Light hadron masses with an O(a2)O(a^2) improved NNN action

Meson and baryon masses in the light (u,d and s) sector are calculated using tadpole-improved gauge field and fermion actions. These are corrected to order $O(a^2)$ on the classical level using next-nearest-neighbour terms. The results, obtained at lattice spacings of 0.4 and 0.27fm, are compared to Wilson action calculations.Comment: Talk presented at LATTICE96(improvement

Heavy-light meson spectrum with and without NRQCD

Results for the spectrum of S and P-wave charmed mesons are obtained in the quenched approximation from a tadpole-improved anisotropic gauge field action and a D234 quark action. This is compared to the spectrum obtained from an NRQCD charm quark and a D234 light antiquark. NRQCD results for bottom mesons are also discussed.Comment: 4 pages, 5 figures. Lattice 2000 (Heavy Quark Physics

P-wave heavy-light mesons using NRQCD and D234

The masses of S- and P-wave heavy-light mesons are computed in quenched QCD using a classically and tadpole-improved action on anisotropic lattices. Of particular interest are the splittings among P-wave states, which have not yet been resolved experimentally; even the ordering of these states continues to be discussed in the literature. The present work leads to upper bounds for these splittings, and is suggestive, but not conclusive, about the ordering.Comment: LATTICE99(heavy quarks) - 3 pages including 3 figure

The charmed and bottom meson spectrum from lattice NRQCD

The mass spectrum of S and P-wave mesons containing a single heavy quark has been computed using quenched lattice nonrelativistic QCD. Numerical results have been obtained at first, second and third order in the heavy quark expansion, so convergence can be discussed. The computed spectrum of charmed and bottom mesons is compared to existing model calculations and experimental data.Comment: 4 pages, 3 figures. To be published in the proceedings of the 4th International Conference on Hyperons, Charm and Beauty Hadrons, Valencia, Spain, 27-30 Jun 200

Normal mode analysis for scalar fields in BTZ black hole background

We analyze the possibility of inequivalent boundary conditions for a scalar field propagating in the BTZ black hole space-time. We find that for certain ranges of the black hole parameters, the Klein-Gordon operator admits a one-parameter family of self-adjoint extensions. For this range, the BTZ space-time is not quantum mechanically complete. We suggest a physically motivated method for determining the spectra of the Klein-Gordon operator.Comment: 6 pages, no figure, late

Stochastic Production Of Kink-Antikink Pairs In The Presence Of An Oscillating Background

We numerically investigate the production of kink-antikink pairs in a $(1+1)$ dimensional $\phi^4$ field theory subject to white noise and periodic driving. The twin effects of noise and periodic driving acting in conjunction lead to considerable enhancement in the kink density compared to the thermal equilibrium value, for low dissipation coefficients and for a specific range of frequencies of the oscillating background. The dependence of the kink-density on the temperature of the heat bath, the amplitude of the oscillating background and value of the dissipation coefficient is also investigated. An interesting feature of our result is that kink-antikink production occurs even though the system always remains in the broken symmetry phase.Comment: Revtex, 21 pages including 7 figures; more references adde

Additive and Multiplicative Noise Driven Systems in 1+1 Dimensions: Waiting Time Extraction of Nucleation Rates

We study the rate of true vacuum bubble nucleation numerically for a phi^4 field system coupled to a source of thermal noise. We compare in detail the cases of additive and multiplicative noise. We pay special attention to the choice of initial field configuration, showing the advantages of a version of the quenching technique. We advocate a new method of extracting the nucleation time scale that employs the full distribution of nucleation times. Large data samples are needed to study the initial state configuration choice and to extract nucleation times to good precision. The 1+1 dimensional models afford large statistics samples in reasonable running times. We find that for both additive and multiplicative models, nucleation time distributions are well fit by a waiting time, or gamma, distribution for all parameters studied. The nucleation rates are a factor three or more slower for the multiplicative compared to the additive models with the same dimensionless parameter choices. Both cases lead to high confidence level linear fits of ln(nucleation time) vs. 1/T plots, in agreement with semiclassical nucleation rate predictions.Comment: 38 pages, 20 figures, 6 table

Microscopic simulation of xenon-based optical TPCs in the presence of molecular additives

[EN] We introduce a simulation framework for the transport of high and low energy electrons in xenon-based optical time projection chambers (OTPCs). The simulation relies on elementary cross sections (electron-atom and electron-molecule) and incorporates, in order to compute the gas scintillation, the reaction/quenching rates (atom-atom and atom-molecule) of the first 41 excited states of xenon and the relevant associated excimers, together with their radiative cascade. The results compare positively with observations made in pure xenon and its mixtures with CO2 and CF4 in a range of pressures from 0.1 to 10 bar. This work sheds some light on the elementary processes responsible for the primary and secondary xenon-scintillation mechanisms in the presence of additives, that are of interest to the OTPC technology.DGD is supported by the Ramon y Cajal program (Spain) under contract number RYC-2015-18820. The authors want to acknowledge the RD51 collaboration for encouragement and support during the elaboration of this work, and in particular discussions with F. Resnati, A. Milov, V. Peskov, M. Suzuki and A. F. Borghesani. The NEXT Collaboration acknowledges support from the following agencies and institutions: the European Research Council (ERC) under the Advanced Grant 339787-NEXT; the Ministerio de Economia y Competitividad of Spain under grants FIS2014-53371-C04 and the Severo Ochoa Program SEV-2014-0398; the GVA of Spain under grant PROM-ETEO/2016/120; the Portuguese FCT and FEDER through the program COMPETE, project PTDC/FIS-NUC/2525/2014 and UID/FIS/04559/2013; the U.S. Department of Energy under contracts number DE-AC02-07CH11359 (Fermi National Accelerator Laboratory) and DE-FG02-13ER42020 (Texas A& and the University of Texas at Arlington.Azevedo, C.; Gonzalez-Diaz, D.; Biagi, SF.; Oliveira, CAB.; Henriques, CAO.; Escada, J.; Monrabal, F.... (2018). Microscopic simulation of xenon-based optical TPCs in the presence of molecular additives. Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment. 877:157-172. https://doi.org/10.1016/j.nima.2017.08.049S15717287

Customer emotions in service failure and recovery encounters

Emotions play a significant role in the workplace, and considerable attention has been given to the study of employee emotions. Customers also play a central function in organizations, but much less is known about customer emotions. This chapter reviews the growing literature on customer emotions in employee–customer interfaces with a focus on service failure and recovery encounters, where emotions are heightened. It highlights emerging themes and key findings, addresses the measurement, modeling, and management of customer emotions, and identifies future research streams. Attention is given to emotional contagion, relationships between affective and cognitive processes, customer anger, customer rage, and individual differences