Dvofotonski raspad b i d mezona u modelu prevladavajućih polova

We give a detailed study of the two-gamma decay of some heavy pseudoscalar mesons using the pole-dominance model. The transition matrix elements of PL to bare glueball (G0) are also computed, and it is found that the PL to glueball contribution is comparable with that of PL to π0. From our results, we have obtained the two-gamma decay width of DL and an upper limit of the two-gamma decay widths of BL and BsL mesons.Podrobno se proučavaju dvofotonski raspadi teških pseudoskalarnih mezona na osnovi modela prevladavajućih polova. Izračunavaju se matrični elementi prijelaza PL u golu gluonsku loptu (G0 ) i nalazi da je doprinos tog procesa usporediv s doprinosom prijelaza PL u π 0 . Izračunate su širina dvofotonskog raspada mezona DL i gornje granice širina dvofotonskih raspada BL i BsL mezona

Konstanta vezanja B-mezon – kvark i širina raspada B∗-mezona

The pion - quark coupling constant (gπq q) and the B-meson - quark coupling constant (gB-qq) have been found in the processes B*- → B-π0 and B*- → B-γ. Their decay widths have been calculated through the direct coupling of π0 and B- with quarks which are static inside B*- meson.Određuju se konstante vezanja pion – kvark (gπqq) i B-mezon – kvark (gB−qq) u procesima B∗−→B−π0 i B∗−→B−γ. Njihove se širine raspada računaju preko izravnog vezanja π0 i B− s kvarkovima koji miruju u B∗− mezonu

Die Characterprobleme bei Shakespeare. Eine Einfuhrung in das Verstandnis des Dramatikers

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Routh's procedure for non-Abelian symmetry groups

We extend Routh's reduction procedure to an arbitrary Lagrangian system (that is, one whose Lagrangian is not necessarily the difference of kinetic and potential energies) with a symmetry group which is not necessarily Abelian. To do so we analyse the restriction of the Euler-Lagrange field to a level set of momentum in velocity phase space. We present a new method of analysis based on the use of quasi-velocities. We discuss the reconstruction of solutions of the full Euler-Lagrange equations from those of the reduced equations.Comment: 30 pages, to appear in J Math Phy

To the University of London Graduates' Committee.

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Circular Orbits in Einstein-Gauss-Bonnet Gravity

The stability under radial and vertical perturbations of circular orbits associated to particles orbiting a spherically symmetric center of attraction is study in the context of the n-dimensional: Newtonian theory of gravitation, Einstein's general relativity, and Einstein-Gauss-Bonnet theory of gravitation. The presence of a cosmological constant is also considered. We find that this constant as well as the Gauss-Bonnet coupling constant are crucial to have stability for $n>4$.Comment: 11 pages, 4 figs, RevTex, Phys. Rev. D, in pres

Lipopolysaccharide (LPS) and tumor necrosis factor alpha (TNF[alfa]) blunt the response of Neuropeptide Y/Agouti-related peptide (NPY/AgRP) glucose inhibited (GI) neurons to decreased glucose

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