3,617,283 research outputs found
Lightest scalar and tensor resonances in after the Belle experiment
New high statistics Belle data on the reaction
cross section measured in the range of pion-pair invariant masses
between 0.8 GeV and 1.5 GeV are analyzed to clarify the current situation
around the , , and resonances in
collisions. The present analysis shows that the direct coupling
constants of the and resonances to are
small, and the and
decays are four-quark transitions caused by the and loop
mechanisms, respectively. The chiral shielding of the resonance
takes place in the reactions as well as in
scattering. Some results of a simultaneous description of the
and Belle data are also
presented. In particular, the following tentative estimate of the
decay width is obtained:
keV.Comment: 14 pages, 5 figures. Fitted for the publication in Physical Review
Proposed Search for Mixing in Polarization Phenomena
The and meson mass difference induces the mixing of the
and resonances, the amplitude of which, between the
and thresholds, is large in magnitude, of the order of , and possesses the
phase sharply varying by about 90. We suggest performing the polarized
target experiments on the reaction at high energy in
which the fact of the existence of mixing can be
unambiguously and very easily established through the presence of a strong jump
in the azimuthal asymmetry of the wave production cross section
near the thresholds. The presented estimates of the polarization
effect to be expected in experiment are to a great extent model independent.Comment: RevTeX, 9 pages, 1 figure. A number of typographical and grammatical
errors correcte
Spin-Spin Interactions in Gauge Theory of Gravity, Violation of Weak Equivalence Principle and New Classical Test of General Relativity
For a long time, it is generally believed that spin-spin interactions can
only exist in a theory where Lorentz symmetry is gauged, and a theory with
spin-spin interactions is not perturbatively renormalizable. But this is not
true. By studying the motion of a spinning particle in gravitational field, it
is found that there exist spin-spin interactions in gauge theory of gravity.
Its mechanism is that a spinning particle will generate gravitomagnetic field
in space-time, and this gravitomagnetic field will interact with the spin of
another particle, which will cause spin-spin interactions. So, spin-spin
interactions are transmitted by gravitational field. The form of spin-spin
interactions in post Newtonian approximations is deduced. This result can also
be deduced from the Papapetrou equation. This kind of interactions will not
affect the renormalizability of the theory. The spin-spin interactions will
violate the weak equivalence principle, and the violation effects are
detectable. An experiment is proposed to detect the effects of the violation of
the weak equivalence principle.Comment: 17 pages, no figur
Light Scalar Mesons as Manifestation of Spontaneously Broken Chiral Symmetry
Attention is paid to the production mechanisms of light scalars that reveal
their nature. We reveal the chiral shielding of the \sigma(600) meson. We show
that the kaon loop mechanism of the \phi radiative decays, ratified by
experiment, points to the four-quark nature of light scalars. We show also that
the light scalars are produced in the two photon collisions via four-quark
transitions in contrast to the classic P wave tensor q\bar q mesons that are
produced via two-quark transitions . The history of
spontaneous breaking of symmetry in quantum physics is discussed in Appendix.Comment: Talk at The International Bogolyubov Conference "Problems of
Theoretical and Mathematical Physics" devoted to the 100th anniversary of
N.N.Bogolyubov's birth that was held from August 21 to August 22,2009 in
Moscow at the Russian Academy of Sciences (RAS) and from August 23 to August
27, 2009 in Dubna at the Joint Institute for Nuclear Research (JINR
Evolution of high-mass diffraction from the light quark valence component of the pomeron
We analyze the contribution from excitation of the Fock states of the photon to high mass diffraction in
DIS. We show that the large behavior of this contribution can be
described by the DLLA evolution from the non-perturbative valence
state of the pomeron. Although of higher order in pQCD, the new contribution to
high-mass diffraction is comparable to that from the excitation of the Fock state of the photon.Comment: 12 pages, 2 figures, the oublished version. The slight numerical
errors corrected, all conclusions are retaine
- …