Search results for "Monte carlo method"
showing 10 items of 1234 documents
Measurement of the transverse momentum distribution of Z/γ⁎ bosons in proton–proton collisions at s=7 TeV with the ATLAS detector
2011
A measurement of the Z/gamma* transverse momentum (p(T)(Z)) distribution in proton-proton collisions at root s = 7 TeV is presented using Z/gamma* -> e(+)e(-) and Z/gamma* -> mu(+)mu(-) decay ...
Electroweak Higgs Boson Plus Three Jet Production at Next-to-Leading-Order QCD
2013
We calculate next-to-leading order (NLO) QCD corrections to electroweak Higgs boson plus three jet production. Both vector boson fusion (VBF) and Higgs-strahlung type contributions are included along with all interferences. The calculation is implemented within the MATCHBOX NLO framework of the HERWIG++ event generator.
Accelerating Ab Initio Nucleon Structure Calculations with All-Mode-Averaging on Gordon
2014
The composition of nucleons has long been known to be sub-atomic particles called quarks and gluons, which interact through the strong force and theoretically can be described by Quantum Chromodynamics (QCD). Lattice QCD (LQCD), in which the continuous space-time is translated into grid points on a four-dimensional lattice and ab initio Monte Carlo simulations are performed, is by far the only model-independent method to study QCD with controllable errors. We report the successful application of a novel algorithm, All-Mode-Averaging, in the LQCD calculations of nucleon internal structure on the Gordon supercomputer our award of roughly 6 million service units through XSEDE. The application …
HAWK 2.0: A Monte Carlo program for Higgs production in vector-boson fusion and Higgs strahlung at hadron colliders
2014
The Monte Carlo integrator HAWK provides precision predictions for Higgs production at hadron colliders in vector-boson fusion and Higgs strahlung, i.e. in production processes where the Higgs boson is Attached to WeaK bosons. The fully differential predictions include the full QCD and electroweak next-to-leading-order corrections. Results are computed as integrated cross sections and as binned distributions for important hadron-collider observables.
Line shifts and broadenings in polarizable liquids
1989
We present a new dynamical derivation of the approximation used by Thompson, Schweizer, and Chandler and by Ho/ye and Stell for the frequency dependent polarizability of a quantum fluid with harmonically bound dipole moments; the Drude model. The derivation is the same for classical and quantum liquids—as is of course the result which agrees with that of these authors. We then refine the theory by taking account of the limited number of energy levels available, i.e., we replace the harmonic approximation by a two level approximation, for the target atom. This leads to a prefactor ω0I/ω0 in the line shift of an impurity atom in a fluid computed by Chandler, Schweitzer, and Wolynes: ω0 and ω0…
Density functional study of two-dimensionalHe4clusters
2005
Binding energies and density profiles of two-dimensional systems of liquid He-4 with different geometries are studied by means of a zero-range density functional adjusted to reproduce the line tension obtained in a previous diffusion Monte Carlo calculation (lambda_{DMC}=0.121 K/A). It is shown that this density functional provides accurate results for the binding energy of large clusters with a reasonable computational effort.
Phase transitions and quantum effects in adsorbed monolayers
1996
Phase transitions in absorbed (two-dimensional) fluids and in absorbed layers of linear molecules are studied with a combination of path integral Monte Carlo (PIMC), Gibbs ensemble Monte Carlo (GEMC), and finite size scaling techniques. For a classical (nonadditive) hard-disk fluid the “critical” nonadditivities, where the entropy-driven phase separations set in, are presented. For a fluid with internal quantum states the gas-liquid coexistence region, tricritical, and triple points can be determined, and a comparison with density functional (DFT) results shows good agreement for the freezing densities. LinearN 2 molecules adsorbed on graphite (in the √3 × √3 structure) show a transition fr…
Highlights of top quark cross-section measurements at ATLAS
2017
The highlights of the measurements of top quark production in proton-proton collisions at the Large Hadron Collider with the ATLAS detector are presented. The inclusive measurements of the top-pair production cross section have reached high precision and are compared to the best available theoretical calculations. The differential cross section measurements, including results using boosted top quarks, probe our understanding of top-pair production in the TeV regime. The results are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers. Measurements of the single top quark production cross section are presented in the t -channel and s -channel…
A combined molecular dynamics and Monte Carlo study of the approach towards phase separation in colloid-polymer mixtures.
2011
A coarse-grained model for colloid-polymer mixtures is investigated where both colloids and polymer coils are represented as point-like particles interacting with spherically symmetric effective potentials. Colloid-colloid and colloid-polymer interactions are described by Weeks-Chandler-Andersen potentials, while the polymer-polymer interaction is very soft, of strength k(B)T/2 for maximum polymer-polymer overlap. This model can be efficiently simulated both by Monte Carlo and molecular dynamics methods, and its phase diagram closely resembles that of the well-known Asakura-Oosawa model. The static and dynamic properties of the model are presented for systems at critical colloid density, va…
Estimating Terrestrial Neutron-Induced SEB Cross-Sections and FIT Rates for High-Voltage SiC Power MOSFETs
2019
Cross sections and failure in time rates for neutron-induced single-event burnout (SEB) are estimated for SiC power MOSFETs using a method based on combining results from heavy ion SEB experimental data, 3-D TCAD prediction of sensitive volumes, and Monte Carlo radiation transport simulations of secondary particle production. The results agree well with experimental data and are useful in understanding the mechanisms for neutron-induced SEB data.