119094676
Scalar and tensor slueballs on asymmetric coarse lattices
Abstract Scalar and tensor glueball spectrum is studied using an improved gluonic action on asymmetric lattices in the pure SU (3) gauge theory. The smallest spatial lattice spacing is about 0.08 fm which makes the extrapolation to the continuum limit more reliable. In particular, attention is paid to the scalar glueball mass which is known to have problems in the extrapolation. Converting our lattice results to physical units using the scale set by the static quark potential, we obtain the following results for the glueball masses: M G (0 ++ ) = 1730(90) MeV for the scalar glueball mass and M G (2 ++ ) = 2400(95) MeV for the tensor glueball.
6175444
TUNING THE TADPOLE IMPROVED CLOVER WILSON ACTION ON COARSE ANISOTROPIC LATTICES
Wilson quark action, with tadpole improved clover term added, is studied on coarse anisotropic lattices. The bare velocity of light parameter in this action is determined nonperturbatively using the pseudo-scalar and vector meson dispersion relations for various values of the gauge coupling β and bare quark mass parameter κ.
15925356
A heavy Higgs particle in the TeV mass range
Abstract The first simulation results are presented on Higgs mass calculations in the spontaneously broken phase of the Higgs sector in the minimal Standard Model with higher derivative regulator. A heavy Higgs particle is found in the TeV mass range in the presence of a complex conjugate ghost pair at higher energies. The ghost pair evades easy experimental detection and a nonperturbative reinterpretation of the triviality Higgs mass bound becomes necessary.
119942970
LATTICE STUDY OF SCALAR AND TENSOR GLUEBALLS
118639447
Pure gauge glueballs at finite temperature
Pure gauge glueballs at finite temperature are investigated in a large temperature range from 0:3Tc to 1:9Tc on anisotropic lattices. Optimized glueball operators are used to obtain better signals. It is found in all 20 symmetry channels that the pole masses MG of glueballs remain almost constants when the temperature approaches the critical temperature Tc from below, and start to reduce gradually with the temperature going above Tc. The glueball correlators in 0 ++ , 0 i+ , and 2 ++ channels, are also analyzed based on the Breit-Wigner ansatz by assuming a thermal width Γ to the pole mass ω0. While ω0's are insensitive to T in the whole temperature range, Γ's exhibit distinct behavior below and above Tc: They are only few percents of ω0 when T Tc and reach values of roughly Γ » ω0=2 at T … 1:9Tc.
121608815
Mean-field calculations for the three-dimensional Holstein model
The electron-phonon Holstein model is studied in three spatial dimensions. It is argued that this model can be used to account for major features of the high-Tc BaPb1-xBixO3 and BaxK1-xBiO3 systems. Mean-field calculations are performed via a path integral representation of the model. Charge-density-wave order parameters and transition temperatures are obtained.
15893526
QCD sum rules for masses of excited heavy mesons
Abstract The masses of excited heavy mesons are studied with sum rules in the heavy quark effective theory. A set of interpolating currents creating (annihilating) excited heavy mesons with arbitrary spin and parity are proposed and their properties are discussed. Numerical results at the leading order of the O( 1 m Q ) expansion are obtained for the lowest doublets (0+, 1+) and (1+, 2+).
117850429
Degeneration and gluing of Kuranishi structures in Gromov-Witten theory and the degeneration/gluing axioms for open Gromov-Witten invariants under a symplectic cut
We study the degeneration and the gluing of Kuranishi structures in Gromov-Witten theory under a symplectic cut. This leads us to a degeneration axiom and a gluing axiom for open Gromov-Witten invariants. They provide then a route to the construction of virtual fundamental chains via specialization. Comments on the equivalence of the degeneration formula of closed Gromov-Witten invariants by Li-Ruan/Li versus Ionel-Parker are given in the Appendix.
15866548
Azumaya structure on D-branes and resolution of ADE orbifold singularities revisited: Douglas-Moore vs. Polchinski-Grothendieck
In this continuation of [L-Y1] and [L-L-S-Y], we explain how the Azumaya structure on D-branes together with a netted categorical quotient construction produces the same resolution of ADE orbifold singularities as that arises as the vacuum manifold/variety of the supersymmetric quantum field theory on the D-brane probe world-volume, given by Douglas and Moore [D-M] under the string-theory contents and constructed earlier through hyper-K\"{a}hler quotients by Kronheimer and Nakajima. This is consistent with the moral behind this project that Azumaya-type structure on D-branes themselves -- stated as the Polchinski-Grothendieck Ansatz in [L-Y1] -- gives a mathematical reason for many originally-open-string-induced properties of D-branes.
119507247
Storage of Ultracold Neutrons in the Magneto-Gravitational Trap of the UCN Experiment
The UCN experiment is designed to measure the lifetime n of the free neutron by trapping ultracold neutrons (UCN) in a magneto-gravitational trap. An asymmetric bowl-shaped NdFeB magnet Halbach array confines low-field-seeking UCN within the apparatus, and a set of electromagnetic coils in a toroidal geometry provides a background holding field to eliminate depolarization-induced UCN loss caused by magnetic field nodes. We present a measurement of the storage time store of the trap by storing UCN for various times and counting the survivors. The data are consistent with a single exponential decay, and we find store = 860 19 s, within 1 of current global averages for n. The storage time with the holding field deactivated is found to be store = 470 160 s; this decreased storage time is due to the loss of UCN, which undergo Majorana spin flips while being stored. We discuss plans to increase the statistical sensitivity of the measurement and investigate potential systematic effects.
16420888
MeV tau neutrino in a gauge-mediated supersymmetry breaking model
A supersymmetric model which naturally accommodates MeV tau neutrinos within the framework of gauge-mediated supersymmetry breaking is described. The lepton number violation is originally introduced in the messenger sector of the theory. A large slepton-Higgs mixing mass and a small lepton-higgsino mixing mass are generated at one loop. The scalar tau neutrino has a non-vanishing vacuum expectation value. This results in a non-zero vτ mass which is in the range of 1–10 MeV.