305 research outputs found
Hadronic three-body decays of light vector mesons
The decays of light vector mesons into three pseudoscalar mesons are
calculated to leading order in the recently proposed counting scheme that is
based on the hadrogenesis conjecture. Fully differential as well as integrated
decay widths are presented. Since the required parameters have been fixed by
other processes, the considered three-body decays are predictions of the
presented approach. The decay width of the omega meson into three pions agrees
very well with experiment. The partial decay widths of the K^* into its three
K-pi-pi channels are predicted.Comment: 7 page
Quantum control of the motional states of trapped ions through fast switching of trapping potentials
We propose a new scheme for supplying voltages to the electrodes of
microfabricated ion traps, enabling access to a regime in which changes to the
trapping potential are made on timescales much shorter than the period of the
secular oscillation frequencies of the trapped ions. This opens up
possibilities for speeding up the transport of ions in segmented ion traps and
also provides access to control of multiple ions in a string faster than the
Coulomb interaction between them. We perform a theoretical study of ion
transport using these methods in a surface-electrode trap, characterizing the
precision required for a number of important control parameters. We also
consider the possibilities and limitations for generating motional state
squeezing using these techniques, which could be used as a basis for
investigations of Gaussian-state entanglement.Comment: Accepted by New Journal of Physic
Chiral Partners and their Electromagnetic Radiation -- Ingredients for a systematic in-medium calculation
It is argued that the chiral partners of the lowest-lying hadrons are
hadronic molecules and not three-quark or quark-antiquark states, respectively.
As an example the case of a_1 as the chiral partner of the rho is discussed.
Deconfinement -- or as a precursor large in-medium widths for hadronic states
-- is proposed as a natural way to accommodate for the fact that at chiral
restoration the respective in-medium spectra of chiral partners must become
degenerate. Ingredients for a systematic and self-consistent in-medium
calculation are presented with special emphasis on vector-meson dominance which
emerges from a recently proposed systematic counting scheme for the mesonic
sector including pseudoscalar and vector mesons as active degrees of freedom.Comment: revised version: more references adde
Short-range correlations in quark matter
We investigate the role of short-range correlations in quark matter within
the framework of the SU(2) NJL model. Employing a next-to-leading order
expansion in 1/N_c for the quark self energy we construct a fully
self-consistent model that is based on the relations between spectral functions
and self energies. In contrast to the usual quasiparticle approximations we
take the collisional broadening of the quark spectral function consequently
into account. Mesons are dynamically generated in the fashion of a random phase
approximation, using full in-medium propagators in the quark loops. The results
are self-consistently fed back into the quark self energy. Calculations have
been performed for finite chemical potentials at zero temperature. The
short-range correlations do not only generate finite widths in the spectral
functions but also have influence on the chiral phase transition.Comment: 40 pages, 23 figures; revised and extended paper, accepted for
publication in Phys. Rev.
QCD sum rule analysis for light vector and axial-vector mesons in vacuum and nuclear matter
Extending previous work we study the constraints of QCD sum rules on mass and
width of light vector and axial-vector mesons in vacuum and in a medium with
finite nuclear density. For the latter case especially the effect of nuclear
pions leading to vector-axial-vector mixing is included in the analysis.Comment: RevTeX, 32 pages, 10 eps figure
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