115,138 research outputs found
Can low-lying Roper states be explained as antidecuplet members?
It is shown that the anomalously low-lying Roper states cannot be assigned as
pentaquarks with the scalar diquark - scalar diquark - antiquark structure as
suggested by Jaffe and Wilczek.Comment: Will appear in Phys. Rev. Lett. as a comment on the paper by R. Jaffe
and F. Wilczek, Phys. Rev. Lett., 91, 232003 (2003
Why the OZI rule is so strongly violated in J/Psi decays?
The new meson recently observed by BES collaboration in
-decay, is seen only in the OZI-forbidden channel. It is shown that
chiral symmetry restoration in excited hadrons implies a new selection rule of
dynamical origin that forbids some of the OZI-favoured mechanisms of decays.
Hence decays into channels that are suppressed by OZI can become dominant.Comment: 5 pages, 5 figures. The paper has been expanded. A new figure as well
as implications of chiral symmetry for the search of missing a_0 mesons in
charmonium decays have been added. To appear in Phys. Rev.
Optimization of a linear inductive MHD machine considering the longitudinal end effect
Optimization of linear inductive magnetohydrodynamic machine considering longitudinal end effec
Non-dipole angular anisotropy parameters of semi-filled shell atoms
We present the results of calculations of outer shell non-dipole angular
anisotropy parameters for semi-filled shell atoms in the Hartree-Fock (HF)
one-electron approximation and with account of inter-electron correlations in
the frame of the Spin Polarized Random Phase Approximation with Exchange (SP
RPAE). We demonstrate for the first time that this characteristic of
photoionization process is essentially sensitive to the fact whether the
photoelectron has the same or opposite spin orientation to that of the
semi-filled shell.Comment: 15 pages, 8 figure
Large-scale magnetic fields, curvature fluctuations and the thermal history of the Universe
It is shown that gravitating magnetic fields affect the evolution of
curvature perturbations in a way that is reminiscent of a pristine
non-adiabatic pressure fluctuation. The gauge-invariant evolution of curvature
perturbations is used to constrain the magnetic power spectrum. Depending on
the essential features of the thermodynamic history of the Universe, the
explicit derivation of the bound is modified. The theoretical uncertainty in
the constraints on the magnetic energy spectrum is assessed by comparing the
results obtained in the case of the conventional thermal history with the
estimates stemming from less conventional (but phenomenologically allowed)
post-inflationary evolutions.Comment: 21 pages, 6 included figure
Using the reverse path multi-input-single-output method to identify nonlinear characteristics in the apparent mass: preliminary results
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