161 research outputs found

    Implication of the proton electric FF space-like behavior puzzle in various physical phenomena

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    By means of the 10-resonance unitary and analytic model of nucleon electromagnetic structure it is demonstrated that the JLab proton polarization data on the ratio μpGEp(Q2)/GMp(Q2)\mu_p G_{Ep}(Q^2)/G_{Mp}(Q^2) are consistent with all form factor properties, however, they strongly require an existence of the zero in G_{Ep}(Q^2) around Q^2=13 GeV^2. As a result there are two contradicting behaviors of G_{Ep}(Q^2) in space-like region. Consequences of this phenomenon on the charge distribution within the proton, on the saturation of the new proton-neutron q^2-dependent sum rule, on the behavior of strange nucleon form factors and the deuteron elastic structure functions through the impulse approximation are investigated.Comment: Talk given at XLI PNPI Winter School in Repino 19-25 February 200

    Strange Vector Form Factor of Kaons

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    Starting from the ω\omega-ϕ\phi mixing, further assuming the coupling of the quark-current of some flavour to be of universal strenth exclusively to the component of vector-meson wave function with the same flavour and finally taking numerical values of the coupling constant ratios (fωKKˉ/fωe)(f_{\omega K \bar K}/f_{\omega}^e), (f_{\phi K\bar K/f_{\phi}^e) from the isoscalar part of a realistic six-resonance unitary and analytic model of the kaon electromagnetic structure, the strange-quark vector current form factor behaviour of K-mesons in space-like and time-like regions is predicted.Comment: Latex, 11 pages, 3 figure

    Two-Photon Decay Rates of True Neutral Pseudoscalar Mesons from Data on their Transition Form Factors

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    By means of the universal unitary and analytic model of electromagnetic structure of hadrons the two-photon decay rates of P=pi^0, eta, eta' mesons are determined in an alternative way from data on their transition form factors.Comment: 7 pages, 6 eps figures. Lecture given at Hadron Structure and QCD: from LOW to HIGH energies, Gatchina, Russia, July 5 - July 9, 201

    Unitary and Analytic Models in Particle Physics Phenomenology

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    After two decades of a development of the unitary and analytic models of the electromagnetic structure of hadrons and nuclei their main principles are briefly formulated, then a general scheme of their applications to the electromagnetic, weak and strong interaction processes are traced out and finally, some results of their successful applications are reviewed.Comment: Latex, 30 pages, 23 figures. Presented at the Hadron Hadron Structure 2000 Conference, October 2-7 2000, Stara Lesna, High Tatra Mountains, Slovak Republi

    Pion scalar form factor and model independent values of f0(500)f_0(500) and f0(980)f_0(980) meson parameters

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    The pion scalar form factor along with all existing S-wave iso-scalar ππ\pi\pi-scattering phase shift data in the elastic region up to 1GeV21 {\rm GeV}^2 are applied for a determination of the f0(500)f_0(500) and f0(980)f_0(980) meson parameters mf0(500)=(360±33)MeVm_{f_0(500)}=(360\pm33){\rm MeV}, Γf0(500)=(587±85)MeV\Gamma_{f_0(500)}=(587\pm 85){\rm MeV} and mf0(980)=(957±77)MeVm_{f_0(980)}=(957\pm77) {\rm MeV}, Γf0(980)=(164±142)MeV\Gamma_{f_0(980)}=(164\pm142){\rm MeV} in a model independent way.Comment: 13 pages, 3 figures, submitted to Phys.Rev.

    Sum rules for total cross-sections of hadron photoproduction on pseudoscalar mesons

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    Sum rules are derived relating mean squared charge radii of the pseudoscalar mesons with the convergent integral of the difference of hadron photoproduction cross-sections on pseudoscalar mesons.Comment: LaTeX, 5 pages, 1 figur

    Ground state 1/2+1/2^+ octet baryon sum rules predicting a chain of inequalities for hadron photoproduction total cross-sections on corresponding baryons

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    Sum rules are derived relating Dirac mean square radii and anomalous magnetic moments of various couples of the ground state 1/2+1/2^+ octet baryons with the convergent integral of the difference of hadron photoproduction cross-sections on the corresponding baryons. Taking into account the present knowledge of static parameters of baryons a chain of inequalities for total hadronic photoproduction cross-sections on baryons is found from those sum rules.Comment: Revtex, 9 pages, 1 figur

    Numerical values of fFf^F, fDf^D, fSf^S coupling constants in SU(3)SU(3) invariant interaction Lagrangian of vector-meson nonet with 1/2+1/2^+ octet baryons

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    It is demonstrated how an utilization of all existing experimental information on electric and magnetic nucleon form factors, to be described by the Unitary and Analytic (U\&A) nucleon electromagnetic structure model in space-like and time-like regions simultaneously, can provide numerical values of fFf^F, fDf^D, fSf^S coupling constants in SU(3)SU(3) invariant interaction Lagrangian of the vector-meson nonet with 1/2+1/2^+ octet baryons. The latter, together with universal vector-meson coupling constants fVf_V, play an essential role in a prediction of 1/2+1/2^+ octet hyperon electromagnetic form factors behaviors.Comment: 41 pages, 25 figure

    Remarkable suppression of the e+eπ+πe^{+}e^{-}\to\pi^{+}\pi^{-} contribution error into muon g2g-2

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    We use the unitary and analytic model of the pion electromagnetic form factor in order to evaluate in the lowest order the e+eπ+πe^{+}e^{-}\to\pi^{+}\pi^{-} contribution into the muon magnetic anomaly. We demonstrate, that this technique enables us to reduce the uncertainty of the theoretical prediction importantly in comparison to usual approaches, where the measured data are integrated directly.Comment: 5 Latex pages,1 figure. Talk at the HSQCD 2009 Int. Conference, Tatranska Strba, 29.8.3.9.2009, Slovak Republi

    Strange-Quark Vector Current Pseudoscalar-Meson Transition Form Factors

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    Similarly to the electromagnetic pseudoscalar-meson transition form factors one can define also strange-quark vector current pseudoscalar-meson transition form factors, contributing only to a behaviour of the isoscalar parts of the previous ones. Their explicit form is found by constructing unitary and analytic models of the strange pseudoscalar-meson transition form factors dependent only on ω\omega and ϕ\phi coupling constant ratios as a free parameters. Numerical values of these ratios are then determined from the corresponding pseudoscalar-meson transition form factors by employing the ω\omega-ϕ\phi mixing and a special assumption on the coupling of the quark components of vector-meson wave functions to flavour component of currents under consideration.Comment: 6 eps figures, Contribution presented at NAPP'03, May 26-31, 2003, Dubrovnik, Croati
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