Search results for "Large"
showing 10 items of 2197 documents
ISOLTRAP Mass Measurements for Weak-Interaction Studies
2005
International audience; The conserved-vector-current (CVC) hypothesis of the weak interaction and the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix are two fundamental postulates of the Standard Model. While existing data on CVC supports vector current conservation, the unitarity test of the CKM matrix currently fails by more than two standard deviations. High-precision mass measurements performed with the ISOLTRAP experiment at ISOLDE/CERN provide crucial input for these fundamental studies by greatly improving our knowledge of the decay energy of super-allowed beta decays. Recent results of mass measurements on the beta emitters 18Ne, 22Mg, 34Ar, and 74Rb as pertaining to weak-i…
Direct search for light gluinos
1999
We present the results for a direct search for light gluinos through the appearance of $\eta\rightarrow 3\pi^{0}$ with high transverse momentum in the vacuum tank of the NA48 experiment at CERN. We find one event within a lifetime range of $10^{-9}-10^{-3}$s and another one between $10^{-10}-10^{-9}$s. Both events are consistent with the expected background from neutrons in the beam, produced by 450 GeV protons impinging on the Be targets, which interact with the residual air in the tank. From these data we give limits on the production of the hypothetical $g\widetilde{g}$ bound state, the $R^0$ hadron, and its $R^0\rightarrow\eta\widetilde{\gamma}$ decay in the $R^0$ mass range between 1 a…
Measurement of the quadratic slope parameter in the K-L -> 3 pi(0) decay Dalitz plot
2001
A value of (-6.1 +- 0.9_{stat} +- 0.5_{syst})*10^{-3} is obtained for the quadratic slope parameter h in the K_L -> 3\pi^0 decay Dalitz plot at the NA48 experiment at the CERN SPS. The result is based on 14.7*10^6 fully reconstructed K_L -> 3\pi^0 -> 6\gamma decays. This is the most precise measurement of any of the Dalitz plot slope parameters in the charged and neutral kaon decays so far.
Filaments in observed and mock galaxy catalogues
2010
Context. The main feature of the spatial large-scale galaxy distribution is an intricate network of galaxy filaments. Although many attempts have been made to quantify this network, there is no unique and satisfactory recipe for that yet. Aims. The present paper compares the filaments in the real data and in the numerical models, to see if our best models reproduce statistically the filamentary network of galaxies. Methods. We apply an object point process with interactions (the Bisous process) to trace and describe the filamentary network both in the observed samples (the 2dFGRS catalogue) and in the numerical models that have been prepared to mimic the data.We compare the networks. Result…
Thermalization in the initial stage of heavy ion collisions
2017
The high density non-abelian matter produced in heavy ion collisions is extremely anisotropic. Prethermal dynamics for the anisotropic and weakly coupled matter is discussed. Thermalization is realized with the effective kinetic theory in the leading order accuracy of the weakly coupled expansion. With the initial condition from color glass condensate, hydrodynamization time for the LHC energies is realized to be about 1 fm/c, while the thermalization happens much later than the hydrodynamization. peerReviewed
A Model for Homogenization of Solid Alloying Admixtures in an Induction Crucible Furnace
2014
The paper presents a methodology for identification of homogenization time of alloying inclusions in an induction crucible furnace. The methodology is based on the Large Eddy Simulation (LES) Euler-Lagrange calculation of inclusions and a regression model for size of the inclusions and their density. The presented regression model avoids the repeated LES calculations and, therefore, is suitable for an optimization task.
Numerical simulation and analysis of heat and mass transfer processes in metallurgical induction applications
2009
Comprehensive knowledge of the heat and mass transfer processes in the melt of induction applications is required to realize efficient metallurgical processes. Experimental and numerical studies of the melt flow in induction furnaces show that the flow pattern, which comprise several vortexes of the mean flow, and the temperature distribution in the melt are significantly influenced by low-frequency large scale flow oscillations. Two- and three-dimensional hydrodynamic calculations of the melt flow, using two-equation turbulence models based on Reynolds Averaged Navier-Stokes approach, do not predict the large scale periodic flow instabilities obtained from the experimental data. That's why…
Field and numerical study of river confluence flow structures
2010
River hydrodynamics Turbulent open channel flow and transport phenomena
Search for third generation scalar leptoquarks in pp collisions at √s = 7 TeV with the ATLAS detector
2013
A search for pair-produced third generation scalar leptoquarks is presented, using proton-proton collisions at √s = 7 TeV at the LHC. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 4.7 fb[superscript −1]. Each leptoquark is assumed to decay to a tau lepton and a b-quark with a branching fraction equal to 100%. No statistically significant excess above the Standard Model expectation is observed. Third generation leptoquarks are therefore excluded at 95% confidence level for masses less than 534 GeV.
Characterisation and mitigation of beam-induced backgrounds observed in the ATLAS detector during the 2011 proton-proton run
2013
This paper presents a summary of beam-induced backgrounds observed in the ATLAS detector and discusses methods to tag and remove background contaminated events in data. Triggerrate based monitoring of beam-related backgrounds is presented. The correlations of backgrounds with machine conditions, such as residual pressure in the beam-pipe, are discussed. Results from dedicated beam-background simulations are shown, and their qualitative agreement with data is evaluated. Data taken during the passage of unpaired, i.e. non-colliding, proton bunches is used to obtain background-enriched data samples. These are used to identify characteristic features of beam-induced backgrounds, which then are …