Related papers: Inclusive Two--Photon Reactions at TRISTAN
We compute cross sections for events where two pairs of partons scatter off each other in the same $\gamma\gamma$ reaction, giving rise to at least 3 high--{\mbox{$p_T^{}$}} jets. Unlike in {\mbox{$p \bar p$}}\ collisions we find the signal…
At HERA, the large flux of almost real photons accompanying the electron beam leads to the copious photoproduction of jets. Regions of small momentum fractions $x$ of the incoming particles are explored, where the density of partons is…
The cross--section for two--photon events with (at least) two independent partonic scatters is estimated, for LEP energies as well as a 500 GeV ``photon collider". This results in events with (at least) four central (mini--)jets. Such…
We have calculated inclusive two-jet production in photon-photon collisions superimposing direct, single-resolved and double-resolved cross sections for center-of-mass energies of TRISTAN and LEP1.5. All three contributions are calculated…
We have calculated inclusive one-- and two--jet production in photon--photon collisions in next--to--leading order superimposing direct, single resolved and double resolved cross sections. The results are compared with recent experimental…
Jets observed in hadron-hadron scattering contain a contribution from the underlying event that is produced by spectator interactions taking place incoherently with the major parton-parton collision, due to the extended composite structure…
Multiparton interactions are introduced in order to explain a wide range of phenomena in p-p collisions. We present the most recent CMS measurements sensitive to multiparton interactions and hard double parton scattering at 7 TeV. In…
We study the multiple scattering effects on inclusive particle production in p+A and $\gamma$+A collisions. Specifically, we concentrate on the region where the parton momentum fraction in the nucleus $x\sim {\cal O}(1)$ and incoherent…
We present a short overview over the different contributions to high energy photon photon scattering and explore the possibilities of tuning the sizes of the scattered objects by changing the virtuality of the photons. We compare the…
Exclusive two-photon reactions such as Compton scattering at large angles, deeply virtual Compton scattering, and hadron production in photon-photon collisions provide important tests of QCD at the amplitude level, particularly as measures…
Presented are recent results of two-photon interactions. Topics inlcude photon structure functions, inclusive hadron production, differential cross sections derived from tagged 2-photon fusion events and results in exclusive hadron…
Two-photon events at the LHC are characterized by the protons scattered at very small angles and the particles centrally produced via the photon-photon fusion. To select these events from the huge samples of generic pp interactions a…
A measurement of inclusive four-jet production in proton-proton collisions at a center-of-mass energy of 13 TeV is presented. The transverse momenta of jets within $\lvert\eta\rvert$ $\lt$ 4.7 reach down to 35, 30, 25, and 20 GeV for the…
Double parton scattering events are directly sensitive to the correlations between two partons inside a proton and can answer fundamental questions on the connections between the proton constituents. In this chapter, the different types of…
In this contribution we present the main results of the investigation about double parton scattering (DPS) in quasi-real photon-proton interactions. We show the first evaluation of the DPS cross-section at leading-order for the four-jet…
The concept of multiple partonic interactions in hadronic events is vital for the understanding of both minimum-bias and underlying-event physics. The area is rather little studied, however, and current models offer a far from complete…
In proton-proton collisions there is a smooth transition between the regime of double parton scattering, initiated by two pairs of partons at a large relative distance, and the regime where a single parton splits into a parton pair in one…
This paper summarizes the Multiple Parton Interactions studies in CMS, focusing on the already performed low pT QCD measurements up to highest centre of mass energies of 7 TeV and discussing the plans for the direct measurement of the…
The joint study of Double Parton Scatterings, in high energy proton-proton and proton-nucleus collisions, can provide a lot of information on multi-parton correlations. The multi-parton structure is in fact probed in a different way by DPS,…
The high energy photoproduction of jets is being observed at the ep collider, HERA. It may be that the HERA centre-of-mass energy is sufficiently large that the production of more than one pair of jets per ep collision becomes possible,…