979 research outputs found
Appearance of quark-hadron duality in the Rein-Sehgal model
Quark-hadron duality in neutrino-nucleon reactions is investigated under the
assumption that cross sections in the resonance region are given by the
Rein-Sehgal model. The quantitative analysis of the duality is done by means of
appropriate integrals of the structure functions in the Nachtmann variable. We
conclude that with the definition of the resonance region
GeV) the duality holds for neutrino-proton reaction structure function
for GeV and it is absent for neutrino-neutron reaction.Comment: 4 pages, 7 figures, presented at NuInt05 conference, Okayama, Sept.
26-29, 200
Spectral functions for medium-sized nuclei
The spectral functions for calcium and argon are constructed. It is verified
that their predictions for the quasielastic electron-nucleus cross sections in
the energy range ~1 GeV agree with the data. The argon spectral function is
then used to obtain the quasielastic neutrino-nucleus cross section.Comment: 3 pages, 3 figures, presented at 5th International Workshop on
Neutrino-Nucleus Interactions in the Few-GeV Region (NuInt07), Fermilab, USA,
30.05-3.06.200
Theory of STM junctions for \pi-conjugated molecules on thin insulating films
A microscopic theory of the transport in a scanning tunnelling microscope
(STM) set-up is introduced for \pi-conjugated molecules on insulating films,
based on the density matrix formalism. A key role is played in the theory by
the energy dependent tunnelling rates which account for the coupling of the
molecule to the tip and to the substrate. In particular, we analyze how the
geometrical differences between the localized tip and extended substrate are
encoded in the tunnelling rate and influence the transport characteristics.
Finally, using benzene as an example of a planar, rotationally symmetric
molecule, we calculate the STM current voltage characteristics and current maps
and analyze them in terms of few relevant angular momentum channels.Comment: 19 pages, 12 figures, minor changes to conform to published versio
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