Related papers: Direct photon production at HERA, the Tevatron and…
Production of prompt isolated photons at hadron colliders provides a probe of perturbative QCD and can be used to study the gluon density function of the proton. The ATLAS collaboration has performed precise measurements of the inclusive…
Two recent results in ep physics using the ZEUS detector at HERA are discussed: a measurement of the prompt photon production cross section in photoproduction, and the first observation of Deeply Virtual Compton Scattering in DIS.
In the first part of this paper we assess the possibility of observing the gluon distribution in a real photon by measuring the photoproduction cross section of large-pt photons. In the second part we calculate the virtual photoproduction…
Recent results from HERA and TevaTron on precision tests of QCD with jets, W and Z bosons and photons associated with jets and heavy flavours are presented. The measurements were used to probe QCD at the highest energies, to provide…
Direct photons are an important tool for the detection of the quark-gluon plasma in ultra-relativistic nucleus-nucleus collisions. Direct-photon measurements were made in Pb+Pb collisions at sqrt{s_NN}=17.2 GeV and in Au+Au collisions at…
Using updated gluon distributions from global fits to data, we investigate the sensitivity of direct photoproduction of heavy quarks and exclusive production of vector mesons to varying strength of gluon modifications. Implications of using…
We attempt, in this paper, to deal with the direct photon production phenomena in $p+p$, $d+Au$ and $Au+Au$ collisions at RHIC energy, $\sqrt{s_{NN}}$ = 200 GeV and in $Pb+Pb$-collisions at LHC energy, $\sqrt{s_{NN}}$ = 2.76 TeV on the…
The diffractive photoproduction of rho mesons, e p \to e rho Y, with large momentum transfer squared at the proton vertex, |t|, is studied with the H1 detector at HERA using an integrated luminosity of 20.1 pb^{-1}. The photon-proton centre…
The physics scope of a possible future experiment utilizing an internal polarized nucleon target in the HERA proton beam is discussed. By measuring single spin asymmetries in inclusive particle production at 820~GeV beam energy the…
We investigate inclusive prompt photon and semi-inclusive prompt photon-hadron production in high energy proton-nucleus collisions using the Color Glass Condensate (CGC) formalism which incorporates non-linear dynamics of gluon saturation…
The measurement of the polarized gluon distribution function $\Delta g(x)$ from photon gluon fusion processes in electron proton deep inelastic scattering producing two jets has been investigated. The study is based on the MEPJET simulation…
Measurements of heavy quark production at a possible future $ep$ facility, THERA, would provide valuable information on the structure of the photon. QCD cross-section predictions are made at LO for both charm and beauty production and their…
A review is presented on studies of high $E_T$ jet production and production of photon, $W$ and $Z$ associated with jets from the HERA and Tevatron experiments. Such studies have been used to examine the Standard Model (SM) in the area of…
We reconsider the inclusive production of isolated prompt photons in $pp$ collisions at the LHC energies in the framework of $k_T$-factorization approach. Our analysis is based on the ${\cal O}(\alpha \alpha_s)$ off-shell (depending on the…
We present all relevant details of our calculation of the complete next-to-leading order (O(alpha_s^2 alpha)) QCD corrections to heavy flavor photoproduction with longitudinally polarized point-like photons and hadrons. In particular we…
A leading order determination of the gluon density in the proton has been performed in the fractional momentum range $1.9 \cdot 10^{-3} < x_{g/p} < 0.18$ by measuring multi-jet events from boson-gluon fusion in deep-inelastic scattering…
We present results of a global tuning of general purpose Monte Carlo models to published measurements of photon-proton -> jets at HERA and photon-photon -> jets at LEP and TRISTAN. The principle free parameters in the tuning are the…
In the framework of the kt-factorization approach, we study the production of prompt photons and electroweak gauge bosons in high energy proton-(anti)proton collisions at modern colliders. Our consideration is based on the amplitude for the…
Results from the PHENIX experiment at RHIC on direct photon production in p+p, d+Au, and Au+Au collisions at sqrt(s_NN) = 200 GeV are presented. In p+p collisions, direct photon production at high p_T behaves as expected from perturbative…
Recent structure function results from H1 and ZEUS are presented. The data have been recorded in e+p and e-p collisions for both Neutral Current and Charged Current reactions, covering a wide kinematic range of squared four-momentum…