logo
    Photoproduction of mesons at HERA
    T. AhmedS. AïdV. A. AndreevBernard AndrieuR.D. AppuhnM. ArpagausA. BabaevJ. BaehrJ. BánP. BaranovE. BarreletW. BartelM. BarthU. BasslerH. P. BeckH.‐J. BehrendA. BelousovCh. BergerH. BergsteinG. BernardiR. BernetG. Bertrand-CoremansM. BesançonR. BeyerP. BiddulphJ.C. BizotV. BlodelK. BorrasF. BotterweckV. BorrdryA. BraemerF. BrasseW. BraunschweigV. BrissonD. BrunckoC. R. BruneR. BuchholzL. BüngenerJ. BürgerF.W. BüsserA. BuniatianS. BürkeG. BuschhornA.J. CampbellT. CarliF. CharlesD. ClarkeA.B. CleggM. ColomboJ.G. ContrerasJ. A. CoughlanA. CourauC. CouturesG. CozzikaL. CriegeeD. CussansJ. CvachS. Dagoret-CampagneJ.B. DaintonM. DanilovW.D. DauK. DaumM. DavidE. DeffurB. DelcourtL. Del BuonoA. De RoeckE. A. De WolfP. Di NezzaC. DollfusJ.D. DowellH.B. DreisJ. DubocD. DüllmannO. DüngerH.H. DuhmJ. EbertT.R. EbertG. EckerlinV. EfremenkoS. EgliH. EhrlichmannS. EichenbergerR. EichlerF. EiseleE. EisenhandlerR.J. EllisonE. ElsenM. ErdmannW. ErdmannE. EvrardL. FavartA. FedotovD. FeekenR. FelstJ. FeltesseJ. FerenceiF. FerrarottoK. FlammM. FleischerM. FlieserG. FlüggeA. FomenkoB. FominykhM. ForbushJ. FormánekJ.M. FosterG. FrankeE. FretwurstE. GabathulerK. GabathulerK. GamerdingerJ. GarveyJ. GaylerM. GebauerA. GellrichH. GenzelR. GerhardsU. GoerlachL. GoerlichN. GogitidzeM. GoldbergD. GoldnerB. González-PineiroA.M. GoodallI. GorelovP. GoritchevC. GrabH. GrässlerR. GrässlerT. GreenshawG. GrindhammerA. GruberC. GrubberJ. HaackD. HaidtL. HajdukO. HamonMatías Rolf HampelE.M. HanlonM. HapkeW.J. HaynesJ. HeatheringtonV. HedbergG. HeinzelmannR. C. W. HendersonH. HenschelR. HermaI. HerynekM.F. HessW. HildesheimP. HillK. H. HillerC.D. HiltonJ. HladkýK.C. HoegerM. HöppnerR. HorisbergerPh. HuetH. HufnagelM. IbbotsonH. ItterbeckM. A. JabiolA. JachołkowskaC. JacobssonM. JaffréJ. JanothT. JansenL. JönssonK. JohannsenD.P. JohnsonL. JöhnsonH. JungP.I.P. KalmusD. KantR. KaschowitzP. KasselmannU. KathageH.H. KaufmannS. KazarianI. R. KenyonS. KermicheC. KeukerC. KieslingM. KleinC. KleinwortG. KniesW. KoT. KöhlerH. KolanoskiF. KoleS.D. KolyaV. KorbelM. KornP. KostkaS.K. KotelnikovM. W. KrasnyH. KrehbielD. KrückerU. KrügerU. Krüner-MarquisJ.P. KubenkaH. KüsterT. KurlenT. KurčaJ. KurzhöferB. KuznikD. LacourF. LamarcheR. LanderM. P. J. LandonW. LangeP. LaniusJ. F. LaporteA. LebedevC. LeverenzS. LevonianCh. LeyA. LindnerG. LindströmF. LinselJ. LipińskiB. ListP. LochH. LohmanderG.C. LopezD. LükeN. MagnussenE. MalinovskiS. ManiR. MaračekP. MarageJ. MarksR. MarshallJ. MartensR. MartinH.‐U. MartynJ. MartyniakS. MassonT. MavroidisS. J. MaxfieldS. J. McMahonA. MehtaK. MeierD. MercerT. MerzC. A. MeyerH. MeyerJ. MeyerS. MikockiD. A. MilsteadF. MoreauJ.V. MorrisG. MüllerK. MüllerП. МурінR. NahnhauerB. NaroskaT. NaumannP. R. NewmanD. NewtonD. NeyretH.K. NguyenF. NiebergallC. NiebuhrR. NisiusG. NowakG.W. NoyesM. Nyberg-WertherH. OberlackU. ObrockJ.E. OlssonE. PanaroA. PanitchC. PascaudG. D. PatelE. PeppelE. PérezJ. P. PhillipsChristian PichlerD. PitzlG. PopeS. PrellR. ProsiG. RädelF. RaupachP. ReimerS. ReinshagenP. RibaricsV. RiechJ. RiedlbergerS. RießM. RietzS. RobertsonR. RobmannH.E. RoloffR. RoosenK. RosenbauerA. RostovtsevF. RouseC. RoyonK. RüterS. V. RusakovK. RybickiR. RyłkoN. SahlmannE. SánchezD. P. C. SankeyM. SavitskyP. SchachtS. SchiekP. SchleperW. von SchlippeCarl R. SchmidtD. SchmidtG. SchmidtA. SchöningV. SchröderE. SchuhmannB. SchwabA. SchwindU. SeehausenF. SefkowM. SeidelRaivo SellA. SemenovV. ShekelyanI. SheviakovH. ShooshtariL.N. ShtarkovG. SiegmonU. SiewertY. SiroisI. O. SkillicornP. SmirnovJ. R. SmithY. SolovievH. SpitzerR. StarostaM. SteenbockP. SteffenR. SteinbergB. StellaK. StephensJ. StierJ. StieweU. StößleinJ. StrachotaU. StraumannW. StruczinskiJ.P. SuttonS. TapproggeR. E. TaylorV. TchernyshovCh. ThiebauxG. ThompsonI. TichomirovP. TruölJ. TurnauJ. TutasP. UelkesA. UsikŠ. ValkárA. ValkárováC. ValléeP. Van EschP. Van MechelenA. VartapetianY. VazdikM. VeckoP. VerrecchiaG. VilletK. WackerA. WagenerM. WagenerI.W. WalkerA. WaltherG. WeberM. WeberD. WegenerA. WegnerH.P. WellischL.R. WestS. WillardM. WindeG.G. WinterA.E. WrightE. WünschN. WulffT.P. YiouJ. ŽáčekD. ZarbockZ. ZhangM. ZimmerW. ZimmermannF. ZomerΚ. Zuber
    44
    Citation
    26
    Reference
    10
    Related Paper
    Citation Trend
    The recent ${F}_{2}$ data can be described using the DGLAP evolution equations with an appropriate choice of input distributions and the choice of the starting scale for the ${Q}^{2}$ evolution. We demonstrate in this paper that we cannot conclude that there are no significant shadowing corrections in the DESY HERA kinematic region using ${F}_{2}$ data only. In this paper we calculate the shadowing corrections to the longitudinal structure function ${F}_{L}{(x,Q}^{2})$ and to the charm component of the proton structure function ${F}_{2}^{c}{(x,Q}^{2})$ in the HERA kinematic region using an eikonal approach. We demonstrate that the shadowing corrections to these observables are very large and that charm production is strongly modified at small $x.$ Our results agree with the few recent H1 data.
    DESY
    DGLAP
    Charm (quantum number)
    Structure function
    Citations (15)
    DESY
    ZEUS (particle detector)
    Neutral current
    Citations (2)
    At HERA, the electron-proton collider at DESY, Hamburg, the large flux of almost on-shell photons accompanying the lepton beam is being used to shed new light on the structure of the photon. Recent results are reviewed and discussed, with emphasis on those aspects of the photon's nature which should be understandable using perturbative QCD.
    DESY
    ZEUS (particle detector)
    Photon flux
    Citations (0)
    At HERA, the electron-proton collider at DESY, Hamburg, the large flux of almost on-shell photons accompanying the lepton beam is being used to shed new light on the structure of the photon. Recent results are reviewed and discussed, with emphasis on those aspects of the photon's nature which should be understandable using perturbative QCD.
    DESY
    ZEUS (particle detector)
    Photon flux
    The QCD evolution of both unpolarized and polarized generalized parton distributions (GPDs) to next-to-leading order (NLO) accuracy is presented, in both the DGLAP and ERBL regions, for two appropriately symmetrized input distributions based on conventional parton density functions. To illustrate the relative size of the NLO corrections a comparison is made with leading order evolution of the same distributions. For the first time, NLO results are given for both small and large values of the skewedness parameter, $\ensuremath{\zeta}{=x}_{\mathrm{bj}},$ i.e., for all of the kinematic range relevant to DESY HERA and HERMES.
    DGLAP
    DESY
    Citations (28)
    The next-to-leading order (NLO) QCD calculation for the isolated photon and isolated photon plus jet photoproduction at the ep collider DESY HERA is presented. The predictions for the isolated photon with no restrictions imposed on the jet are compared with the previous ones obtained in the small cone approximation, and the differences are found to be below 2%. The theoretical uncertainties in the cross section of the photoproduction of the photon plus jet are discussed. A short comparison with the new preliminary H1 data and with the NLO predictions of Fontannaz et al. is also presented.
    DESY
    We demonstrate that perturbative QCD allows one to calculate the absolute cross section of diffractive exclusive production of photons at large ${Q}^{2}$ at DESY HERA, while the aligned jet model allows one to estimate the cross section for intermediate ${Q}^{2}\ensuremath{\sim}2 {\mathrm{GeV}}^{2}.$ Furthermore, we find that the imaginary part of the amplitude for the production of real photons is larger than the imaginary part of the corresponding DIS amplitude by about a factor of $2,$ leading to the prediction of a significant counting rate for the current generation of experiments at HERA. We also find a large azimuthal angle asymmetry in $\mathrm{ep}$ scattering for HERA kinematics which allows one to directly measure the real part of the DVCS amplitude and hence the nondiagonal parton distributions.
    DESY
    Perturbative QCD
    Citations (60)