14249395
On a separatrix in the gravitational collapse to an overcritical electromagnetic black hole
Abstract The dynamical properties of an electron–positron–photon plasma created by the vacuum polarization process occurring around a charged gravitationally collapsing core of an initially neutral star are examined within the framework of general relativity and quantum field theory. The Reissner–Nordstrom geometry is assumed to apply between the collapsing core and the oppositely charged remnant of the star. The appearance of a separatrix at radius R , well outside the asymptotic approach to the horizon, is evidenced. The neutral electron–positron–photon plasma created at radii r> R self-propels outwards to infinity, following the classical PEM–pulse analysis [1,2]. The plasma created at r R remains trapped and follows the gravitational collapse of the core only contributing to the reduction of the electromagnetic energy of the black hole and to the increase of its irreducible mass. This phenomenon has consequences for the observational properties of gamma-ray bursts and is especially relevant for the theoretical prediction of the temporal and spectral structure of the short bursts.
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.
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.
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.
118315524
A Search for New Quarks and Leptons From $\Z^0$ Decay
A search for Z0 decays into pairs of possible new heavy quarks (t and b′), new heavy charged leptons (L±), stable heavy neutral leptons (νL) and unstable heavy neutral leptons (L0) is performed on data collected by the ALEPH detector corresponding to 11 550 events of Z0→hadrons. The limits on the masses of the heavy quarks are Mt > 45.8 GeV and Mb′ > 46.0 GeV, allowing for both charged-current and flavor-changing neutral-current decays of the b′. If an L± decays into a stable νL, then for MνL MνL. Finally, while the mass of the stable νL is excluded up to 42.7 GeV, the mass of the unstable L0 is excluded up to 45.7 GeV with the mixing parameters |UlL0|2 down to 10−13 at this mass. For 25.0 GeV < ML0 < 42.7 GeV, all values of |UlL0|2 are excluded. All limits are given at 95% CL.
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.
104230837
tau mass measurement from e mu, e pi and (mu pi, mu mu, pi pi) channels at BES/BEPC
125590985
Experimental study of f0(975) in J / psi decays
125260045
Evidence of sigma particle in J / psi ---> omega pi pi