Search results for "Correlation"

Bottomonium precision tests from full lattice QCD: Hyperfine splitting, ϒ leptonic width, and b quark contribution to e+e−→hadrons

2021

We calculate the mass difference between the $\mathrm{\ensuremath{\Upsilon}}$ and ${\ensuremath{\eta}}_{b}$ and the $\mathrm{\ensuremath{\Upsilon}}$ leptonic width from lattice QCD using the highly improved staggered quark formalism for the $b$ quark and including $u$, $d$, $s$ and $c$ quarks in the sea. We have results for lattices with lattice spacing as low as 0.03 fm and multiple heavy quark masses, enabling us to map out the heavy quark mass dependence and determine values at the $b$ quark mass. Our results are ${M}_{\mathrm{\ensuremath{\Upsilon}}}\ensuremath{-}{M}_{{\ensuremath{\eta}}_{b}}=57.5(2.3)(1.0)\text{ }\text{ }\mathrm{MeV}$ (where the second uncertainty comes from neglect of …

Quantum identical particle indistinguishability: concepts and applications

2020

Incommensurate phases of a bosonic two-leg ladder under a flux

2016

A boson two--leg ladder in the presence of a synthetic magnetic flux is investigated by means of bosonization techniques and Density Matrix Renormalization Group (DMRG). We follow the quantum phase transition from the commensurate Meissner to the incommensurate vortex phase with increasing flux at different fillings. When the applied flux is $\rho \pi$ and close to it, where $\rho$ is the filling per rung, we find a second incommensuration in the vortex state that affects physical observables such as the momentum distribution, the rung-rung correlation function and the spin-spin and charge-charge static structure factors.

A measurement of αs from the scaling violation in e+e- annihilation

1997

The hadronic fragmentation functions of the various quark flavours and of gluons are measured in a study of the inclusive hadron production from $\zz$ decays with the DELPHI detector and are compared with the fragmentation functions measured elsewhere at energies between 14 GeV and 91 GeV. A large scaling violation is observed, which is used to extract the strong coupling constant from a fit using a numerical integration of the second order DGLAP evolution equations. The result is \begin{displaymath} \alpha_s(M_Z) = 0.124^{+0.006}_{-0.007}(exp)\pm 0.009 (theory) \end{displaymath} where the first error represents the experimental uncertainty and the second error is due to the factorization a…

Theoretical study of YbOH173 to search for the nuclear magnetic quadrupole moment

2019

A $CP$-violating interaction of the nuclear magnetic quadrupole moment (MQM) with electrons in the ytterbium monohydroxide molecule $^{173}\mathrm{YbOH}$ is considered. Both the MQM of the $^{173}\mathrm{Yb}$ nucleus and the molecular interaction constant ${W}_{M}$ are estimated. Electron correlation effects are taken into account within the relativistic Fock-space coupled-cluster method. Results are interpreted in terms of the strength constants of $CP$-violating nuclear forces, neutron dipole moment (EDM), QCD vacuum angle $\ensuremath{\theta}$, quark EDMs, and chromo-EDMs.

From RHIC to LHC

2007

Measurements of the nuclear modification factor of inclusive yields of $\pi^0$, $p\bar{p}$, non-phtonic electrons and prompt photon measured at RHIC are reviewed. Some of the difficulties arising from interpretation of these measurements such as similarity of the suppression pattern of light and heavy quarks, quarks and gluons, light quarks and prompt photon are discussed. The potential of two-particle and promt photon correlation technique to unravel some of these open questions is presented. An emphasis is given to the influence of partonic transverse momentum on the prompt-photon correlations. The smearing between the trigger photon and back-to-back jet at LHC energy is discussed.

CLS 2+1 flavor simulations at physical light-and strange-quark masses

2017

We report recent efforts by CLS to generate an ensemble with physical light- and strange-quark masses in a lattice volume of 192x96^3 at $\beta=3.55$ corresponding to a lattice spacing of 0.064 fm. This ensemble is being generated as part of the CLS 2+1 flavor effort with improved Wilson fermions. Our simulations currently cover 5 lattice spacings ranging from 0.039 fm to 0.086 fm at various pion masses along chiral trajectories with either the sum of the quark masses kept fixed, or with the strange-quark mass at the physical value. The current status of simulations is briefly reviewed, including a short discussion of measured autocorrelation times and of the main features of the simulation…

Three-particle correlations in QCD jets and beyond

2011

In this paper, we present a more detailed version of our previous work for three-particle correlations in quark and gluon jets [1]. We give theoretical results for this observable in the double logarithmic approximation and the modified leading logarithmic approximation. In both resummation schemes, we use the formalism of the generating functional and solve the evolution equations analytically from the steepest descent evaluation of the one-particle distribution. In addition, in this paper we include predictions beyond the limiting spectrum approximation and study this observable near the hump of the single inclusive distribution. We thus provide a further test of the local parton hadron d…

Quantum control and long-range quantum correlations in dynamical Casimir arrays

2015

The recent observation of the dynamical Casimir effect in a modulated superconducting waveguide, coronating thirty years of world-wide research, empowered the quantum technology community with a powerful tool to create entangled photons on-chip. In this work we show how, going beyond the single waveguide paradigm using a scalable array, it is possible to create multipartite nonclassical states, with the possibility to control the long-range quantum correlations of the emitted photons. In particular, our finite-temperature theory shows how maximally entangled $NOON$ states can be engineered in a realistic setup. The results here presented open the way to new kinds of quantum fluids of light,…

Adequate number of consumers in a liking test. Insights from resampling in seven studies

2014

The recommended number of consumers to be enrolled in a hedonic test comparing several products usually ranges from 50 to 100, at least if no liking segmentation is sought. This paper seeks to examine whether such a panel size range is adequate, by means of 7 trials with different levels of product space complexity. Five types of products were tested: Two varied in fattiness and sweetness and were tested under the same conditions in two separate laboratories (4 trials); the remaining three, varying in taste and texture, were each tested in a different laboratory (3 trials). Each of the 7 trials was run by a different laboratory. Each of the seven laboratories enrolled in its trial 150 consu…