770 research outputs found
Neutrino scattering as a probe for the strange content of the nucleon
We consider different methods and observables which can be obtained by the
measurement of neutrino scattering off nucleons and nuclei with the purpose of
finding evidence for the strange form factors of the nucleon, which enter into
structure of the nucleonic weak neutral current.Comment: 8 pages, 2 figures Contribution to 20th Max Born Symposium, Wroclaw
(Poland), December 7-10, 200
Weak non-mesonic decay of Hypernuclei
We review the mechanism of weak decay of hypernuclei, with emphasis on the
non-mesonic decay channels. Various theoretical approaches are discussed and
the results are compared with the available experimental data.Comment: 15 pages, 3 figures, Talk presented at XXVIII Mazurian Lakes
Conference, Krzyze, Poland, August 31-September 7, 2003. To be published in
Acta Physica Pol. B 35 (2004
Weak Decay of Hypernuclei
The focus of these Lectures is on the weak decay modes of hypernuclei, with
special attention to Lambda-hypernuclei. The subject involves many fields of
modern theoretical and experimental physics, from nuclear structure to the
fundamental constituents of matter and their interactions. The various weak
decay modes of Lambda-hypernuclei are described: the mesonic mode and the
non-mesonic ones. The latter are the dominant decay channels of medium--heavy
hypernuclei, where, on the contrary, the mesonic decay is disfavoured by Pauli
blocking effect on the outgoing nucleon. In particular, one can distinguish
between one-body and two-body induced decays. Theoretical models employed to
evaluate the (partial and total) decay widths of hypernuclei are illustrated,
and their results compared with existing experimental data. Open problems and
recent achievements are extensively discussed, in particular the determination
of the ratio Gamma_n/Gamma_p, possible tests of the Delta I=1/2 rule in
non-mesonic decays and the puzzling asymmetric non-mesonic decay of polarized
hypernuclei.Comment: 59 pages, 13 figures Lectures given at the International School of
Physics "Enrico Fermi" Course on: HADRON PHYSICS, Varenna (Lake Como), June
22nd - July 2nd, 200
Screening Masses of Scalar and Pseudo-scalar Excitations in Quark-gluon Plasma
The quark-gluon plasma (QGP) excitations, corresponding to the scalar and
pseudoscalar meson quantum numbers, for different temperatures are calculated.
Analysis is performed in the Hard Thermal Loop (HTL) Approximation and leads to
a better understanding of the excitations of QGP in the deconfined phase and is
also of relevance for lattice studies
On a possibility to determine the S-factor of the hep process in experiments with thermal (cold) neutrons
The problem of the magnitude of the S--factor of the hep process is one of the most important
unsolved problems in nuclear astrophysics. The magnitude of has also
an important impact on the interpretation of the Super-Kamiokande solar
neutrino results in terms of neutrino oscillations. We point out the possiblity
to determine the major hadronic contribution to from the measurement
of the total cross section of the process in experiments with high intensity beams
of thermal or cold neutrons.Comment: 7 pages, revtex, no figures; note added; final version to be
published in Astropart. Phy
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