8,028 research outputs found
One gluon, two gluon: multigluon production via high energy evolution
We develop an approach for calculating the inclusive multigluon production
within the JIMWLK high energy evolution. We give a formal expression of
multigluon cross section in terms of a generating functional for arbitrary
number of gluons . In the dipole limit the expression simplifies
dramatically. We recover the previously known results for single and double
gluon inclusive cross section and generalize those for arbitrary multigluon
amplitude in terms of Feynman diagramms of Pomeron - like objects coupled to
external rapidity dependent field . We confirm the conclusion that the
AGK cutting rules in general are violated in multigluon production. However we
present an argument to the effect that for doubly inclusive cross section the
AGK diagramms give the leading contribution at high energy, while genuine
violation only occurs for triple and higher inclusive gluon production. We
discuss some general properties of our expressions and suggest a line of
argument to simplify the approach further.Comment: 32 pages, one reference corrected. to appear in JHE
Ginzburg-Landau Expansion and the Slope of the Upper Critical Field in Disordered Superconductors with Anisotropic Pairing
It is demonstrated that the slope of the upper critical field
in superconductors with -wave pairing drops rather
fast with concentration of normal impurities, while in superconductors with
anisotropic -wave pairing grows, and in the limit of
strong disorder is described by the known dependences of the theory of
``dirty'' superconductors. This allows to use the measurements of in
disordered superconductors to discriminate between these different types of
pairing in high-temperature and heavy-fermion superconductors.Comment: 7 pages, 5 figures, RevTeX 3.0, 4 Postscript figures attached;
Submitted to JETP Letter
Multimuons events and primary composition
Nucleon decay detectors at large depths offers now a total area larger than 1000 sq m to registrate muons of energy exceeding 1 TeV. Near complete high energy muon families are detected in those arrays. An extensive 3D Monte-Carlo simulation was conducted in view to understand the spatial distribution of those events and the possible link with elementary act or primary composition. As pion or kaon parents have a very small decay probability at so high energy, multimuon phenomena occurs at high altitude where the atmospheric density is small after the most energetic collisions
Measurement of the - mixing angle in and beams with GAMS- Setup
The results of mixing angle measurement for , mesons generated
in charge exchange reactions with and beams are preseneted.
When the , mesons are described in nonstrange(NS)--strange(S)
quark basis the and beams allow to study and
parts of the meson wave function. The cross section ratio at
(GeV/c) in the beam is , results in mixing angle . For
beam the ratio is . It was found that
gluonium content in is . The
experiment was carried out with GAMS-4 Setup.Comment: 6 pages, 4 figures, 1 table, to be submitted in European physical
journal C. Minor changes, the Bibliography extende
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