25,474 research outputs found
Knizhnik-Zamolodchikov-Bernard equations on Riemann surfaces
Knizhnik-Zamolodchikov-Bernard equations for twisted conformal blocks on
compact Riemann surfaces with marked points are written explicitly in a general
projective structure in terms of correlation functions in the theory of twisted
b-c systems. It is checked that on the moduli space the equations provide a
flat connection with the spectral parameter.Comment: 23 page
Deep I-band Imaging of z=5.99 Quasar
Deep I-band imaging was carried out to search for the optical counterpart of
the X-ray jet candidate near SDSS 1306+0356, reported by Schwartz (2002,
astro-ph/0202190). The data suggest that the extended X-ray source may be a
jet, related to a galaxy rather than to the quasar itself.Comment: 2 page letter, accepted for publication in Astronomy and Astrophysics
Slight changes to the figure
QCD Factorization for the Pion Diffractive Dissociation Into Two Jets
We report a detailed study of the process of pion diffraction dissociation
into two jets with large transverse momenta. We find that the standard
collinear factorization does not hold in this reaction. The structure of
non-factorizable contributions is discussed and the results are compared with
the experimental data. Our conclusion is that the existing theoretical
uncertainties do not allow, for the time being, for a quantitative extraction
of the pion distribution amplitude. (Talk presented at the Workshop on
Exclusive Processes at High Momentum Transfer, Jefferson News, VA, May 15-18,
2002)Comment: 6 pages, latex, two figure
Allowed charge transfers between coherent conductors driven by a time-dependent scatterer
We derive constraints on the statistics of the charge transfer between two
conductors in the model of arbitrary time-dependent instant scattering of
non-interacting fermions at zero temperature. The constraints are formulated in
terms of analytic properties of the generating function: its zeroes must lie on
the negative real axis. This result generalizes existing studies for scattering
by a time-independent scatterer under time-dependent bias voltage.Comment: 5 pages, no figures, corrected misprints and minor changes in version
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