49282181
The acceptance probability in the hybrid Monte Carlo method
Abstract We study the acceptance probability in the hybrid Monte Carlo method applied to lattice QCD with dynamical fermions We investigate in detail its dependence upon the step-size and the parameters β, m q and V , and suggest a simple phenomenological formula for this dependence.
122166973
The phase diagram of QCD: methods and logic of the comparison of experiments and theory
Abstract A small review of the phase diagram of QCD is presented. This is followed by a discussion of the conditions under which experimental data on the fluctuations of conserved quantities in heavy-ion collisions can be treated in the grand canonical ensemble. A robust method for detecting the presence of a nearby critical point in experiments is given. There is a short discussion of the need for non-Gaussian error analysis.
121387686
Hybrid Monte Carlo simulations of a two-dimensional gauge theory
Through a study of the dynamics of the two-dimensional U(1) pure gauge theory we find exponential slowing down in barrier penetration problems. We verify that the dynamical critical exponent in HMC can be tuned exactly to 1, and that normal and gauge fixed updates have equal cost.
17443615
Lattice QCD for RHIC
I briefly introduce the methods by which lattice QCD predictions for RHIC are obtained. Next I deal with lattice determinations of strangeness production and event-to-event fluctuations of conserved quantities. I also present a new diagrammatic method for computing derivatives with respect to chemical potentials, and conclude with discussions of some tests of thermal perturbation theory which follow.
119431013
A precise determination of T_c in QCD from scaling
Existing lattice data on the QCD phase transition are analyzed in renormalized perturbation theory. In quenched QCD it is found that T_c scales for lattices with only 3 time slices, and that T_c/Lambda_msbar=1.15 \pm 0.05. A preliminary estimate in QCD with two flavours of dynamical quarks shows that this ratio depends on the quark mass. For realistic quark masses we estimate T_c/Lambda_msbar=0.49 \pm 0.02. We also investigate the equation of state in quenched QCD at 1-loop order in renormalised perturbation theory.
123004962
Flavour degrees of freedom and the transition temperature in QCD
We study the finite temperature transition in QCD with four flavours of dynamical quarks. Our simulation is performed on an 8×16 3 lattice for quarks of mass ma=0.01. At the coupling β c =5.15, we find long-lived metastable states, as well as an abrupt change in the entropy density, suggesting a first order phase transition. Using presently available results from corresponding calculations of the hadron masses and the chiral condensate, this gives us a transition temperature T c ≅100 MeV, which is a factor two lower than the transition temperature found in quenched QCD.
121879312
Isobaric analog impurity from total and differential neutron scattering cross sections of silicon
Resonance parameters for sour resonances in Si have been obtained by analyzing measured differential neutron scattering cross sections combined with the total neutron cross section in the neutron energy range 1.05--1.40 MeV and applying R-matrix single channel multilevel theory. The resonance at 1254 krB has been identified as the s-wave analog resonance in /sup 29/Si. The identification also takes into account experimental radiative neutron capture data and shell model calculations for the radiative width. Estimates of the isospin mixing matrix elements are given.
121535698
Intermittency analysis of fragmenting nuclei with exact conservation laws
We show that the speculative charge bin size dependence of the scaled factorial moments for fragmenting nuclei in recent nuclear emulsion data may be attributed in part to simple conservation laws. Monte Carlo results from both the Thermodynamic Model and an Evaporation Model suggest that in such studies most or all of the effect is due to the fact that there exist constraints owing to conserved quantities.
118602353
Zero textures of the neutrino mass matrix from cyclic family symmetry
Abstract We present the symmetry realization of the phenomenologically viable Frampton–Glashow–Marfatia (FGM) two zero texture neutrino mass matrices in the flavor basis within the framework of the type ( I + II ) seesaw mechanism natural to SO(10) grand unification. A small Abelian cyclic symmetry group Z 3 is used to realize these textures except for class C for which the symmetry is enlarged to Z 4 . The scalar sector is restricted to the Standard Model (SM) Higgs doublet to suppress the flavor changing neutral currents. Other scalar fields used for symmetry realization are at the most two scalar triplets and, in some cases, a complex scalar singlet. Symmetry realization of one zero textures has, also, been presented.
120228440
Regularization of fermion loops in gauge models
Fermion loops in gauge models with ${\ensuremath{\gamma}}_{5}$ couplings cannot be regularized in a gauge-invariant manner either by the method of auxiliary fields or by dimensional continuation. It is shown that in the absence of a gauge-invariant regularization procedure, the method of auxiliary fields can be employed in such a way that non-gauge-invariance is confined to the renormalization constants. It is thus possible to obtain gauge-invariant renormalized results as well as resolve anomalies without the use of Ward's identities. Explicit calculations are carried out for the self-energy and triangle diagrams with fermion loops in the Appelquist-Quinn model. The present treatment is also compared with naive dimensional regularization for the ${\ensuremath{\gamma}}_{5}$ couplings.
10127072
Phenomenological Analysis of Hybrid Textures of Neutrinos
Abstract We present a comprehensive phenomenological analysis of the allowed hybrid textures of neutrinos. Out of a total of sixty hybrid textures with one equality between the elements of neutrino mass matrix and one texture zero only twenty three are found to be viable at 99% C.L. whereas the earlier analysis found fifty four to be viable. We examine the phenomenological implications of the allowed hybrid textures including Majorana type CP-violating phases, 1–3 mixing angle and Dirac type CP-violating phase, δ. We, also, obtain lower bound on effective Majorana mass for all the allowed hybrid textures.