256,335 research outputs found
Rotating Superconductors and the Frame-independent London Equation
A frame-independent, thermodynamically exact London equation is presented,
which is especially valid for rotating superconductors. A direct result is the
unexpectedly high accuracy () for the usual expression of the
London moment.Comment: 4 pages, 0 figure
Gauge Invariance of the Muonium-Antimuonium Oscillation Time Scale and Limits on Right-Handed Neutrino Masses
The gauge invariance of the muonium-antimuonium () oscillation time
scale is explicitly demonstrated in the Standard Model modified only by the
inclusion of singlet right-handed neutrinos and allowing for general
renormalizable interactions. The see-saw mechanism is exploited resulting in
three light Majorana neutrinos and three heavy Majorana neutrinos with mass
scale . The leading order matrix element contribution to the
oscillation process is computed in gauge and shown to be
independent thereby establishing the gauge invariance to this order.
Present experimental limits resulting from the non-observation of the
oscillation process sets a lower limit on roughly of order 600 GeV.Comment: 17 pages, 6 figures, Late
A Lattice Study of the Glueball Spectrum
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 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: for the
scalar glueball mass and for the tensor glueball.Comment: 10 pages, 2 figures,typos correcte
Jet conversions in a quark-gluon plasma
Quark and gluon jets traversing through a quark-gluon plasma not only lose
their energies but also can undergo flavor conversions. The conversion rates
via the elastic and the inelastic scatterings are evaluated in the lowest order in QCD.
Including both jet energy loss and conversions in the expanding quark-gluon
plasma produced in relativistic heavy ion collisions, we have found a net
conversion of quark to gluon jets. This reduces the difference between the
nuclear modification factors for quark and gluon jets in central heavy ion
collisions and thus enhances the and ratios at high
transverse momentum. However, a much larger net quark to gluon jet conversion
rate than the one given by the lowest-order QCD is needed to account for the
observed similar ratios in central Au+Au and p+p collisions at same energy.
Implications of our results are discussed.Comment: version to appear in PR
Ion mixing to produce amorphous Mo-Ru superconducting films
Amorphous Mo55Ru45 alloy films were formed by ion mixing of multilayered samples. The ion mixed films, which contain no metalloid element, show excellent superconducting properties. The measured properties are correlated with the microstructure obtained by both x-ray diffraction and transmission electron microscopy
Quantum Statistical Entropy and Minimal Length of 5D Ricci-flat Black String with Generalized Uncertainty Principle
In this paper, we study the quantum statistical entropy in a 5D Ricci-flat
black string solution, which contains a 4D Schwarzschild-de Sitter black hole
on the brane, by using the improved thin-layer method with the generalized
uncertainty principle. The entropy is the linear sum of the areas of the event
horizon and the cosmological horizon without any cut-off and any constraint on
the bulk's configuration rather than the usual uncertainty principle. The
system's density of state and free energy are convergent in the neighborhood of
horizon. The small-mass approximation is determined by the asymptotic behavior
of metric function near horizons. Meanwhile, we obtain the minimal length of
the position which is restrained by the surface gravities and the
thickness of layer near horizons.Comment: 11pages and this work is dedicated to the memory of Professor Hongya
Li
Comparison of Canonical and Grand Canonical Models for selected multifragmentation data
Calculations for a set of nuclear multifragmentation data are made using a
Canonical and a Grand Canonical Model. The physics assumptions are identical
but the Canonical Model has an exact number of particles, whereas, the Grand
Canonical Model has a varying number of particles, hence, is less exact.
Interesting differences are found.Comment: 12 pages, Revtex, and 3 postscript figure
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