Rare B decays and New Physics Searches at BaBar

Abstract

Flavor Changing Neutral Current transitions b→sγ and b→sl+l− provide an excellent laboratory for the search for physics beyond the Standard Model. Standard Model tests are performed through measurements of the B→Xsl+l− branching ratio, the B→Xsl+l− and B→Xsγ direct CP asymmetries, and the B0→Ks0π−π+γ time-dependent CP asymmetry.Strong constraints on the (tan⁡β,mH+) plane in the two-Higgs doublet models scenario are obtained from the measurements of the B+→τ+ν branching ratio and of the branching fractions ratio R(D(⁎))=B(B¯→D(⁎)τ−ντ¯)/B(B¯→D(⁎)l−νl¯), where l refers to either an electron or a muon.