High-precision analyses of supersymmetry parameters aim at reconstructing the fundamental supersymmetric theory and its breaking mechanism. A well defined theoretical framework is needed when higher-order corrections are included. We propose such a scheme, Supersymmetry Parameter Analysis SPA, based on a consistent set of conventions and input parameters. A repository for computer programs is provided which connect parameters in different schemes and relate the Lagrangian parameters to physical observables at LHC and high energy e + e − linear collider experiments, i.e., masses, mixings, decay widths and production cross sections for supersymmetric particles. In addition, programs for calculating high-precision low energy observables, the density of cold dark matter (CDM) in the universe as well as the cross sections for CDM search experiments are included. The SPA scheme still requires extended efforts on both the theoretical and experimental side before data can be evaluated in the future at the level of the desired precision. We take here an initial step of testing the SPA scheme by applying the techniques involved to a specific supersymmetry reference point.

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

We study the production of charginos e + e − →χ + iχ − j , (i, j = 1, 2) with polarized beams and the subsequent decaysχ. . , 4), including the complete spin correlations between production and decay. Analytical formulae are presented for the joint spin-density matrix of the charginos, for the chargino decay matrix and for the differential cross section of the combined processes of production and decays. We present numerical results for pair production of the lighter chargino with unpolarized beams and the leptonic decay ofχ − 1 into the lightest neutralinoχ 0 1 . The lepton angular distribution and the forward-backward asymmetry are studied in four representative scenarios for √ s = 192 GeV and √

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.

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As has been shown almost two years ago , generalized vector dominance (GVD) quite successfully quantitatively accounts for the data on deep inelastic electron nucleon scattering. There is, however, one principal feature within this approach, which became more and more unsatisfactory as progressively higher energy data on e+e-+hadrons became available: these showing roughly a 1/s law in the Frascatil 3 1range, and an even slower fall off for c.m. energies /8 beyond about 3.5 GeV has been reported by CEAI 4 1 and more recently by the SLAC-LBL collaboration at SPEARisl. The problem, as discussed in I 1 I, with a 1/s law for e+e-annihilation is that in the usual diagonal form of GVD (i. then for p''(1600) photoproduction one expectswhere the addition.e e ann1h1lat1on result Experimentally one finds I 11 I Denoting the ratio of the first off-diagonal to the diagonal (t = 0) transition amplitude as (3) we thus obtain the isovector photon part of the transverse virtual photon ab- which for large N gives (negJ.ecting order I/~)Then the sum in (4) turns out to be convergent, provided the constant in (5) and (6) is chosen to be 1/2. Thus inserting (2) and (6) 2Generalizing to include the isoscalar parts and evaluating (7) The only free parameter introduced, o, which fixes the magnitude of the off-diagonal transitions, may now be determined fromfue normalization ( Although (II) may easily be evaluated numerically from the tables for 1/J (z), it is advantageous to give a much simp lac formula for oT' which for A = 2 approximates (II) extremely well, the error being at most 2% (around (13). (14) -6 -It is amusing to note that the simple pole formula (14) which is equivalent to(ll); had p~evi~u~~y'fgf be~n ~how~::tO'to de~c~ib~ extremely weilthe.•. Agreement of (II) and (14) •· are substantially unchanged.From our Ansatz (5), we note that diffraction dissociation, as exemplified by a single, effective off-diagonal term parametrized with CN, increases with N, becoming a constant fraction of the elastic reaction. This feature seems a necessary one for convergence and scaling. We have checked that a constant, N independent CN gives a logarithmically divergent non-scaling expression except for the singular point CN = 1/2, for which case the result is convergent, but also non-scaling with a leading term proportional to (1/q 4 ) ln (q 2 tm 2 ).

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A phenomenological study of diffractive ~p production by neutrinos in the A , region is performed. The difference between resonant and nonresonant (Deck-type) production is worked out. Interference effects are included. Numerical results for the mass and decay angular distributions are given.