arXiv subjects
Publications and source records attributed to P. Marage.
Proceedings of the 13th International Conference on Elastic and Diffractive Scattering (Blois Workshop) - Moving Forward into the LHC Era
Recent results obtained at HERA on deeply virtual Compton scattering and exclusive vector meson production are reviewed, with the emphasis on the transition from soft to hard diffraction and on spin dynamics.
Talk given at the First Workshop on Forward Physics and Luminosity Determination at the LHC, Helsinki, Finland, November 2000. 12 pages, 9 figures
In the context of the tremendous progress achieved at HERA in diffraction and the need for a new level of statistical and systematic precision, the new very large acceptance forward spectrometer planned by H1 (VFPS) is presented and the physics issues are stressed.
A review is presented of numerous recent results, particularly those submitted to the EPS-HEP99 conference: very high Q^2 ep interactions and direct tests of the Standard Model, new measurements of the structure of the proton (including high x parton distributions and tests of QCD involving the gluon distribution), low x physics (tests of the BFKL evolution), diffraction in DIS at HERA, hard diffraction at the Tevatron and exclusive production of vector particles at HERA. The focus is on hard QCD features.
A review is presented of diffractive vector meson production at HERA, with stress on the investigation of ``hard'' features and comparisons with theoretical predictions based on perturbative QCD approaches.
Diffraction studies at HERA are introduced, with reference to other communications to this Conference. Motivations and specific features of the experimental approaches are stressed.
The production of hadrons in charged-current (anti)neutrino interactions is studied with the bubble chamber BEBC exposed ot the CERN (anti)neutrino wide-band beam. Fast-hadron production in a neon target is found to be attennuated as compared to that in a hydrogen target. This feature is discussed within the theoretical models based on the idea of a hadron formation length. The experimental results favour the `constituent' over the `yo-yo' length concept, and suggest a quark cross-section in the order of 3mb.
The general framework of diffractive deep inelastic scattering is introduced and reports given in the session on diffractive interactions at the International Workshop on Deep-Inelastic Scattering and Related Phenomena, Rome, April 1996, are presented.
It is shown that a significant measurement of the longitudinal structure function $F_L(x,Q^2)$ can be performed at HERA, for $Q^2 = 2 GeV^2$ and $Q^2 = 5 GeV^2$ and for x around $10^{-4}$, using radiative events with hard photon emission collinear to the incident lepton beam, under the present running conditions and with an integrated luminosity of 10 $pb^{-1}$. The influence of experimental conditions is discussed.