W. T. Ford

Searches for lepton-flavor-violating decays of a tau lepton to a lighter mass lepton and a photon have been performed with the entire data set of (963+/-7)x10{6} tau decays collected by the BABAR detector near the Upsilon(4S), Upsilon(3S) and Upsilon(2S) resonances. The searches yield no evidence of signals and we set upper limits on the branching fractions of B(tau{+/-}-->e{+/-}gamma)<3.3x10{-8} and B(tau{+/-}-->mu{+/-}gamma)<4.4x10{-8} at 90% confidence level.

Dark sectors charged under a new Abelian force have recently received much attention in the context of dark matter models. These models introduce a light new mediator, the so-called dark photon (A'), connecting the dark sector to the Standard Model. We present a search for a dark photon in the reaction e+e- -> gamma A', A'-> e+e-, mu+mu- using 514 fb-1 of data collected with the BABAR detector. We do not observe a significant signal and we set 90% confidence level upper limits on the mixing strength between the photon and dark photon at the level of 10^-4 - 10^-3 for dark photon masses in the range 0.02 - 10.2 GeV. We further constrain the range of the parameter space favored by interpretations of the discrepancy between the calculated and measured anomalous magnetic moment of the muon.

We have observed fourteen events in which two muons are produced by high-energy neutrino and antineutrino interactions. The absence of trimuon events and the observed characteristics of the dimuon events require the existence of one or more new massive particles that decay through the weak interaction. The new particle mass is estimated to lie between 2 and 4 GeV.

We report the observation of inelastic interactions induced by high-energy neutrinos and antineutrinos in which no muon is observed in the final state. A possible, but by no means unique, interpretation of this effect is the existence of a neutral weak current.

From a sample of hadronic events produced in e+e− collisions, semileptonic decays of heavy particles have been isolated and used to obtain a measurement for the bottom-quark lifetime of [1.8±0.6 (stat.)±0.4(syst.)]×10−12 sec.Received 30 June 1983DOI:https://doi.org/10.1103/PhysRevLett.51.1022©1983 American Physical Society

Using a quadrupole focused neutrino beam, 61 events with two muons in the final state have been observed at Fermilab. These include seven ${\ensuremath{\mu}}^{\ensuremath{-}}{\ensuremath{\mu}}^{\ensuremath{-}}$ events. A comparison of the event rate in two targets of different hadron absorption length indicates that attributing the events to $\ensuremath{\pi}$ or $K$ leptonic decay is ruled out by 4.0 standard deviations. No trimuon events were observed which, combined with lepton conservation, indicates an unobserved neutral lepton is present in most of the events.

We search for evidence of a light scalar boson in the radiative decays of the Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-->gammaA0, A0-->mu+mu-. Such a particle appears in extensions of the standard model, where a light CP-odd Higgs boson naturally couples strongly to b quarks. We find no evidence for such processes in the mass range 0.212 < or = mA0 < or = 9.3 GeV in the samples of 99 x 10(6) Upsilon(2S) and 122 x 10(6) Upsilon(3S) decays collected by the BABAR detector at the SLAC PEP-II B factory and set stringent upper limits on the effective coupling of the b quark to the A0. We also limit the dimuon branching fraction of the etab meson: B(etab-->mu+mu-)<0.9% at 90% confidence level.

We have measured the mass of the Z boson to be 91.14±0.12 GeV/c2, and its width to be 2.42+0.45−0.35 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.46±0.10 GeV, corresponding to 2.8±0.6 neutrino species, with a 95%-confidence-level upper limit of 3.9.Received 12 October 1989DOI:https://doi.org/10.1103/PhysRevLett.63.2173©1989 American Physical Society

Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B(0) or B(0)), and J/ψK(L)(0) or ccK(S)(0) final states (referred to as B(+) or B(-)), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, B(0) → B(-) and B(-) → B(0), as a function of the time difference between the two B decays. Using 468 × 10(6) BB pairs produced in Υ(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding ΔS(T)(+) = -1.37 ± 0.14(stat) ± 0.06(syst) and ΔS(T)(-) = 1.17 ± 0.18(stat) ± 0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation.

We search for the flavor-changing neutral-current decays $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, and the invisible decays $J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ and $\ensuremath{\psi}(2S)\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ via $B\ensuremath{\rightarrow}{K}^{(*)}J/\ensuremath{\psi}$ and $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\psi}(2S)$, respectively, using a data sample of $471\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected by the BABAR experiment. We fully reconstruct the hadronic decay of one of the $B$ mesons in the $\ensuremath{\Upsilon}(4S)\ensuremath{\rightarrow}B\overline{B}$ decay, and search for the $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ decay in the rest of the event. We observe no significant excess of signal decays over background and report branching fraction upper limits of $\mathcal{B}({B}^{+}\ensuremath{\rightarrow}{K}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;3.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, $\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{K}^{0}\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;8.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, $\mathcal{B}({B}^{+}\ensuremath{\rightarrow}{K}^{*+}\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;11.6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, $\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{K}^{*0}\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;9.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, and combined upper limits of $\mathcal{B}(B\ensuremath{\rightarrow}K\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;3.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$ and $\mathcal{B}(B\ensuremath{\rightarrow}{K}^{*}\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;7.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, all at the 90% confidence level. For the invisible quarkonium decays, we report branching fraction upper limits of $\mathcal{B}(J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;3.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ and $\mathcal{B}(\ensuremath{\psi}(2S)\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}})&lt;15.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ at the 90% confidence level. Using the improved kinematic resolution achieved from hadronic reconstruction, we also provide partial branching fraction limits for the $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ decays over the full kinematic spectrum.

We present a study of the ${D}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, ${D}^{0}{\ensuremath{\pi}}^{+}$, and ${D}^{*+}{\ensuremath{\pi}}^{\ensuremath{-}}$ systems in inclusive ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}c\overline{c}$ interactions in a search for new excited $D$ meson states. We use a data set, consisting of $\ensuremath{\sim}454\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$, collected at center-of-mass energies near 10.58 GeV by the BABAR detector at the SLAC PEP-II asymmetric-energy collider. We observe, for the first time, candidates for the radial excitations of the ${D}^{0}$, ${D}^{*0}$, and ${D}^{*+}$, as well as the $L=2$ excited states of the ${D}^{0}$ and ${D}^{+}$, where $L$ is the orbital angular momentum of the quarks.

The high-$y$ anomaly in inelastic ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$-nucleon scattering is shown to exhibit effective violations of scale invariance and charge-symmetry invariance. The anomaly cannot be explained by scattering from antiquarks in the usual three-quark model.

We describe a measurement of the time-integrated luminosity of the data collected by the BABAR experiment at the PEP-II asymmetric-energy e+e- collider at the ϒ(4S), ϒ(3S), and ϒ(2S) resonances and in a continuum region below each resonance. We measure the time-integrated luminosity by counting e+e-→e+e- and (for the ϒ(4S) only) e+e-→μ+μ- candidate events, allowing additional photons in the final state. We use data-corrected simulation to determine the cross-sections and reconstruction efficiencies for these processes, as well as the major backgrounds. Due to the large cross-sections of e+e-→e+e- and e+e-→μ+μ-, the statistical uncertainties of the measurement are substantially smaller than the systematic uncertainties. The dominant systematic uncertainties are due to observed differences between data and simulation, as well as uncertainties on the cross-sections. For data collected on the ϒ(3S) and ϒ(2S) resonances, an additional uncertainty arises due to ϒ→e+e-X background. For data collected off the ϒ resonances, we estimate an additional uncertainty due to time dependent efficiency variations, which can affect the short off-resonance runs. The relative uncertainties on the luminosities of the on-resonance (off-resonance) samples are 0.43% (0.43%) for the ϒ(4S), 0.58% (0.72%) for the ϒ(3S), and 0.68% (0.88%) for the ϒ(2S).

We study the reactions e+e−→e+e−η(') in the single-tag mode and measure the γγ∗→η(') transition form factors in the momentum-transfer range from 4 to 40 GeV2. The analysis is based on 469 fb−1 of integrated luminosity collected at PEP-II with the BABAR detector at e+e− center-of-mass energies near 10.6 GeV.11 MoreReceived 5 January 2011DOI:https://doi.org/10.1103/PhysRevD.84.052001© 2011 American Physical Society

<h2>Abstract</h2><h3>Background</h3> Acute bacterial skin and skin structure infections (ABSSSI), formally referred to as complicated skin and soft tissue infections, include infections with resistance to previously effective antimicrobials. Increasing dramatically in incidence, they have become a challenging medical problem associated with high direct and indirect costs to both the medical system and society. <h3>Objectives</h3> To describe the burden of ABSSSI and to explore multidisciplinary approaches to its management and new treatments that can be initiated in the emergency department. <h3>Discussion</h3> We offer a best practice model aimed at providing risk-stratified and convenient care for ABSSSI at the lowest possible cost, while minimizing complications, readmissions, and inappropriate antibiotic use. In doing so, we focus on the care provided by emergency physicians and hospitalists and the transition of management between them for inpatient care, as well as the facilitation of observation or direct-to-outpatient care for suitable patients. <h3>Conclusions</h3> A standard, consistent, and multidisciplinary approach to ABSSSI can streamline care, reduce admissions, support antimicrobial stewardship, and improve clinical and resource consumption outcomes.

We study the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\psi}(2S){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ with initial-state-radiation events produced at the PEP-II asymmetric-energy collider. The data were recorded with the BABAR detector at center-of-mass energies at and near the $\mathrm{\ensuremath{\Upsilon}}(\mathrm{nS})$ ($n=2,3,4$) resonances and correspond to an integrated luminosity of $520\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$. We investigate the $\ensuremath{\psi}(2S){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ mass distribution from 3.95 to $5.95\text{ }\text{ }\mathrm{GeV}/{c}^{2}$, and measure the center-of-mass energy dependence of the associated ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\psi}(2S){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ cross section. The mass distribution exhibits evidence of two resonant structures. A fit to the $\ensuremath{\psi}(2S){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ mass distribution corresponding to the decay mode $\ensuremath{\psi}(2S)\ensuremath{\rightarrow}J/\ensuremath{\psi}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ yields a mass value of $4340\ifmmode\pm\else\textpm\fi{}16\text{ }(\text{stat})\text{ }\ifmmode\pm\else\textpm\fi{}9\text{ }(\text{syst})\text{ }\text{ }\mathrm{MeV}/{c}^{2}\text{ }$ and a width of $94\ifmmode\pm\else\textpm\fi{}32\text{ }(\text{stat})\text{ }\ifmmode\pm\else\textpm\fi{}13\text{ }(\text{syst})\text{ }\text{ }\mathrm{MeV}$ for the first resonance, and for the second a mass value of $4669\ifmmode\pm\else\textpm\fi{}21\text{ }(\text{stat})\text{ }\ifmmode\pm\else\textpm\fi{}3\text{ }(\text{syst})\text{ }\text{ }\mathrm{MeV}/{c}^{2}\text{ }$ and a width of $104\ifmmode\pm\else\textpm\fi{}48\text{ }(\text{stat})\text{ }\ifmmode\pm\else\textpm\fi{}10\text{ }(\text{syst})\text{ }\text{ }\mathrm{MeV}$. In addition, we show the ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ mass distributions for these resonant regions.

We have measured the mass of the Z boson to be 91.11±0.23 GeV/c2, and its width to be 1.61+0.60−0.43 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.62±0.23 GeV, corresponding to 3.8±1.4 neutrino species.Received 24 July 1989DOI:https://doi.org/10.1103/PhysRevLett.63.724©1989 American Physical Society

We have studied exclusive, radiative B meson decays to charmless mesons in 9.7x10(6) B&Bmacr; decays accumulated with the CLEO detector. We measure B(B0-->K(*0)(892)gamma) = (4.55(+0.72)(-0. 68)+/-0.34)x10(-5) and B(B+-->K(*+)(892)gamma) = (3.76(+0.89)(-0. 83)+/-0.28)x10(-5). We have searched for CP asymmetry in B-->K(*)(892)gamma decays and measure A(CP) = +0.08+/-0.13+/-0.03. We report the first observation of B-->K(*)(2)(1430)gamma decays with a branching fraction of (1.66(+0.59)(-0.53)+/-0.13)x10(-5). No evidence for the decays B-->rhogamma and B0-->omegagamma is found and we limit B(B-->(rho/omega)gamma)/B(B-->K(*)(892)gamma)<0.32 at 90% C.L.

In a run with a predominantly $\overline{\ensuremath{\nu}}$ beam we have observed seven dimuon events which show clearly that dimuons are produced by $\overline{\ensuremath{\nu}}$ as well as by $\ensuremath{\nu}$. Using the signature of those events we tentatively identify twelve dimuon events from earlier runs as $\overline{\ensuremath{\nu}}$-induced. The characteristics of the total sample support the explanation that dimuons arise from new hadron production.

Neutrino-induced dimuon events probably involve the production and subsequent decay of one or more real, intermediate particles. The observed properties of dimuon events are shown not to agree with the hypotheses that the intermediate particles are heavy leptons or semiweak vector bosons. This strongly suggests production of new hadrons as the leading explanation of dimuon events. Such new hadrons, decaying weakly, would necessarily possess a new, as yet unidentified, quantum number.

Using a sample of 4994 neutrino events and 2408 antineutrino events we have measured the ratio of antineutrino to neutrino charged-current cross sections up to 100 GeV. Neutrino flux-independent and flux-dependent measurements were carried out with good agreement between the two methods. Below 30 GeV the ratio was found to be 0.38 \ifmmode\pm\else\textpm\fi{} 0.06. The cross-section ratio shows a significant departure from this value above 50 GeV.

We present measured distributions in the scaling variables $x$ and $y$ obtained from the reactions ${\ensuremath{\nu}}_{\ensuremath{\mu}}({\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})+\mathrm{nucleon}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{\ensuremath{-}}({\ensuremath{\mu}}^{+})+\mathrm{hadrons}$ at high energy. The $x$ distributions are consistent with scale invariance. The $x$ and $y$ distributions are used to perform the first test of charge-symmetry invariance in high-energy neutrino interactions, assuming the validity of scale invariance. A possible effective deviation from charge-symmetry invariance is observed, which could be the result of new particle production.

We present a search for the decay ${B}^{+}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}\ensuremath{\nu}$ using $467.8\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected at the $\ensuremath{\Upsilon}(4S)$ resonance with the BABAR detector at the SLAC PEP-II $B$-Factory. We select a sample of events with one completely reconstructed ${B}^{\ensuremath{-}}$ in the hadronic decay mode (${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{(*)0}{X}^{\ensuremath{-}}$ and ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}{X}^{\ensuremath{-}}$). We examine the rest of the event to search for a ${B}^{+}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}\ensuremath{\nu}$ decay. We identify the ${\ensuremath{\tau}}^{+}$ lepton in the following modes: ${\ensuremath{\tau}}^{+}\ensuremath{\rightarrow}{e}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, ${\ensuremath{\tau}}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, ${\ensuremath{\tau}}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\overline{\ensuremath{\nu}}$ and ${\ensuremath{\tau}}^{+}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{+}\overline{\ensuremath{\nu}}$. We find an excess of events with respect to the expected background, which excludes the null signal hypothesis at the level of $3.8\ensuremath{\sigma}$ (including systematic uncertainties) and corresponds to a branching fraction value of $\mathcal{B}({B}^{+}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}\ensuremath{\nu})=({1.83}_{\ensuremath{-}0.49}^{+0.53}(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.24(\mathrm{syst}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$.

We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element $|{V}_{\mathrm{cb}}|$ and the form-factor slope ${\ensuremath{\rho}}^{2}$ in $\overline{B}\ensuremath{\rightarrow}D{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}}$ decays based on $460\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ events recorded at the $\ensuremath{\Upsilon}(4S)$ resonance with the BABAR detector. $\overline{B}\ensuremath{\rightarrow}D{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}}$ decays are selected in events in which a hadronic decay of the second $B$ meson is fully reconstructed. We measure $\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}})/\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}X{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}})=(0.255\ifmmode\pm\else\textpm\fi{}0.009\ifmmode\pm\else\textpm\fi{}0.009)$ and $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}})/\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}X{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}})=(0.230\ifmmode\pm\else\textpm\fi{}0.011\ifmmode\pm\else\textpm\fi{}0.011)$, along with the differential decay distribution in $\overline{B}\ensuremath{\rightarrow}D{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}}$ decays. We then determine $\mathcal{G}(1)|{V}_{\mathrm{cb}}|=(42.3\ifmmode\pm\else\textpm\fi{}1.9\ifmmode\pm\else\textpm\fi{}1.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ and ${\ensuremath{\rho}}^{2}=1.20\ifmmode\pm\else\textpm\fi{}0.09\ifmmode\pm\else\textpm\fi{}0.04$, where $\mathcal{G}(1)$ is the hadronic form factor at the point of zero recoil.

We have performed a search for the eta_b(1S) meson in the radiative decay of the Upsilon(2S) resonance using a sample of 91.6 million Upsilon(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at E_gamma = 609.3 {+4.6} {-4.5} (stat) +/- 1.9 (syst) MeV, corresponding to an eta_b(1S) mass of 9394.2 {+4.8} {-4.9} (stat) +/- 2.0 (syst) MeV/c^2. The branching fraction for the decay Upsilon(2S) --> gamma eta_b(1S) is determined to be [3.9 +/-1.1 (stat) {+1.1} {-0.9} (syst)] x 10^(-4). We find the ratio of branching fractions B[Upsilon(2S) --> gamma eta_b(1S)]/B[Upsilon(3S) --> gamma eta_b(1S)] = 0.82 +/- 0.24 (stat) {+0.20}{-0.19} (syst).

We report here additional positive results of a search for muonless neutrino- and anti-neutrino-induced events using an enriched antineutrino beam and a muon identifier of relatively high geometric detection efficiency. The ratio of muonless to muon event rates is observed to be $R=0.20\ifmmode\pm\else\textpm\fi{}0.05$. We observe no background derived from ordinary neutrino or antineutrino interactions that is capable of explaining the muonless signal.

In a sample of 19 million produced B mesons, we have observed the decays B -> eta K* and improved our previous measurements of B -> eta'K. The branching fractions we measure for these decay modes are BR(B+ -> eta K*+) = (26.4 +9.6-8.2 +- 3.3) x $10^{-6}$, BR(B0 -> eta K*0) = (13.8 +5.5-4.6 +- 1.6) x $10^{-6}$, BR(B+ -> eta' K+) = (80 +10-9 +- 7) x $10^{-6}$ and BR(B0 -> eta' K0) = (89 +18-16 +- 9) x $10^{-6}$. We have searched with comparable sensitivity for related decays and report upper limits for these branching fractions.

Using the CLEO II detector and a sample of 955 000 Υ(4S) decays we have confirmed charmless semileptonic decays of B mesons. In the momentum interval 2.3–2.6 GeV/c we observe an excess of 107±15±11 leptons, which we attribute to b→ulν. This result yields a model-dependent range of values for ‖Vub/Vcb‖ that is lower than has been obtained in previous studies. For the inclusive spectator model of Altarelli et al. we find ‖Vub/Vcb‖=0.076±0.008. Models that describe b→ulν with a limited set of exclusive final states give ‖Vub/Vcb‖=0.06-0.10.Received 7 September 1993DOI:https://doi.org/10.1103/PhysRevLett.71.4111©1993 American Physical Society

We present a search for the decay $\B^+ \to \ell^+ \nu_{\ell} (\ell = \tau, \mu, \mathrm{or} e)$ in $(458.9 \pm 5.1) \times 10^{6}$ $\Upsilon(4S)$ decays recorded with the Babar detector at the SLAC PEP-II $B$-Factory. A sample of events with one reconstructed exclusive semi-leptonic B decay ($B^{-}\to D^{0} \ell^{-}\bar{\nu} X$) is selected, and in the recoil a search for $\B^+ \to \ell^+ \nu_{\ell}$ signal is performed. The $\tau$ is identified in the following channels: $\tau^+ \to e^+ \nu_e \overline{\nu}_\tau$, $\tau^+ \to \mu^+ \nu_{\mu} \overline{\nu}_{\tau}$, $\tau^+ \to \pi^+ \overline{\nu}_{\tau}$, and $\tau^+ \to \pi^+ \pi^{0} \overline{\nu}_{\tau}$. The analysis strategy and the statistical procedure is set up for the branching fraction extraction or upper limit determination. We determine from the dataset a preliminary measurement of $\mathcal{B}(\B^+ \to \tau^+ \nu_{\tau}) = (1.8 \pm 0.8 \pm 0.1) \times 10^{-4}$, which excludes zero at $2.4 \sigma$, and $f_{B} = 230 \pm 57 \mev $. Combination with the hadronically tagged measurement yields $\mathcal{B}(\B^+ \to \tau^+ \nu_{\tau}) = (1.8 \pm 0.6) \times 10^{-4}$. We also set preliminary limits on the branching fractions at $\mathcal{B}(\B^+ \to e^+ \nu_{e}) < 7.7 \times 10^{-6} (\textrm{90% C.L.})$, $\mathcal{B}(\B^+ \to \mu^+ \nu_{\mu}) < 11 \times 10^{-6} (\textrm{90% C.L.})$, and $\mathcal{B}(\B^+ \to \tau^+ \nu_{\tau}) < 3.2 \times 10^{-4} (\textrm{90% C.L.})$.

Relative rates for deep inelastic neutrino and antineutrino scattering without a finalstate muon have been measured. For neutrinos the result is ${R}^{\ensuremath{\nu}}=\frac{\ensuremath{\sigma}({\ensuremath{\nu}}_{\ensuremath{\mu}}+\mathrm{nucleon}\ensuremath{\rightarrow}{\ensuremath{\nu}}_{\ensuremath{\mu}}+\mathrm{hadrons})}{\ensuremath{\sigma}({\ensuremath{\nu}}_{\ensuremath{\mu}}+\mathrm{nucleon}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{\ensuremath{-}}+\mathrm{hadrons})}=0.11\ifmmode\pm\else\textpm\fi{}0.05$. The corresponding ratio for antineutrinos is ${R}^{\overline{\ensuremath{\nu}}}=0.32\ifmmode\pm\else\textpm\fi{}0.09$.

Measurements of ${R}^{\ensuremath{\nu}}$ and ${R}^{\overline{\ensuremath{\nu}}}$, the ratios of neutral current to charged current $\ensuremath{\nu}$ and $\overline{\ensuremath{\nu}}$ cross sections, yield neutral current rates for $\ensuremath{\nu}$ and $\overline{\ensuremath{\nu}}$ that are consistent with a pure $V\ensuremath{-}A$ interaction but 3 standard deviations from pure $V$ or pure $A$, indicating the presence of parity nonconservation in the weak neutral current.

The e+ e- --> p anti-p cross section and the proton magnetic form factor have been measured in the center-of-mass energy range from 3.0 to 6.5 GeV using the initial-state-radiation technique with an undetected photon. This is the first measurement of the form factor at energies higher than 4.5 GeV. The analysis is based on 469 fb-1 of integrated luminosity collected with the BABAR detector at the PEP-II collider at e+e- center-of-mass energies near 10.6 GeV. The branching fractions for the decays J/psi --> p anti-p and psi(2S) --> p anti-p have also been measured.

A search for the neutrinoless, lepton-flavor violating decay of the τ lepton into three charged leptons has been performed using an integrated luminosity of 468 fb−1 collected with the BABAR detector at the PEP-II collider. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (1.8–3.3)×10−8 at 90% confidence level.Received 24 February 2010DOI:https://doi.org/10.1103/PhysRevD.81.111101©2010 American Physical Society

The dependence of the neutrino total cross section ${\ensuremath{\sigma}}_{\ensuremath{\nu}}$ on neutrino energy has been measured up to 160 GeV. The data are consistent with a linear dependence with slope (0.58 \ifmmode\pm\else\textpm\fi{} 0.25) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}38}$ ${\mathrm{cm}}^{2}$/GeV. The ratio of the antineutrino to the neutrino total cross section $\frac{{\ensuremath{\sigma}}_{\overline{\ensuremath{\nu}}}}{{\ensuremath{\sigma}}_{\ensuremath{\nu}}}$ has been found to be approximately constant up to 70 GeV at a value which is consistent with the numerical value of $\frac{1}{3}$ expected for the scattering of neutrinos and antineutrinos by relativistic pointlike spin-\textonehalf{} fermions.

Inclusive production cross sections of $\pi^\pm$, $K^\pm$ and $p\bar{p}$ per hadronic $e^+e^-$ annihilation event in $e^+e^-$ are measured at a center-of-mass energy of 10.54 GeV, using a relatively small sample of very high quality data from the BaBar experiment at the PEP-II $B$-factory at the SLAC National Accelerator Laboratory. The drift chamber and Cherenkov detector provide clean samples of identified $\pi^\pm$, $K^\pm$ and $p\bar{p}$ over a wide range of momenta. Since the center-of-mass energy is below the threshold to produce a $B\bar{B}$ pair, with $B$ a bottom-quark meson, these data represent a pure $e^+e^- \rightarrow q\bar{q}$ sample with four quark flavors, and are used to test QCD predictions and hadronization models. Combined with measurements at other energies, in particular at the $Z^0$ resonance, they also provide precise constraints on the scaling properties of the hadronization process over a wide energy range.

We search for di-muon decays of a low-mass Higgs boson (A^0) produced in radiative \Upsilon(1S) decays. The \Upsilon(1S) sample is selected by tagging the pion pair in the \Upsilon(2S, 3S) \to \pi^+ \pi^- \Upsilon(1S) transitions, using a data sample of 92.8 \times 10^6 \Upsilon(2S) and 116.8 \times 10^6 \Upsilon(3S) events collected by the \babar\ detector. We find no evidence for A^0 production and set 90% confidence level upper limits on the product branching fraction \mathcal{B} (\Upsilon(1S) \to \gamma A^0) \times \mathcal{B} (A^0 \to \mumu) in the range of (0.28 - 9.7) \times 10^{-6} for 0.212 \le m_{A^0} \le 9.20 GeV/c^2. The results are combined with our previous measurements of \Upsilon(2S,3S) \to \gamma A^0, A^0 \to \mumu to set limits on the effective coupling of the \b-quark to the A^0.

We study the rare B meson decays B{+-,0} --> J/\psi\ K^+ K^- K{+-,0}, B{+-,0} --> J/\psi\ \phi\ K{+-,0}, and search for B0 --> J/\psi\ \phi, using 469 million BBbar events collected at the Upsilon(4S) resonance with the BABAR detector at the PEP-II e+e- asymmetric-energy collider. We present new measurements of branching fractions and a study of the J/\psi\phi mass distribution in search of new charmonium-like states. In addition, we search for the decay B0 --> J/\psi\ \phi, and find no evidence of a signal.

We report results of searches for charmless hadronic B meson decays to pseudoscalar( pi(+/-), K+/-, pi(0), or K(0)(S))-vector( rho, K(*), or omega) final states. By using 9.7x10(6) BB pairs collected with the CLEO detector, we report the first observation of B(-)--->pi(-)rho(0), B(0)-->pi(+/-)rho(-/+), and B(-)-->pi(-)omega, which are expected to be dominated by hadronic b-->u transitions. The measured branching fractions are (10.4(+3.3)(-3.4)+/-2.1)x10(-6), (27.6(+8.4)(-7.4)+/-4.2)x10(-6), and (11.3(+3.3)(-2.9)+/-1. 4)x10(-6), respectively. Branching fraction upper limits are set for all of the other decay modes investigated.

We have studied charmless hadronic decays of $B$ mesons into two-body final states with kaons and pions and observe three new processes with the following branching fractions: $B(B\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}({4.3}_{\ensuremath{-}1.4}^{+1.6}\ifmmode\pm\else\textpm\fi{}0.5)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $B(B\ensuremath{\rightarrow}{K}^{0}{\ensuremath{\pi}}^{0})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}({14.6}_{\ensuremath{-}5.1\ensuremath{-}3.3}^{+5.9+2.4})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, and $B(B\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{0})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}({11.6}_{\ensuremath{-}2.7\ensuremath{-}1.3}^{+3.0+1.4})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$. We also update our previous measurements for the decays $B\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ensuremath{\mp}}$ and ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{0}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$.

We have measured the B0B¯0 mixing probability, χd, using a sample of 965 000 BB¯ pairs from Υ(4S) decays. Counting dilepton events, we find χd=0.157±0.016±0.018−0.021+0.028. Using tagged B0 events, we find χd=0.149±0.023±0.019±0.010. The first (second) error is statistical (systematic). The third error reflects a ±15% uncertainty in the assumption, made in both cases, that charged and neutral B pairs contribute equally to dilepton events. We also obtain a limit on the CP impurity in the Bd0 system, ‖Re(εB0)‖<0.045 at 90% C.L.Received 29 April 1993DOI:https://doi.org/10.1103/PhysRevLett.71.1680©1993 American Physical Society

We present a Dalitz plot analysis of charmless B+- decays to the final state pi+-pi+-pi-+ using a sample of (465+-5)x10^-6 BBbar pairs collected by the BABAR experiment at \sqrt{s} = 10.58 GeV. We measure the branching fractions BF(B+- --> pi+-pi+-pi-+) = (15.2+-0.6+-1.2+-0.4)x10^-6, BF(B+- --> rho0(770)pi+-) = (8.1+-0.7+-1.2^{+0.4}_{-1.1})x10^-6, BF(B+- --> f2(1270)pi+-) = (1.57+-0.42+-0.16^{+0.53}_{-0.19})x10^-6, and BF(B+- --> pi+-pi+-pi-+ nonresonant) = (5.3+-0.7+-0.6^{+1.1}_{-0.5})x10^-6, where the uncertainties are statistical, systematic, and model-dependent, respectively. Measurements of branching fractions for the modes B+- --> rho0(1450)pi+- and B+- --> f0(1370)pi+- are also presented. We observe no significant direct CP asymmetries for the above modes, and there is no evidence for the decays B+- --> chiC0 pi+-, or B+- --> chiC2 pi+-.

We search for a light Higgs boson, $A^0$, in the radiative decay $\Upsilon(3S)\to\gamma A^0$, $A^0\to\tau^+\tau^-$, $\tau^+\to e^+\nu_e \bar{\nu}_{\tau}$ or $\tau^+\to \mu^+ \nu_{\mu} \bar{\nu}_{\tau}$. The data sample contains 122 million $\Upsilon(3S)$ events recorded with the \babar detector. We find no evidence for a narrow structure in the studied $\tau^+\tau^-$ invariant mass region of $4.03<m_{\tau^+\tau^-}<10.10$ \gevcc. We exclude at the 90% confidence level (C.L.) a low mass Higgs decaying to $\tau^+\tau^-$ with a product branching fraction ${\cal {B}}(\Upsilon(3S)\to\gamma A^0)\times {\cal {B}}(A^0\to\tau^+\tau^-)$ $>(1.5-16)\times 10^{-5}$ across the $m_{\tau^+\tau^-}$ range. We also set a 90% C.L. upper limit on the $\tau^+\tau^-$-decay of the $\eta_b$ at ${\mathcal{B}}(\eta_b\to \tau^+\tau^-)<8%$.

Identification of muons in hadronic events from ${e}^{+}{e}^{\ensuremath{-}}$ annihilation observed in the MAC detector at the storage ring PEP provides flavor tagging of heavy primary quarks. A sample enriched in events from $b\overline{b}$ production is obtained and the $b$-quark fragmentation function is inferred from the momentum spectrum of the muons. The $b$ quark is found to fragment predominantly with high values of $z$, with $〈{z}_{b}〉=0.8\ifmmode\pm\else\textpm\fi{}0.1$, and to have an over-all semimuonic branching fraction of (${15.5}_{\ensuremath{-}2.9}^{+5.4}$)%.

We report on a Dalitz plot analysis of ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}}$ decays, based on a sample of about $383\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $\ensuremath{\Upsilon}(4\mathrm{S})\ensuremath{\rightarrow}B\overline{B}$ decays collected with the BABAR detector at the PEP-II asymmetric-energy $B$ Factory at SLAC. We find the total branching fraction of the three-body decay: $\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}})=(1.08\ifmmode\pm\else\textpm\fi{}0.03\ifmmode\pm\else\textpm\fi{}0.05)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$. We observe the established ${D}_{2}^{*0}$ and confirm the existence of ${D}_{0}^{*0}$ in their decays to ${D}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, where the ${D}_{2}^{*0}$ and ${D}_{0}^{*0}$ are the ${2}^{+}$ and ${0}^{+}c\overline{u}$ $P$-wave states, respectively. We measure the masses and widths of ${D}_{2}^{*0}$ and ${D}_{0}^{*0}$ to be: ${m}_{{D}_{2}^{*0}}=(2460.4\ifmmode\pm\else\textpm\fi{}1.2\ifmmode\pm\else\textpm\fi{}1.2\ifmmode\pm\else\textpm\fi{}1.9)\text{ }\text{ }\mathrm{MeV}/{c}^{2}$, ${\ensuremath{\Gamma}}_{{D}_{2}^{*0}}=(41.8\ifmmode\pm\else\textpm\fi{}2.5\ifmmode\pm\else\textpm\fi{}2.1\ifmmode\pm\else\textpm\fi{}2.0)\text{ }\text{ }\mathrm{MeV}$, ${m}_{{D}_{0}^{*0}}=(2297\ifmmode\pm\else\textpm\fi{}8\ifmmode\pm\else\textpm\fi{}5\ifmmode\pm\else\textpm\fi{}19)\text{ }\text{ }\mathrm{MeV}/{c}^{2}$, and ${\ensuremath{\Gamma}}_{{D}_{0}^{*0}}=(273\ifmmode\pm\else\textpm\fi{}12\ifmmode\pm\else\textpm\fi{}17\ifmmode\pm\else\textpm\fi{}45)\text{ }\text{ }\mathrm{MeV}$. The stated errors reflect the statistical and systematic uncertainties, and the uncertainty related to the assumed composition of signal events and the theoretical model.

We search for hadronic decays of a light Higgs boson (A(0)) produced in radiative decays of an Υ(2S) or Υ(3S) meson, Υ→γA(0). The data have been recorded by the BABAR experiment at the Υ(3S) and Υ(2S) center-of-mass energies and include (121.3±1.2)×10(6) Υ(3S) and (98.3±0.9)×10(6) Υ(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions B(Υ(nS)→γA(0))B(A(0)→hadrons) (n=2 or 3) that range from 1×10(-6) for an A(0) mass of 0.3 GeV/c(2) to 8×10(-5) at 7 GeV/c(2).

The measured distributions in invariant mass $W$ of the recoiling hadron systems in neutrino- and antineutrino-nucleon inelastic collisions are observed to be significantly different after taking into account the opposite helicities of neutrinos and antineutrinos. These distributions indicate the onset of a new phenomenon in the antineutrino data beginning at an incident energy of about 30 GeV, which appears as an excess of events with $W&gt;4$ GeV/${\mathit{c}}^{2}$.

We present a search for the lepton flavor violating decay modes B+/- to h+/- tau l (h= K,pi; l= e,mu) using the BaBar data sample, which corresponds to 472 million BBbar pairs. The search uses events where one B meson is fully reconstructed in one of several hadronic final states. Using the momenta of the reconstructed B, h, and l candidates, we are able to fully determine the tau four-momentum. The resulting tau candidate mass is our main discriminant against combinatorial background. We see no evidence for B+/- to h+/- tau l decays and set a 90% confidence level upper limit on each branching fraction at the level of a few times 10^-5.

Based on a sample of 500 million ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}c\overline{c}$ events recorded by the BABAR detector at c.m. energies of close to 10.6 GeV, we report on a study of the decay ${D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{\ensuremath{\nu}}_{e}$. We measure the ratio of branching fractions, ${R}_{D}=\mathcal{B}({D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{\ensuremath{\nu}}_{e})/\mathcal{B}({D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+})=0.0713\ifmmode\pm\else\textpm\fi{}0.001{7}_{\text{stat}}\ifmmode\pm\else\textpm\fi{}0.002{4}_{\text{syst}}$, and use the present world average for $\mathcal{B}({D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+})$ to obtain $\mathcal{B}({D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{\ensuremath{\nu}}_{e})=(2.770\ifmmode\pm\else\textpm\fi{}0.06{8}_{\text{stat}}\ifmmode\pm\else\textpm\fi{}0.09{2}_{\text{syst}}\ifmmode\pm\else\textpm\fi{}0.03{7}_{\text{ext}})\ifmmode\times\else\texttimes\fi{}1{0}^{\ensuremath{-}3}$ where the third error accounts for the uncertainty on the branching fraction for the reference channel. The measured dependence of the differential branching fraction on ${q}^{2}$, the four-momentum transfer squared between the $D$ and the $\ensuremath{\pi}$ meson, is compared to various theoretical predictions for the hadronic form factor, ${f}_{+,D}^{\ensuremath{\pi}}({q}^{2})$, and the normalization $|{V}_{cd}|\ifmmode\times\else\texttimes\fi{}{f}_{+,D}^{\ensuremath{\pi}}({q}^{2}=0)=0.1374\ifmmode\pm\else\textpm\fi{}\phantom{\rule{0ex}{0ex}}0.003{8}_{\text{stat}}\ifmmode\pm\else\textpm\fi{}0.002{2}_{\text{syst}}\ifmmode\pm\else\textpm\fi{}0.000{9}_{\text{ext}}$. is extracted from a fit to data. Using the most recent LQCD prediction of ${f}_{+,D}^{\ensuremath{\pi}}({q}^{2}=0)=0.666\ifmmode\pm\else\textpm\fi{}0.029$, we obtain $|{V}_{cd}|=0.206\ifmmode\pm\else\textpm\fi{}0.00{7}_{\text{exp}}\ifmmode\pm\else\textpm\fi{}0.00{9}_{\mathrm{LQCD}}$. Assuming, instead, $|{V}_{cd}|=|{V}_{us}|=0.2252\ifmmode\pm\else\textpm\fi{}0.0009$, we obtain ${f}_{+,D}^{\ensuremath{\pi}}({q}^{2}=0)=0.610\ifmmode\pm\else\textpm\fi{}0.02{0}_{\text{exp}}\ifmmode\pm\else\textpm\fi{}0.00{5}_{\text{ext}}$. The ${q}^{2}$ dependence of ${f}_{+,D}^{\ensuremath{\pi}}({q}^{2})$ is compared to a variety of multipole parametrizations. This information is applied to ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{\ensuremath{\nu}}_{e}$ decays and, combined with an earlier ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{\ensuremath{\nu}}_{e}$ measurement by BABAR, is used to derive estimates of $|{V}_{ub}|$.

We have used the CLEO-II detector at the Cornell Electron Storage Ringe (CESR) to study the inclusive production of charmonium mesons in a sample of 2.15 million BB¯ events. We find inclusive branching fractions of (1.12±0.04±0.06)% for B→J/ψX, (0.34±0.04±0.03)% for B→ψ′X, and (0.40±0.06±0.04)% for B→χc1X. We also find some evidence for the inclusive production of χc2, and set an upper limit for the branching fraction of the inclusive decay B→ηcX of 0.9% at 90% confidence level. Momentum spectra for inclusive J/ψ, ψ′, and χc1 production are presented. These measurements are compared to theoretical calculations.Received 13 December 1994DOI:https://doi.org/10.1103/PhysRevD.52.2661©1995 American Physical Society

We have studied two-body charmless hadronic decays of B mesons into the final states $\pi\pi$, $K \pi$, and $KK$. Using 3.3 million $B\bar{B}$ pairs collected with the CLEO-II detector, we have made the first observation of the decays $B^0\to K^+\pi^-$, $B^+\to K^0\pi^+$, and the sum of $B^+ \to \pi^+\pi^0$ and $B^+ \to K^+\pi^0$ decays (an average over charge-conjugate states is always implied). We place upper limits on branching fractions for the remaining decay modes.

We perform a time-dependent amplitude analysis of $B^0 \to K^0_S\pi^+\pi^-$ decays to extract the CP violation parameters of $f_0(980) K^0_S$ and $\rho^0(770) K^0_S$ and the direct CP asymmetry of $K^{*+}(892) \pi^-$. The results are obtained from a data sample of $(383 \pm 3) \times 10^6$ $B\bar{B}$ decays, collected with the BABAR detector at the PEP-II asymmetric-energy $B$ factory at SLAC. We find two solutions, with an equivalent goodness-of-fit. Including systematic and Dalitz plot model uncertainties, the combined confidence interval for values of the CP parameter $\beta_{eff}$ in $B^0$ decays to $f_0(980) K^0_S$ is $18^o < \beta_{eff} < 76^o$ at 95% confidence level (C.L). CP conservation in $B^0$ decays to $f_0(980) K^0_S$ is excluded at $3.5\sigma$ including systematic uncertainties. For $B^0$ decays to $\rho^0(770) K^0_S$, the combined confidence interval is $-9^o < \beta_{eff} < 57^o$ at 95% C.L. In decays to $K^{*+}(892) \pi^-$ we measure the direct CP asymmetry to be $A_{CP}=-0.20 \pm 0.10 \pm 0.01 \pm 0.02$. The measured phase difference (including $B^0\bar{B}^0$ mixing) between decay amplitudes of $B^0 \to K^{*+}(892) \pi^-$ and $\bar{B}^0 \to K^{*-}(892) \pi^+$, excludes the interval $-137^o < \Delta\Phi(K^{*+}(892) \pi^-) < -5^o$ at 95% C.L.

A Dalitz plot analysis of approximately 13 000 D+s decays to π+π−π+ has been performed. The analysis uses a 384 fb−1 data sample recorded by the BABAR detector at the PEP-II asymmetric-energy e+e− storage ring running at center of mass energies near 10.6 GeV. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio of branching fractions is performed: B(D+s→π+π−π+)/B(D+s→K+K−π+)=0.199±0.004±0.009. Using a model-independent partial wave analysis, the amplitude and phase of the S wave have been measured.Received 9 December 2008DOI:https://doi.org/10.1103/PhysRevD.79.032003©2009 American Physical Society

We measure the rate of D0−¯¯¯D0 mixing with the observable yCP=(τKπ/τKK)−1, where τKK and τKπ are, respectively, the mean lifetimes of CP-even D0→K+K− and CP-mixed D0→K−π+ decays, using a data sample of 384 fb−1 collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B Factory. From a sample of D0 and ¯¯¯D0 decays where the initial flavor of the decaying meson is not determined, we obtain yCP=[1.12±0.26(stat)±0.22(syst)]%, which excludes the no-mixing hypothesis at 3.3σ, including both statistical and systematic uncertainties. This result is in good agreement with a previous BABAR measurement of yCP obtained from a sample of D*+→D0π+ events, where the D0 decays to K−π+, K+K−, and π+π−, which is disjoint with the untagged D0 events used here. Combining the two results taking into account statistical and systematic uncertainties, where the systematic uncertainties are assumed to be 100% correlated, we find yCP=[1.16±0.22(stat)±0.18(syst)]%, which excludes the no-mixing hypothesis at 4.1σ.Received 7 August 2009DOI:https://doi.org/10.1103/PhysRevD.80.071103©2009 American Physical Society

Presented here are preliminary results of two short runs with a broad-band neutrino-antineutrino beam at National Accelerator Laboratory incident on about 120 tons of target which is part of a detector consisting of an ionization calorimeter and a muon magnetic spectrometer. These results include (i) the observed distribution in transverse muon momentum, $\frac{\mathrm{dN}}{d{p}_{\ensuremath{\mu}}}$, (ii) the average neutrino cross section at a mean neutrino energy of roughly 30 GeV, and (iii) the ratio of the antineutrino to the neutrino total cross section at a mean neutrino energy of 40 GeV.

We report on analyses of tau lepton decays $\tau^- \to \eta K^- \nu_{\tau}$ and $\tau^- \to \eta \pi^- \nu_{\tau}$, with $\eta \to \pi^+ \pi^- \pi^0$, using 470 fb$^{-1}$ of data from the Babar experiment at PEP-II, collected at center-of-mass energies at and near the $\Upsilon(4S)$ resonance. We measure the branching fraction for the $\tau^- \to \eta K^- \nu_{\tau}$ decay mode, $\Br(\tau^- \to \eta K^- \nu_{\tau}) = (1.42\pm0.11\text{(stat)}\pm0.07\text{(syst)})\times10^{-4}$, and report a 95% confidence level upper limit for the second-class current process $\tau^- \to \eta \pi^- \nu_{\tau}$, $\Br(\tau^- \to \eta \pi^- \nu_{\tau}) < 9.9\times10^{-5}$.

We report a search for CP violation in the decay \tau- -> \pi - \K^0_S (>= 0 \pi 0) \nu_\tau\ using a dataset of 437 million \tau\ lepton pairs, corresponding to an integrated luminosity of 476 fb^{-1}, collected with the BABAR detector at the PEP-II asymmetric energy e+e- storage rings. The CP-violating decay-rate asymmetry is determined to be (-0.45 +/- 0.24 +/- 0.11)%, approximately three standard deviations from the Standard Model prediction of (0.33 +/- 0.01)%.

We report a comparison of the Dalitz-plot distributions of 1.6 million ${\ensuremath{\tau}}^{+}$ decays (${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$) and an equal number of ${\ensuremath{\tau}}^{\ensuremath{-}}$ decays. No significant asymmetry has been found in any region of the plot. In terms of the difference in the slope parameters ${a}^{+}$ and ${a}^{\ensuremath{-}}$ for the odd-pion c.m.-energy spectra, the asymmetry is $\ensuremath{\Delta}=\frac{({a}^{+}\ensuremath{-}{a}^{\ensuremath{-}})}{({a}^{+}+{a}^{\ensuremath{-}})}=\ensuremath{-}0.0070\ifmmode\pm\else\textpm\fi{}0.0053$. We also present a preliminary result for the slope parameter itself: $a=0.283\ifmmode\pm\else\textpm\fi{}0.005$. New measurements of the ${\ensuremath{\tau}}^{\ifmmode\pm\else\textpm\fi{}}$ decay rates and their difference confirm previous results.

We present a search for a neutral, long-lived particle L that is produced in e+ e- collisions and decays at a significant distance from the e+ e- interaction point into various flavor combinations of two oppositely charged tracks. The analysis uses an e+ e- data sample with a luminosity of 489.1 fb(-1) collected by the BABAR detector at the ϒ(4S), ϒ(3S), and ϒ(2S) resonances and just below the ϒ(4S). Fitting the two-track mass distribution in search of a signal peak, we do not observe a significant signal, and set 90% confidence level upper limits on the product of the L production cross section, branching fraction, and reconstruction efficiency for six possible two-body L decay modes as a function of the L mass. The efficiency is given for each final state as a function of the mass, lifetime, and transverse momentum of the candidate, allowing application of the upper limits to any production model. In addition, upper limits are provided on the branching fraction B(B→XsL), where Xs is a strange hadronic system.

Diabetes is a common condition, afflicting more than 20 % of the American population over the age of 60 years. Patients with diabetes, particularly those with lower socioeconomic status or limited access to primary care, frequently seek care in hospital emergency departments. Emergency medicine physicians and hospitalists should coordinate care to improve glycemic control while maintaining safety. This may help to overcome clinical inertia and improve long term clinical outcomes for patients who seek acute medical care for diabetes.

We report on a search for eleven lepton-number violating processes B+ -> X- l+ l'+ with X- = K-, pi-, rho-, K*- or D- and l+/l'+ = e+ or mu+, using a sample of 471+/-3 million BBbar events collected with the BaBar detector at the PEP-II e+e- collider at the SLAC National Accelerator Laboratory. We find no evidence for any of these modes and place 90% confidence level upper limits on their branching fractions in the range $(1.5-26)\times 10^{-7}$.

Using the CLEO II detector, we have measured the branching fractions for $\ensuremath{\Upsilon}(3S)\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi}\ensuremath{\Upsilon}(1S)$, $\ensuremath{\Upsilon}(3S)\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi}\ensuremath{\Upsilon}(2S)$, and the cascade $\ensuremath{\Upsilon}(3S)\ensuremath{\rightarrow}\ensuremath{\Upsilon}(2S)+X$, $\ensuremath{\Upsilon}(2S)\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\Upsilon}(1S)$, analyzing the exclusive mode where the daughter $\ensuremath{\Upsilon}$ state decays to a ${e}^{+}{e}^{\ensuremath{-}}$ or ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ pair, as well as the inclusive ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ transitions where the final $\ensuremath{\Upsilon}$ state decays into hadrons. Properties of the $\ensuremath{\pi}\ensuremath{\pi}$ system are analyzed. Searches for the cascade decay $\ensuremath{\Upsilon}(3S)\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{h}_{b}$, ${h}_{b}\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\eta}}_{b}$ and $\ensuremath{\Upsilon}(3S)\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{h}_{b}$ were also performed.

We report results from a search for the decays ${\mathit{B}}^{0}$\ensuremath{\rightarrow}${\mathrm{\ensuremath{\pi}}}^{+}$${\mathrm{\ensuremath{\pi}}}^{\mathrm{\ensuremath{-}}}$, ${\mathit{B}}^{0}$\ensuremath{\rightarrow}${\mathit{K}}^{+}$${\mathrm{\ensuremath{\pi}}}^{\mathrm{\ensuremath{-}}}$, and ${\mathit{B}}^{0}$\ensuremath{\rightarrow}${\mathit{K}}^{+}$${\mathit{K}}^{\mathrm{\ensuremath{-}}}$. We find 90% confidence level upper limits on the branching fractions, ${\mathit{B}}_{\mathrm{\ensuremath{\pi}}\mathrm{\ensuremath{\pi}}}$2.9\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$, ${\mathit{B}}_{\mathit{K}\mathrm{\ensuremath{\pi}}}$2.6\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$, and ${\mathit{B}}_{\mathit{K}\mathit{K}}$0.7\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$. While there is no statistically significant signal in the individual modes, the sum of ${\mathit{B}}_{\mathrm{\ensuremath{\pi}}\mathrm{\ensuremath{\pi}}}$ and ${\mathit{B}}_{\mathit{K}\mathrm{\ensuremath{\pi}}}$ exceeds zero with a significance of more than 4 standard deviations, indicating that we have observed charmless hadronic B decays.

The decay ${\mathrm{\ensuremath{\tau}}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\ensuremath{\nu}}_{\mathrm{\ensuremath{\tau}}}$${\mathrm{\ensuremath{\pi}}}^{\mathrm{\ensuremath{-}}}$${\mathrm{\ensuremath{\pi}}}^{0}$\ensuremath{\eta} has been observed for the first time using the CLEO-II detector at the Cornell Electron Storage Ring. The measured branching ratio (0.17\ifmmode\pm\else\textpm\fi{}0.02\ifmmode\pm\else\textpm\fi{}0.02)%, agrees with the CVC (conserved vector current) prediction based on ${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\mathrm{\ensuremath{\pi}}}^{+}$${\mathrm{\ensuremath{\pi}}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\eta} data. Upper limits on the branching ratios for other \ensuremath{\tau} decays to final states including \ensuremath{\eta} mesons are improved by an order of magnitude compared to previous measurements.

Precise results are reported for the $\ensuremath{\tau}$-lepton lifetime and several $\ensuremath{\tau}$ branching ratios obtained with the MAC detector operating at PEP at $\sqrt{s}=29$ GeV. We find ${\ensuremath{\tau}}_{\ensuremath{\tau}}=(3.15\ifmmode\pm\else\textpm\fi{}0.36\ifmmode\pm\else\textpm\fi{}0.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}$ sec. Results for the topological branching ratios ${B}_{1}$, ${B}_{3}$, ${B}_{5}$ ($\ensuremath{\tau}$ decaying into 1, 3, 5 charged particles) are ${B}_{3}\ensuremath{\equiv}1\ensuremath{-}{B}_{1}=0.133\ifmmode\pm\else\textpm\fi{}0.003\ifmmode\pm\else\textpm\fi{}0.006$ and ${B}_{5}&lt;0.0017$ at the 95% confidence level. The fraction of all three-prong decays unaccompanied by ${\ensuremath{\pi}}^{0}'\mathrm{s}$ is found to be 0.61\ifmmode\pm\else\textpm\fi{}0.03\ifmmode\pm\else\textpm\fi{}0.05.

We describe the performance of a large-volume liquid-scintillator calorimeter which has been used to measure the total energy of hadrons produced by interactions of neutrinos with nucleons. The resolution of the calorimeter is about 12% rms for incident pions over the energy range 20–150 GeV, and about 15% for neutrino-induced hadron systems in the chosen fiducial volume after corrections for imperfect energy containment.

Using the entire sample of 467 million Y(4S) --> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy B factory at SLAC, we perform a "GLW" analysis of B+- --> D K+- decays, using decay modes in which the neutral D meson decays to either CP-eigenstates or non-CP-eigenstates. We measure the partial decay rate charge asymmetries for CP-even and CP-odd D final states to be A_CP+ = 0.25+-0.06+-0.02 and A_CP- = -0.09+-0.07+-0.02, respectively, where the first error is the statistical and the second is the systematic uncertainty. The parameter A_CP+ is different from zero with a significance of 3.6 standard deviations, constituting evidence for direct CP violation. We also measure the ratios of the charged-averaged B partial decay rates in CP and non-CP decays, R_CP+ = 1.18+-0.09+-0.05 and R_CP- = 1.07+-0.08+-0.04. We infer frequentist confidence intervals for the angle gamma of the (db) unitarity triangle, for the strong phase difference delta_B, and for the amplitude ratio r_B, which are related to the B- --> DK- decay amplitude by r_Be^{i(delta_B-gamma)} = A(B- --> anti-D0 K^-)/A(B- --> D0 K-). Including statistical and systematic uncertainties, we obtain 0.24<r_B<0.45 (0.06<r_B<0.51) and, modulo 180 degrees, 11.3 degrees < gamma < 22.7 degrees or 80.9 degrees < gamma < 99.1 degrees or 157.3 degrees < gamma < 168.7 degrees (7.0 degrees < gamma < 173.0 degrees) at the 68% (95%) confidence level.

We search for CP violation in a sample of 4.7×104 Cabibbo suppressed D0→K+K−π+π− decays. We use 470 fb−1 of data recorded by the BABAR detector at the PEP-II asymmetric-energy e+e− storage rings running at center-of-mass energies near 10.6 GeV. CP violation is searched for in the difference between the T-odd asymmetries, obtained using triple product correlations, measured for D0 and ¯¯¯D0 decays. The measured CP violation parameter is AT=(1.0±5.1stat±4.4syst)×10−3.Received 17 March 2010DOI:https://doi.org/10.1103/PhysRevD.81.111103©2010 American Physical Society

Using a sample of 471 million BBbar events collected with the BaBar detector, we study the sum of seven exclusive final states B->X_s(d) gamma, where X_s(d) is a strange (non-strange) hadronic system with a mass of up to 2.0GeV/c^2. After correcting for unobserved decay modes, we obtain a branching fraction for b->d gamma of (9.2 +/- 2.0(stat.) +/- 2.3(syst.))x10^-6 in this mass range, and a branching fraction for b->s gamma of (23.0 +/- 0.8(stat.) +/- 3.0(syst.))x10^-5 in the same mass range. We find BF(b->dgamma) / BF(b->sgamma) = 0.040 +/- 0.009(stat.) +/- 0.010(syst.), from which we determine |V_td/V_ts|=0.199 +/- 0.022(stat.) +/- 0.024(syst.) +/- 0.002(th.).

We study the processes $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}\ensuremath{\eta}$ and $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ using a data sample of $519\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider at center-of-mass energies at and near the $\mathit{\ensuremath{\Upsilon}}(nS)$ ($n=2,3,4$) resonances. We observe ${\ensuremath{\eta}}_{c}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ and ${\ensuremath{\eta}}_{c}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}\ensuremath{\eta}$ decays, measure their relative branching fraction, and perform a Dalitz plot analysis for each decay. We observe the ${K}_{0}^{*}(1430)\ensuremath{\rightarrow}K\ensuremath{\eta}$ decay and measure its branching fraction relative to the $K\ensuremath{\pi}$ decay mode to be $\mathcal{R}({K}_{0}^{*}(1430))=\frac{\mathcal{B}({K}_{0}^{*}(1430)\ensuremath{\rightarrow}K\ensuremath{\eta})}{\mathcal{B}({K}_{0}^{*}(1430)\ensuremath{\rightarrow}K\ensuremath{\pi})}=0.092\ifmmode\pm\else\textpm\fi{}0.02{5}_{\ensuremath{-}0.025}^{+0.010}$. The ${\ensuremath{\eta}}_{c}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}\ensuremath{\eta}$ and ${K}_{0}^{*}(1430)\ensuremath{\rightarrow}K\ensuremath{\eta}$ results correspond to the first observations of these channels. The data also show evidence for ${\ensuremath{\eta}}_{c}(2S)\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ and first evidence for ${\ensuremath{\eta}}_{c}(2S)\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}\ensuremath{\eta}$.

A high-statistics measurement has been made of the process e+e−→μ+μ− at √s=29 GeV with the MAC detector at the SLAC storage ring PEP. The electroweak forward-backward charge asymmetry for a sample of approximately 16 000 events was measured to be Aμμ=−0.063±0.008±0.002. The ratio of the cross section to the lowest-order QED cross section was measured to be Rμμ=1.01±0.01±0.03. From these results the weak neutral axial-vector and vector couplings are determined to be geAgμA=0.25±0.03±0.01 and geVgμV=−0.02±0.03±0.09.Received 25 July 1985DOI:https://doi.org/10.1103/PhysRevLett.55.1831©1985 American Physical Society

A measurement of the cross section for production of collinear muon pairs based upon a sample of about 3000 events observed in the MAC detector at the storage ring PEP is presented. From the angular asymmetry ${A}_{\ensuremath{\mu}\ensuremath{\mu}}=0.076\ifmmode\pm\else\textpm\fi{}0.018$ the axial-vector weak neutral coupling is found to be given by ${{g}_{A}}^{e}{{g}_{A}}^{\ensuremath{\mu}}=0.31\ifmmode\pm\else\textpm\fi{}0.08$.

We have measured the mean lifetime of the hadrons containing b quarks that are produced in ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$ annihilation at \ensuremath{\surd}s =29 GeV. We use the full sample of data collected by the MAC detector at the SLAC storage ring, PEP, including those recently acquired with a precision vertex detector. The result is ${\ensuremath{\tau}}_{b}$=[1.29\ifmmode\pm\else\textpm\fi{}0.20(stat) \ifmmode\pm\else\textpm\fi{}0.07(syst) ps]\ifmmode\times\else\texttimes\fi{}(1.00\ifmmode\pm\else\textpm\fi{}0.15), where the last factor is the systematic uncertainty in the scale.

A search for supersymmetric electron production via the reaction ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{e}^{\ifmmode\pm\else\textpm\fi{}}\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\gamma}}{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{e}}^{\ensuremath{\mp}}$ followed by the decay ${\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{e}}^{\ensuremath{\mp}}\ensuremath{\rightarrow}{e}^{\ensuremath{\mp}}\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\gamma}}$ has been performed with the MAC detector at the electron-positron storage ring PEP. No candidates were found in a sample corresponding to an integrated luminosity of 36.4 ${\mathrm{pb}}^{\ensuremath{-}1}$. For a massless $\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\gamma}}$ this corresponds to a lower limit on the $\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{e}$ mass of 22.4 GeV/${\mathit{c}}^{2}$ at the 95% confidence level.

We present the result from a precision measurement of the mass of the $\tau$ lepton, $M_\tau$, based on $423 fb^{-1}$ of data recorded at the $\Upsilon(4S)$ resonance with the BaBar detector. Using a pseudomass endpoint method, we determine the mass to be $1776.68 \pm 0.12 (stat) \pm 0.41 (syst) MeV$. We also measure the mass difference between the $\tau^+$ and $\tau^-$, and obtain $(M_{\tau^{+}}-M_{\tau^{-}})/M^\tau_{AVG} = (-3.4 \pm 1.3 (stat) \pm 0.3 (syst)) \times 10^{-4}$, where $M^\tau_{AVG}$ is the average value of $M_{\tau^+}$ and $M_{\tau^-}$.

We have measured the production cross section for prompt muons relative to pions, produced in nucleon-nucleus interactions at incident energies from 30 to 300 GeV and for muon transverse momenta from 1 to 2.3 GeV/c. Upper limits on the production and leptonic decay of heavy particles are presented.

We present an analysis of the decays ${B}^{0}\ensuremath{\rightarrow}{K}^{*0}(892)\ensuremath{\gamma}$ and ${B}^{+}\ensuremath{\rightarrow}{K}^{*+}(892)\ensuremath{\gamma}$ using a sample of about $383\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ events collected with the BABAR detector at the PEP-II asymmetric energy $B$ factory. We measure the branching fractions $\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{K}^{*0}\ensuremath{\gamma})=(4.47\ifmmode\pm\else\textpm\fi{}0.10\ifmmode\pm\else\textpm\fi{}0.16)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$ and $\mathcal{B}({B}^{+}\ensuremath{\rightarrow}{K}^{*+}\ensuremath{\gamma})=(4.22\ifmmode\pm\else\textpm\fi{}0.14\ifmmode\pm\else\textpm\fi{}0.16)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$. We constrain the direct $CP$ asymmetry to be $\ensuremath{-}0.033&lt;\mathcal{A}(B\ensuremath{\rightarrow}{K}^{*}\ensuremath{\gamma})&lt;0.028$ and the isospin asymmetry to be $0.017&lt;{\ensuremath{\Delta}}_{0\ensuremath{-}}&lt;0.116$, where the limits are determined by the 90% confidence interval and include both the statistical and systematic uncertainties.

The ratio R(τμ)(Υ(1S))=Γ(Υ(1S)→τ+ τ-)/Γ(Υ(1S)→μ+ μ-) is measured using a sample of (121.8±1.2)×10(6)Υ(3S) events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays Υ(3S)→Υ(1S)π+ π-, Υ(1S)→l+ l-, where l=μ, τ. The result, R(τμ)(Υ(1S))=1.005±0.013(stat)±0.022(syst), shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.

We report on a search for CP violation in the decay $ D^\pm \to K^0_{\scriptscriptstyle S} \pi^\pm $ using a data set corresponding to an integrated luminosity of $ 469\,\,fb^{-1} $ collected with the \slshape B\kern-0.1em{\smaller A}\kern-0.1em B\kern-0.1em{\smaller A\kern-0.2em R} detector at the PEP-II asymmetric energy $e^+e^-$ storage rings. The CPviolating decay rate asymmetry $A_{CP}$ is determined to be $(-0.44 \pm 0.13 \mathrm{(stat)} \pm 0.10 \mathrm{(syst)})%$, consistent with zero at 2.7 $\sigma$ and with the standard model prediction of $(-0.332 \pm 0.006)%$. This is currently the most precise measurement of this parameter.

We present the first results on the Dalitz-plot structure and improved measurements of the time-dependent CP-violation parameters of the process $B^0 \rightarrow K^0_S K^0_S K^0_S$ obtained using $468\times10^{6}$ $B\bar{B}$ decays collected with the BABAR detector at the PEP-II asymmetric-energy $B$ factory at SLAC. The Dalitz-plot structure is probed by a time-integrated amplitude analysis that does not distinguish between $B^0$ and $\bar{B}^0$ decays. We measure the total inclusive branching fraction ${\cal B}($B^0$ \rightarrow K^0_S K^0_S K^0_S)=\rm (6.19 \pm 0.48 \pm 0.15 \pm 0.12)\times 10^{-6}$, where the first uncertainty is statistical, the second is systematic, and the third represents the Dalitz-plot signal model dependence. We also observe evidence for the intermediate resonant states $f_0(980)$, $f_0(1710)$, and $f_2(2010)$. Their respective product branching fractions are measured to be $\rm(2.70\,^{+1.25}_{-1.19} \pm 0.36 \pm 1.17)\times 10^{-6}$, $\rm(0.50\,^{+0.46}_{-0.24} \pm 0.04 \pm 0.10)\times 10^{-6}$, and $\rm(0.54\,^{+0.21}_{-0.20} \pm 0.03 \pm 0.52)\times 10^{-6}$. Additionally, we determine the mixing-induced CP-violation parameters to be ${\cal S} = -0.94\,^{+0.24}_{-0.21} \pm 0.06 $ and ${\cal C} = -0.17 \pm 0.18 \pm 0.04 $, where the first uncertainty is statistical and the second is systematic. These values are in agreement with the standard model expectation. For the first time, we report evidence of CP violation in $B^0$ \rightarrow K^0_S K^0_S K^0_S$ decays; CP conservation is excluded at 3.8 standard deviations including systematic uncertainties.

We have searched for the effective FCNC decays b->s l+l- using an inclusive method. We set upper limits on the branching ratios B(b->s e+e-) < 5.7 10^{-5}, B(b->s mu+mu-) < 5.8 10^{-5}, and B(b->s e+-mu-+) < 2.2 10^{-5} (at 90 %\ C.L.). Combining the di-electron and di-muon decay modes we find: B(b->s l+l-) < 4.2 10^{-5} (at 90 % C.L.).

A charge asymmetry has been observed in final-state jets from e+e− annihilation into hadrons at √s =29 GeV. The measured asymmetry is consistent with the prediction of electroweak theory. The product of axial-vector weak coupling constants, averaged over all quark flavors, is determined to be 〈gAegAq〉=-0.34±0.06±0.05.Received 21 August 1986DOI:https://doi.org/10.1103/PhysRevLett.58.1080©1987 American Physical Society

A high-statistics measurement is presented of the cross section for the process e+e−→τ+τ− at s=29 GeV from the MAC detector at PEP. A fit to the angular distribution of our sample of 10 153 events with |cosθ|<0.9 gives an asymmetry Aττ=−0.055±0.012±0.005 from which we find the product of electron and tau axial-vector weak neutral couplings gAegAτ=0.22±0.05.Received 26 December 1984DOI:https://doi.org/10.1103/PhysRevLett.54.1620©1985 American Physical Society

We report a high-precision measurement of the ratio R of the total cross section for e+e−→hadrons to that for e+e−→μ+μ−, at a center-of-mass energy of 29.0 GeV using the MAC detector. The result is R=3.96±0.09. This value of R is used to determine a value of the strong coupling constant αs of 0.23±0.06, nearly independent of fragmentation models. Two different analysis methods having quite different event-selection criteria have been used and the results are in agreement. Particular attention has been given to the study of systematic errors. New higher-order QED calculations are used for the luminosity determination and the acceptance for hadrons.Received 7 November 1984DOI:https://doi.org/10.1103/PhysRevD.31.1537©1985 American Physical Society

We present a measurement of the branching fractions of the 22 decay channels of the B0 and B+ mesons to Dbar(*)D(*)K, where the D(*) and Dbar(*) mesons are fully reconstructed. Summing the 10 neutral modes and the 12 charged modes, the branching fractions are found to be B(B0 -> Dbar(*)D(*)K) = (3.68 +- 0.10 +- 0.24)% and B(B+ -> Dbar(*)D(*)K) = (4.05 +- 0.11 +- 0.28)%, where the first uncertainties are statistical and the second systematic. The results are based on 429 fb^-1 of data containing 471.10^6 BBbar pairs collected at the Y(4S) resonance with the BaBar detector at the SLAC National Accelerator Laboratory.

IT HAS been shown by Dattner¹and others²that the spinal fluid cell count is a sensitive index of activity of the syphilitic process in the nervous system. The cell count, easily the most available and dependable of the initial test procedures, is the first to become abnormal when the nervous system is involved and is also the first to respond to specific therapy. More than 20 years ago Dattner³observed that in the malaria-treated patient the cell count returned to normal within six months after completion of the course of fever therapy. In those patients who failed to show a normal cell count six months after fever, there was progression of the disease. It has been the experience of the Penicillin-Syphilis Panel of the University Hospital⁴that after penicillin therapy for asymptomatic neurosyphilis the spinal fluid cell count usually reaches normal by the end of

Using data collected with the CLEO II detector at the Cornell Electron Storage Ring, we have studied the decays of leptons produced through e ϩ e Ϫ annihilation into final states containing K S 0 mesons, observed through their decays to ϩ Ϫ .We present branching fractions for decays to five final states: Ϫ →K 0 h Ϫ , Ϫ →K 0 h Ϫ 0 , Ϫ →K 0 K Ϫ , Ϫ →K 0 K Ϫ 0 , and Ϫ →K S 0 K S 0 h Ϫ , where K 0 h Ϫ denotes the sum of the processes involving K ¯0 Ϫ and K 0 K Ϫ particle combinations.Substructure and mass spectra in these final states are also addressed.

With the CLEO-II detector at the Cornell Electron Storage Ring, we have measured branching fractions for tau lepton decay into one-prong final states with multiple ${\mathrm{\ensuremath{\pi}}}^{0}$'s ${\mathit{B}}_{\mathit{h}\mathit{n}\mathrm{\ensuremath{\pi}}}^{0}$, normalized to the branching fraction for tau decay into one charged particle and a single ${\mathrm{\ensuremath{\pi}}}^{0}$. We find ${\mathit{B}}_{\mathit{h}2\mathrm{\ensuremath{\pi}}}^{0}$/${\mathit{B}}_{\mathit{h}\mathrm{\ensuremath{\pi}}}^{0}$=0.345\ifmmode\pm\else\textpm\fi{}0.006\ifmmode\pm\else\textpm\fi{}0.016, ${\mathit{B}}_{\mathit{h}3\mathrm{\ensuremath{\pi}}}^{0}$/${\mathit{B}}_{\mathit{h}\mathrm{\ensuremath{\pi}}}^{0}$=0.041 \ifmmode\pm\else\textpm\fi{}0.003\ifmmode\pm\else\textpm\fi{}0.005, and ${\mathit{B}}_{\mathit{h}4\mathrm{\ensuremath{\pi}}}^{0}$/${\mathit{B}}_{\mathit{h}\mathrm{\ensuremath{\pi}}}^{0}$=0.006\ifmmode\pm\else\textpm\fi{}0.002\ifmmode\pm\else\textpm\fi{}0.002.

The angular distributions of the decay Λ+c→Λe+νe have been studied using the CLEO II detector. By performing a three-dimensional maximum likelihood fit, the form factor ratio R=f2/f1 is determined to be −0.25±0.14±0.08. The decay asymmetry parameter of the Λc averaged over q2 is calculated to be αΛc=−0.82+0.09+0.06−0.06−0.03.Received 13 January 1995DOI:https://doi.org/10.1103/PhysRevLett.75.624©1995 American Physical Society

Using data from the CLEO II detector at CESR, we measure ${\cal B}(\tau^\pm\rightarrow h^\pm\pi^0\nu_\tau)$ where $h^\pm$ refers to either $\pi^\pm$ or $K^\pm$. We use three different methods to measure this branching fraction. The combined result is ${\cal B}(\tau^\pm\rightarrow h^\pm\pi^0\nu_\tau) = 0.2587 \pm 0.0012 \pm 0.0042$, in good agreement with Standard Model predictions. This result, in combination with other precision measurements, reduces the significance of the one-prong problem in tau decays. A postscript version is available through World-Wide-Web in http://w4.lns.cornell.edu/public/CLNS/1994/

Abstract The design considerations, construction techniques, prototype tests and performance characteristics of a pressurized drift chamber used in the MAC detector at PEP are described. The chamber consists of 324 aluminized mylar tubes of 6.9 mm diameter with wall thickness of 100 μm. With appropriate shielding it operates successfully at 4.6 cm from the beam line. It was simple to construct and was configured to permit any malfunctioning tubes to be remotely disconnected without affecting operation. The chamber operated without problems for two years in the PEP environment with a gas mixture of 49.5% argon, 49.5% CO 2 , 1% CH 4 , at 4 atm absolute pressure. The mean spatial resolution averaged over all tubes was 45 μm. The time to distance relation for this gas mixture, along with the geometric positioning of individual wires relative to the central tracking chamber, was obtained with data from Bhabha scattering events. We also describe resolution studies performed with a prototype chamber in a SLAC test beam. A wide range of gases, gas pressures, and electronic parameters were explored. These studies proved that resolutions in the 10–50 μm range were possible. Our experience demonstrates that chambers of this type provide high precision tracking and are particularly suited for operation in regions with difficult physical access and/or high ambient radiation levels.

A search for single photons produced in association with neutrinos or other weakly interacting neutral particles has been performed in e+e− annihilations at √s=29 GeV with the MAC detector at the SLAC e+e− storage ring PEP. One event is observed, with 1.1 events expected from the reaction e+e−→ν¯νγ. The number of neutrino families is restricted to Nν<17 at the 90% confidence level. Limits on possible masses of supersymmetric electrons (˜e) and photons (˜γ) are presented. The ˜e mass limit is m˜e>48 GeV/c2 at the 90% confidence level if m˜eL=m˜eR and m˜γ=0. If m˜eL>>m˜eR, the corresponding limit is m˜eR>40 GeV/c2.Received 20 March 1986DOI:https://doi.org/10.1103/PhysRevD.33.3472©1986 American Physical Society

Charged-lepton flavor-violating processes are unobservable in the standard model, but they are predicted to be enhanced in several extensions to the standard model, including supersymmetry and models with leptoquarks or compositeness. We present a search for such processes in a sample of 99x10(6)Upsilon(2S) decays and 117x10(6)Upsilon(3S) decays collected with the BABAR detector. We place upper limits on the branching fractions B(Upsilon(nS)-->e(+/-)tau(-/+)) and B(Upsilon(nS)-->mu(+/-)tau(-/+)) (n=2,3) at the 10(-6) level and use these results to place lower limits of order 1 TeV on the mass scale of charged-lepton flavor-violating effective operators.

We report the measurement of the baryonic B decay B- -> SigmaC++ p- pi- pi-. Using a data sample of 467*10^6 B B-bar pairs collected with the BaBar detector at the PEP-II storage ring at SLAC, the measured branching fraction is (2.98 +/- 0.16 (stat) +/- 0.15 (syst) +/- 0.77 (LambdaC+))*10^{-4}, where the last error is due to the uncertainty in the branching fraction of the decay LambdaC+ -> p+ K- pi+. The data suggest the existence of resonant subchannels B- -> LambdaC(2595)+ p- pi- and, possibly, B- -> SigmaC++ anti-Delta-- pi-. We see unexplained structures in m(SigmaC++ pi- pi-) at 3.25 GeV/c^2, 3.8 GeV/c^2, and 4.2 GeV/c^2.

We use (111±1) million Υ(3S) and (89±1) million Υ(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions between bottomonium states using photons that have been converted to e+e− pairs by the detector material. We observe Υ(3S)→γχb0,2(1P) decay, make precise measurements of the branching fractions for χb1,2(1P,2P)→γΥ(1S) and χb1,2(2P)→γΥ(2S) decays, and search for radiative decay to the ηb(1S) and ηb(2S) states.1 MoreReceived 27 April 2011Corrected 18 October 2011DOI:https://doi.org/10.1103/PhysRevD.84.072002© 2011 American Physical Society

We report an analysis of the charmless hadronic decays of charged B meson to the final state K+pi0pi0, using a data sample of 470+/-2.8 million BBbar events collected at the Y(4S) resonance. We observe an excess of signal events, with a significance above 10 standard deviations including systematic uncertainties, and measure the branching fraction and CP asymmetry to be B(B+->K+pi0pi0)=(16.2+/-1.2+/-1.5)x10^-6 and A_CP(B+->K+pi0pi0)=-0.06+/-0.06+/-0.04, where the uncertainties are statistical and systematic respectively. Additionally we study the contributions of the B+->K*(892)+pi0, B+->f0(980)K+ and B+->chic0K+ quasi-two body decays. We report the world's best measurements of the branching fractions and CP asymmetry of the B+->K+pi0pi0 and B+->K*(892)+pi0 channels.

The $e^+e^-\to K^+K^-$ cross section and charged-kaon electromagnetic form factor are measured in the $e^+e^-$ center-of-mass energy range ($E$) from 2.6 to 8.0 GeV using the initial-state radiation technique with an undetected photon. The study is performed using 469 fb$^{-1}$ of data collected with the BABAR detector at the PEP-II $e^+e^-$ collider at center-of-mass energies near 10.6 GeV. The form factor is found to decrease with energy faster than $1/E^2$, and approaches the asymptotic QCD prediction. Production of the $K^+K^-$ final state through the $J/\psi$ and $\psi(2S)$ intermediate states is observed. The results for the kaon form factor are used together with data from other experiments to perform a model-independent determination of the relative phases between single-photon and strong amplitudes in $J/\psi$ and $\psi(2S)\to K^+K^-$ decays. The values of the branching fractions measured in the reaction $e^+e^- \to K^+K^-$ are shifted relative to their true values due to interference between resonant and nonresonant amplitudes. The values of these shifts are determined to be about $\pm5\%$ for the $J/\psi$ meson and $\pm15\%$ for the $\psi(2S)$ meson.

We report on measurements of the decays of B¯ mesons into the semileptonic final states B¯→D^(*)π^(+)π^(-)ℓ^(-)ν¯, where D^(*) represents a D or D^(*) meson and ℓ^(-) is an electron or a muon. These measurements are based on 471×10^(6) BB ¯ pairs recorded with the BABAR detector at the SLAC asymmetric B factory PEP-II. We determine the branching fraction ratios R_{π^{+}π^{-}}^{(*)}=B(B[over ¯]→D^{(*)}π^{+}π^{-}ℓ^{-}ν[over ¯])/B(B[over ¯]→D^{(*)}ℓ^{-}ν[over ¯]) using events in which the second B meson is fully reconstructed. We find R_{π^{+}π^{-}}=0.067±0.010±0.008 and R_{π^{+}π^{-}}^{*}=0.019±0.005±0.004, where the first uncertainty is statistical and the second is systematic. Based on these results and assuming isospin invariance, we estimate that B[over ¯]→D^{(*)}ππℓ^{-}ν[over ¯] decays, where π denotes either a π^{±} and π^{0} meson, account for up to half the difference between the measured inclusive semileptonic branching fraction to charm hadrons and the corresponding sum of previously measured exclusive branching fractions.

Congestive failure has been considered a relative contraindication to antisyphilitic therapy in cardiovascular syphilis since the arsphenamine era, when severe reactions were reported following administration of this vasculotoxic drug. After having observed no severe reactions to penicillin in a series of patients with cardiovascular syphilis, it was decided to administer the antibiotic as initial therapy for individuals in congestive failure. This report summarizes observations on twelve such patients. There were no severe reactions during the course of treatment in the entire group. Digitalis and other measures to restore compensation were used concomitantly with penicillin. All the patients were improved upon completion of therapy. Case histories of 2 patients who died two months after treatment, are given. The significance of observations on the entire group is discussed.

Branching ratios for the dominant Cabibbo-suppressed decays of the $\ensuremath{\tau}$ lepton have been measured by CLEO II in ${e}^{+}{e}^{\ensuremath{-}}$ annihilation at the Cornell Electron Storage Ring ($\sqrt{s}\ensuremath{\sim}10.6$ GeV) using kaons with momenta below 0.7 GeV/c. The inclusive branching ratio into one charged kaon is (1.60 \ifmmode\pm\else\textpm\fi{} 0.12 \ifmmode\pm\else\textpm\fi{} 0.19)%. For the exclusive decays, $B({\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\nu}}_{\ensuremath{\tau}})=(0.66\ifmmode\pm\else\textpm\fi{}0.07\ifmmode\pm\else\textpm\fi{}0.09)%$, $B({\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}{\ensuremath{\nu}}_{\ensuremath{\tau}})=(0.51\ifmmode\pm\else\textpm\fi{}0.10\ifmmode\pm\else\textpm\fi{}0.07)%$, and, based on three events, $B({\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}2{\ensuremath{\pi}}^{0}{\ensuremath{\nu}}_{\ensuremath{\tau}})&lt;0.3%$ at the 90% confidence level. These represent significant improvements over previous results. $B({\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}{\ensuremath{\nu}}_{\ensuremath{\tau}})$ is measured for the first time with exclusive ${\ensuremath{\pi}}^{0}$ reconstruction.

Neutrinoless 3-prong tau lepton decays into a charged lepton and either two charged particles or one neutral meson have been searched for using $4.79{\mathrm{fb}}^{\mathrm{\ensuremath{-}}1}$ of data collected with the CLEO II detector at Cornell Electron Storage Ring. This analysis represents an update of a previous study and the addition of six decay channels. In all channels the numbers of events found are compatible with background estimates and branching fraction upper limits are set for 28 different decay modes. These limits are either more stringent than those set previously or represent the first attempt to find these decays.