The Gronau-London-Wyler (GLW) method extracts the CKM angle γ by measuring B ± decay rates involving D 0 /D 0 mesons. Since that method necessitates the interference between two amplitudes that are significantly different in magnitude, the resulting asymmetries tend to be small. CP violation can be greatly enhanced for decays to final states that are common to both D 0 and D 0 and that are not CP eigenstates. In particular, large asymmetries are possible for final states f such that D 0 → f is doubly Cabibbo suppressed while D 0 → f is Cabibbo allowed. The measurement of interference effects in two such modes allows the extraction of γ without prior knowledge of, which may be difficult to determine due to backgrounds.One striking implication of the standard model with three families is that it can accommodate CP violation via the Kobayashi-Maskawa mechanism [1]. Intense experimental efforts are now underway in B-physics to test the standard model in this regard through measurements of the unitarity triangle [2]. For this program to succeed it is of crucial importance to be able to deduce each of the angles of this triangle from experiment. In this paper we will focus our attention to one of the three angles, namely γ.We recall that in the standard model, b → cus and b → cus transitions have a relativeCabibbo-Kobayashi-Maskawa (CKM) phase γ. In order to measure CP violation due to this phase, a means must be found to have these seemingly distinct final states interfere. A mechanism whereby this is possible has been proposed and extensively studied [3,4,5,6,7,8].

A comprehensive phenomenological analysis of a two Higgs doublet model, with flavor-changing scalar currents at the tree-level, called model III, is presented. Constraints from existing experimental information especially on ∆F = 2 processes are systematically incorporated. Constraints emerging from rare B-decays, Z → b b, and the ρ-parameter are also examined. Experimental implications for e + e − (µ + µ − ) → tc + tc, t → cγ(Z, g), D 0 -D0 , and B 0 s -B0 s oscillations, and for e + e − (Z) → bs + bs are investigated and experimental effort towards these is stressed. We also emphasize the importance of clarifying the experimental issues pertaining to Z → b b.

Phenomenological analysis for determining the magnetic moment and electic dipole moment form factors of the top quark via the reaction e 'e--tT, followed by the decays t + b w f and T -+~w -, is presented, with analytic expressions for the differential cross section and decay given. Various experimental observables are studied and their efficacy for the determination of form factors is considered and compared with the optimal resolution of form factors in the tSj and tiZ vertices. We find that with a sample of 10000 events it is possible to put limits of lo-"e cm for the form factors considered, evaluated at q 2 = s when 6 =SO0 GeV.

In the Standard Model (SM) the photon in radiativeB 0 andB s decays is predominantly left-handed. Thus, mixing induced CP asymmetries in b → sγ and b → dγ are suppressed by m s /m b and m d /m b , respectively, and are very small. In many extensions of the SM, such as the left-right symmetric model (LRSM), SU(2) × U(1) models with exotic fermions and SUSY, the amplitude of right-handed photons grows proportional to the virtual heavy fermion mass, which can lead to large asymmetries. As an example, in the LRSM, asymmetries larger than 50% are possible even when radiative decay rate measurements agree with SM predictions.

Various methods are discussed for obtaining the CKM angle ␥ through the interference of the charged B-meson decay channels B Ϫ →K Ϫ D 0 and B Ϫ →K Ϫ D 0 where the D 0 and D 0 decay to common final states. It is found that choosing final states which are not CP eigenstates can lead to large direct CP violation which can give significant bounds on ␥ without any theoretical assumptions. If two or more modes are studied, ␥ may be extracted with a precision on the order of Ϯ15°given ϳ10 8 B-mesons. We also discuss the case of three body decays of the D where additional information may be obtained from the distribution of the D decay products and consider the impact of DD oscillations.

Mechanisms for the observed large Br(B → η ′ + X s ) are examined. We propose that the dominant fraction of the B → η ′ + X s rate is due mainly to b → sg * , where g * is an off-shell gluon, followed by g * → gη ′ via the anomalous coupling of the η ′ to two gluons. The calculated rate for B → η ′ + X s is in rough accord with experiment using a fairly constant glueglue-η ′ form factor. This behavior of the form factor may be indicative of glueball dominance of the channel. Searches via the modes η ′ h + h − (h = π or K) may be worthwhile. Charmonia contributions [i.e B → η c , ψ(→ η ′ + X) + X s ] can only account for at most 20% of the central value of the signal. Implications for B → η ′ +X d and for the corresponding η modes are also given. IntroductionRecently CLEO has reported[1] a very large branching ratio for the inclusive production of η ′ (subject to the indicated cut):In this Letter we report on possible mechanisms for this large signal. Two interesting origins are: (1) b → s + g * (where g * is an off-shell gluon) followed by g * → η ′ + g due to the anomalous η ′ -g-g vertex. (2) b → charmonia (e.g. ψ, η c ) + X s followed by ψ(η c ) → η ′ + X. We discuss these below in turn.

CP violation in top physics is reviewed. The Standard Model has negligible effects, consequently CP violation searches involving the top quark may constitute the best way to look for physics beyond the Standard Model. Non-standard sources of CP violation due to an extended Higgs sector with and without natural flavor conservation and supersymmetric theories are discussed. Experimental feasibility of detecting CP violation effects in top quark production and decays in high energy e + e − , γγ, µ + µ − , pp and pp colliders are surveyed. Searches for the electric, electro-weak and the chromo-electric dipole moments of the top quark in e + e − → tt and in pp → ttX are descibed. In addition, other mechanisms that appear promising for experiments, e.g., tree-level CP violation in e + e − → tth, ttZ, ttν eνe and in the top decay t → bτ ν τ and CP violation driven by s-channel Higgs exchanges in pp, γγ, µ + µ − → tt etc., are also discussed. * A 2-up version of this postscript file may be obtained at the url

Oscillation effects in B 0 →K S D 0 and related processes are considered to determine ␦ϵ␤Ϫ␣ϩϭ2␤ ϩ␥. We suggest that D 0 decays to CP eigenstates used in concert with inclusive D 0 decays provide a powerful method for determining ␦ cleanly. The CP asymmetry is expected to be Շ40% for D 0 decays to non-CP eigenstates and Շ80% for decays to CP eigenstates. This method can lead to a fairly accurate determination of ␦ with O(10 8 Ϫ10 9 ) B mesons.The two asymmetric B factories have made remarkable progress in determining one of the angles (␤) of the unitarity triangle; the world average now stands at sin 2␤ WA ϭ0.78 Ϯ0.08 ͓1,2͔. This is in very good agreement with the expectations from the standard model ͑SM͒, sin 2␤ SM ϭ0.70 Ϯ0.10 ͓3͔. However, a considerable amount of theoretical input has to be used to deduce sin 2␤ SM and progress in reducing the theory error is likely to be rather slow. Thus, methods that determine the angles without the uncertainties of hadronic matrix elements are crucial in testing the Cabibbo-Kobayashi-Maskawa ͑CKM͒ paradigm ͓4͔ to an increasing degree of accuracy in an effort to search for CP-odd phase͑s͒ due to physics beyond the SM.In the SM, CP violation is controlled by only one CP-odd phase. Therefore, different decays which measure the same angle of the unitarity triangle ͑UT͒ may give inconsistent results if physics beyond the SM is present. Likewise another apparent failure of unitarity of the CKM matrix, such as the failure of the UT to close, would also indicate new physics. Beyond the phase ␤, the determinations of ␣ and ␥, therefore, provide key SM tests.Two extensively studied methods for determining ␣ already exist, via B→ ͓5͔ and B→ ͓6͔. In these approaches, in addition to some experimental difficulties, considerable theoretical input is essential as these modes receive large QCD-penguin as well as some electroweak penguin ͑EWP͒ contributions. While efforts at these methods should certainly continue, it is also very important that, in our drive towards precision, we develop methods that do not require theoretical assumptions and therefore have negligible theory error. The key point is that the effect of beyond the SM CP-odd phase͑s͒ on B-physics may be quite small so any residual theory error on the determined unitarity angles may mask the effect of new physics and thwart experimental searches ͓7͔.The processes we consider ͑e.g. B 0 →K S D 0 ) use interference between b→u and b→c tree graphs; no penguin contribution, strong or EW, is involved ͓8͔. Time dependent CP-asymmetry measurements in B 0 (B 0 )→K S D 0 will give the combination of the unitarity angles ␦ϵ␤Ϫ␣ϩ, independent of the unitarity of the CKM matrix. If, however, one assumes unitarity of the CKM matrix then one also has, ␦ ϭ2␤ϩ␥ ͓9͔. Given that ␤ is already well measured, this method is very effective in determining ␣ ''cleanly,'' i.e. without QCD complications. In addition, this method can also be used to simultaneously extract ␤, allowing a crucial check against the value of ␤ determined with the B →J/K S 0 appr...