On model-independent analyses of elastic hadron scattering

By means of an almost model-independent parametrization for the elastic hadron-hadron amplitude, as a function of the energy and the momentum transfer, we obtain good descriptions of the physical quantities that characterize elastic proton-proton and antiproton-proton scattering (total cross section, r parameter and differential cross section). The parametrization is inferred on empirical grounds and selected according to high energy theorems and limits from axiomatic quantum field theory. Based on the predictive character of the approach we present predictions for the above physical quantities at the Brookhaven RHIC, Fermilab Tevatron and CERN LHC energies.67567

Regge Analysis Of Diffractive And Leading Baryon Structure Functions From Deep Inelastic Scattering

In this paper we present a combined analysis of the H1 data on leading baryon and diffractive structure functions from DIS, which are handled as two components of the same semi-inclusive process. The available structure function data are analyzed in a series of fits in which three main exchanges are taken into account: the Pomeron, Reggeon, and pion. For each of these contributions, Regge factorization of the correspondent structure function is assumed. By this procedure, we extract information about the interface between the diffractive, Pomeron-dominated, region and the leading proton spectrum, which is mostly ruled by secondary exchanges. One of the main results is that the relative Reggeon contribution to the semi-inclusive structure function is much smaller than the one obtained from an analysis of the diffractive structure function alone.659 B9600619600610Ahmed, T., (1995) Phys. Lett. B, 348, p. 681Derrick, M., (1995) Z. Phys. C, 68, p. 569Adloff, C., (1999) Eur. Phys. J. C, 6, p. 587Cartiglia, N., hep-ph/9706416http://www-zeus.desy.de/publications.php3Collins, P.D.B., (1977) An Introduction to Regge Theory and High Energy Physics, , Cambridge University Press, Cambridge, EnglandBatista, M., Covolan, R.J.M., (1999) Phys. Rev. D, 59, p. 054006Szczurek, A., Nikolaev, N.N., Speth, J., (1998) Phys. Lett. B, 428, p. 383Adloff, C., (1997) Z. Phys. C, 76, p. 613Breitweg, J., (1998) Eur. Phys. J. C, 1, p. 81Ingelman, G., Schlein, P., (1985) Phys. Lett., 152 B, p. 256Covolan, R.J.M., Soares, M.S., (1998) Phys. Rev. D, 57, p. 180Alvero, L., (1999) Phys. Rev. D, 59, p. 074022McDermott, M.F., Briskin, G., (1996) Proceedings of the Workshop "Future Physics at HERA", , edited by G. Ingelman, A. De Roeck, and R. Klanner, DESY, Hamburg, hep-ph/9610245Covolan, R.J.M., Soares, M.S., (1999) Phys. Rev. D, 60, p. 054005Covolan, R.J.M., Soares, M.S., (2000) Phys. Rev. D, 61, pp. 019901EGolec-Biemat, K., Kwieciński, J., Szczurek, A., (1997) Phys. Rev. D, 56, p. 3955Botje, M.A.J., QCDNUM16: A fast QCD evolution program, , Zeus Note 97-066www-h1.desy.de/h1/www/h1work/fit/h1fit.tools.htmlRoyon, C., Schoeffel, L., Bartels, J., Jung, H., Peschanski, R., (2001) Phys. Rev. D, 63, p. 074004Covolan, R.J.M., Montanha, J., Goulianos, K., (1996) Phys. Lett. B, 389, p. 176Goulianos, K., Montanha, J., (1999) Phys. Rev. D, 59, p. 114017Glück, M., Reya, E., Vogt, A., (1992) Z. Phys. C, 53, p. 651Covolan, R.J.M., Montanha, J., Pontes, A.N., Soares, M.S., in preparationBreitweg, J., (1998) Eur. Phys. J. C, 5, p. 41Adloff, C., (1999) Eur. Phys. J. C, 6, p. 421(2001) Eur. Phys. J. C, 20, p. 2

On the slope of the elastic differential cross sections

Making use of a model-independent analytical fit for the elastic hadron-hadron amplitude, recently developed, we investigate the slope of the proton-proton and antiproton-proton differential cross sections, as a function of the energy and the momentum transfer. We show that the predictions for these quantities are in agreement with the experimental data available and discuss the effect of the slope position as function of the momentum transfer.808

Diffractive Contribution to the Elasticity and the Nucleonic Flux in the Atmosphere

We calculate the average elasticity considering non-diffractive and single diffractive interactions and perform an analysis of the cosmic-ray flux by means of an analytical solution for the nucleonic diffusion equation. We show that the diffractive contribution is important for the adequate description of the nucleonic and hadronic fluxes in the atmosphere.Comment: 10 pages, latex, 2 figures (uuencoded PostScript

Regge Analysis of Diffractive and Leading Baryon Structure Functions from DIS

In this paper we present a combined analysis of the H1 data on leading baryon and diffractive structure functions from DIS, which are handled as two components of the same semi-inclusive process. The available structure function data are analyzed in a series of fits in which three main exchanges are taking into account: pomeron, reggeon and pion. For each of these contributions, Regge factorization of the correspondent structure function is assumed. By this procedure, we extract information about the interface between the diffractive, pomeron-dominated, region and the leading proton spectrum, which is mostly ruled by secondary exchanges. One of the main results is that the relative reggeon contribution to the semi-inclusive structure function is much smaller than the one obtained from a analysis of the diffractive structure function alone.Comment: ps file, 22 pages, 5 figures. Totally revised version with major changes, to appear in Physical Review

CONTRAINTERPRETAR O SOCIALISMO E RESSIGNIFICAR A MODERNIDADE: CONTRIBUIÇÕES DE LEONARDO PADURA

No texto a seguir, parto da observação do cenário brasileiro contemporâneo para evidenciar o enfastiado conhecimento político e social que tem a população, o qual proporciona mal-entendidos em relação à esquerda e ao socialismo. Mostra-se urgente, então, uma contrainterpretação do socialismo e, consequentemente, um novo entendimento da modernidade. Um dos caminhos para isso são as manifestações artísticas, incluindo a literatura. Por isso, num segundo momento do texto, analiso de que maneira o autor cubano Leonardo Padura, mais especificamente em El hombre que amaba a los perros, contribui com a contrainterpretação do socialismo e com a ressignificação da modernidade

Phenomenological analysis connecting proton-proton and antiproton-proton elastic scattering

Based on the behavior of the elastic scattering data, we introduce an almost model-independent parametrization for the imaginary part of the scattering amplitude, with the energy and momentum transfer dependences inferred on empirical basis and selected by rigorous theorems and bounds from axiomatic quantum field theory. The corresponding real part is analytically evaluated by means of dispersion relations, allowing connections between particle-particle and particle-antiparticle scattering. Simultaneous fits to proton-proton and antiproton-proton experimental data in the forward direction and also including data beyond the forward direction, lead to a predictive formalism in both energy and momentum transfer. We compare our extrapolations with predictions from some popular models and discuss the applicability of the results in the normalization of elastic rates that can be extracted from present and future accelerator experiments (Tevatron, RHIC and LHC).Comment: 17 pages, 17 figures, to appear in Eur. Phys. J.