The proposed International Linear Collider (ILC) is well-suited for discovering physics beyond the Standard Model and for precisely unraveling the structure of the underlying physics. The physics return can be maximized by the use of polarized beams. This report shows the paramount role of polarized beams and summarizes the benefits obtained from polarizing the positron beam, as well as the electron beam. The physics case for this option is illustrated explicitly by analyzing reference reactions in different physics scenarios. The results show that positron polarization, combined with the clean experimental environment provided by the linear collider, allows to improve strongly the potential of searches for new particles and the identification of their dynamics, which opens the road to resolve shortcomings of the Standard Model. The report also presents an overview of possible designs for polarizing both beams at the ILC, as well as for measuring their polarization.2

High energy photon colliders (γγ,γe) are based on e-e-linear colliders where high energy photons are produced using Compton scattering of laser light on high energy electrons just before the interaction point. This paper is a part of the Technical Design Report of the linear collider TESLA.1Physics program, possible parameters and some technical aspects of the photon collider at TESLA are discussed.

The purpose of this paper is to present a complete and consistent list of the Feynman rules for the vertices of neutralinos and Higgs bosons in the Next-To-Minimal Supersymmetric Standard Model (NMSSM), which does not yet exist in the literature. The Feynman rules are derived from the full expression for the Lagrangian and the mass matrices of the neutralinos and Higgs bosons in the NMSSM. Some crucial differences between the vertex functions of the NMSSM and the Minimal Supersymmetric Standard Model (MSSM) are discussed.

Within the framework of the Next-To-Minimal Supersymmetric Standard Model (NMSSM) we study neutralino production e + e − −→χ 0 iχ 0 j (i, j = 1, . . . , 5) at center-of-mass energies between 100 and 600 GeV and the decays of the heavier neutralinos into the LSP plus a fermion pair, a photon or a Higgs boson. For representative gaugino/higgsino mixing scenarios, where the light neutralinos have significant singlet components, we find some striking differences between the NMSSM and the minimal supersymmetric model. Since in the NMSSM neutralino and Higgs sector are strongly correlated, the decay of the second lightest neutralino into a Higgs boson and the LSP often is kinematically possible and even dominant in a large parameter region of typical NMSSM scenarios. Also, the decay rates into final states with a photon may be enhanced.November 1995 *

We analyze the experimental data from the search for new particles at LEP 100 and obtain mass bounds for the neutralinos of the Next-To-Minimal Supersymmetric Standard Model (NMSSM). We find that for tan β ∼ > 5.5 a massless neutralino is still possible, while the lower mass bound for the second lightest neutralino corresponds approximately to that for the lightest neutralino in the Minimal Supersymmetric Standard Model (MSSM).