Measurement of the radiation field surrounding the Collider Detector at Fermilab

We present here the first direct and detailed measurements of the spatial distribution of the ionizing radiation surrounding a hadron collider experiment. Using data from two different exposures we measure the effect of additional shielding on the radiation field around the Collider Detector at Fermilab (CDF). Employing a simple model we parameterize the ionizing radiation field surrounding the detector.Comment: PDF document, 5 pages, including 10 encapsulated postscript figures: Proceedings for the IEEE/NSS-MIC 2003 Conference, Portland, Oregon, October 19-25, 200

Timing performance of a Micro-Channel-Plate Photomultiplier Tube

The spatial dependence of the timing performance of the R3809U-50 Micro-Channel-Plate PMT (MCP-PMT) by Hamamatsu was studied in high energy muon beams. Particle position information is provided by a GEM tracker telescope, while timing is measured relative to a second MCP-PMT, identical in construction. In the inner part of the circular active area (radius r5.5 mm) the time resolution of the two MCP-PMTs combined is better than 10 ps. The signal amplitude decreases in the outer region due to less light reaching the photocathode, resulting in a worse time resolution. The observed radial dependence is in quantitative agreement with a dedicated simulation. With this characterization, the suitability of MCP-PMTs as t0 reference detectors has been validated.Peer reviewe

Measurements of the Vector boson production with the ATLAS Detector

The electroweak sector of the Standard Model can be tested by precision measurements of its fundamental parameters, such as the W boson mass or the electroweak mixing angle. In this talk, we present the first measurement of the W boson mass, based on the 7 TeV data set corresponding to an integrated luminosity of 4.6 fb$^{-1}$. With these samples the detector and physics modelling has been studied in great detail, leading to an overall uncertainty of 19 MeV. The ATLAS collaboration also performed a new precise triple differential cross-section measurement as a function of M(ll), dilepton rapidity and $cos\theta^{*}$ defined in the Collins-Soper frame. This measurement provides sensitivity to the PDFs and the Z forward-backward asymmetry, $A_{FB}$, which is derived and will be presented. The later builds the foundation for a possible future extraction of the weak-mixing angle. The production of jets in association with vector bosons is an important process to study perturbative QCD in a multi-scale environment. The ATLAS collaboration has performed new measurements of vector boson + jets cross sections, differential in several kinematic variables, in proton-proton collision data taken at center-of-mass energies of 8 TeV and 13 TeV, which will be presented. The measurements are compared to state-of-the art theory predictions. They are sensitive to higher-order pQCD effects, and can be used to constrain the proton structure. In addition, we present a new measurement of the splitting scales of the kt jet-clustering algorithm for final states containing a Z-boson candidate at a centre-of-mass energy of 8 TeV

TOP MASS MEASUREMENT AT CDF

(for the CDF Collaboration) We report on recent measurements of the top quark mass using t¯t candidate events selected in ≃ 320 pb −1 of data from the ”Run II ” operation period of the Tevatron p¯p collider. More emphasis is given on the best single measurement to date (Mtop = 173.5 +3.9 −3.8 GeV/c2), provided by CDF using the ”lepton plus jets ” channel, where one W decays to a lepton-neutrino pair and the other into quarks (top quarks decay to Wb almost 100 % of the time).

Comparison of CDF electron response between test beam and simulation

A comparison of the CDF (Collider Detector at Fermilab) central calorimeter electron response between 1991 test beam electron data and the CDF full detector simulation, using six variables that are used to identify electrons in CDF, is performed. Possible parameters that could be used to tune the simulation are also pointed out

Welfare analysis and bootstrapping

This paper examines the effects of the entry and the 1992 CAP reform on maize producers' welfare and on economic efficiency. This welfare analysis used a bootstrap resampling technique that provided standard errors and confidence intervals for the estimates. These empirical analysis has shown that the price-policy induced changes in farmers' economic welfare were significant at commonly used levels of statistical significance.

The ATLAS RPC-BIS78 Readout and Trigger System

In this paper we describe the BIS78-RPC detector, mainly focusing on the Readout and Trigger electronics system. The aim of the BIS78 project is to provide new integrated sMDT+RPC chambers for the Phase-I upgrade of the Muon Spectrometer of the ATLAS Experiment at the LHC at CERN. The BIS78-RPC chambers are also a pilot deployment of RPC chambers to be used in the full barrel inner layer for Phase-II upgrade. The on-chamber front-ends include an amplifier, a discriminator ASIC and an LVDS transmitter. This signal is digitized by CERN HPTDC chips and then processed by an FPGA which is the heart of the readout and trigger processing. The on-detector electronics and trigger system, and in particular the firmware, is described in this paper, including the related validation test results