Status and perspectives of photoproduction experiments

Three lectures on photoproduction are presented. Topics covered are: the photoproduction of pseudoscalar mesons in the isobar region; the photoproduction of vector mesons; and the photoproduction of pseudoscalar mesons at high energies. (GHT

Quadratic electroweak corrections for polarized Moller scattering

The paper discusses the two-loop (NNLO) electroweak radiative corrections to the parity violating electron-electron scattering asymmetry induced by squaring one-loop diagrams. The calculations are relevant for the ultra-precise 11 GeV MOLLER experiment planned at Jefferson Laboratory and experiments at high-energy future electron colliders. The imaginary parts of the amplitudes are taken into consideration consistently in both the infrared-finite and divergent terms. The size of the obtained partial correction is significant, which indicates a need for a complete study of the two-loop electroweak radiative corrections in order to meet the precision goals of future experiments

SU(3) assignment and coupling of N*(1688)

A comparison of the two reactions γ + p → n + p and γ + p → π0 + p in the region of the third nucleon isobar N***(1688) has produced evidence that (1) N***(1688) is a member of a unitary octet, and (2) the D/F ratio, which relates the couplings N***N π and N***Nn, is similar to that which relates NN π and NNn

One-loop chiral amplitudes of Moller scattering process

The high energy amplitudes of the large angles Moller scattering are calculated in frame of chiral basis in Born and 1-loop QED level. Taking into account as well the contribution from emission of soft real photons the compact relations free from infrared divergences are obtained. The expressions for separate chiral amplitudes contribution to the cross section are in agreement with renormalization group predictions.Comment: 15 pages, 3 figure

THE 18O + 12C FUSION-EVAPORATION REACTION

No abstract availabl

Theoretical Aspects of Standard-Model Higgs-Boson Physics at a Future e^+ e^- Linear Collider

The Higgs boson is the missing link of the Standard Model of elementary particle physics. We review its decay properties and production mechanisms at a future e^+ e^- linear collider and its e^- e^-, e^+- gamma, and gamma gamma modes, with special emphasis on the influence of quantum corrections. We also discuss how its quantum numbers and couplings can be extracted from the study of appropriate final states.Comment: 23 pages (Latex), 15 figures (Postscript), to appear in Int. J. Mod. Phys.

Single WRW_R Production in e−e−e^-e^- Collisions at the NLC

Single $W_R$ production in $e^-e^-$ collisions at the NLC can be used to probe the Majorana nature of the heavy neutrinos present in the Left-Right Symmetric Model below the kinematic threshold for their direct production. For colliders in the $\sqrt {s}=1-1.5$ TeV range, typical cross sections of order $1-10 fb$ are obtained, depending on the specific choice of model parameters. Backgrounds arising from Standard Model processes are shown to be small. This analysis greatly extends the kinematic range of previous studies wherein the production of an on-shell, like-sign pair of $W_R$'s at the NLC was considered.Comment: 13pp, 3 figures (available on request), LaTex, SLAC-PUB-647