Related papers: Lepton Universality Test in Upsilon(1S) decays at …
A recent analysis of the LEP data shows an interesting deviation from lepton universality in W boson decays. An excess at the level of 2.8 sigma is found in the tau mode branching ratio with respect to the other two modes. It is suggested…
We present recent results concerning the searches for light Higgs-like particles in the decay $\Upsilon (3S) \to \gamma A^{0}, A^{0}\to \mu^{+}\mu^{-}$ as well as for the lepton flavour violation in the decays $\Upsilon (3S) \to…
We search for di-muon decays of a low-mass Higgs boson ($A^0$) in the fully reconstructed decay chain of $\Upsilon(2S,3S) \to \pipi\Upsilon(1S)$, $\Upsilon(1S) \to \g A^0$, $A^0 \to \mumu$. The $A^0$ is predicted by several extensions of…
A measurement of the ratio of the branching fractions, $R_{\tau/e} = B(W \to \tau \nu)/ B(W \to e \nu)$, is performed using a sample of $W$ bosons originating from top-quark decays to final states containing $\tau$-leptons or electrons.…
We search for a new light non-Standard Model CP-odd Higgs boson, $A^0$, decaying to $\tau^+\tau^-$, $\mu^+\mu^-$, and invisible in radiative decays of the $\Upsilon(2S)$ and $\Upsilon(3S)$. We search for the light scalar particle produced…
We search for evidence of a light Higgs boson (A0) in the radiative decays of the narrow Upsilon(3S) resonance: Upsilon(3S) -> gamma A0, where A0 -> invisible or A0 -> mu+mu-. Such an object appears in extensions of the Standard Model,…
We search for a light Higgs boson ($A^0$) decaying into a $\tau^+\tau^-$ or $\mu^+\mu^-$ pair in the radiative decays of $\Upsilon(1S)$. The production of $\Upsilon(1S)$ mesons is tagged by $\Upsilon(2S)\to \pi^+ \pi^- \Upsilon(1S)$…
We present a search for the decay B+ -> tau+ nu using 288 inverse femtobarns of data collected at the Upsilon(4S) resonance with the BaBar detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed semileptonic B decay…
Using data collected with the BaBar detector between 1999 and 2001, we describe a preliminary search for the neutrinoless decay Tau to Mu Gamma. This data sample includes data collected both on and off the Upsilon(4S) resonance and…
We present a search for the decay B^+ --> tau^+ nu using $383 \times 10^{6}}$ BBbar pairs collected at the Upsilon(4S) resonance with the BABAR detector at the SLAC PEP-II B Factory. We select a sample of events with one completely…
We present a search for the decay B+ --> tau+ nu_tau using 467.8 x 10^6 B B-bar pairs collected at the Upsilon(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. We select a sample of events with one completely…
We present measurements of the semileptonic decays B- --> D0 tau- nubar_tau, B- --> D*0 tau- nubar_tau, B0bar --> D+ tau- nubar_tau, and B0bar --> D*+ tau- nubar_tau, which are sensitive to non--Standard Model amplitudes in certain…
We report on the search for the decay $\Upsilon(1S) \to \gamma A^0$, $A^0 \to gg$ or $s\bar s$, where $A^0$ is the pseudoscalar light Higgs boson predicted by the next-to-minimal supersymmetric standard model. A sample of $\sim 18 \times…
We search for a low-mass scalar CP-odd Higgs boson, A0, produced in the radiative decay of the Upsilon resonance and decaying into a tau+tau- pair: Upsilon(1S)->gamma A0. The production of Upsilon(1S) mesons is tagged by…
We present a search for the radiative leptonic decay B+ -> l+ nu gamma, where l=e,mu, using a data sample of 465 million B-meson pairs collected by the BABAR experiment. In this analysis, we fully reconstruct the hadronic decay of one of…
We present a search for the decay $B^{+} \to \tau^{+} \nu_{\tau}$ in $124.1 \times 10^{6}$ $\Upsilon(4S)$ decays recorded with the $BABAR$ detector at the SLAC PEP-II $B$-Factory. A sample of events with one reconstructed exclusive…
Using a sample of 122 million Upsilon(3S) events recorded with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we search for the $h_b(1P)$ spin-singlet partner of the P-wave chi_{bJ}(1P) states in the sequential…
In several extensions of the Standard Model, the top quark can decay into a bottom quark and a light charged Higgs boson H+, t to bH+, in addition to the Standard Model decay t to bW. Since W bosons decay to the three lepton generations…
Based on 471 million BB pairs collected with the BABAR detector at the PEP-II e+e- collider, we perform a series of measurements on rare decays B->K(*)l+l-, where l+l- is either e+e- or mu+mu-. The measurements include total branching…
A test of lepton universality, performed by measuring the ratio of the branching fractions of the $B^{0} \rightarrow K^{*0}\mu^{+}\mu^{-}$ and $B^{0} \rightarrow K^{*0}e^{+}e^{-}$ decays, $R_{K^{*0}}$, is presented. The $K^{*0}$ meson is…