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The European physical journal / H 47(1), 16 (2022). doi:10.1140/epjh/s13129-022-00047-8, The JADE experiment was one of five large detector systems taking data at the electron-positron collider PETRA, from 1979 to 1986, at $e^+e^-$ annihilation centre-of-mass energies from 12 to 46.7 GeV. The forming of the JADE collaboration, the construction of the apparatus, the most prominent physics highlights, and the post-mortem resurrection and preservation of JADE's data and software are reviewed., Published by Springer, Heidelberg

Universität Hamburg, Diss., 2003; 192 pp., (2003). doi:10.3204/DESY-THESIS-2003-037, Published by Deutsches Elektronen-Synchrotron, DESY, Hamburg

14 pp. (2002)., We consider $J/\psi$ photoproduction in $e^+ e^-$ as well as linear photon colliders. We find that the process is dominated by the resolved photon channel. Both the once-resolved and twice-resolved cross-sections are sensitive to (different combinations of) the colour octet matrix elements. Hence, this may be a good testing ground for colour octet contributions in NRQCD. On the other hand, the once-resolved J/psi production cross-section, particularly in a linear photon collider, is sensitive to the gluon content of the photon. Hence these cross-sections can be used to determine the parton distribution functions, especially the gluon distribution, in a photon, if the colour octet matrix elements are known.

5 pp. (2001)., A comparison of the potentials of ep and $e^+e^-$machines to probe the structure of the photon is performed. In particular, the kinematic reach of a proposed future ep facility, THERA, is compared with those of current colliders, LEP and HERA, and with the proposed linear collider, TESLA. THERA like HERA will use a proton beam of 920 GeV but with an increased electron beam energy of 250 GeV allowing higher scales, $Q^2$, and lower values of parton momentum fraction in the photon, x_\gamma, to be probed.

11 pp. (2001)., Previous studies of the kinematic coverage for measuring the photon structure function $F_2^\gamma$ at a future 500 GeV $e^+e^−$ linear collider [1, 2] are updated using current estimates of luminosities and important detector parameters. A simple illustration is given of the sensitivity of the photonic structure functions on the strong coupling constant $\alpha_s$.

8 pp. (2000)., A parametrization of the real photon structure function $F_2^\gamma$ in the low $Q^2$, low $x$ region is formulated. It includes both the vector meson dominance (VMD) and the QCD components, the latter suitably extrapolated to the low $Q^2$ region and based on arbitrary parton distributions in the photon. The parametrization used together with the Gluck, Reya, and Vogt (GRV) and Gluck, Reya, and Schienbein (GRS) parton densities describes reasonably well the existing high energy data on $F_2^\gamma$, $\sigma_{\gamma\gamma}$, and the low $Q^2$ data on $\sigma_{\gamma^* \gamma}$. Predictions for $\sigma_{\gamma\gamma}$ and for $\sigma_{\gamma^*\gamma}$ for energies which may become accessible in future linear colliders are also given.

8 pp. (1999)., A summary is presented of the key strong-interaction measurements that could be made at a high-energy, high-luminosity $e^+e^-$ collider

440303 152 pp. (1997).

Universität Hamburg, Diss., 1996; 128 pp. (1996). = Universität Hamburg, Diss., 1996

11 pp. (1995)., The next-to-leading order inclusive cross section for large- p ⊥ photoproduction of charm quarks at HERA is calculated in two different approaches. In the first approach the charm quarks are treated as massive objects which are strictly external to the proton and the photon while in the second approach the charm mass is neglected and the c quark is assumed to be one of the active flavours in the proton and photon structure functions. We present single-inclusive distributions in transverse momentum and rapidity including direct and resolved photons. The cross section in the massless approach is found to be significantly larger than in the massive scheme. The deviation originates from several contributions which are disentangled. We argue that large- p ⊥ photoproduction of charm quarks at HERA will be sensitive to the charm content of the photon structure function.

Proceedings, Workshop, Annecy, Gran Sasso, Hamburg, Hamburg, Germany, 4 Feb 1995 - 1 Sep 1995 ; (1995).

23 pp. (1994)., We present results for next-to-leading order calculations of single jet inclusive cross sections by resolved photons inep-collisions at HERA. The dependence on the jet recombination cut and on the choice of the renormalization and factorization scales is studied in detail.

15 pp. (1994)., We have calculated high transverse energy single-jet inclusive cross sections for γp-collisions at next-to-leading order superimposing direct and resolved photoproduction. The dependence on the scale and the scheme for the factorization of the photon structure is studied quantitatively. The accuracy of the predictions due to variations of all scales is investigated.

University of Toronto, Diss., 1994; 132 pp. (1994). = University of Toronto, Diss., 1994

11 pp. (1993)., We calculate in next-to-leading order inclusive cross sections of single-particle production via resolved photons inep collisions at HERA. Transverse-momentum and rapidity distributions are presented and the scale dependence is studied. The results are compared with first experimental data from the H1 Collaboration at HERA.

Universität Hamburg, Diss., 1993; 83 pp. (1993). = Universität Hamburg, Diss., 1993

30 pp. (1983).

4 pp. (1986).

155841 (1980)., The analysis of two photon physics at the e+e− storage ring PETRA is reviewed. Higher order QED processes e+e−→e+e−e+e−(e+e−μ+μ−) have been measured in good agreement with the QED calculations. The production of the f0 resonance has been invstigated and the radiative width has been determined. The total cross section σ(Q2,W) of the inelastic electron photon scattering has been studied in some detail. Evidence for the production of large PT jets in the reaction γγ→qq̄ is reported and a first measurement of the photon structure function in deep inelastic eγ scattering is discussed.

71 pp. (1986).

38 pp. (1983).

29 pp. (1982).

7 pp. (1979).

19 pp. (1983).

34 pp. (1983)., A total of 26 papers have been contributed to the experimental discussion session. I will discuss some of the tools needed for 2γ experimentation and then point to highlights and regions of particular

(1982). doi:10.1088/0031-8949/25/1B/011, Selected topics of recent experimental results from the high-energy electron-position storage rings are presented. The topics include some of the τ and charm physics from SPEAR, the upsilon physics from DORIS and CESR, and the γγ physics and quark and gluon physics from the PLUTO and TASSO Collaborations at PETRA. Related data from the JADE and MARK J Collaborations at PETRA are discussed in separate papers at this School.

61 pp. (1983).

40 pp. (1982).