119162753
On the gauge features of gravity on a Lie algebroid structure
We present the geometric formulation of gravity based on the mathematical structure of a Lie Algebroid. We show that this framework provides the geometrical setting to describe the gauge propriety of gravity.
117370742
Statistical Mechanics of Wormholes
The statistical mechanics of a gas of Einstein-Kalb-Ramond wormholes is studied in this paper. The wormholes studied are the result of sewing together two Reissner-Nordstrom-type black hole metrics at their horizons. By requiring the stress-energy tensor associated with this geometry to be that of a Kalb-Ramond field, we obtain the mass and Kalb-Ramond `charge` of the wormholes in terms of the parameters describing the mass density, tension and pressure. We investigate the statistical mechanics of this system of wormholes within the context of the statistical bootstrap model. A gas of such wormholes is found to obey the bootstrap condition only for an extreme, non-thermodynamic, energy and `charge` distribution among the particles. We comment briefly on the scattering of quantum wormholes.
123086408
A position sensitive detector for the g-2 experiment using pencil fibers
Abstract An x − y hodoscope using bundles of 2 mm diameter “pencil” fibers (waveshifting fibers embedded in scintillating fibers) mated to smaller diameter clear fibers has been built and tested for use in the new g-2 experiment at Brookhaven. The fibers were read out by a 64-channel Philips XP4722 photomultiplier tube. Data is presented on the light yield, attenuation and fusing efficiency from pencil fibers; the crosstalk, uniformity, rate and linearity of the multichannel tubes; and the overall performance of the device in a test beam.
119276928
Measurement of central exclusive $\pi^+ \pi^-$ production in $p\bar{p}$ collisions at $\sqrt{s} = 0.9$ and 1.96 TeV at CDF
We measure exclusive π+π- production in proton-antiproton collisions at center-of-mass energies s=0.9 and 1.96 TeV in the Collider Detector at Fermilab. We select events with two oppositely charged particles, assumed to be pions, with pseudorapidity |η|<1.3 and with no other particles detected in |η|<5.9. We require the π+π- system to have rapidity |y|<1.0. The production mechanism of these events is expected to be dominated by double pomeron exchange, which constrains the quantum numbers of the central state. The data are potentially valuable for isoscalar meson spectroscopy and for understanding the pomeron in a region of transition between nonperturbative and perturbative quantum chromodynamics. The data extend up to dipion mass M(π+π-)=5000  MeV/c2 and show resonance structures attributed to f0 and f2(1270) mesons. From the π+π- and K+K- spectra, we place upper limits on exclusive χc0(3415) production.