arXiv subjects
Publications and source records attributed to Konstantin Goulianos.
Predictions of the gap-probability renormalization model for single and double diffraction dissociation cross sections in proton-proton collisions at the LHC are presented and compared with recent CMS measurements.
We present a CDF measurement of diffractive dijet production in $\bar{p}p$ collisions at 1.96 TeV at the Fermilab Tevatron Collider using data from an integrated luminosity of $\approx 310$ pb$^{-1}$ collected by triggering on a high transverse momentum jet in coincidence with a recoil antiproton detected in a roman pot spectrometer. We report final results for 4-momentum transfer squared $t>-4$ GeV$^2$, antiproton-momentum-loss fraction within 0.03-0.09, Bjorken-x of the interacting parton in the antiproton in the range 0.001-0.1, and jet transverse energies from 10 to 100 GeV.
We present measurements of soft single- and double-diffractive cross sections, as well as of forward rapidity gap cross sections at 7 TeV at the LHC, and compare the results to other measurements and to theoretical predictions implemented in various Monte Carlo simulations.
Results from the large hadron collider (LHC) show that no available Monte Carlo simulation incorporates our pre-LHC knowledge of soft and hard diffraction in a way that could be reliably extrapolated to LHC energies. As a simulation is needed to establish triggers, perform underlying event corrections and calculate acceptances, the lack of a robust simulation affects all measurements at the LHC. Particularly affected are the measurements of processes with large diffractive rapidity gaps, which constitute about one quarter of the inelastic cross section. In this paper, a previously described phenomenological model based on a saturation effect observed in single diffraction dissociation in pre-LHC data, validated by its successful application to several diffractive processes, is used to predict the total and total-inelastic proton-proton cross sections at the LHC. The prediction for the total-inelastic cross section at a center of mass collision energy of 7 TeV is compared with recent results from ATLAS and CMS.
We present final results by the CDF II collaboration on diffractive W and Z production, report on the status of ongoing analyses on diffractive dijet production and on rapidity gaps between jets, and briefly summarize results obtained on exclusive production pointing to their relevance to calibrating theoretical models used to predict exclusive Higgs-boson production at the LHC.
We discuss a phenomenological model that describes results on diffractive pp and pbar-p cross sections and event final states up to the Fermilab Tevatron collider energy of 1.96 TeV and use it to make predictions for Large Hadron Collider (LHC) collision energies up to 14 TeV and asymptotically as the pp collision energy goes to infinity. The model is anchored in a saturation effect observed in single diffraction dissociation that explains quantitatively the factorization breaking observed in soft and hard pp and pbar-p diffractive processes and in diffractive photoproduction and low Q-square deep inelastic scattering.
The ratio of intercept to slope of the Pomeron trajectory is derived in a phenomenological model based on a QCD approach to diffraction.
Results on diffraction from the Fermilab Tevatron collider obtained by the CDF II Collaboration using data from proton-antiproton collisions at a c.m.s. energy of 1.96 TeV are reviewed and compared with theoretical expectations. Implications for predictions of exclusive Higgs boson production rates at the Large Hadron Collider are discussed.
The diffractive program of the CDF Collaboration at the Fermilab Tevatron p-pbar collider is reviewed with emphasis on recent results from Run II at a c.m.s. energy of 1.96 TeV. Results are presented on the x-Bjorken and Q^2 dependence of the diffractive structure function obtained from di-jet production, on the slope parameter of the t-distribution of diffractive events as a function of Q^2 in the range 1 GeV^2<Q^2<10^4 GeV^2, and on cross sections for exclusive di-jet, e+e-, and di-photon production. The exclusive di-jet and di-photon production rates are used to check theoretical estimates of exclusive Higgs boson production at the Large Hadron Collider. Other data on soft and hard diffraction from p-ppbar collisions, and also data from diffractive deep inelastic scattering are presented and interpreted in the RENORM phenomenological model, in which cross sections are obtained from the underlying inclusive parton distribution function of the nucleon and QCD color factors.
We report recently published results on central exclusive production of di-jets and di-photons, and exclusive QED production of e+e- pairs. In addition, we discuss preliminary results on exclusive photoproduction of charmonium and bottomonium, exclusive QED production of mu+mu- pairs, and single diffractive W/Z production. All the presented results were extracted from data collected by the CDF II detector from proton-antiproton collisions at a c.m.s. energy of 1.96 TeV. The implications of these results for the Large Hadron Collider are briefly examined.
Results from the Fermilab Tevatron pbar-p collider on diffractive and total cross sections are reviewed with emphasis on physics significance and properties pointing to expectations at the LHC.
The diffractive program of the CDF Collaboration at the Fermilab Tevatron pbar-p Collider is reviewed with emphasis on recent results from Run-II and future prospects.
The large rapidity interval available at the Large Hadron Collider (LHC) offers an arena in which the QCD aspects of diffraction may be explored in an environment free of gap survival complications using events with multiple rapidity gaps.
Experimental results on hadronic soft and hard diffractive processes are reviewed with emphasis on aspects of the data that point to the underlying QCD mechanism for diffraction. Diffractive differential cross sections are shown to be factorized into two terms, one representing the total cross section at the reduced energy, corresponding to the rapidity region(s) in which there is particle production, and another interpreted as the probability of formation of the rapidity gap(s) characterizing diffraction. By (re)normalizing the term of gap formation probability to unity, cross sections for single, central, and multiple rapidity gap soft diffraction, as well as structure functions for hard diffraction processes, are obtained from the underlying inclusive parton distribution functions. A unified partonic picture emerges, in which diffraction appears to be mediated by the exchange of low-x partons subject to color constraints.
Results on soft and hard diffraction obtained by the CDF Collaboration at the Fermilab Tevatron proton-antiproton Collider are reviewed with emphasis on aspects of the data that point to the underlying QCD mechanism for diffraction. The results are interpreted in terms of a phenomenological approach in which diffraction is due to an exchange of low-x partons subject to color constraints.
We review the results of measurements on hard diffractive processes performed by the CDF Collaboration and report preliminary CDF results on two soft diffractive processes with a leading antiproton and a rapidity gap in addition to that associated with the antiproton. All results have been obtained from data collected in Run I of the Fermilab Tevatron $\bar pp$ collider.
We review the results of measurements on soft and hard diffractive processes performed by the CDF Collaboration at the Fermilab Tevatron pbar-p collider in run I and place them in perspective by internal comparisons, as well as by comparisons with results obtained at the HERA e-p collider and with theoretical expectations.
Results on soft and hard diffraction are briefly reviewed and placed in a QCD perspective using a parton model approach. Issues addressed include factorization, scaling properties, universality of rapidity gap formation, and unitarity. Predictions for differential cross sections of processes with multiple rapidity gaps are presented with examples for the Tevatron and the Large Hadron Collider. This paper is an expanded version of a paper delivered at SNOWMASS-2001 (arXiv:hep-ph/0110240).