-efectividad diagnóstica, PPCC+PET PSMA resultó ser la más costosa (5627,30€ por cada diagnóstico correcto) seguida de PET PSMA (4987,11€), PET colina (4599,84€) y pruebas convencionales (4444,22€).
El PET PSMA es la estrategia más precisa en la estadificación de la enfermedad a distancia en pacientes con cáncer de próstata de alto riesgo. Las pruebas de captación de radiofármacos como las PPCC han mostrado ser la opción más rentable, seguidas por el PET colina y el PET PSMA.
Abstract
A neural network for software compensation was developed for the highly granular CALICE Analogue Hadronic Calorimeter (AHCAL). The neural network uses spatial and temporal event information ...from the AHCAL and energy information, which is expected to improve sensitivity to shower development and the neutron fraction of the hadron shower. The neural network method produced a depth-dependent energy weighting and a time-dependent threshold for enhancing energy deposits consistent with the timescale of evaporation neutrons. Additionally, it was observed to learn an energy-weighting indicative of longitudinal leakage correction. In addition, the method produced a linear detector response and outperformed a published control method regarding resolution for every particle energy studied.
A new design of highly granular hadronic calorimeter using Glass Resistive Plate Chambers (GRPCs) with embedded electronics has been proposed for the future International Linear Collider (ILC) ...experiments. It features a 2-bit threshold semi-digital read-out. Several GRPC prototypes with their electronics have been successfully built and tested in pion beams. The design of these detectors is presented along with the test results on efficiency, pad multiplicity, stability and reproducibility.
Abstract
The CALICE Semi-Digital Hadron Calorimeter technological
prototype completed in 2011 is a sampling calorimeter using Glass
Resistive Plate Chamber (GRPC) detectors as the active medium. This
...technology is one of the two options proposed for the hadron
calorimeter of the International Large Detector for the
International Linear Collider. The prototype was exposed in 2015 to
beams of muons, electrons, and pions of different energies at the
CERN Super Proton Synchrotron. The use of this technology for
future experiments requires a reliable simulation of its response
that can predict its performance. GEANT4 combined with a
digitization algorithm was used to simulate the prototype. It
describes the full path of the signal: showering, gas avalanches,
charge induction, and hit triggering. The simulation was tuned using
muon tracks and electromagnetic showers for accounting for detector
inhomogeneity and tested on hadronic showers collected in the test
beam. This publication describes developments of the digitization
algorithm. It is used to predict the stability of the detector
performance against various changes in the data-taking conditions,
including temperature, pressure, magnetic field, GRPC width
variations, and gas mixture variations. These predictions are
confronted with test beam data and provide an attempt to explain the
detector properties. The data-taking conditions such as temperature
and potential detector inhomogeneities affect energy density
measurements but have small impact on detector efficiency.
Application Specific Integrated Circuits, ASICs, similar to those envisaged for the readout electronics of the central calorimeters of detectors for a future lepton collider have been exposed to ...high-energy electromagnetic showers. A salient feature of these calorimeters is that the readout electronics will be embedded into the calorimeter layers. In this article it is shown that interactions of shower particles in the volume of the readout electronics do not alter the noise pattern of the ASICs. No signal at or above the MIP level has been observed during the exposure. The upper limit at the 95% confidence level on the frequency of fake signals is smaller than
1
×
10
−
5
for a noise threshold of about 60% of a MIP. For ASICs with similar design to those which were tested, it can thus be largely excluded that the embedding of the electronics into the calorimeter layers compromises the performance of the calorimeters.
Combined measurements of the production and decay rates of the Higgs boson, as well as its couplings to vector bosons and fermions, are presented. The analysis uses the LHC proton–proton collision ...data set recorded with the CMS detector in 2016 at
s
=
13
Te
, corresponding to an integrated luminosity of 35.9
fb
-
1
. The combination is based on analyses targeting the five main Higgs boson production mechanisms (gluon fusion, vector boson fusion, and associated production with a
W
or
Z
boson, or a top quark-antiquark pair) and the following decay modes:
H
→
γ
γ
,
Z
Z
,
W
W
,
τ
τ
,
b
b
, and
μ
μ
. Searches for invisible Higgs boson decays are also considered. The best-fit ratio of the signal yield to the standard model expectation is measured to be
μ
=
1.17
±
0.10
, assuming a Higgs boson mass of
125.09
Ge
. Additional results are given for various assumptions on the scaling behavior of the production and decay modes, including generic parametrizations based on ratios of cross sections and branching fractions or couplings. The results are compatible with the standard model predictions in all parametrizations considered. In addition, constraints are placed on various two Higgs doublet models.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A search for invisible decays of a Higgs boson is performed using proton-proton collision data collected with the CMS detector at the LHC in 2016 at a center-of-mass energy s=13TeV, corresponding to ...an integrated luminosity of 35.9fb−1. The search targets the production of a Higgs boson via vector boson fusion. The data are found to be in agreement with the background contributions from standard model processes. An observed (expected) upper limit of 0.33(0.25), at 95% confidence level, is placed on the branching fraction of the Higgs boson decay to invisible particles, assuming standard model production rates and a Higgs boson mass of 125.09 GeV. Results from a combination of this analysis and other direct searches for invisible decays of the Higgs boson, performed using data collected at s=7, 8, and 13 TeV, are presented. An observed (expected) upper limit of 0.19(0.15), at 95% confidence level, is set on the branching fraction of invisible decays of the Higgs boson. The combined limit represents the most stringent bound on the invisible branching fraction of the Higgs boson reported to date. This result is also interpreted in the context of Higgs-portal dark matter models, in which upper bounds are placed on the spin-independent dark-matter-nucleon scattering cross section.
Observation of t t ¯ H Production Erö, J.; Flechl, M.; Schieck, J. ...
Physical review letters,
06/2018, Letnik:
120, Številka:
23
Journal Article
Recenzirano
Odprti dostop
Here, the observation of Higgs boson production in association with a top quark-antiquark pair is reported, based on a combined analysis of proton-proton collision data at center-of-mass energies of ...√s=7, 8, and 13 TeV, corresponding to integrated luminosities of up to 5.1, 19.7, and 35.9 fb-1, respectively. The data were collected with the CMS detector at the CERN LHC. The results of statistically independent searches for Higgs bosons produced in conjunction with a top quark-antiquark pair and decaying to pairs of W bosons, Z bosons, photons, τ leptons, or bottom quark jets are combined to maximize sensitivity. An excess of events is observed, with a significance of 5.2 standard deviations, over the expectation from the background-only hypothesis. The corresponding expected significance from the standard model for a Higgs boson mass of 125.09 GeV is 4.2 standard deviations. The combined best fit signal strength normalized to the standard model prediction is1.26+0.31–0.26.
A search for narrow, low-mass, scalar, and pseudoscalar resonances decaying to bottom quark-antiquark pairs is presented. The search is based on events recorded in √ s = 13 TeV proton-proton ...collisions with the CMS detector at the LHC, collected in 2016, and corresponding to an integrated luminosity of 35.9 fb−1 . The search selects events in which the resonance would be produced with high transverse momentum because of the presence of initial- or final-state radiation. In such events, the decay products of the resonance would be reconstructed as a single large-radius jet with high mass and two-prong substructure. A potential signal would be identified as a narrow excess in the jet invariant mass spectrum. No evidence for such a resonance is observed within the mass range from 50 to 350 GeV, and upper limits at 95% confidence level are set on the product of the cross section and branching fraction to a bottom quark-antiquark pair. These constitute the first constraints from the LHC on exotic bottom quark-antiquark resonances with masses below 325 GeV.
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