decays allows one to obtain the CP-violating phase α. In addition, one can extract the various tree (T ) and penguin (P ) amplitudes contributing to these decays. By comparing the measured value of |P/T | with the theoretical prediction, one can detect the presence of physics beyond the standard model. 1 veronique.page@umontreal.ca 2

Recently, it was argued that new-physics (NP) effects in B decays can be approximately parametrized in terms of a few quantities. As a result, CP violation in the B system allows one not only to detect the presence of new physics (NP), but also to measure its parameters. This will allow a partial identification of the NP, before its production at high-energy colliders. In this paper, we examine three methods for measuring NP parameters. The first uses a technique involving bothb →s and b →d penguin B decays. Depending on which pair of decays is used, the theoretical error is in the range 5-15%. The second involves a comparison of B → πK and B → ππ decays. Although the theoretical error is large ( > ∼ 25%), the method can be performed now, with presently-available data. The third is via a time-dependent angular analysis of B → V 1 V 2 decays. In this case, there is no theoretical error, but the technique is experimentally challenging, and the method applies only to those NP models whose weak phase is universal to all NP operators. A reliable identification of the NP will involve the measurement of the NP parameters in many different ways, and with as many B decay modes as possible, so that it will be important to use all of these methods.

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We argue that the superpartner of the Dirac right-handed neutrino is a prime candidate for dark matter created from a 'mattergenesis' mechanism. We show that due to the smallness of the Yukawa couplings, a right-handed sneutrino density created in the early Universe would not be erased by annihilations, which remain out of thermal equilibrium. It would also not be drowned by a later, additional production of right-handed sneutrinos, as the relic density of the non-thermal right-handed sneutrinos is found to be generally negligible compared to the observed dark matter density. Mild constraints on sneutrino masses and trilinear SUSY-breaking couplings are obtained. Possible mattergenesis scenarios are also mentioned

We consider the Affleck-Dine mechanism for leptogenesis in the minimal MSSM with Dirac or Pseudo-Dirac neutrinos. The rolling of scalars along D-flat directions generates a left-right asymmetry in the sneutrino sector, only the left part of which is transferred to a baryon asymmetry via sphaleron transitions. In the pure Dirac case the baryon asymmetry of the Universe is thus mirrored by an equal and opposite asymmetry in the leptons. The mechanism is also found to work when the neutrinos are pseudo-Dirac. No additional field needs to be added to the MSSM other than the right-handed neutrino.