arXiv subjects
Publications and source records attributed to Joerg Gayler.
A summary of experimental contributions to HSQCD 2005 is given. This includes results from the four HERA experiments H1, ZEUS, HERMES and HERA-B, as well as results from the Tevatron (D0), the CERN hyperon beam (WA98), from RHIC (PHENIX), and IHEP (SVD). I present a short survey of the points appearing most relevant to me.
Recent inclusive neutral current and charged current DIS data from HERA are discussed in context of pQCD and parton density functions.
An introduction is given to recent results in prompt photon production in different reactions.
Data are presented on the production of jets and pi^0 mesons at low Bjorken x in a kinematic region where standard DGLAP evolution in Q^2 gives little phase space for high p_t particle and jet production. The data are compared with various QCD models based on different treatments of parton emissions at small x.
Measurements of proton structure functions made in neutral and charged current interactions at HERA are discussed, covering four-momentum transfers Q^2 from about 0.5 GeV^2 to 30000 GeV^2. The results include the rise of the structure function F2 towards small x and electro-weak effects at high Q^2. QCD fits made by the H1 and ZEUS collaborations provide both, parton densities with uncertainties, and precise alpha_s determinations.
Results on the derivative of log(F_2) with respect to log(x) at fixed Q^2 are presented. The measured derivatives are within errors independent of x for Q^2 >= 0.85 GeV^2 and increase linearly with log(Q^2) for 0.0001 <= x <= 0.01 and Q^2 >= 3 GeV^2. The results are based on preliminary and published H1 data which at Q^2 below 2 GeV^2 are combined with NMC and ZEUS data.
Recent results from the HERA ep collider are discussed with emphasis on the transition from short to long distance phenomena in QCD. The results cover inclusive ep scattering, inclusive diffractive scattering, vector meson production, and deeply virtual Compton scattering (DVCS).
Data on jet production in deep inelastic e^+ p scattering are presented. The results are compared with pQCD calculations. At low Q^2 no consistent description of the data over all the phase space is available yet. At high Q^2 (>150 GeV^2) the data are well described by pQCD in NLO.