Prompt J/ψ plus photon associated electroproduction at DESY HERA
نویسنده
چکیده
We study the production of a prompt J/ψ meson in association with a prompt photon in ep deep-inelastic scattering within the factorisation formalism of nonrelativistic quantum chromodynamics (NRQCD) and demonstrate that this process provides a clean probe of the colour-octet mechanism at DESY HERA. Our analysis is based on an updated set of non-perturbative NRQCD matrix elements obtained through a joint fit to data on charmonium inclusive hadroproduction from runs I and II at the Fermilab Tevatron. PACS: 12.38.-t, 12.38.Bx, 13.85.Fb, 14.40.Gx
منابع مشابه
Color-Octet Contributions to J/ψ Photoproduction via Fragmentation at HERA
We study J/ψ photoproduction via fragmentation at next-to-leading order in the QCD-improved parton model, using the nonrelativistic factorization formalism proposed by Bodwin, Braaten, and Lepage. We consider direct and resolved photoproduction of prompt J/ψ mesons and χcJ mesons radiatively decaying to J/ψ+ γ, taking into account the formation of both color-singlet and color-octet cc̄ states. A...
متن کاملPrompt Photon Plus Jet Photoproduction at HERA at Next-to-Leading Order in QCD
The cross section for photoproduction of an isolated prompt photon in association with a jet is studied in Next-to-Leading Order. The kinematics are those appropriate for the DESY ep collider HERA. The effects on the cross section of various experimental cuts including isolation cuts on the photon is examined. Comparisons with the ZEUS preliminary data using two parametrizations of the photon s...
متن کاملCharmonium Production via Fragmentation at DESY HERA
The cross section for the photoproduction of large-pT J/ψ mesons at HERA is calculated at next-to-leading order, adopting a perturbative approach to describe the fragmentation of charm quarks and gluons into J/ψ mesons. We treat the charm quark according to the massless factorization scheme, where it is assumed to be one of the active flavours inside the proton and the resolved photon. We prese...
متن کاملInelastic Photo-and Electroproduction of Charmonium
Measurements of inelastic production of charmonium with the ZEUS detector at HERA are presented. J/ψ and ψ′ mesons have been identified using the decay channel ψ → μμ. The data, corresponding to an integrated luminosity of 38 pb in photoproduction and 73.3 pb in electroproduction, are confronted to theoretical predictions.
متن کاملJ/ψ plus prompt-photon associated production in two-photon collisions at next-to-leading order
We calculate the cross section of J/ψ plus prompt-photon inclusive production in γγ collisions at next-to-leading order within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD) focusing on direct photoproduction. Apart from direct J/ψ production, we also include the feed-down from directlyproduced χcJ and ψ ′ mesons. We discuss the analytical calculation, in particul...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2006