Related papers: pp Interaction in Extended Air Showers
A measurement of the inclusive deep-inelastic neutral current e+p scattering cross section is reported in the region of four-momentum transfer squared, 12<=Q^2<=150 GeV^2, and Bjorken x, 2x10^-4<=x<=0.1. The results are based on data…
Recent measurements of the inelastic and total proton-proton cross section at the LHC, and at cosmic ray energies by the Auger experiment, have quantitatively confirmed fits to lower energy data constrained by the assumption that the proton…
The pseudorapidity measurements at LHC, although in the central region only, allows to perform preliminary tests of the multiparticle production extrapolation formula inspired by the recent cosmic ray data analysis. Feynman scaling…
Three main statements are advocated in this talk: 1. Protons become more active at the periphery with increase of their collision energy as follows from comparison of ISR and LHC data. 2. The geometric scaling is violated even in the…
The differential cross-sections are calculated for proton-proton and proton-antiproton elastic scattering using the phenomenological model based on the analytic parameterizations for global scattering parameters (total cross-section and…
Large scale airshower simulations around the GZK cutoff are performed. An extensive analysis of the behaviour of the various subcomponents of the cascade is presented. We focus our investigation both on the study of total and partial…
A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom…
We show that the data for the total cross section and for the real part of the elastic amplitude indicate the presence of a hard pomeron in pi p and Kp elastic scattering at t=0, compatible with that observed in deep inelastic scattering.…
Differential cross sections for jet photoproduction in the reaction ep --> e jet X have been measured with the ZEUS detector at HERA using 82.2 pb^-1 of integrated luminosity. Inclusive jet cross sections are presented as a function of the…
Jets, clusters of collimated particles produced in high energy proton-proton ($pp$) collisions, are an excellent tool to study the internal structure of the proton. According to perturbative QCD (pQCD) calculations, for center-of-mass…
Inclusive jet and multijet cross sections measured in ep collisions in different kinematic regions by the H1 and ZEUS experiments are shown. The measurements are used to extract the strong coupling alpha_s as a function of the scale and at…
Based on the extended optical model approach in which the polarization potential is decomposed into direct reaction (DR) and fusion parts, simultaneous $\chi^{2}$ analyses are performed for elastic scattering, DR, and fusion cross section…
Recent ZEUS measurements of inclusive-jet and dijet cross sections in neutral current deep inelastic ep scattering at HERA are presented. The data correspond to more than a two-fold increase in statistics compared to previous studies. The…
We show that combining the published Pierre Auger Observatory measurements of the longitudinal_and_ lateral properties of UHE atmospheric showers, points to an unforeseen change in the nature of particle interactions at ultrahigh energy. A…
The Pierre Auger Observatory has been designed to investigate the most energetic particles known, the ultra high energy cosmic rays. The observatory, covering an area of 3000 km^2, combines two different detection techniques to study the…
We study the consequences of high-energy collider data on the best fits to total, elastic, and inelastic cross sections for $pp$ and $p\bar{p}$ scattering using two very distinct unitarisation schemes: the eikonal and the $U$-matrix.…
The data on p$\mathrm{\bar p}$ elastic scattering at 1.8 and 1.96 TeV are analysed in terms of real and imaginary amplitudes, in a treatment with high accuracy, covering the whole t-range and satisfying the expectation of dispersion…
The hardness of the energy spectrum of neutral pions produced in proton-air interactions at ultra-high energies, above $10^{18}$ eV, is constrained by the steepness of the shower-to-shower distribution of the number of muons in…
Following prior analysis for measured pp elastic differential cross section, the impact parameter representation in terms of profile functions is calculated from two different parameterizations on single diffractive dissociation data. The…
We describe a novel technique for comparing total cross sections for the reactions pp --> pp pi(0), pp --> pp eta, and pp --> pp eta' close to threshold. The initial and final state proton-proton interactions are factored out of the total…