In most supersymmetric theories charginos,χ ± 1,2 , belong to the class of the lightest supersymmetric particles. The chargino system can be reconstructed completely in e + e − collider experiments: e + e − →χ. By measuring the total cross sections and the asymmetries with polarized beams, the chargino masses and the gaugino-higgsino mixing angles of these states can be determined accurately. If only the lightest charginosχ ± 1 are kinematically accessible in a first phase of the machine, transverse beam polarization or the measurement of chargino polarization in the final state is needed to determine the mixing angles. From these observables the fundamental SUSY parameters can be derived: the SU(2) gaugino mass M 2 , the modulus and the cosine of the CP-violating phase of the higgsino mass parameter µ, and tan β = v 2 /v 1 , the ratio of the vacuum expectation values of the two neutral Higgs doublet fields. The remaining two-fold ambiguity of the phase can be resolved by measuring the normal polarization of the charginos. Sum rules of the cross sections can be exploited to investigate the closure of the two-chargino system.

We investigate all the four-body graviton interaction processes: gX → γX, gX → gX, and gg → gg with X as an elementary particle of spin less than two in the context of linearized gravity except the spin-3/2 case. We show explicitly that gravitational gauge invariance and Lorentz invariance cause every four-body graviton scattering amplitude to be factorized. We explore the implications of this factorization property by investigating polarization effects through the covariant density matrix formalism in each four-body graviton scattering process. PACS number(s) : 04.60.+n, 12.25.+e, 13.88.+e

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Photoproduction of J/ψ is considered including the color-octet contributions from the various partial wave states, 2S+1 L J = 1 S 0 , 3 S 1 and 3 P J . The production cross section depends on three new nonperturbative parameters defined in NRQCD, called the color-octet matrix elements. Using the color-octet matrix elements determined by fitting the J/ψ production at the Tevatron, we find that the color-octet (cc) 8 ( 1 S 0 and 3 P J ) contributions to the J/ψ photoproductions at the fixed target experiments and HERA are too large compared to the data on σ(γ + p → J/ψ + X) in the forward direction, the z distribution of J/ψ. The P 2 T distribution of J/ψ and the total inelastic J/ψ production rate as a function of √ s γp are predicted including color-octet contributions. We also briefly digress on the B → J/ψ + X and observe the similar situation. This may be an indication that the color-octet matrix elements determined from the J/ψ production at the Tevatron, especially 0|O ψ 8 ( 1 S 0 )|0 and 0|O ψ 8 ( 3 P J )|0 , might have been overestimated by an order of magnitude.

At the order of 1/m 3 b , the B meson lifetimes are controlled by the hadronic matrix elements of some four-quark operators. The nonfactorizable magnitudes of these four-quark operator matrix elements are analyzed by QCD sum rules in the framework of heavy quark effective theory. The vacuum saturation for color-singlet four-quark operators is justified at hadronic scale, and the nonfactorizable effect is at a few percent level.However for color-octet four-quark operators, the vacuum saturation is violated sizably that the nonfactorizable effect cannot be neglected for the B meson lifetimes. The implication to the extraction of some of the parameters from B decays is discussed. The B meson lifetime ratio is predicted as τ (B − )/τ (B 0 ) = 1.09 ± 0.02. However, the experimental result of the lifetime ratio τ (Λ b )/τ (B 0 ) still cannot be explained.