Generalized parton correlation functions for a spin-1/2 hadron

The fully unintegrated, off-diagonal quark-quark correlator for a spin-1/2 hadron is parameterized in terms of so-called generalized parton correlation functions. Such objects, in particular, can be considered as mother distributions of generalized parton distributions on the one hand and transverse momentum dependent parton distributions on the other. Therefore, our study provides new, model-independent insights into the recently proposed nontrivial relations between generalized and transverse momentum dependent parton distributions. We find that none of these relations can be promoted to a model-independent status. As a by-product we obtain the first complete classification of generalized parton distributions beyond leading twist. The present paper is a natural extension of our previous corresponding analysis for spin-0 hadrons.Comment: 41 pages, 3 figures; v2: added referenc

Diffractive upsilon production at the LHC

We compute the rate for diffractive upsilon meson production at the Tevatron and the LHC. The upsilon is produced diffractively via the subprocess gamma + p -> upsilon + p where the initial photon is radiated off an incoming proton (or antiproton). We consider the possibility to use low angle proton detectors to make a measurement of the gamma p cross-section and conclude that a measurement of the cross-section at a centre of mass energy in excess of 1 TeV is possible at the LHC. This is in the region where saturation effects are likely to reveal themselves.Comment: 14 page

Central exclusive production of longlived gluinos at the LHC

We examine the possibility of producing gluino pairs at the LHC via the exclusive reaction pp -> p+gluino+gluino+p in the case where the gluinos are long lived. Such long lived gluinos are possible if the scalar super-partners have large enough masses. We show that it may be possible to observe the gluinos via their conversion to R-hadron jets and measure their mass to better than 1% accuracy for masses below 350 GeV with 300/fb of data.Comment: 13 pages, 9 figures. Minor corrections to version

Forward Physics with Rapidity Gaps at the LHC

A rapidity gap program with great potential can be realized at the Large Hadron Collider, LHC, by adding a few simple forward shower counters (FSCs) along the beam line on both sides of the main central detectors, such as CMS. Measurements of single diffractive cross sections down to the lowest masses can be made with an efficient level-1 trigger. Exceptionally, the detectors also make feasible the study of Central Diffractive Excitation, and in particular the reaction g + g to g + g, in the color singlet channel, effectively using the LHC as a gluon-gluon collider.Comment: 15 pages, 11 figure

Forward Jet Production at the Large Hadron Collider

At the Large Hadron Collider (LHC) it will become possible for the first time to investigate experimentally the forward region in hadron-hadron collisions via high-pT processes. In the LHC forward kinematics QCD logarithmic corrections in the hard transverse momentum and in the large rapidity interval may both be quantitatively significant. We analyze the hadroproduction of forward jets in the framework of QCD high-energy factorization, which allows one to resum consistently both kinds of corrections to higher orders in QCD perturbation theory. We compute the short-distance matrix elements needed to evaluate the factorization formula at fully exclusive level. We discuss numerically dynamical features of multi-gluon emission at large angle encoded in the factorizing high-energy amplitudes

Detecting Higgs bosons in the bb decay channel using forward proton tagging at the LHC

A detailed study is presented of the search for Higgs bosons in the b-decay channel in the central exclusive production process at the LHC. We present results for proton tagging detectors at both 220m and 420m around ATLAS or CMS. We consider two benchmark scenarios; a Standard Model (SM) Higgs boson and the m_h^{max} scenario of the Minimal Supersymmetric Standard Model (MSSM). Detector acceptance, smearing and event trigger strategies are considered. We find that the SM Higgs will be challenging to observe in the b-jet channel without improvements to the currently proposed experimental configuration, but a neutral scalar MSSM Higgs Boson could be observable in the b-jet channel with a significance of 3 sigma or greater within three years of data taking at all luminosities between 2 x 10^{33} cm^{-2} s^{-1} and 10^{34} cm^{-2} s^{-1}, and at 5 sigma or greater after three years in certain scenarios.Comment: 35 pages, 34 figure