Based on the full BABAR data sample, we report improved measurements of the ratios R(D(*))=B(B[over ¯]→D(*)τ(-)ν[over ¯](τ))/B(B[over ¯]→D(*)ℓ(ℓ)(-)ν[over ¯](ℓ)), where ℓ is either e or μ. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D)=0.440±0.058±0.042 and R(D(*))=0.332±0.024±0.018, which exceed the standard model expectations by 2.0σ and 2.7σ, respectively. Taken together, our results disagree with these expectations at the 3.4σ level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

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Recent investigations have suggested that the six-quark combination uuddss could be a deeply bound state (S) that has eluded detection so far, and a potential dark matter candidate. We report the first search for a stable, doubly strange six-quark state in Υ → S Λ Λ decays based on a sample of 90 × 10 6 Υ (2S) and 110 × 10 6 Υ (3S) decays collected by the BABAR experiment. No signal is observed, and 90% confidence level limits on the combined Υ (2S, 3S) → S Λ Λ branching fraction in the range (1.2 − 1.4) × 10 −7 are derived for mS < 2.05 GeV. These bounds set stringent limits on the existence of such exotic particles.