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Related papers: The Missing Odderon

200 papers

We use power-counting arguments as an organizing principle to apply chiral perturbation theory, including an explicit $\Delta$, to the $p p \rightarrow p p \pi^0$ reaction near threshold. There are two lowest-order leading mechanisms…

Nuclear Theory · Physics 2008-11-26 T. D. Cohen , J. L. Friar , G. A. Miller , U. van Kolck

Utilizing the most recent experimental data, we reanalyze high energy \pbar p and pp data, using the asymptotic amplitude analysis, under the assumption that we have reached `asymptopia'. This analysis gives strong evidence for a $\log…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. M. Block , A. R. White , B. Margolis

The possibility to use the exclusive $pp \to pp \phi$ and $pp \to pp \phi \phi$ reactions in identifying the odderon exchange is discussed. So far there is no unambiguous experimental evidence for the odderon, the charge conjugation $C =…

High Energy Physics - Phenomenology · Physics 2020-12-03 Piotr Lebiedowicz , Otto Nachtmann , Antoni Szczurek

The interplay of pQCD, pion exchange and FSI effects is studied for the gamma gamma --> pi^+ pi^- reaction in the region of 2 GeV < W_{gamma gamma} < 6 GeV. We find strong interference effects between pQCD and soft pion-exchange amplitudes…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. Szczurek , J. Speth

We study the perturbative Odderon in the quasidiffractive process gamma(*) gamma(*) to eta_c eta_c. At high energies this process is dominated by Odderon exchange and can be viewed as the theoretically cleanest test of the perturbative…

High Energy Physics - Phenomenology · Physics 2011-07-19 Stefan Braunewell , Carlo Ewerz

We review the cross sections for low-energy $\pi^- \gamma$ reactions in the framework of chiral perturbation theory. Charged pion Compton scattering, $\pi^- \gamma\to \pi^-\gamma$, is considered up to one-loop order where the pion's…

Nuclear Theory · Physics 2008-11-26 N. Kaiser , J. M. Friedrich

Based on the postulate that a $C$-odd exchange leads to repulsion in the particle-particle system (say, $pp$) and to attraction in the antiparticle-particle system (say, $\bar{p}p$), we show that the Odderon intercept cannot be greater than…

High Energy Physics - Phenomenology · Physics 2025-08-15 Vladimir A. Petrov

Differential cross sections and photon-beam asymmetries for the gamma p -> pi- Delta++(1232) reaction have been measured for 0.7<cos(theta)<1 and Egamma=1.5-2.95 GeV at SPring-8/LEPS. The first-ever high statistics cross section data are…

The strong interaction shift $\epsilon$ and broadening {\Gamma} in pionic deuterium have been determined in a high statistics study of the {\pi}D(3p - 1s) X-ray transition using a high-resolution crystal spectrometer. The pionic deuterium…

It is shown that a recent extraction of the total cross section for pp->K+ n Sigma+ from inclusive K+ production data is in conflict with experimental data on the exclusive pp->K+ p Lambda reaction. The result may be interpreted as an upper…

Nuclear Experiment · Physics 2011-01-04 Yu. Valdau , C. Wilkin

We reinvestigate the experimental data on $\omega$--meson production in pion-nucleon collisions based on both an analytical approach and a Monte Carlo simulation. Our analysis allows us to study the kinematical peculiarities of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Hanhart , A. Sibirtsev , J. Speth

The cross sections of $\Upsilon$ absorption by $\pi$ and $\rho$ mesons are evaluated in a meson-exchange model. Including form factors with a cutoff parameter of 1 or 2 GeV, we find that due to the large threshold of these reactions the…

Nuclear Theory · Physics 2014-11-18 Ziwei Lin , C. M. Ko

The dimensional scaling of the differential cross sections of binary reactions $d\sigma/d t\sim s^{-(n-2)}$, where $n$ is given by constituent quark counting rules, was predicted for asymptotically high energies $\sqrt{s}\gg m_i$ and…

Nuclear Theory · Physics 2016-09-21 Yu. N. Uzikov

We reanalyse $\bar p p$ and $pp$ high energy data of the elastic scattering above $\sqrt{s}=5$ GeV on the total cross-section $\sigma_{tot}$ and on the forward $\rho$-ratio for various models of Pomeron, utilizing two methods. The first one…

High Energy Physics - Phenomenology · Physics 2009-10-30 P. Desgrolard , M. Giffon , E. S. Martynov

Threshold measurements of the associated strangeness production reactions pp --> p K(+) Lambda and pp --> p K(+) Sigma(0) are presented. Although slight differences in the shapes of the excitation functions are observed, the most remarkable…

We consider the $\pi\pi$ scattering amplitude obtained by Colangelo, Gasser and Leutwyler (CGL), using dispersion relations and chiral perturbation theory to two loops. We point out that the input used by CGL for energies above 1.42 GeV is…

High Energy Physics - Phenomenology · Physics 2009-11-10 F. J. Yndurain

Constraints on the spin-averaged $\Lambda p$ scattering length and effective range have been obtained from measurements of the $pp\to pK^+\Lambda$ reaction close to the production threshold by comparing model phase-space Dalitz plot…

We study the pp -> p Lambda K+ and pp -> p Sigma0 K+ reactions near threshold by using a chiral unitary approach. We consider the single-pion and single-kaon exchange as well as the final state interactions of nucleon-hyperon, K-hyperon and…

Nuclear Theory · Physics 2011-08-23 Hua-Xing Chen , Ju-Jun Xie , E. Oset

We have observed the reactions p+pbar --> p+X+pbar, with X being a centrally produced J/psi, psi(2S) or chi_c0, and gamma+gamma --> mu+mu-, in proton- antiproton collisions at sqrt{s} = 1.96 TeV using the Run II Collider Detector at…

High Energy Physics - Experiment · Physics 2009-07-09 CDF Collaboration , T. Aaltonen

We explore the possibility of observing odderon exchange in the $pp \to pp K^{+}K^{-}$ and $pp \to pp \mu^{+}\mu^{-}$ reactions at the LHC. We consider the central exclusive production (CEP) of the $\phi(1020)$ resonance decaying into…

High Energy Physics - Phenomenology · Physics 2020-05-20 Piotr Lebiedowicz , Otto Nachtmann , Antoni Szczurek