We report a Dalitz plot analysis of charmless hadronic decays of charged $B$ mesons to the final state $K_{\rm S}^{0}\pi^{+}\pi^{0}$ using the full BaBar dataset of $470.9\pm2.8$ million $B\bar{B}$ events collected at the $\Upsilon(4S)$ resonance. We measure the overall branching fraction and $CP$ asymmetry to be ${\cal B}\left(B^{+}\to K^{0}\pi^{+}\pi^{0}\right) = \left(45.9 \pm 2.6 \pm 3.0^{+8.6}_{-0.0}\right)\times10^{-6}$ and $A_{CP}\left(B^{+}\to K^{0}\pi^{+}\pi^{0}\right) = 0.07 \pm 0.05 \pm 0.03^{+0.02}_{-0.03}$, where the uncertainties are statistical, systematic, and due to the signal model, respectively. This is the first measurement of the branching fraction for $B^{+} \to K^{0}\pi^{+}\pi^{0}$. We find first evidence of a $CP$ asymmetry in $B^{+}\to K^{*}(892)^{+}\pi^{0}$ decays: $A_{CP}\left(B^{+}\to K^{*}(892)^{+}\pi^{0}\right)=-0.52 \pm 0.14 \pm 0.04^{+0.04}_{-0.02}$. The significance of this asymmetry, including systematic and model uncertainties, is $3.4$ standard deviations. We also measure the branching fractions and $CP$ asymmetries for three other intermediate decay modes.

We report on measurements of the decays of $\overline{B}$ mesons into the semileptonic final states $\overline{B} \to D^{(*)} \pi^+\pi^- \ell^-\overline{\nu}$, where $D^{(*)}$ represents a $D$ or $D^*$ meson and $\ell^-$ is an electron or a muon. These measurements are based on $471\times 10^6$ $B\overline{B}$ pairs recorded with the $BABAR$ detector at the SLAC asymmetric $B$ Factory PEP-II. We determine the branching fraction ratios $R^{(*)}_{\pi^+\pi^-} = \mathcal{B}(\overline{B} \to D^{(*)} \pi^+\pi^- \ell^- \overline{\nu})/\mathcal{B}(\overline{B} \to D^{(*)} \ell^-\overline{\nu})$ using events in which the second $B$ meson is fully reconstructed. We find $R_{\pi^+\pi^-} = 0.067 \pm 0.010 \pm 0.008$ and $R^*_{\pi^+\pi^-} = 0.019 \pm 0.005 \pm 0.004$, where the first uncertainty is statistical and the second is systematic. Based on these results, we estimate that $\overline{B} \to D^{(*)}\pi\pi\ell^-\overline{\nu}$ decays, where $\pi$ denotes both a $\pi^\pm$ and $\pi^0$ 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.

We study the lepton forward-backward asymmetry AFB and the longitudinal K* polarization FL, as well as an observable P2 derived from them, in the rare decays B->K*l+l-, where l+l- is either e+e- or mu+mu-, using the full sample of 471 million BBbar events collected at the Upsilon(4S) resonance with the Babar detector at the PEP-II e+e- collider. We separately fit and report results for the B+->K*+l+l- and B0->K*0l+l- final states, as well as their combination B->K*l+l-, in five disjoint dilepton mass-squared bins. An angular analysis of B+->K*+l+l- decays is presented here for the first time.

We measure the time-dependent CP asymmetry in the radiative-penguin decay B 0 → K 0 S π − π þ γ , using a sample of 471 × 10 6 ϒ ð 4 S Þ → B ¯ B events recorded with the BABAR detector at the PEP-II e þ e − storage ring at SLAC. Using events with m K ππ < 1 . 8 GeV =c 2 , we measure the branching fractions of B þ → K þ π − π þ γ and B 0 → K 0 π − π þ γ , the branching fractions of the kaonic resonances decaying to K þ π − π þ , as well as the overall branching fractions of the B þ → ρ 0 K þ γ , B þ → K (cid:2) 0 π þ γ and S -wave B þ → ð K π Þ (cid:2) 00 π þ γ components. For events from the ρ mass band, we measure the CP -violating parameters S K 0 S π þ π − γ ¼ 0 . 14 (cid:3) 0 . 25 (cid:3) 0 . 03 and C K 0 S π þ π − γ ¼ − 0 . 39 (cid:3) 0 . 20 þ 0 . 03 − 0 . 02 , where the first uncertainties are statistical and the second are systematic. We extract from this measurement the time-dependent CP asymmetry related to the CP eigenstate ρ 0 K 0 S and obtain S K 0 S ργ ¼ − 0 . 18 (cid:3) 0 . 32 þ 0 . 06 − 0 . 05 , which provides information on the photon polarization in the underlying b → s γ transition.

We describe in detail a previously published measurement of CP violation induced by B0-anti B0 oscillations, based on an integrated luminosity of 425.7 fb-1 collected by the BABAR experiment at the PEPII collider. We apply a novel technique to a sample of about 6 million B0bar -> D*+ l- nubar decays selected with partial reconstruction of the D*+ meson. The charged lepton identifies the flavor of one B meson at its decay time, the flavor of the other B is determined by kaon tagging. We determine a CP violating asymmetry ACP = (0.0006 +- 0.0017 + 0.0038 - 0.0032). This measurement is consistent and competitive with those obtained at the B factories with dilepton events.

Citation Del Amo Sanchez, P., J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, et al. “Time-Dependent Analysis of B[superscript 0] K[0 over S][superscript ][superscript +] Decays and Studies of the K[superscript +][superscript ][superscript +] System in B[superscript +] K[superscript +][superscript ][superscript +] decays.” Phys. Rev. D 93, no. 5 (March 29, 2016). © 2016 American Physical Society

Charge asymmetry in the processes e(+)e(-) -> mu(+)mu(-)gamma and e(+)e(-) -> pi(+)pi(-)gamma is measured using 232 fb(-1) of data collected with the BABAR detector at e(+)e(-) center-of-mass energies near 10.58 GeV. An observable is introduced and shown to be very robust against detector asymmetries while keeping a large sensitivity to the physical charge asymmetry that results from the interference between initial-and final-state radiation (FSR). The asymmetry is determined as a function of the invariant mass of the final-state tracks from production threshold to a few GeV/c(2). It is compared to the expectation from QED for e(+)e(-) -> mu(+)mu(-)gamma, and from theoretical models for e(+)e(-) -> pi(+)pi(-)gamma. A clear interference pattern is observed in e(+)e(-) -> pi(+)pi(-)gamma, particularly in the vicinity of the f(2)(1270) resonance. The inferred rate of lowest-order FSR production is consistent with the QED expectation for e(+)e(-) -> mu(+)mu(-)gamma, and is negligibly small for e(+)e(-) -> pi(+)pi(-)gamma.

We report a measurement of the time-dependent CP asymmetry of B[over ¯]^{0}→D_{CP}^{(*)}h^{0} decays, where the light neutral hadron h^{0} is a π^{0}, η, or ω meson, and the neutral D meson is reconstructed in the CP eigenstates K^{+}K^{-}, K_{S}^{0}π^{0}, or K_{S}^{0}ω. The measurement is performed combining the final data samples collected at the ϒ(4S) resonance by the BABAR and Belle experiments at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain (471±3)×10^{6} BB[over ¯] pairs recorded by the BABAR detector and (772±11)×10^{6} BB[over ¯] pairs recorded by the Belle detector. We measure the CP asymmetry parameters -η_{f}S=+0.66±0.10(stat)±0.06(syst) and C=-0.02±0.07(stat)±0.03(syst). These results correspond to the first observation of CP violation in B[over ¯]^{0}→D_{CP}^{(*)}h^{0} decays. The hypothesis of no mixing-induced CP violation is excluded in these decays at the level of 5.4 standard deviations.

A search is presented for the decay Υ(1S)→ γA^0, A^0 → cc[bar], where A^0 is a candidate for the CP-odd Higgs boson of the next-to-minimal supersymmetric standard model. The search is based on data collected with the BABAR detector at the Υ(2S) resonance. A sample of Υ(1S) mesons is selected via the decay Υ(2S)→π + π − Υ(1S). The A^0 → cc[bar] decay is identified through the reconstruction of hadronic D^0, D^+, and D^∗ (2010)^+ meson decays. No significant signal is observed. The measured 90% confidence-level upper limits on the product branching fraction B(Υ(1S) → γA^0 ) × B(A^0 → cc[bar] ) range from 7.4×10^(−5) to 2.4×10^(−3) for A^0 masses from 4.00 to 8.95  GeV/c^2 and 9.10 to 9.25  GeV/c^2, where the region between 8.95 and 9.10  GeV/c^2 is excluded because of background from Υ(2S) → γχ_(bJ) (1P), χ_(bJ) (1P) → γΥ(1S) decays.

J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, B. Stugu, D. N. Brown, L. T. Kerth, Yu. G. Kolomensky, M. J. Lee, G. Lynch, H. Koch, T. Schroeder, C. Hearty, T. S. Mattison, J. A. McKenna, R. Y. So, A. Khan, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, V. B. Golubev, E. A. Kravchenko, A. P. Onuchin, S. I. Serednyakov, Yu. I. Skovpen, E. P. Solodov, K. Yu. Todyshev, A. J. Lankford, M. Mandelkern, B. Dey, J. W. Gary, O. Long, C. Campagnari, M. Franco Sevilla, T. M. Hong, D. Kovalskyi, J. D. Richman, C. A. West, A. M. Eisner, W. S. Lockman, W. Panduro Vazquez, B. A. Schumm, A. Seiden, D. S. Chao, C. H. Cheng, B. Echenard, K. T. Flood, D. G. Hitlin, T. S. Miyashita, P. Ongmongkolkul, F. C. Porter, R. Andreassen, Z. Huard, B. T. Meadows, B. G. Pushpawela, M. D. Sokoloff, L. Sun, P. C. Bloom, W. T. Ford, A. Gaz, J. G. Smith, S. R. Wagner, R. Ayad, W.H. Toki, B. Spaan, D. Bernard, M. Verderi, S. Playfer, D. Bettoni, C. Bozzi, R. Calabrese, G. Cibinetto, E. Fioravanti, I. Garzia, E. Luppi, L. Piemontese, V. Santoro, A. Calcaterra, R. de Sangro, G. Finocchiaro, S. Martellotti, P. Patteri, I. M. Peruzzi, M. Piccolo, M. Rama, A. Zallo, R. Contri, M. Lo Vetere, M. R. Monge, S. Passaggio, C. Patrignani, E. Robutti, B. Bhuyan, V. Prasad, A. Adametz, U. Uwer, H. M. Lacker, P. D. Dauncey, U. Mallik, C. Chen, J. Cochran, S. Prell, H. Ahmed, A. V. Gritsan, N. Arnaud, M. Davier, D. Derkach, G. Grosdidier, F. Le Diberder, A. M. Lutz, B. Malaescu, P. Roudeau, A. Stocchi, G. Wormser, D. J. Lange, D. M. Wright, J. P. Coleman, J. R. Fry, E. Gabathuler, D. E. Hutchcroft, D. J. Payne, C. Touramanis, A. J. Bevan, F. Di Lodovico, R. Sacco, G. Cowan, J. Bougher, D. N. Brown, C. L. Davis, A. G. Denig, M. Fritsch, W. Gradl, K. Griessinger, A. Hafner, K. R. Schubert, R. J. Barlow,39,∥ G. D. Lafferty, R. Cenci, B. Hamilton, A. Jawahery, D. A. Roberts, R. Cowan, G. Sciolla, R. Cheaib, P. M. Patel, S. H. Robertson, N. Neri, F. Palombo, L. Cremaldi, R. Godang, P. Sonnek, D. J. Summers, M. Simard, P. Taras, G. De Nardo, G. Onorato, C. Sciacca, M. Martinelli, G. Raven, C. P. Jessop, J. M. LoSecco, K. Honscheid, R. Kass, E. Feltresi, M. Margoni, M. Morandin, M. Posocco, M. Rotondo, G. Simi, F. Simonetto, R. Stroili, S. Akar, E. Ben-Haim, M. Bomben, G. R. Bonneaud, H. Briand, G. Calderini, J. Chauveau, Ph. Leruste, G. Marchiori, J. Ocariz, M. Biasini, E. Manoni, S. Pacetti, A. Rossi, C. Angelini, G. Batignani, S. Bettarini, M. Carpinelli, G. Casarosa, A. Cervelli, M. Chrzaszcz, F. Forti, M. A. Giorgi, A. Lusiani, B. Oberhof, E. Paoloni, A. Perez, G. Rizzo, J. J. Walsh, D. Lopes Pegna, J. Olsen, A. J. S. Smith, R. Faccini, F. Ferrarotto, F. Ferroni, M. Gaspero, L. Li Gioi, A. Pilloni, G. Piredda, C. Bünger, S. Dittrich, O. Grünberg, M. Hess, T. Leddig, C. Voß, R. Waldi, T. Adye, E. O. Olaiya, F. F. Wilson, S. Emery, G. Vasseur, F. Anulli, D. Aston, D. J. Bard, C. Cartaro, M. R. Convery, J. Dorfan, G. P. Dubois-Felsmann, W. Dunwoodie, M. Ebert, R. C. Field, B. G. Fulsom, M. T. Graham, C. Hast, W. R. Innes, P. Kim, D.W. G. S. Leith, P. Lewis, D. Lindemann, S. Luitz, V. Luth, H. L. Lynch, D. B. MacFarlane, D. R. Muller, H. Neal, M. Perl, T. Pulliam, B. N. Ratcliff, A. Roodman, A. A. Salnikov, R. H. Schindler, A. Snyder, D. Su, M. K. Sullivan, J. Va’vra, W. J. Wisniewski, H.W. Wulsin, M. V. Purohit, R. M. White, J. R. Wilson, A. Randle-Conde, S. J. Sekula, M. Bellis, P. R. Burchat, E. M. T. Puccio, M. S. Alam, J. A. Ernst, R. Gorodeisky, N. Guttman, D. R. Peimer, A. Soffer, S. M. Spanier, J. L. Ritchie, A. M. Ruland, R. F. Schwitters, B. C. Wray, J. M. Izen, X. C. Lou, F. Bianchi, F. De Mori, A. Filippi, D. Gamba, L. Lanceri, L. Vitale, F. Martinez-Vidal, A. Oyanguren, P. Villanueva-Perez, J. Albert, Sw. Banerjee, A. Beaulieu, F. U. Bernlochner, H. H. F. Choi, G. J. King, R. Kowalewski, M. J. Lewczuk, T. Lueck, I. M. Nugent, J. M. Roney, R. J. Sobie, N. Tasneem, T. J. Gershon, P. F. Harrison, T. E. Latham, H. R. Band, S. Dasu, Y. Pan, R. Prepost, and S. L. Wu

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.

We present a measurement of the asymmetry A_{CP} between same-sign inclusive dilepton samples ℓ^{+}ℓ^{+} and ℓ^{-}ℓ^{-} (ℓ=e, μ) from semileptonic B decays in ϒ(4S)→BB[over ¯] events, using the complete data set recorded by the BABAR experiment near the ϒ(4S) resonance, corresponding to 471×10^{6} BB[over ¯] pairs. The asymmetry A_{CP} allows comparison between the mixing probabilities P(B[over ¯]^{0}→B^{0}) and P(B^{0}→B[over ¯]^{0}), and therefore probes CP and T violation. The result, A_{CP}=[-3.9±3.5(stat)±1.9(syst)]×10^{-3}, is consistent with the standard model expectation.

plot analyses of B[superscript 0] D[superscript ]D[superscript 0]K[superscript +] and B[superscript +] [bar over D][superscript 0]D[superscript 0]K[superscript Citation Lees, J. P., et al. "Dalitz plot analyses of B[superscript 0] D[superscript ]D[superscript 0]K[superscript +] and B[superscript +] [bar over D][superscript 0]D[superscript 0]K[superscript +] decays. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.

We perform a measurement of the τ → lγνν¯ (l = e,μ) branching fractions for a minimum photon energy of 10 MeV in the τ rest frame, using 431 fb–1 of e+e– collisions collected at the center-of-mass energy of the Υ(4S) resonance with the BABAR detector at the PEP-II storage rings. We find B(τ → μγνν¯) = (3.69±0.03±0.10)×10–3 and B(τ → eγνν¯)=(1.847±0.015±0.052)×10–2, where the first quoted error is statistical and the second is systematic. In addition, these results are substantially more precise than previous measurements.