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Showing 1 to 14 of 14 for “"Pomeron"”.
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Exclusive Pomeron- and Odderon induced photoproduction of omega- and f2 mesons at HERA
… process is thought to be induced by photon-Pomeron interactions, and its cross section is measured to be $sigma(gpoomega p)=(1.3 pm 0.2(ext{stat}) pm 0.2(ext{syst})),muext{b}$, where the decay $omegaopigao3gamma$ is used to analyse the events. The diffractive slope $b$ describing the …
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The reaction pi-p -> pi-pi+pi-p at 147 GeV/c
… ub and 407 ub. There is no evidence for double pomeron exchange; however, the data is not inconsistent with a double pomeron exchange cross section of ~20 ub. Non-diffractive processes are found to contribute only 10 -20 ub to this reaction at 147 GeV/c.
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Diffraction in electron-proton collisions
… processes can be described by the exchange of a pomeron, which is well-known from the phenomenology of highenergy hadron scattering but far from being understood in the framework of quantum chromodynamics. We use the simple model of Landshoff and Nachtmann, where the pomeron is approximated by …
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Measurement of Polarized Proton-Proton Elastic Scattering at the Relativistic Heavy Ion Collider (RHIC)
… interactions are the virtual photon and the <em>Pomeron</em> exchange, respectively. The difficulty of elastic <em>pp</em> scattering arises from the fact that the nature of the <em>Pomeron</em> and its exchange are not well understood and need a theoretical approach, which is still under …
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Rapidity gap in the final state hadron distribution in deep inelastic electron scattering at HERA
… are made with the theoretical predictions of the pomeron and hard diffraction models.
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Spin Dependence in Polarized Proton-Proton Elastic Scattering at RHIC
… at small<em>-t</em> is dominated by the Pomeron exchange, treated in pQCD as a color singlet combination of two gluons carrying quantum numbers of the vacuum (<em>J<sup>PC</sup></em> = 0<sup>++</sup>). In this dissertation, I report on a high precision measurement of the transverse single …
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Electroproduction of the Phi(1020) Vector Meson at 4 GeV
… and well-described by the phenomenological Pomeron-exchange model. Our cross-section data do not favor the standard Vector Meson Dominance and 𝑠𝑠̅-knockout model predictions. From the angular distribution of the decay 𝜙 → 𝐾⁺𝐾⁻, assuming the 𝑠-channel helicity conservation, we extracted the …
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Gluon propagator in classical color field of colliding hadrons and its implications for hadronic cross sections
… and a soft component due to the exchange of the Pomeron and the I=0 exchange-degenerate [omega] and f Regge trajectories. The soft-component model is motivated by the notion of duality. The predicted total cross section has a ln s asymptotic behavior.
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Soft diffractive high energy scattering and form factors in nonperturbative QCD
… the respective final state we get either C=P=+1 (pomeron) oder C=P=-1 (odderon) exchange. Furthermore we calculate the isovector form factors of the proton and the pion at space-like momentum transfers. In the final chapter we use a dispersion approach to calculate the pion form factor at …
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Electroproduction of Phi(1020) Mesons at High Q² with CLAS
… of the Jean-Marc Laget(JML) model based on Pomeron plus 2-gluon exchange. The overall scaling of the total cross section was determined to be 1/Q<sup>4.6±1.7</sup> which is compatible within errors to the Vector Meson Dominance prediction of 1/Q⁴ as well as to the expected behavior of a …
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Um modelo partônico para a difração aplicado ao DIS
… pela troca da trajetória de Regge dominante, o Pomeron, ou por interações perturbativas descritas pela QCD. OS dados existentes não permitem distingüir qual a dominância e possivelmente há uma mistura de efeitos perturbativos QCD e não-perturbativos (Regge). Neste trabalho contrapomos o modelo …
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Investigation of Exclusive Photoproduction of eta-rho0 and pi0-rho0 Meson Pairs at HERA
… are consistent with a contribution from Pomeron exchange.\\ In the analysis of photoproduced $\pin-\rho^{0}$ meson pairs no significant $\rho$ meson signal can be extracted. % the signal of the $\rho^{0}$ meson can not exctracted. Therefore only an upper limit of the cross section is …
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Measurement of the Diffractive Structure Function of the Antiproton in Proton-Antiproton Collisions at √s = 1800 and 630 GeV
… results from a study of dijet events by double pomeron exchange and single diffractive events containing a J/ψ meson by the CDF collaboration, and with results from a study of single diffractive dijet events obtained by the UA8 collaboration in pp̄ collisions at √s = 630 GeV are also …