1,571 research outputs found
Hidden strangeness in nucleons, magnetic moments and SU(3)
The role of nonvalence, e.g., sea quarks and/or meson degrees of freedom in
static electroweak baryon observables is briefly discussed.Comment: 8 pages, Latex, no figures; prepared for Mini-Workshop on Hadron
Structure with Quark Dynamics, Dec.8,2001, Kobe University, Kobe, Japan; FHD
Proceedings, March 2002, Kobe University, Kobe, Japa
Hadron spectroscopy based on relativistic Schr\"odinger-like wave equations
Relativistic potential-type equations are proposed which approximately
reproduce important features and constraints of field-theoretic models and can
be useful tool in hadron spectroscopy. Within this approach, the
Regge-trajectory parameters and some properties of hihger radial excitations in
the light quark sector are discussed.Comment: 7 pages, Latex, no figures; Talk given at the NUPPAC'99, 13-17
November 1999, Cairo, Egyp
On Mesoatoms of the Deuterium and Possible Existence of Exotic Dibaryons
As a desirable supplement to the reaction , proposed
earlier (nucl-th/9712064 and references therein) to probe for the NN--decoupled
dibaryon resonances we suggest to use for the same goal the radiative capture
processes in mesoatoms of the deuterium which we consider to be especially
feasible for further test and invesigation of possible low-lying exotic
resonance states.Comment: LaTex, 5 pages, no figures; Talk at the International Workshop
"Hadronic Atoms and Positronium in the Standard Model", Joint Institute for
Nuclear Research, Dubna, Russia, May 26-31, 199
Quark-Hadron Duality in Photoabsorption Sum Rules and Two Photon Decays of Meson Resonances
The idea of quark-hadron duality is developed and applied to integral sum
rules for the photoexcitation of meson resonances. Some applications of the
presented approach in the light and heavy quark sectors are made, and the role
of the scalar diquark cluster degrees of freedom in the radiative formation of
light scalar mesons is discussed.Comment: 7 pages, Latex, no figures; Talk given at the 2nd International
Symposium on the Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the
Nucleon, Genova, Italy, July 3-6, 200
Radiative processes of nucleon interactions and possible existence of exotic dibaryons
The cross section of the reaction is estimated and
the exploration possibilities of this reaction to probe for a possible
excitation of subnuclear degrees of freedom in two-nucleon systems, in
particular, the production and decay of the NN-decoupled dibaryon resonances,
are briefly discussed.Some arguments for and implications of the intermediate
dibaryon resonance excitation are inferred from preliminary data on the
two-photon yield and energy distribution observed by the DIBAR2 -
Collaboration at the kinetic energy of the initial proton .Comment: 7 pages, Latex, no figures, Talk given at the 13th International
Seminar "Relativistic Nuclear Physics and Quantum Chromodynamics", Dubna, 2-7
Sept. 1996, and at International Workshop "Symmetry and Spin", Prague, 24-30
August 199
Photoabsorption sum rules and quark structure parameters of hadrons
Following the idea of the quark-hadron duality we present, within the
constituent quark model approach, the relations between different
bremsstrahlung-weihgted integrals of the nucleon resonance photoexcitation
cross sections and correlation functions of the quark dipole moments in the
nucleon ground state. These functions are of interest for checking detailed
quark-configuration structure of the nucleon state vector. Some applications of
this approach in meson sector are made and the role of meson degrees of freedom
in the electromagnetic baryon observables is briefly discussed.Comment: LaTex, 8 pages, no figures; Talk at the International Conference
"Hadron Structure 2000", Stara Lesna, High Tatra Mountains, Slovak Republic,
2-7 October 200
On radiative widths and a pattern of quark-diquark-gluon configuration mixing in low-lying scalar mesons
The earlier suggested and developed idea of quark-hadron duality, underlying
"bremsstrahlung-weighted" sum rules for total or polarized photon interaction
cross sections, is applied to the description of excitation of light scalar
mesons in gamma-gamma interactions. The emphasis is put on the discussion of a
role of the scalar diquark cluster degrees of freedom in the radiative
formation of light scalar mesons.Comment: 6 pages, espcrc2.sty, no figures; Talk given at the 12th
International Conference "Selected Problems of Modern Physics", Dedicated to
the 95th anniversary of the birth of D.I. Blokhintsev (1908-1979), Dubna,
Russia, 8-11 June, 200
Electroweak moments of baryons and hidden strangeness of the nucleon
The phenomenological sum-rule-based approach is used to discuss the quark
composition dependence of some static electroweak characteristics of
baryons.The role of nonvalence degrees of freedom (the sea partons and/or
peripheral meson currents) is shown to be important to select and make use of
the relevant symmetry parametrization of baryon observables.The implications of
the baryon magnetic moment analysis for estimation of the q values of
the spin-dependent DIS on nucleons, the contribution of hidden strangeness to
the nucleon magnetic moment and to the quark-line-rule violating -
production in antinucleon-nucleon annihilation reaction are presented.Comment: LaTex, 8 pages, no figures; talk given at the 2nd ELFE Workshop on
Hadronic Physics, Saint Malo, France, 23-27 September, 1996; the abstract is
slightly enlarged compared with the journal versio
On Valence Gluons in Heavy Quarkonia
To include the explicit valence gluon degrees of freedom into spectroscopy of
the lowest states of heavy quarkonia, we consider, within an adiabatic model,
the properties of the lowest hybrid -mesons and estimate the effects
of their mixing with low-lying vector -charmonia. The perspectives of
compatibility of the resulting picture with data are discussed.Comment: LaTex, 5 pages, no figures; Talk at the XIth International Conference
on Problems of Quantum Field Theory, dedicated to 90th anniversary of
Professor D.I. Blokhintsev, Joint Institute for Nuclear Research, Dubna,
Russia, July 13-17, 199
Further remarks on electroweak moments of baryons and manifestations of broken SU(3)
The role of nonvalence, {\it e.g.} sea quarks and/or meson degrees of freedom
in static and quasistatic baryon electroweak observables, is discussed within
the phenomenological sum rule approach. The inclusion of nonvalence degrees of
freedom in the analysis of baryon magnetic moments explains extremely strong
violation of the standard SU(6) symmetry-based quark-model prediction for the
magnetic moment ratio , while the value corresponds to the nonrelativistic quark model. We also
obtain for the quark-current-baryon coupling ratio. The
implications for the "strangeness" magnetism of the nucleon and for weak
axial-to-vector coupling constant relations measured in the lowest octet baryon
-decays are discussed. The latter shows up the possible role of the
induced second-class form factor (the "weak- electricity", or pseudotensor form
factor) in the extraction of the -values from the hyperon's
-decay data.Comment: 6 pages, LaTex, no figures; Talk at the Xth Advanced Research
Workshop on High Energy Spin Physics (Dubna-SPIN-03), Sept. 16-20, 2003,
Dubna, Russia; to appear in the Proceeding
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