相关论文: Open charm production in DIS at HERA
The data on the diffractive deep inelastic scattering (DDIS) at HERA exhibit a strong excess, up to about 100%, above the twist-two NLO DGLAP description at low $Q^2$ and at large energy. I show, that complementing the DGLAP fit by twist 4…
Differential photoproduction cross sections are measured for events containing D* mesons. The data were taken with the H1 detector at the ep collider HERA and correspond to an integrated luminosity of 51.1 pb-1. The kinematic region covers…
Measurements of vector mesons at HERA allow a detailed study of diffractive and non-diffractive production mechanisms, fragmentation and decay branching ratios. Results are presented on hadronic resonance measurements. In addition, the…
We analyse recent data on the production of forward neutrons in deep inelastic scattering at HERA in the framework of a perturbative QCD description for semi-inclusive processes, which includes fracture functions.
Following recent predictions that the geometric scaling properties of deep inelastic scattering data in inclusive gamma*-p collisions are expected also in exclusive diffractive processes, we investigate the diffractive production of vector…
Several methods to extract the strong coupling constant $\alpha_s$ by means of highly energetic jets in Deep-Inelastic Scattering are presented. The results from the various methods agree with one another and with the world average. The…
A brief survey is given of recent HERA results in jet production and prompt photon production, together with the evaluation of the QCD coupling constant alpha_s.
We present a formulation which allows heavy quark (c, b, ...) mass effects to be explicitly incorporated in both the coefficient functions and the splitting functions in the parton evolution equations. We obtain a consistent procedure for…
We study inclusive $J/\psi$ photoproduction at NLO at large $P_T$ at HERA and the EIC. Our computation includes NLO QCD leading-$P_T$ corrections, QED contributions via an off-shell photon as well as those from $J/\psi$+charm channels. For…
Recent measurement of inclusive processes and hadronic final states in diffractive deep-inelastic scattering at HERA are used to investigate the QCD factorisation properties and study partonic structure of colour singlet exchange. Resolved…
We report on the measurement of D meson production from the analysis of their hadronic ($D^0\to K\pi$) and semileptonic ($D\to \mu+X$, $D\to e+X$) decays in $\sqrt{s_{NN}}$=200 GeV Au+Au collisions. The transverse momentum ($p_T$) spectra…
We present recent experimental data from the H1 and ZEUS Collaborations at HERA for diffractive dijet production in deep-inelastic scattering (DIS) and photoproduction and compare them with next-to-leading order (NLO) QCD predictions using…
We determine the charm-quark mass mc(mc) in the MS-bar scheme using measurements of charm production in deep-inelastic ep scattering at HERA in the kinematic range of photon virtuality from 5 to 1000 GeV squared and Bjorken scaling variable…
We discuss two topics in the production of heavy quarks in deep-inelastic scattering: the next-to-leading order Monte-Carlo HVQDIS and the next-to-leading logarithmic resummation of soft gluon effects, including estimates of…
This talk is a rather sceptical review of our knowledge and understanding of deep inelastic scattering at low x (high energy). We show that the well known success of the DGLAP evolution equations in describing of experimental HERA data…
Dijet cross sections in neutral current deep inelastic ep scattering have been measured in the range $10 < \Q2 < 10^4$ GeV$^2$ with the ZEUS detector at HERA using an integrated luminosity of 38.4 pb$^{-1}$. The cross sections, measured in…
We calculate the cross section for q(\bar q)g-production in diffractive DIS with finite fermion masses and zero momentum transfer. The calculation is done in the leading log(1/x_p) approximation and is valid for the region of high…
The results of measurement of beauty quark production at HERA performed by the H1 and ZEUS collaborations are presented. Total cross sections and the differential cross sections have been measured in both the photoproduction and the deep…
In this article, recent measurements of diffraction in deep inelastic scattering are presented along with QCD fits to extract the partonic structure of the exchange. These so-called diffractive parton density functions can then be used in…
We present a brief status report of our broad and systematic study of QCD-instantons at HERA.