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Showing papers by "D. Dujmic published in 2008"


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +559 moreInstitutions (78)
TL;DR: In this paper, the authors report measurements of processes: e+e-→γKS0K±π∓ (e+e −δ), e−e −→γK+K-π0, e−δ→γϕη, and e−E −→ϕππ0.
Abstract: This paper reports measurements of processes: e+e-→γKS0K±π∓, e+e-→γK+K-π0, e+e-→γϕη, and e+e-→γϕπ0. The initial-state radiated photon allows to cover the hadronic final state in the energy range from thresholds up to ≈4.6 GeV. The overall size of the data sample analyzed is 232 fb-1, collected by the BABAR detector running at the PEP-II e+e- storage ring. From the Dalitz plot analysis of the KS0K±π∓ final state, moduli, and relative phase of the isoscalar and the isovector components of the e+e-→KK*(892) cross section are determined. Parameters of ϕ and ρ recurrences are also measured, using a global fitting procedure which exploits the interconnection among amplitudes, moduli, and phases of the e+e-→KS0K±π∓, K+K-π0, ϕη final states. The cross section for the OZI-forbidden process e+e-→ϕπ0, and the J/ψ branching fractions to KK*(892) and K+K-η are also measured.

150 citations


Journal ArticleDOI
B. Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +567 moreInstitutions (77)
TL;DR: In this paper, a study of the decays B;{0,+}-->J/psiomegaK using 383x10;{6} BB[over ] events obtained with the BABAR detector at PEP-II is presented.
Abstract: We present a study of the decays B;{0,+}-->J/psiomegaK;{0,+} using 383x10;{6} BB[over ] events obtained with the BABAR detector at PEP-II. We observe Y(3940)-->J/psiomega, with mass 3914.6_{-3.4};{+3.8}(stat)+/-2.0(syst) MeV/c;{2}, and width 34_{-8};{+12}(stat)+/-5(syst) MeV. The ratio of B0 and B+ decay to YK is 0.27_{-0.23};{+0.28}(stat)-0.01+0.04(syst), and the relevant B0 and B+ branching fractions are reported.

146 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +560 moreInstitutions (76)
TL;DR: In this article, a study of resonances in exclusive decays of $B$ mesons to the BaBar detector is presented, where the decay of the mesons is investigated.
Abstract: We present a study of resonances in exclusive decays of $B$ mesons to $\bar{D}^{(*)} D^{(*)} K$. We report the observation of the decays $B \to \Dbar^{(*)} D^+_{s1}(2536)$ where the $D^+_{s1}(2536)$ is reconstructed in the $D^{*0}K^+$ and $D^{*+} K^0_S$ decay channels. We report also the observation of the decays $B \to \psi(3770) K$ where the $\psi(3770)$ decays to $\Dbar^0 D^0$ and $D^- D^+$. In addition, we present the observation of an enhancement for the $\Dbar^{*0} D^0$ invariant mass in the decays $B \to \Dbar^{*0} D^0 K$, at a mass of $(3875.1 {}^{+0.7}_{-0.5} \pm 0.5)$ MeV/$c^2$ with a width of $(3.0 {}^{+1.9}_{-1.4} \pm 0.9)$ MeV (the first errors are statistical and the second are systematic). Branching fractions and spin studies are shown for the three resonances. The results are based on 347 fb$^{-1}$ of data collected with the BaBar detector at the PEP-II $B$ factory.

128 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +556 moreInstitutions (78)
TL;DR: In this paper, the branching fraction and photon-energy spectrum for the decay B -> X-s gamma were measured using data from the BABAR experiment. But the measurement was limited to a single B meson.
Abstract: We present a measurement of the branching fraction and photon-energy spectrum for the decay B -> X-s gamma using data from the BABAR experiment. The data sample corresponds to an integrated luminosity of 210 fb(-1), from which approximately 680 000 B (B) over bar events are tagged by a fully reconstructed hadronic decay of one of the B mesons. In the decay of the second B meson, an isolated high-energy photon is identified. We measure B(B -> X-s gamma) = (3.66 +/- 0.85(stat) +/- 0.60(syst)) x 10(-4) for photon energies E-gamma above 1.9 GeV in the B rest frame. From the measured spectrum we calculate the first and second moments for different minimum photon energies, which are used to extract the heavy-quark parameters m(b) and mu(2)(pi). In addition, measurements of the direct CP asymmetry and isospin asymmetry are presented.

121 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +535 moreInstitutions (79)
TL;DR: In this paper, the authors reported the results of a search for the bottomonium ground state {eta}{sub b}(1S) in the photon energy spectrum with a sample of (109 {+-} 1) million of {Upsilon}(3S) recorded at the Upsilon 3S energy with the BABAR detector at SLAC.
Abstract: The authors report the results of a search for the bottomonium ground state {eta}{sub b}(1S) in the photon energy spectrum with a sample of (109 {+-} 1) million of {Upsilon}(3S) recorded at the {Upsilon}(3S) recorded at the {Upsilon}(3S) energy with the BABAR detector at the PEP-II B factory at SLAC. They observe a peak in the photon energy spectrum at E{sub {gamma}} = 921.2{sub -2.8}{sup +2.1}(stat) {+-} 2.4(syst) MeV with a significance of 10 standard deviations. They interpret the observed peak as being due to monochromatic photons from the radiative transition {Upsilon}(3S) {yields} {gamma} {eta}{sub b}(1S). This photon energy corresponds to an {eta}{sub b}(1S) mass of 9388.9{sub -2.3}{sup +3.1}(stat) {+-} 2.7(syst) MeV/c{sup 2}. The hyperfine {Upsilon}(1S)-{eta}{sub b}(1S) mass splitting is 71.4{sub -3.1}{sup +2.3}(stat) {+-} 2.7(syst) MeV/c{sup 2}. The branching fraction for this radiative {Upsilon}(3S) decay is estimated to be (4.8 {+-} 0.5(stat) {+-} 1.2(syst)) x 10{sup -4}.

119 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +539 moreInstitutions (78)
TL;DR: In this paper, the authors presented measurements of the decays B+ -> X(3872) K+ and B0-K0 with X( 3872) -> Jpsi pi+ pi-.
Abstract: We present measurements of the decays B+ -> X(3872) K+ and B0 -> X(3872) K0 with X(3872) -> Jpsi pi+ pi-. The data sample used, collected with the BABAR detector at the PEP-II e+e- asymmetric-energy storage ring, corresponds to 455 x 10^6 BBbar pairs. Branching fraction measurements of BF(B+ -> X(3872) K+) x BF(X(3872) -> Jpsi pi+ pi-) = (8.4 +/- 1.5 +/- 0.7) x 10^{-6} and BF(B0 -> X(3872) K0) x BF(X(3872) -> Jpsi pi+ pi- = (3.5 +/- 1.9 +/- 0.4) x 10^{-6} are obtained. We set an upper limit on the natural width of the X(3872) of Gamma < 3.3 MeV/c^2 at the 90% confidence level.

99 citations


Journal ArticleDOI
B. Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +539 moreInstitutions (78)
TL;DR: In this article, a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the final state K+/-pi+/- pi-/+. using a sample of 383.2 +/- 4.2 million BBbar pairs collected by the BaBar detector, they measure CP-averaged branching fractions and direct CP asymmetries for intermediate resonant and nonresonant contributions.
Abstract: We report a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the final state K+/- pi+/- pi-/+. Using a sample of 383.2 +/- 4.2 million BBbar pairs collected by the BaBar detector, we measure CP-averaged branching fractions and direct CP asymmetries for intermediate resonant and nonresonant contributions. We find evidence for direct CP violation in the decay B+ -> rho0(770) K+, with a CP violation parameter A_CP = (+44 +/- 10 +/- 4 +5,-13)%.

95 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +559 moreInstitutions (77)
TL;DR: Measurements are presented of the semileptonic decays B--->D0tau-nutau, B- and B0, B0-->D+Tau-nutsau, and B 0-->D*+tAU-nutAU, which are potentially sensitive to non-standard model amplitudes, and normalization-mode-related.
Abstract: We present measurements of the semileptonic decays B--->D0tau-nutau, B--->D*0tau-nutau, B0-->D+tau-nutau, and B0-->D*+tau-nutau, which are potentially sensitive to non-standard model amplitudes. The data sample comprises 232x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector. From a combined fit to B- and B0 channels, we obtain the branching fractions B(B-->Dtau-nutau)=(0.86+/-0.24+/-0.11+/-0.06)% and B(B-->D*tau-nutau)=(1.62+/-0.31+/-0.10+/-0.05)% (normalized for the B0), where the uncertainties are statistical, systematic, and normalization-mode-related.

90 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +539 moreInstitutions (78)
TL;DR: In this paper, an improved measurement of the Cabibbo-KobayashiMaskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson was reported.
Abstract: We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{bar B} pairs collected by the BABAR detector, we measure {gamma} = (76 {+-} 22 {+-} 5{+-} 5){sup o} (mod 180{sup o}), where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the uncertainty on the description of the Dalitz plot distributions. The corresponding two standard deviation region is 29{sup o} < {gamma} < 122{sup o}. This result has a significance of direct CP violation ({gamma} {ne} 0) of 3.0 standard deviations.

74 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +562 moreInstitutions (77)
TL;DR: In this article, the authors measure time-integrated CP-violating asymmetries of neutral charmed mesons in the modes D0 --> K(-) K(+) and D0--> pi(-) pi(+) with the highest precision to date.
Abstract: We measure time-integrated CP-violating asymmetries of neutral charmed mesons in the modes D0 --> K(-) K(+) and D0 --> pi(-) pi(+) with the highest precision to date by using D0 --> K(-) pi(+) decays to correct detector asymmetries. An analysis of 385.8 fb(-1) of data collected with the BABAR detector yields values of a(CP)(KK)=(0.00+/-0.34(stat)+/-0.13(syst))% and a(CP)(pipi)=(-0.24+/-0.52(stat)+/-0.22(syst))%, which agree with standard model predictions.

69 citations


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +569 moreInstitutions (77)
TL;DR: In this article, a study of excited charm-strange baryons produced in e{sup +}e{sup -} annihilations at or near a center-of-mass energy of 10.58 GeV is presented.
Abstract: We present a study of excited charm-strange baryon states produced in e{sup +}e{sup -} annihilations at or near a center-of-mass energy of 10.58 GeV, in a data sample with an integrated luminosity of 384 fb{sup -1} recorded with the BABAR detector at the PEP-II e+e storage rings at the Stanford Linear Accelerator Center. We study strong decays of charm-strange baryons to {Lambda}{sub c}{sup +}K{sub S}{sup 0}, {Lambda}{sub c}{sup +}K{sup -}, {Lambda}{sub c}{sup +}K{sup -}{pi}{sup +}, {Lambda}{sub c}{sup +}K{sub S}{sup 0}{pi}{sup -}, {Lambda}{sub c}{sup +}K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}, {Lambda}{sub c}{sup +}K{sup -}{pi}{sup -}{pi}{sup +}. This study confirms the existence of the states {Xi}{sub c}(2980){sup +}, {Xi}{sub c}(3077){sup +}, and {Xi}{sub c}(3077){sup -}, with a more accurate determination of the {Xi}{sub c}(2980){sup +} mass and width. We also present evidence for two new states, {Xi}{sub c}(3055){sup +} and {Xi}{sub c}(3123){sup +}, decaying through the intermediate resonant modes {Sigma}{sub c}(2455){sup ++}K{sup -} and {Sigma}{sub c}(2520){sup ++}K{sup -}, respectively. For each of these baryons, we measure the yield in each final state, determine the statistical significance, and calculate the product of the production cross-section and branching fractions. We also measure the masses and widths of these excited charm-strange baryons.


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +563 moreInstitutions (77)
TL;DR: In this paper, the decay of B{sup + yields}D{sup (*)0}X{sup -} was investigated using 383x10{sup 6} BB pairs collected at the SLAC PEP-II B Factory.
Abstract: We present a search for the decay B{sup +}{yields}{tau}{sup +}{nu} using 383x10{sup 6} BB pairs collected at the {upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B Factory. We select a sample of events with one completely reconstructed tag B in a hadronic decay mode (B{sup -}{yields}D{sup (*)0}X{sup -}), and examine the rest of the event to search for a B{sup +}{yields}{tau}{sup +}{nu} decay. We identify the {tau} lepton in the following modes: {tau}{sup +}{yields}e{sup +}{nu}{nu}, {tau}{sup +}{yields}{mu}{sup +}{nu}{nu}, {tau}{sup +}{yields}{pi}{sup +}{nu}, and {tau}{sup +}{yields}{pi}{sup +}{pi}{sup 0}{nu}. We find a 2.2{sigma} excess in data and measure a branching fraction of B(B{sup +}{yields}{tau}{sup +}{nu})=(1.8{sub -0.8}{sup +0.9}(stat.){+-}0.4(bkg. syst.){+-}0.2(other syst.))x10{sup -4}. We calculate the product of the B meson decay constant f{sub B} and |V{sub ub}| to be f{sub B}{center_dot}|V{sub ub}|=(10.1{sub -2.5}{sup +2.3}(stat.){sub -1.5}{sup +1.2}(syst.))x10{sup -4} GeV.

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, D. Boutigny1, Y. Karyotakis1  +559 moreInstitutions (78)
TL;DR: In this paper, the authors reported results of a search for CPT and Lorentz violation in B{sup 0}-{bar B} oscillations using inclusive dilepton events from 232 million {Upsilon}(4S) {yields} B{ bar B} decays recorded by the BABAR detector at the PEP-II B Factory at SLAC.
Abstract: We report results of a search for CPT and Lorentz violation in B{sup 0}-{bar B}{sup 0} oscillations using inclusive dilepton events from 232 million {Upsilon}(4S) {yields} B{bar B} decays recorded by the BABAR detector at the PEP-II B Factory at SLAC. We find 2.8{sigma} significance, compatible with no signal, for variations in the complex CPT violation parameter z at the Earth's sidereal frequency and extract values for the quantities {Delta}a{sub {mu}} in the general Lorentz-violating standard-model extension. The spectral powers for variations in z over the frequency range 0.26 year{sup -1} to 2.1 day{sup -1} are also compatible with no signal.

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +542 moreInstitutions (79)
TL;DR: In this article, the authors proposed a method to find a monoenergetic lepton from the signal B decay using a fit to the signal lepton candidate momentum distribution in the signal bar B rest frame.
Abstract: We present searches for the leptonic decays B{sup +} {yields} {ell}{sup +}{nu} and the lepton flavor violating decays B{sup 0} {yields} {ell}{sup {+-}}{tau}{sup {-+}}, where {ell} = e, {mu}, with data collected by the BABAR experiment at SLAC. This search demonstrates a novel technique in which we fully reconstruct the accompanying {bar B} in {Upsilon}(4S) {yields} B{bar B} events, and look for a monoenergetic lepton from the signal B decay. The signal yield is extracted from a fit to the signal lepton candidate momentum distribution in the signal B rest frame. Using a data sample of approximately 378 million B{bar B} pairs (342 fb{sup -1}), we find no evidence of signal in any of the decay modes. Branching fraction upper limits of {Beta}(B{sup +} {yields} e{sup +}{nu}) < 5.2 x 10{sup -6}, {Beta}(B{sup +} {yields} {mu}{sup +}{nu}) < 5.6 x 10{sup -6}, {Beta}(B{sup 0} {yields} e{sup +}{tau}{sup -}) < 2.8 x 10{sup -5} and {Beta}(B{sup 0} {yields} {mu}{sup +}{tau}{sup -}) < 2.2 x 10{sup -5}, are obtained at 90% confidence level.

Journal ArticleDOI
B. Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +544 moreInstitutions (77)
TL;DR: In this paper, the authors search for time-integrated CP violation in the Cabibbo-suppressed decays D0/D0→π-π+π0 and D 0/D 0→K-K +π0 with both model-independent and model-dependent methods.
Abstract: Using 385fb-1 of e+e- collision data collected at center-of-mass energies around 10.6 GeV, we search for time-integrated CP violation in the Cabibbo-suppressed decays D0/D0→π-π+π0 and D0/D0→K-K+π0 with both model-independent and model-dependent methods. Measurements of the asymmetries in amplitudes of flavor states and CP eigenstates provide constraints on theories beyond the standard model, some of which predict CP violation in amplitudes at the 1% level or higher. We find no evidence of CP violation and hence no conflict with the standard model. © 2008 The American Physical Society.

Journal ArticleDOI
TL;DR: In this paper, the direction tag of the dark matter wind was measured by detecting the scintillation light created by the elastic nuclear recoils in the scattering of dark matter particles with the detector material.
Abstract: Directional detection of dark matter can provide unambiguous observation of dark matter interactions even in the presence of background. This article presents an experimental method to measure the direction tag (“head-tail”) of the dark matter wind by detecting the scintillation light created by the elastic nuclear recoils in the scattering of dark matter particles with the detector material. The technique is demonstrated by tagging the direction of the nuclear recoils created in the scattering of low-energy neutrons with CF 4 in a low-pressure time-projection chamber that is developed by the DMTPC collaboration. The measurement of the decreasing ionization rate along the recoil trajectory provides the direction tag of the incoming neutrons, and proves that the “head-tail” effect can be observed.

Journal ArticleDOI
TL;DR: In this paper, a measurement of the ratio of photon to electron production and the scintillation spectrum in a popular gas for time projection chambers, carbon tetrafluoride (CF 4 ), over the range of 200-800 nm is presented.
Abstract: This paper presents a measurement of the ratio of photon to electron production and the scintillation spectrum in a popular gas for time projection chambers, carbon tetrafluoride (CF 4 ), over the range of 200–800 nm; the ratio is measured to be 0.34 ± 0.04 . This result is of particular importance for a new generation of dark matter time projection chambers with directional sensitivity which use CF 4 as a fill gas.

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +532 moreInstitutions (81)
TL;DR: In this article, the authors measured the branching fractions of these decays; their ratio is B(B- -> Lambda(+)(c)(p) over bar pi(-))/B((B)) over bar (0) → Lambda (+)/c(p) = 15.4 +/- 1.8 +/- 0.3.
Abstract: We present an investigation of the decays B-0 -> Lambda(+)(c)(p) over bar and B- -> Lambda(+)(c)(p) over bar pi(-) based on 383 X 10(6)Y(4S) -> B (B) over bar decays recorded with the BABAR detector. We measure the branching fractions of these decays; their ratio is B(B- -> Lambda(+)(c)(p) over bar pi(-))/B((B) over bar (0) -> Lambda(+)(c)(p) over bar) = 15.4 +/- 1.8 +/- 0.3. The B- -> Lambda(+)(c)(p) over bar pi(-) process exhibits an enhancement at the Lambda(+)(c)(p) over bar threshold and is a laboratory for searches for excited charm baryon states. We observe the resonant decays B- -> Sigma(c)(2455)(0)(p) over bar and B- -> Sigma(c)(2800)(0)(p) over bar but see no evidence for B- -> Sigma(c)(2520)(0)(p) over bar. This is the first observation of the decay B- -> Sigma(c)(2800)(0)(p) over bar; however, the mass of the observed excited Sigma(0)(c) state is (2846 +/- 8 +/- 10) MeV/c(2), which is somewhat inconsistent with previous measurements. Finally, we examine the angular distribution of the B- -> Sigma(c)(2455)(0)(p) over bar decays and measure the spin of the Sigma(c)(2455)(0) baryon to be 1/2, as predicted by the quark model.

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +521 moreInstitutions (79)
TL;DR: In this paper, a time-dependent and time-integrated angular analysis of the B{sup 0} {yields} {psi}K*(892){sup 0), {pssi} K*{sub 2}(1430{Sup 0}) was performed with the final sample of about 465 million B{bar B} pairs recorded with the BABAR detector.
Abstract: We perform a time-dependent and time-integrated angular analysis of the B{sup 0} {yields} {psi}K*(892){sup 0}, {psi}K*{sub 2}(1430{sup 0}), and {psi}(K{pi}){sub S-wave}{sup 0} decays with the final sample of about 465 million B{bar B} pairs recorded with the BABAR detector. Overall, twelve parameters are measured for the vector-vector decay, nine parameters for the vector-tensor decay, and three parameters for the vector-scalar decay, including the branching fractions, CP-violation parameters, and parameters sensitive to final state interaction. We use the dependence on the K{pi} invariant mass of the interference between the scalar and vector or tensor components to resolve discrete ambiguities of the strong and weak phases. We use the time-evolution of the B {yields} {psi}K{sub S}{sup 0}{pi}{sup 0} channel to extract the CP-violation phase difference {Delta}{phi}{sub 00} = 0.28 {+-} 0.42 {+-} 0.04 between the B and {bar B} decay amplitudes. When the B {yields} {psi}K{sup {+-}}{pi}{sup {-+}} channel is included, the fractions of longitudinal polarization f{sub L} of the vector-vector and vector-tensor decay modes are measured to be 0.494 {+-} 0.034 {+-} 0.013 and 0.901{sub -0.058}{sup +0.046} {+-} 0.037, respectively. This polarization pattern requires the presence of a helicity-plus amplitude in the vector-vector decay from a presently unknown source.

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +552 moreInstitutions (79)
TL;DR: In this article, a search for lepton flavor violating decays of a tau to a lighter-mass charged lepton and an π vector meson was performed using 384.1 fb{sup -1} of e{sup +}e{sup −} annihilation data collected with the BABAR detector at the Stanford Linear Accelerator Center PEP-II storage ring.
Abstract: A search for lepton flavor violating decays of a {tau} to a lighter-mass charged lepton and an {omega} vector meson is performed using 384.1 fb{sup -1} of e{sup +}e{sup -} annihilation data collected with the BABAR detector at the Stanford Linear Accelerator Center PEP-II storage ring. No signal is found, and the upper limits on the branching ratios are determined to be {beta}({tau}{sup {+-}} {yields} e{sup {+-}}{omega}) < 1.1 x 10{sup -7} and {beta}({tau}{sup {+-}} {yields} {mu}{sup {+-}}{omega}) < 1.0 x 10{sup -7} at 90% confidence level.

Journal ArticleDOI
TL;DR: In this paper, the authors demonstrate several concepts for charge amplification in time-projection chambers that can be used in direction-sensitive dark matter search experiments, and demonstrate reconstruction of the head-tail effect for nuclear recoils above 100 kV.

Journal ArticleDOI
TL;DR: In this paper, the authors measured the rate of D-0-(D) over bar0 mixing with the observable y(CP) = (tau(K pi)/tau (KK)) - 1, where tau(KK) and tau (K pi) are, respectively, the mean lifetimes of CP-even D − 0 → K+K- and CP-mixed D − 1 → K-pi(+) decays, using a data sample of 384 fb(-1) collected by the BABAR detector at the SLAC
Abstract: We measure the rate of D-0-(D) over bar0 mixing with the observable y(CP) = (tau(K pi)/tau(KK)) - 1, where tau(KK) and tau(K pi) are, respectively, the mean lifetimes of CP-even D-0 -> K+K- and CP-mixed D-0 -> K-pi(+) 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 D-0 and (D) over bar0 decays where the initial flavor of the decaying meson is not determined, we obtain y(CP) = [1.12 +/- 0.26(stat) +/- 0.22(syst)]%, which excludes the no-mixing hypothesis at 3.3 sigma, including both statistical and systematic uncertainties. This result is in good agreement with a previous BABAR measurement of y(CP) obtained from a sample of D*(+) -> D-0 pi(+) events, where the D-0 rho decays to K-pi(+), K+K-, and pi(+)pi(-), which is disjoint with the untagged D-0 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 y(CP) = [1.16 +/- 0.22(stat) +/- 0.18(syst)]%, which excludes the no-mixing hypothesis at 4.1 sigma.

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +538 moreInstitutions (79)
TL;DR: In this paper, the authors measured the time-dependent CP asymmetry in B{sup 0} {yields} K{sub S}{sup 0}{pi-sup 0-gamma} decays for two regions of k{sub K*{gamma] invariant mass.
Abstract: The authors measure the time-dependent CP asymmetry in B{sup 0} {yields} K{sub S}{sup 0}{pi}{sup 0}{gamma} decays for two regions of K{sub S}{sup 0}-{pi}{sup 0} invariant mass, m(K{sub S}{sup 0}{pi}{sup 0}), using the final BABAR data set of 467 x 10{sup 6} B{bar B} pairs collected at the PEP-II e{sup +}e{sup -} collider at SLAC They find 339 {+-} 24 B{sup 0} {yields} K*{sup 0}{gamma} candidates and measure S{sub K*{gamma}} = -003 {+-} 029 {+-} 003 and C{sub K*{gamma}} = -014 {+-} 016 {+-} 003 In the range 11 < m(K{sub S}{sup 0}{pi}{sup 0}) < 18 GeV/c{sup 2} they find 133 {+-} 20 B{sup 0} {yields} K{sub S}{sup 0}{pi}{sup 0}{gamma} candidates and measure S{sub K{sub S}{sup 0}{pi}{sup 0}{gamma}} = -078 {+-} 059 {+-} 009 and C{sub K{sub S}{sup 0}{pi}{sup 0}{gamma}} = -036 {+-} 033 {+-} 004 The uncertainties are statistical and systematic, respectively

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +553 moreInstitutions (80)
TL;DR: In this article, a Dalitz-plot analysis of the hadronic decays of neutral B mesons to K{sup {+-}}{pi}{sup {-+}}{PI}{sup 0}.
Abstract: The authors report a Dalitz-plot analysis of the charmless hadronic decays of neutral B mesons to K{sup {+-}}{pi}{sup {-+}}{pi}{sup 0}. With a sample of (231.8 {+-} 2.6) x 10{sup 6}{Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, they measure the magnitudes and phases of the intermediate resonant and nonresonant amplitudes for B{sup 0} and {bar B}{sup 0} decays and determine the corresponding CP-averaged branching fractions and charge asymmetries. The inclusive branching fraction and CP-violating charge asymmetry are measured to be {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}) = (35.7{sub -1.5}{sup +2.6} {+-} 2.2) x 10{sup -6}, and {Alpha}{sub CP} = -0.030{sub -0.051}{sup +0.045} {+-} 0.055 where the first errors are statistical and the second systematic. They observe the decay B{sup 0} {yields} K*{sup 0}(892){pi}{sup 0} with the branching fraction {Beta}(B{sup 0} {yields} K*{sup 0}(892){pi}{sup 0}) = (3.6{sub -0.8}{sup +0.7} {+-} 0.4) x 10{sup -6}. This measurement differs from zero by 5.6 standard deviations (including the systematic uncertainties). The selected sample also contains B{sup 0} {yields} {bar D}{sup 0}{pi}{sup 0} decays where {bar D}{sup 0} {yields} K{sup +}{pi}{sup -}, and they measure {Beta}(B{sup 0} {yields} {bar D}{sup 0}{pi}{sup 0}) = (2.93 {+-} 0.17 {+-} 0.18) x 10{sup -4}.

Journal ArticleDOI
B. Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +518 moreInstitutions (80)
TL;DR: In this article, the authors measured the branching fraction B=(0.92±0.14)×10^(-6) and longitudinal polarization fraction f_L=0.75_(-0.11)± 0.05, where the first uncertainty is statistical and the second is systematic.
Abstract: We study B^0→ρ^0ρ^0 decays in a sample of 465×10^6 Υ(4S)→BB events collected with the BABAR detector at the PEP-II asymmetric-energy e^+e^- collider located at the Stanford Linear Accelerator Center (SLAC). We measure the branching fraction B=(0.92±0.32±0.14)×10^(-6) and longitudinal polarization fraction f_L=0.75_(-0.14)^(+0.11)±0.05, where the first uncertainty is statistical and the second is systematic. The evidence for the B^0→ρ^0ρ^0 signal has a significance of 3.1 standard deviations, including systematic uncertainties. We investigate the proper-time dependence of the longitudinal component in the decay and measure the CP-violating coefficients S_L^(00)=(0.3±0.7±0.2) and C_L^(00)=(0.2±0.8±0.3). We study the implication of these results for the unitarity triangle angle α.


Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +529 moreInstitutions (79)
TL;DR: In this paper, a study of hadronic transitions between mS and nS resonances based on 347.5 fb^(-1) of data taken with the BABAR detector at the PEP-II storage rings is presented.
Abstract: We present a study of hadronic transitions between Υ(mS) (m = 4, 3, 2) and Υ(nS) (n = 2, 1) resonances based on 347.5 fb^(-1) of data taken with the BABAR detector at the PEP-II storage rings. We report the first observation of Υ(4S) → ηΥ(1S) decay with a branching fraction [script B](Υ(4S) → ηΥ(1S)) = (1.96±0.06_(stat)±0.09_(syst))×10^(-4) and measure the ratio of partial widths Γ(Υ(4S) → ηΥ(1S))/Γ(Υ(4S) → π^+π^-Υ(1S))=2.41±0.40_(stat)±0.12_(syst). We set 90% CL upper limits on the ratios Γ(Υ(2S) → ηΥ(1S))/Γ(Υ(2S) → π^+π^-Υ(1S))<5.2×10^(-3) and Γ(Υ(3S) → ηΥ(1S))/Γ(Υ (3S) → π^+π^-Υ(1S))<1.9×10^(-2). We also present new measurements of the ratios Γ(Υ(4S) → π^+π^-Υ(2S))/Γ(Υ(4S) → π^+ π^-Υ(1S))=1.16±0.16_(stat)±0.14_(syst) and Γ(Υ(3S) → π^+π^-Υ(2S))/Γ(Υ(3S) → π^+ π^-Υ(1S))=0.577±0.026_(stat)±0.060_(syst).

Journal ArticleDOI
B. Aubert1, Marcella Bona, Y. Karyotakis, J. P. Lees  +539 moreInstitutions (1)
TL;DR: In this paper, the branching fraction and time-dependent CP asymmetries in B0-->J/psipi0 decays based on 466 x 10(6) Upsilon(4S)-->BB over events collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory were measured.
Abstract: We present measurements of the branching fraction and time-dependent CP asymmetries in B0-->J/psipi0 decays based on 466 x 10(6) Upsilon(4S)-->BB over events collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. We measure the CP asymmetry parameters S= -1.23+/-0.21(stat)+/-0.04(syst) and C= -0.20+/-0.19(stat)+/-0.03(syst), where the measured value of (S, C) is 4.0 standard deviations from (0, 0) including systematic uncertainties. The branching fraction is determined to be B(B0-->J/psipi0)=[1.69+/-0.14(stat)+/-0.07(syst)]x10(-5).

Journal ArticleDOI
Bernard Aubert1, Marcella Bona1, Y. Karyotakis1, J. P. Lees1  +525 moreInstitutions (79)
TL;DR: In this paper, the branching fractions of D**-decays were measured based on 417 fb-1 of data collected at the (4S) resonance with the BABAR detector at the PEP-II e+e- storage rings.
Abstract: We report a measurement of the branching fractions of D**- decays based on 417 fb-1 of data collected at the (4S) resonance with the BABAR detector at the PEP-II e+e- storage rings. Events are selected by fully reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D(*))-m(D(*)) is performed to extract the signal yields of the different D** states. We observe the D**- decay modes corresponding to the four D** states predicted by heavy quark symmetry with a significance greater than 5 standard deviations including systematic uncertainties.