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.
Grid computing at the DØ experiment Kurca, T.
2007 IEEE Nuclear Science Symposium Conference Record,
2007-Oct., Letnik:
2
Conference Proceeding
D0 is a pioneer in grid computing for large scale production activities involving the handling of collider data samples. A data grid (SAM) has been used since the start of Tevatron Run II as the sole ...means of data transport (enabling local offsite analysis). The focus of the computational grid (SAM-grid) so far has been on production activities. Integration of SAM-Grid with other grids, like LCG and OSG are ongoing projects. All Monte Carlo data are produced off-site. In 2005 and 2007 large fractions of the Run IIa and Run IIb data sets respectively (1 billion events) were reprocessed using native SAM-Grid, LCG and OSG resources. The value of grid computing to the D0 experiment is conservatively estimated at roughly 4M/year. Evolution towards full grid computing and lessons learned from these activities will be discussed.
We describe an analysis comparing the p (p) over bar elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM ...Collaboration at 2.76, 7, 8, and 13 TeVusing a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of root s = 1.96 TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4s level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering for which the significance is between 3.4s and 4.6s. The combined significance is larger than 5 sigma and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound.
The H1 backward calorimeter BEMC and its inclusive electron trigger Bán, J.; Bauhoff, W.; Bruncko, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/1996, Letnik:
372, Številka:
3
Journal Article
Recenzirano
Odprti dostop
A sandwich type lead-scintillator electromagnetic calorimeter with wavelength shifter optical readout has been successfully operated at the DESY ep collider HERA in the H1 detector for three years. ...The mechanical design of the calorimeter together with the associated electronics and the inclusive electron trigger as well as its performance and stability in test beams and at the ep collider HERA are described in detail.
We present the observation of doubly produced J/psi mesons with the D0 detector at Fermilab in p (p) over bar collisions at root s = 1.96 TeV. The production cross section for both singly and doubly ...produced J/psi mesons is measured using a sample with an integrated luminosity of 8.1 fb(-1). For the first time, the double J/psi production cross section is separated into contributions due to single and double parton scatterings. Using these measurements, we determine the effective cross section seff, a parameter characterizing an effective spatial area of the parton-parton interactions and related to the parton spatial density inside the nucleon.
High energy physics experiments periodically reprocess data, in order to take advantage of improved understanding of the detector and the data processing code. Between February and May 2007, the ...DZero experiment has reprocessed a substantial fraction of its dataset. This consists of half a billion events, corresponding to about 100 TB of data, organized in 300,000 files. The activity utilized resources from sites around the world, including a dozen sites participating to the Open Science Grid consortium (OSG). About 1,500 jobs were run every day across the OSG, consuming and producing hundreds of Gigabytes of data. Access to OSG computing and storage resources was coordinated by the SAM-Grid system. This system organized job access to a complex topology of data queues and job scheduling to clusters, using a SAM-Grid to OSG job forwarding infrastructure. For the first time in the lifetime of the experiment, a data intensive production activity was managed on a general purpose grid, such as OSG. This paper describes the implications of using OSG, where all resources are granted following an opportunistic model, the challenges of operating a data intensive activity over such large computing infrastructure, and the lessons learned throughout the project.
We present a measurement of forward-backward asymmetry in top quark-antiquark production in proton-antiproton collisions in the final state containing a lepton and at least four jets. Using a dataset ...corresponding to an integrated luminosity of 5.4 fb-1, collected by the D0 experiment at the Fermilab Tevatron Collider, we measure the t{bar t} forward-backward asymmetry to be (9.2 ± 3.7)% at the reconstruction level. When corrected for detector acceptance and resolution, the asymmetry is found to be (19.6 ± 6.5)%. We also measure a corrected asymmetry based on the lepton from a top quark decay, found to be (15.2 ± 4.0)%. The results are compared to predictions based on the next-to-leading-order QCD generator mc@nlo. The sensitivity of the measured and predicted asymmetries to the modeling of gluon radiation is discussed.
We present evidence for the exotic charged charmoniumlike state Z(c)(+/-)(3900) decaying to J/psi pi(+/-) in semi-inclusive weak decays of b-flavored hadrons. The signal is correlated with a parent ...J/psi pi(+)pi(-) system in the invariant-mass range 4.2-4.7 GeV that would include the exotic structure Y(4260). The study is based on 10.4 fb(-1) of p (p) over bar collision data collected by the D0 experiment at the Fermilab Tevatron collider.
We present a study of the X-+/-(5568) using semileptonic decays of the B-s(0) meson using the full run II integrated luminosity of 10.4 fb(-1) in proton-antiproton collisions at a center of mass ...energy of 1.96 TeV collected with the DO detector at the Fermilab Tevatron Collider. We report evidence for a narrow structure, X-+/-(5568), in the decay sequence X-+/-(5568) -> B-s(0) pi(+/-) where B-s(0)-> mu(-/+) (DsX)-X-+/-, D-s(+/-)-> phi pi(+/-)which is consistent with the previous measurement by the DO Collaboration in the hadronic decay mode, X-+/-(5568) -> B-s(0)pi(+/-) where B-s(0 )-> J/psi phi. The mass and width of this state are measured using a combined fit of the hadronic and semileptonic data, yielding m = 5566.9(-3.1)(+3.2)(stat)(-1.2)(+0.6)(syst) MeV/c(2), Gamma = 18.6(-6.1)(+7.9)(stat)(-3.8)(+3.5) (syst) McV/c(2) with a significance of 6.7 sigma.
Measurement of the W boson mass with the D0 detector Acharya, B. S.; Augsten, K.; Bagby, L. ...
Physical review. D, Particles, fields, gravitation, and cosmology,
2014, Letnik:
89, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We give a detailed description of the measurement of the W boson mass, MW, performed on an integrated luminosity of 4.3 fb super(-1), which is based on similar techniques as used for our previous ...measurement done on an independent data set of 1 fb super(-1) of data. The data were collected using the DO detector at the Fermilab Tevatron Collider. This data set yields 1.68 x 10 super(6) W arrow right ev candidate events. We measure the mass using the transverse mass, electron transverse momentum, and missing transverse energy distributions. The MW measurements using the transverse mass and the electron transverse momentum distributions are the most precise of these three and are combined to give MW = 80.367 + or - 0.013(stat) + or - 0.022(syst) GeV = 80. 367 + or - 0.026 GeV. When combined with our earlier measurement on 1 fb super(-1) of data, we obtain MW = 80.375 + or - 0.023 GeV.
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