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

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 Question Of The Energy Dependence Of Inelasticity

We discuss the question of the energy dependence of inelasticity in very-high-energy hadronic interactions. From existing extensive-air-shower data, a definite conclusion cannot yet be reached. However, Glauber model realistic calculations and recent results from Tevatron suggest a slow increase of the mean inelasticity with energy. © 1992.2791-2149152Amos, (1990) Phys. Lett. B, 243, p. 158Bellandi, Mundim, Dias de Deus, Covolan, J. Phys. C (1991) J. Phys. C, , to be publishedBurnett, (1990) Astrophys. J., 349, p. L25Allkofer, (1975) Introduction to cosmic radiation, , Verlag Karl Thiemig, MunichLiland, (1987) Proc. XXth Intern. Cosmic ray Conf., 6, p. 178. , IUPAP, (Moscow, USSR)Glauber, Mathiae, (1970) Nucl. Phys. B, 21, p. 135Hofstadter, Nuclear and Nucleon Scattering of High-Energy Electrons (1957) Annual Review of Nuclear Science, 7, p. 231Linsley, (1985) Proc. XIXth Intern. Cosmic ray Conf., 6, p. 1. , La Jolla, USA, and references therein for experimental dataHara, (1983) Phys. Rev. Lett., 50, p. 2058Hara, (1983) Proc. XVIIth Intern. Cosmic ray Conf., 11, p. 354. , Bangalore, IndiaBaltrusaitis, (1984) Phys. Rev. Lett., 52, p. 1380Bellandi, On the behaviour of inelasticity at very high energy (1991) Physics Letters B, 262, p. 102Brooke, Wolfendale, (1964) Proc. Phys. Soc., 83, p. 843Ashton, (1970) Acta Phys. Acad. Sci. Hung., 29, p. 25Vall, (1987) Sov. J. Nucl. Phys., 44, p. 806Wilk, (1991) Contrib. XXIInd Intern. Cosmic ray Conf., , Dublin, IrelandFowler, (1987) Phys. Rev. D, 35, p. 870Gaisser, (1989) Phys. Lett. B, 219, p. 375Gaisser, (1990) Proc. 21st Intern. Cosmic ray Conf., 8, p. 55. , AdelaideKopeliovich, (1989) Phys. Rev. D, 39, p. 769Azaryan, (1975) Sov. J. Nucl. Phys., 20, p. 213Slavatinskii, (1964) Sov. Phys. JETP, 19, p. 1452Basile, (1983) Nuovo Cimento, 73 A, p. 32

EEG spike source localization before and after surgery for temporal lobe epilepsy: a BOLD EEG-fMRI and independent component analysis study

Simultaneous measurements of EEG-functional magnetic resonance imaging (fMRI) combine the high temporal resolution of EEG with the distinctive spatial resolution of fMRI. The purpose of this EEG-fMRI study was to search for hemodynamic responses (blood oxygen level-dependent - BOLD responses) associated with interictal activity in a case of right mesial temporal lobe epilepsy before and after a successful selective amygdalohippocampectomy. Therefore, the study found the epileptogenic source by this noninvasive imaging technique and compared the results after removing the atrophied hippocampus. Additionally, the present study investigated the effectiveness of two different ways of localizing epileptiform spike sources, i.e., BOLD contrast and independent component analysis dipole model, by comparing their respective outcomes to the resected epileptogenic region. Our findings suggested a right hippocampus induction of the large interictal activity in the left hemisphere. Although almost a quarter of the dipoles were found near the right hippocampus region, dipole modeling resulted in a widespread distribution, making EEG analysis too weak to precisely determine by itself the source localization even by a sophisticated method of analysis such as independent component analysis. On the other hand, the combined EEG-fMRI technique made it possible to highlight the epileptogenic foci quite efficiently.58258

Diffractive Meson Production and the Quark-Pomeron Coupling

Diffractive meson production at HERA offers interesting possibilities to investigate diffractive processes and thus to learn something about the properties of the pomeron. The most succesful phenomenological description of the pomeron so far assumes it to couple like a $C = +1$ isoscalar photon to single quarks. This coupling leads, however, to problems for exclusive diffractive reactions. We propose a new phenomenological pomeron vertex, which leads to very good fits to the known data, but avoids the problems of the old vertex.Comment: 20 pages, latex with uuencoded postscript, revised versio

Charged Particle Multiplicity in Diffractive Deep Inelastic Scattering

The recent data from H1 Collaboration on hadron multiplicity in diffractive DIS has been studied in the framework of perturbative QCD as a function of invariant diffractive mass. The formulas obtained explain the observed excess of particle production in diffractive DIS relative to that in DIS and $e^+e^-$ annihilation. It is shown that the results are sensitive to the quark--gluon structure of the Pomeron. Namely, the data say in favour of a super-hard gluon distribution at the initial scale.Comment: 12 pages, 3 figures; to be published in Phys. Rev.

Charm Contribution to the Structure Function in Diffractive Deep Inelastic Scattering

The charm contribution to the structure functions of diffractive deep inelastic scattering is considered here within the context of the Ingelman-Schlein model. Numerical estimations of this contribution are made from parametrizations of the HERA data. Influence of the Pomeron flux factor is analized as well as the effect of the shape of the initial parton distribution employed in the calculations. The obtained results indicate that the charm contribution to diffractive deep inelastic process might be large enough to be measured in the HERA experiments.Comment: 16 pages, RevTeX, 6 figures, to be published in Physical Review

Systematics of Leading Particle Production

Using a QCD inspired model developed by our group for particle production, the Interacting Gluon Model (IGM), we have made a systematic analysis of all available data on leading particle spectra. These data include diffractive collisions and photoproduction at HERA. With a small number of parameters (essentially only the non-perturbative gluon-gluon cross section and the fraction of diffractive events) good agreement with data is found. We show that the difference between pion and proton leading spectra is due to their different gluon distributions. We predict a universality in the diffractive leading particle spectra in the large momentum region, which turns out to be independent of the incident energy and of the projectile type.Comment: 13 pages, Latex, 4 ps figures. To appear in Phys. Rev.