1,608 research outputs found

    The CMS Silicon Strip Tracker

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    The CMS strip tracker is the first large scale tracker entirely based on silicon detectors technology. It consists of 198 m^2 of detector sensitive area instrumenting the inner region of the experiment with a pseudo-rapidity coverage of eta <2.5. This instrument, together with a silicon pixel system, is expected to perform robust tracking and detailed vertex reconstruction while embedded in the LHC high radiation and high luminosity environment. The project is in a well advanced construction phase: the detector module production is completed, the integration of the single components into large sub-detector units is underway and the full tracker commissioning is about to start. In this paper, after a description of the tracker layout, a detector modules production overview and a summary of the integration procedures for the inner barrel part of the tracker will be reported

    tracking for proton computed tomography

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    In hadron therapy a highly conformed irradiation field is delivered to the target by precisely moving the particle beam and, at the same time, modulating its energy with the aim to cover the tumor volume with the requested dose sparing the surrounding healthy tissues as much as possible. To setup a robust treatment plan the Stopping Power (SP) map for each patient should be measured and the volume to be irradiated precisely located. To improve the precision of the SP map determination the use of a proton beam to perform a 'proton Computed Tomography' (pCT) could be the ideal solution. To be effective in reducing the uncertainties in dose spatial distribution, this novel method should keep the SP map spatial resolution below one millimeter. Tracking in presence of large multiple scattering will be discussed in these proceedings together with the concept of 'most likely path' (MLP). A generalization of the studies on this issue will be introduced with the aim to describe instrumental effects on the MLP spatial resolution. The pCT apparatus, based on a Silicon microstrip tracker followed by a calorimeter to measure single protons trajectory and their residual energy, will be reviewed with particular emphasis on the R&D ongoing on this subject and the results already obtained. New prototypes presently under construction, which will be suitable for pre-clinical studies, will be described too

    PRIMA+: A proton Computed Tomography apparatus

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    The proton Computed Tomography (pCT) is a medical imaging method, based on the use of proton beams with kinetic energy of the order of 250 MeV, aimed to directly measure the stopping power distribution of tissues thus improving the present accuracy of treatment planning in hadron therapy. A pCT system should be capable to measure tissue electron density with an accuracy better than 1% and a spatial resolution better than 1 mm. The blurring effect due to multiple Coulomb scattering can be mitigated by single proton tracking technique. As a first step towards pCT the PRIMA+ Collaboration built a prototype capable to carry out a single radiography and a tomographic image of a rotating object. This apparatus includes a silicon microstrip tracker to identify the proton trajectory and a YAG:Ce calorimeter to measure the particle residual energy

    La Fanciulla del West

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    Direcció: Mario ParentiEmpresa: Juan A. PamiasDe cada obra s'ha digitalitzat un programa sencer. De la resta s'han digitalitzat les parts que són diferents

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

    Search for stop and higgsino production using diphoton Higgs boson decays

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    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass
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