14291370
The twisted Wilson fermion for the Standard Model on a lattice
Abstract We present a preliminary study of a chiral-gauge-invariant Wilson term for the Standard Model on a lattice. In the strong coupling limit for doublers, this Wilson term shows that the doublers of leptons (baryons) are antibaryons (anti-leptons), and they are decoupled by getting gauge invariant masses. We discuss that the possibility of achieving the low-energy Standard Model could be realized by the “three-fermion-cuts” at the weak coupling limit for normal modes, where baryons and anti-baryons dissolve into their constituents.
18392606
On evolution of the pair-electromagnetic pulse of a charged black hole
Using hydrodynamic computer codes, we study the possible patterns of relativistic expansion of an enormous pair-electromagnetic-pulse (P.E.M. pulse); a hot, high density plasma composed of photons, electron-positron pairs and baryons deposited near a charged black hole (EMBH). On the bases of baryon-loading and energy conservation, we study the bulk Lorentz factor of expansion of the P.E.M. pulse by both numerical and analytical methods.
124770809
The Casimir Effect in Perfectly Conducting Rectangular Cavity
204932941
GRB 050315: A step toward the uniqueness of the overall GRB structure and the true nature of long GRBs
Using the Swift data of GRB 050315, we progress on the uniqueness of our theoretically predicted Gamma-Ray Burst (GRB) structure as composed by a proper-GRB (P-GRB), emitted at the transparency of an electron-positron plasma with suitable baryon loading, and an afterglow comprising the so called "prompt emission" as due to external shocks. Thanks to the Swift observations, we can theoretically fit detailed light curves for selected energy bands on a continuous time scale ranging over 10^6 seconds. The theoretically predicted instantaneous spectral distribution over the entire afterglow confirms a clear hard-to-soft behavior encompassing, continuously, the "prompt emission" all the way to the latest phases of the afterglow. Consequences of the instrumental threshold on the definition of "short" and "long" GRBs are discussed.
123753224
PHASE-STRUCTURE OF THE SU(2)-SO(3) LATTICE SYSTEM IN AN IMPROVED VARIATIONAL APPROACH
An improved trial action in the variational approach of the lattice gauge field theory is in-troduced to acquire better lower bound for the convexity Inequality and used to calculate the phase structure of the SU(2)-SO(3) pure gauge system. The improvement is seen in comparing the old and new variational results with that by the Monte Carlo simulation.
119482142
The Dynamical Casimir Effect and Energetic Sources for Gamma Ray Bursts
On the analogy of the Casimir effect, we present an effect of quantum-field fluctuations, attributed to gravitational field coupling to the zero-point energy of virtual particles in the vacuum. In the process of black hole's formation, such an effect could cause tremendous energy release, possibly describing a scenario of energetic sources for observed gamma ray bursts.
118787981
Tau and Charm Physics at BES/BEPC
119640767
Measurement of the final states omega pi0, rho eta, and rho eta prime from psi (2S) electromagnetic decays and e+e- annihilations
Cross sections and form factors for $\ee \to \wpi$, $\rho\eta$, and $\rho\etap$ at center of mass energies of 3.650, 3.686, and 3.773 GeV are measured using data samples collected with the BESII detector at the BEPC. Also, the branching fractions of $\psi(2S) \rar \wpi$, $\rho\eta$, and $\rho\etap$ are determined to be $(1.87^{+0.68}_{-0.62}\pm0.28)\times 10^{-5}$, $(1.78^{+0.67}_{-0.62}\pm0.17)\times 10^{-5}$, and $(1.87^{+1.64}_{-1.11}\pm0.33)\times10^{-5}$, respectively.
144007210
A precise determination of the number of families with light neutrinos and of the Z boson partial widths
More extensive and precise results are reported on the parameters of Z decay. On the basis of 20 000 Z decays collected with the ALEPH detector at LEP we find Mz=91.182±0.026 (exp.) ±0.030 (beam) GeV, Γz=2.541±0.056 GeV and σhad0=41.4±0.8 nb. The partial widths for the hadronic and leptonic channels are Γhad=1804±44 MeV, Γe+e−=82.1±3.4 MeV, Γμ+μ−=87.9±6.0 MeV and Γτ+τ−=86.1±5.6 MeV, in good agreement with the standard model. On the basis of the average leptonic width Γl+l−=83.9±2.2 MeV, the effective weak mixing angle is found to be sin2θw(Mz)=0.231±0.008. Usin g the partial widths calculated in the standard model, the number of light neutrino families is Nν=3.01±0.15 (exp.)±0.05 (theor.).
121707912
A study of two-photon production of two-body final states with invariant mass greater than 2.0 GeV
Abstract We have measured the electron, muon, and charged-hadron pair production rates in two-phonon interactions for invariant masses above 2.0 GeV over a large of momentum transfer. The cross sections for electron and muon pairs show good agreement with the QED predictions at both small and large momentum transfer. The observed rate of hadron production is less than 6% of the rate that QED predicts for point-like hadrons, consistent with recent leading-order QCD calculations.
121984352
The BES detector
Abstract The Beijing Spectrometer (BES) is a general purpose solenoidal detector at the Beijing Electron Positron Collider (BEPC). It is designed to study exclusive final states in e + e − annihilations at the center of mass energy from 3.0 to 5.6 GeV. This requires large solid angle coverage combined with good charged particle momentum resolution, good particle identification and high photon detection efficiency at low energies. In this paper we describe the construction and the performance of BES detector.