-
B. Aubert,
D. Boutigny,
J.-M. Gaillard,
A. Hicheur,
Y. Karyotakis,
J. P. Lees,
P. Robbe,
V. Tisserand,
A. Palano,
A. Pompili, [......],
F. Di Lodovico,
Y. Pan,
R. Prepost,
I. J. Scott,
S. J. Sekula,
J. H. von Wimmersperg-Toeller,
S. L. Wu,
Z. Yu,
T. M. B. Kordich,
H. Neal
[show abstract]
[hide abstract]
ABSTRACT: We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at the Stanford Linear Accelerator Center. The data sample consists of 29.7 fb-1 recorded at the Υ(4S) resonance and 3.9 fb-1 off resonance. One of the neutral B mesons, which are produced in pairs at the Υ(4S), is fully reconstructed in the CP decay modes J/ψKS0, ψ(2S)KS0, χc1KS0, J/ψK*0 (K*0→KS0π0) and J/ψKL0, or in flavor-eigenstate modes involving D(*)π/ρ/a1 and J/ψK*0 (K*0→K+π-). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. A neural network tagging algorithm is used to recover events without a clear lepton or kaon tag. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. Wrong-tag probabilities, the time-difference resolution function, and the B0-B0 oscillation frequency Δmd are measured with a sample of about 6350 fully-reconstructed B0 decays in hadronic flavor-eigenstate modes. A maximum-likelihood fit to this flavor eigenstate sample finds Δmd=0.516±0.016(stat)±0.010(syst)ps-1. The value of the asymmetry amplitude sin2β is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged B0 decays in the CP-eigenstate modes. We find sin2β=0.59±0.14(stat)±0.05(syst), demonstrating that CP violation exists in the neutral B meson system. We also determine the value of the CP violation parameter |λ|=0.93±0.09(stat)±0.03(syst), which is consistent with the expectation of |λ|=1 for no direct CP violation.
Physical Review D 02/2013; 66(3). · 4.56 Impact Factor
-
B Aubert,
D Boutigny,
JM Gaillard,
A Hicheur,
Y Karyotakis,
JP Lees,
P Robbe,
V Tisserand,
A Palano,
GP Chen, [......],
Y Pan,
R Prepost,
IJ Scott,
SJ Sekula,
JH von Wimmerspeig-Toeller,
SL Wu,
Z Yu,
H Zobernig,
TMB Kordich,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: We report branching fraction measurements for exclusive decays of charged and neutral B mesons into two-body final states containing a charmonium meson. We use a sample of 22.72±0.36 million BB̅ events collected between October 1999 and October 2000 with the BABAR detector at the PEP-II storage rings at the Stanford Linear Accelerator Center. The charmonium mesons considered here are J/ψ, ψ(2S), and χc1, and the light meson in the decay is either a K, K*, or π0.
Physical Review D 02/2013; 65. · 4.56 Impact Factor
-
S Agostinelli, J Allison,
K Amako,
John Apostolakis,
H M Araújo,
P Arce,
M Asai,
D A Axen,
S Banerjee,
G Barrand, [......],
A. Walkden,
W. Wander,
H Weber,
J. P. Wellisch,
T. Wenaus,
D C Williams,
D Wright,
T Yamada,
H Yoshida,
D. Zschiesche
[show abstract]
[hide abstract]
ABSTRACT: Geant4 is a toolkit for simulating the passage of particles through matter. It includes a complete range of functionality including tracking, geometry, physics models and hits. The physics processes offered cover a comprehensive range, including electromagnetic, hadronic and optical processes, a large set of long-lived particles, materials and elements, over a wide energy range starting, in some cases, from 250 eV and extending in others to the TeV energy range. It has been designed and constructed to expose the physics models utilised, to handle complex geometries, and to enable its easy adaptation for optimal use in different sets of applications. The toolkit is the result of a worldwide collaboration of physicists and software engineers. It has been created exploiting software engineering and object-oriented technology and implemented in the C++ programming language. It has been used in applications in particle physics, nuclear physics, accelerator design, space engineering and medical physics.
Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment 02/2013; 506(3):250. · 1.21 Impact Factor
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B Aubert,
D Boutigny,
JM Gaillard,
A Hicheur,
Y Karyotakis,
JP Lees,
P Robbe,
V Tisserand,
A Palano,
GP Chen, [......],
Y Pan,
R Prepost,
IJ Scott,
SJ Sekula,
JH von Wimmersperg-Toeller,
SL Wu,
Z Yu,
H Zobernig,
TMB Kordich,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: The B0 and B+ meson lifetimes have been measured in e+e- annihilation data collected in 1999 and 2000 with the BABAR detector at center-of-mass energies near the ϒ(4S) resonance. Events are selected in which one B meson is fully reconstructed in a hadronic final state while the second B meson is reconstructed inclusively. A combined fit to the B0 and the B+ decay time difference distributions yields τB0 = 1.546±0.032(stat)±0.022(syst) ps, τB+ = 1.673±0.032(stat)±0.023(syst) ps, and τB+/τB0 = 1.082±0.026(stat)±0.012(syst).
Physical Review Letters 02/2013; 87(20). · 7.37 Impact Factor
-
BABAR Collaboration,
B Aubert,
D Boutigny,
JM Gaillard,
A Hicheur,
Y Karyotakis,
JP Lees,
P Robbe,
V Tisserand,
A Palano, [......],
R Liu,
Y Pan,
R Prepost,
IJ Scott,
SJ Sekula,
JH von Wimmersperg-Toeller,
SL Wu,
Z Yu,
TMB Kordich,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: New measurements of Ds+ and Ds*+ meson production rates from B decays and from qq̅ continuum events near the Υ(4S) resonance are presented. Using 20.8 fb-1 of data on the Υ(4S) resonance and 2.6 fb-1 off-resonance, we find the inclusive branching fractions B(B⃗Ds+X)=(10.93±0.19±0.58±2.73)% and B(B⃗Ds*+X)=(7.9±0.8±0.7±2.0)%, where the first error is statistical, the second is systematic, and the third is due to the Ds+→φπ+ branching fraction uncertainty. The production cross sections σ(e+e-→Ds+X)×B(Ds+→φπ+)=7.55±0.20±0.34pb and σ(e+e-→Ds*±X)×B(Ds+→φπ+)=5.8±0.7±0.5pb are measured at center-of-mass energies about 40 MeV below the Υ(4S) mass. The branching fractions ΣB(B⃗Ds(*)+D(*))=(5.07±0.14±0.30±1.27)% and ΣB(B⃗Ds*+D(*))=(4.1±0.2±0.4±1.0)% are determined from the Ds(*)+ momentum spectra. The mass difference m(Ds+)-m(D+)=98.4±0.1±0.3MeV/c2 is also measured.
Physical Review D 02/2013; 65(9). · 4.56 Impact Factor
-
BABAR Collaboration,
B Aubert,
D Boutigny,
JM Gaillard,
A Hicheur,
Y Karyotakis,
JP Lees,
P Robbe,
V Tisserand,
A Palano, [......],
F Di Lodovico,
Y Pan,
R Prepost,
IJ Scott,
SJ Sekula,
JH von Wimmersperg-Toeller,
SL Wu,
Z Yu,
TMB Kordich,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: Flavor oscillations of neutral B mesons have been studied in e+e- annihilation data collected with the BABAR detector at center-of-mass energies near the ϒ(4S) resonance. The data sample used for this purpose consists of events in which one B0 meson is reconstructed in a hadronic decay mode, while the flavor of the recoiling B0 is determined with a tagging algorithm that exploits the correlation between the flavor of the heavy quark and the charges of its decay products. From the time development of the observed mixed and unmixed final states, we determine the B0-B̅ 0 oscillation frequency Δmd to be 0.516±0.016(stat)±0.010(syst) ps-1.
Physical Review Letters 02/2013; 88(22). · 7.37 Impact Factor
-
BABAR Collaboration,
B Aubert,
D Boutigny,
JM Gaillard,
A Hicheur,
Y Karyotakis,
JP Lees,
P Robbe,
V Tisserand,
A Palano, [......],
F Di Lodovico,
Y Pan,
R Prepost,
IJ Scott,
SJ Sekula,
JH von Wimmersperg-Toeller,
S L Wu,
Z Yu,
TMB Kordich,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: We search for direct CP violation in charmless hadronic B decays observed in a sample of about 22.7 million BB̅ pairs collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e+e- collider. We measure the following charge asymmetries: ACP(B±→η′K±)=-0.11±0.11±0.02, ACP(B±→ωπ±)=-0.01 - 0.31 + 0.29±0.03, ACP(B±→φK±)=-0.05±0.20±0.03, ACP(B±→φK*±)=-0.43 - 0.30 + 0.36±0.06, and ACP(B0→φK*0)=0.00±0.27±0.03.
Physical Review D 02/2013; 65(5):051101. · 4.56 Impact Factor
-
BABAR Collaboration,
B Aubert,
D Boutigny,
JM Gaillard,
A Hicheur,
Y Karyotakis,
JP Lees,
P Robbe,
V Tisserand,
A Palano, [......],
F Di Lodovico,
Y Pan,
R Prepost,
IJ Scott,
SJ Sekula,
JH von Wimmersperg-Toeller,
SL Wu,
Z Yu,
TMB Kordich,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at the Stanford Linear Accelerator Center. The data sample consists of 29.7 fb-1 recorded at the Υ(4S) resonance and 3.9 fb-1 off resonance. One of the neutral B mesons, which are produced in pairs at the Υ(4S), is fully reconstructed in the CP decay modes J/ψKS0, ψ(2S)KS0, χc1KS0, J/ψK*0 (K*0→KS0π0) and J/ψKL0, or in flavor-eigenstate modes involving D(*)π/ρ/a1 and J/ψK*0 (K*0→K+π-). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. A neural network tagging algorithm is used to recover events without a clear lepton or kaon tag. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. Wrong-tag probabilities, the time-difference resolution function, and the B0-B0 oscillation frequency Δmd are measured with a sample of about 6350 fully-reconstructed B0 decays in hadronic flavor-eigenstate modes. A maximum-likelihood fit to this flavor eigenstate sample finds Δmd=0.516±0.016(stat)±0.010(syst)ps-1. The value of the asymmetry amplitude sin2β is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged B0 decays in the CP-eigenstate modes. We find sin2β=0.59±0.14(stat)±0.05(syst), demonstrating that CP violation exists in the neutral B meson system. We also determine the value of the CP violation parameter |λ|=0.93±0.09(stat)±0.03(syst), which is consistent with the expectation of |λ|=1 for no direct CP violation.
Physical Review D 02/2013; 66(3). · 4.56 Impact Factor
-
S. Schael,
R. Barate,
R. Brunelière,
I. De Bonis,
D. Decamp,
C. Goy,
S. Jézéquel,
J.-P. Lees,
F. Martin,
E. Merle, [......],
G.W. Wilson,
J.A. Wilson,
T.R. Wyatt,
S. Yamashita,
D. Zer-Zion,
L. Zivkovic,
S. Heinemeyer,
A. Pilaftsis,
G. Weiglein,
The LEP Working Group for Higgs Boson Searches
[show abstract]
[hide abstract]
ABSTRACT: The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by
the Minimal Supersymmetric standard model (MSSM). The data of the four collaborations are statistically combined and examined
for their consistency with the background hypothesis and with a possible Higgs boson signal. The combined LEP data show no
significant excess of events which would indicate the production of Higgs bosons. The search results are used to set upper
bounds on the cross-sections of various Higgs-like event topologies. The results are interpreted within the MSSM in a number
of “benchmark” models, including CP-conserving and CP-violating scenarios. These interpretations lead in all cases to large
exclusions in the MSSM parameter space. Absolute limits are set on the parameter cosβ and, in some scenarios, on the masses
of neutral Higgs bosons.
European Physical Journal C 04/2012; 47(3):547-587. · 3.63 Impact Factor
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B Aubert,
D Boutigny,
JM Gaillard,
A Hicheur,
Y Karyotakis,
JP Lees,
P Robbe,
V Tisserand,
A Palano,
GP Chen, [......],
R Prepost,
IJ Scott,
SJ Sekula,
JH von Wimmersperg-Toeller,
SL Wu,
Z Yu,
H Zobernig,
TMB Kordich,
H Neal,
BABAR Collaboration
[show abstract]
[hide abstract]
ABSTRACT: We report the result of a search for the rare decay B0→γγ in 426 fb-1 of data, corresponding to 226×106 B0B̅ 0 pairs, collected on the Υ(4S) resonance at the PEP-II asymmetric-energy e+e- collider using the BABAR detector. We use a maximum likelihood fit to extract the signal yield and observe 21-12+13 signal events with a statistical significance of 1.8σ. This corresponds to a branching fraction B(B0→γγ)=(1.7±1.1(stat.)±0.2(syst.))×10-7. Based on this result, we set a 90% confidence level upper limit of B(B0→γγ)<3.2×10-7.
Physical Review D. 01/2011; 83:11.
-
[show abstract]
[hide abstract]
ABSTRACT: Enzyme activities and bacterial populations were compared in single stage, two stage (pH=5 and 7), and two stage with cell recycling continuous cultures of mouse faecal microbiota. Results were compared to in vivo findings in the mouse caecum and faeces in order to choose the system which best models the ecology of the murine lower intestinal tract. Fecal homogenates had higher numbers of total aerobes and lactose fermenting enterics than caecal homogenates. The microbial balance of the continuous culture systems more closely resembled the faecal microbiota (the culture inoculum) than the caecal microbiota. Lactobacilli numbers were significantly lower in single stage cultures than in two stage cultures or in vivo samples. Enzyme activities were comparable between culture types, with the exception of β-glucuronidase, which was closest to the in vivo level in single stage cultures. Because no one in vitro system proved superior with regards to all the parameters studied, the choice of which system to use may be based largely on the study purpose.
07/2009; 9(3):97-108.
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B Aubert,
M Bona,
D Boutigny,
Y Karyotakis,
J P Lees,
V Poireau,
X Prudent,
V Tisserand,
A Zghiche,
J Garra Tico, [......],
X Chen,
S Dasu,
K T Flood,
J J Hollar,
P E Kutter,
Y Pan,
M Pierini,
R Prepost,
S L Wu,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: Using 383 x 10(6) BBover pairs from the BABAR data sample, we report results for branching fractions of six charged B-meson decay modes, where a charged kaon recoils against a charmless resonance decaying to KKover* or etapipi final states with mass in the range (1.2-1.8) GeV/c2. We observe a significant enhancement at the low KKover* invariant mass which is interpreted as B+-->eta(1475)K+, find evidence for the decay B+-->eta(1295)K+, and place upper limits on the decays B+-->eta(1405)K+, B+-->f1(1285)K+, B+-->f1(1420)K+, and B+-->phi(1680)K+.
Physical Review Letters 08/2008; 101(9):091801. · 7.37 Impact Factor
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B Aubert,
M Bona,
D Boutigny,
Y Karyotakis,
J P Lees,
V Poireau,
X Prudent,
V Tisserand,
A Zghiche,
J Garra Tico, [......],
X Chen,
S Dasu,
K T Flood,
J J Hollar,
P E Kutter,
Y Pan,
M Pierini,
R Prepost,
S L Wu,
H Neal
[show abstract]
[hide abstract]
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.
Physical Review Letters 08/2008; 101(8):082001. · 7.37 Impact Factor
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B. Aubert,
M. Bona,
D. Boutigny,
Y. Karyotakis,
J. P. Lees,
V. Poireau,
X. Prudent,
V. Tisserand,
A. Zghiche,
J. Garra Tico, [......],
X. Chen,
S. Dasu,
K. T. Flood,
J. J. Hollar,
P. E. Kutter,
Y. Pan,
M. Pierini,
R. Prepost,
S. L. Wu,
H. Neal
[show abstract]
[hide abstract]
ABSTRACT: The τ-→ηπ-π+π-ντ decay with the η→γγ mode is studied using 384 fb-1 of data collected by the BABAR detector. The branching fraction is measured to be (1.60±0.05±0.11)×10-4. It is found that τ-→f1(1285)π-ντ→ηπ-π+π-ντ is the dominant decay mode with a branching fraction of (1.11±0.06±0.05)×10-4. The first error on the branching fractions is statistical and the second systematic. Note that no particle identification algorithm is applied to the charged tracks to distinguish pions from kaons. In addition, a 90% confidence level upper limit on the branching fraction of the τ-→η′(958)π-ντ decay is measured to be 7.2×10-6. This last decay proceeds through a second-class current and is expected to be forbidden in the limit of isospin symmetry.
Phys. Rev. D. 06/2008; 77(11).
-
[show abstract]
[hide abstract]
ABSTRACT: Purpose: The goal of this project was to optimize angular precision in determining the principle diffusion eigenvector of prolate tensors in a diffusion tensor imaging (DTI) series, using prior knowledge of principle eigenvector direction and non‐uniform specification of gradient directions. Additionally, the effect of non‐uniform gradient distributions on fractional anisotropy (FA) was characterized. Method and Materials: Simulations were conducted, representing diffusive behavior in tissue as manifest in a DTI image series. Diffusion‐encoding gradient directions were constrained in elevation, for a prolate tensor oriented along the z‐axis. Noise was added to generate multiple measurements as per a DTI ROI analysis. Tensors were calculated as well as FA. Angular precision was quantified as the dispersion in the angle between the principle eigenvector of the prolate and the z‐axis. To confirm simulations, a phantom containing glass capillary arrays (FA=0.68) was imaged with DTI using a 3.0T GE HDx scanner. Gradient directions were specified to match simulation results. Eigenvalues, eigenvectors, and FA were calculated within an ROI. Results: Simulations identify the range of elevation angles θ=30°–40° as being most sensitive to the determination of principle eigenvector direction. This result is fairly consistent within the range of FA=0.2–0.8. Prescription of gradients within a band of elevation angles having a width of Δθ ∼40°–60° and centered at θ ∼30° can improve angular precision by 30–40%, given an uncertainty in prior eigenvector direction of <30°. FA precision using this scheme is similar to uniform gradient prescriptions, and accuracy is improved at low SNR values. Data from phantom measurements generally agree with simulation results. Conclusion: This work suggests that prior knowledge of principle eigenvector direction can improve its final determination, using gradients prescribed non‐uniformly. This technique may be useful for increasing sensitivity in these conditions (e.g., spinal lesions, determining tumor infiltration of white matter tracts).
Medical Physics 05/2008; 35(6):2906-2907. · 2.83 Impact Factor
-
B. Aubert,
M. Bona,
D. Boutigny,
Y. Karyotakis,
J. P. Lees,
V. Poireau,
X. Prudent,
V. Tisserand,
A. Zghiche,
J. Garra Tico, [......],
X. Chen,
S. Dasu,
K. T. Flood,
J. J. Hollar,
P. E. Kutter,
Y. Pan,
M. Pierini,
R. Prepost,
S. L. Wu,
H. Neal
Physical review D: Particles and fields 05/2008; 77(11):119902.
-
B Aubert,
M Bona,
D Boutigny,
Y Karyotakis,
J P Lees,
V Poireau,
X Prudent,
V Tisserand,
A Zghiche,
J Garra Tico, [......],
X Chen,
S Dasu,
K T Flood,
J J Hollar,
P E Kutter,
Y Pan,
M Pierini,
R Prepost,
S L Wu,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: We present partial branching fractions for inclusive charmless semileptonic B decays B[over ]-->X_{u}lnu[over ], and the determination of the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}|. The analysis is based on a sample of 383 x 10;{6} Upsilon(4S) decays into BB[over ] pairs collected with the BABAR detector at the SLAC PEP-II e;{+}e;{-} storage rings. We select events using the invariant mass M_{X} of the hadronic system, the invariant mass squared, q;{2}, of the lepton and neutrino pair, the kinematic variable P+, or one of their combinations. We then determine partial branching fractions in limited regions of phase space: DeltaB=(1.18+/-0.09_{stat}+/-0.07_{syst}+/-0.01_{theor})x10;{-3} (M_{X}<1.55 GeV/c;{2}), DeltaB=(0.95+/-0.10_{stat}+/-0.08_{syst}+/-0.01_{theor})x10;{-3} (P+<0.66 GeV/c), and DeltaB=(0.81+/-0.08_{stat}+/-0.07_{syst}+/-0.02_{theor})x10;{-3} (M_{X}<1.7 GeV/c;{2}, q;{2}>8 GeV;{2}/c;{4}). Corresponding values of |V_{ub}| are extracted using several theoretical calculations.
Physical Review Letters 05/2008; 100(17):171802. · 7.37 Impact Factor
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B Aubert,
M Bona,
D Boutigny,
Y Karyotakis,
J P Lees,
V Poireau,
X Prudent,
V Tisserand,
A Zghiche,
J Garra Tico, [......],
X Chen,
S Dasu,
K T Flood,
J J Hollar,
P E Kutter,
Y Pan,
M Pierini,
R Prepost,
S L Wu,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: We report on our search for decays proceeding via a tree-level b-->c quark transition in which a gluon radiates into an ss[over ] pair. We present observations of the decays B;{-}-->D_{s};{+}K;{-}pi;{-} and B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and evidence for B;{-}-->D_{s};{+}K;{-}K;{-} and set upper limits on the branching fractions for B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and B;{-}-->D_{s};{+}K;{-}K;{-} using 383x10;{6} Upsilon(4S)-->BB[over ] events collected by the BABAR detector at SLAC. We present evidence that the invariant mass distributions of D_{s};{+}K;{-} pairs from B;{-}-->D_{s};{+}K;{-}pi;{-} decays are inconsistent with the phase-space model, suggesting the presence of charm resonances lying below the D_{s};{+}K;{-} threshold.
Physical Review Letters 05/2008; 100(17):171803. · 7.37 Impact Factor
-
B. Aubert,
M. Bona,
D. Boutigny,
Y. Karyotakis,
J. P. Lees,
V. Poireau,
X. Prudent,
V. Tisserand,
A. Zghiche,
J. Garra Tico, [......],
X. Chen,
S. Dasu,
K. T. Flood,
J. J. Hollar,
P. E. Kutter,
Y. Pan,
M. Pierini,
R. Prepost,
S. L. Wu,
H. Neal
[show abstract]
[hide abstract]
ABSTRACT: We present partial branching fractions for inclusive charmless
semileptonic B decays Bmacr →Xuℓν¯, and the
determination of the Cabibbo-Kobayashi-Maskawa matrix element
|Vub|. The analysis is based on a sample of
383×106 Υ(4S) decays into B Bmacr pairs
collected with the BABAR detector at the SLAC PEP-II
e+e- storage rings. We select events using the
invariant mass MX of the hadronic system, the invariant mass
squared, q2, of the lepton and neutrino pair, the kinematic
variable P+, or one of their combinations. We then determine
partial branching fractions in limited regions of phase space:
ΔB=(1.18±0.09stat±0.07syst±0.01theor)×10-3
(MX<1.55GeV/c2),
ΔB=(0.95±0.10stat±0.08syst±0.01theor)×10-3
(P+<0.66GeV/c), and
ΔB=(0.81±0.08stat±0.07syst±0.02theor)×10-3
(MX<1.7GeV/c2,
q2>8GeV2/c4). Corresponding values
of |Vub| are extracted using several theoretical
calculations.
Physical Review Letters 04/2008; 100(17):171802. · 7.37 Impact Factor
-
B Aubert,
M Bona,
D Boutigny,
Y Karyotakis,
J P Lees,
V Poireau,
X Prudent,
V Tisserand,
A Zghiche,
J Garra Tico, [......],
X Chen,
S Dasu,
K T Flood,
J J Hollar,
P E Kutter,
Y Pan,
M Pierini,
R Prepost,
S L Wu,
H Neal
[show abstract]
[hide abstract]
ABSTRACT: We report results of a search for CPT and Lorentz violation in B(0)-B[over ](0) oscillations using inclusive dilepton events from 232 x 10(6) Upsilon(4S)-->BB[over ] decays recorded by the BABAR detector at the PEP-II B Factory at SLAC. We find 2.8sigma 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 Deltaa(micro) in the general Lorentz-violating standard-model extension. The spectral powers for variations in z over the frequency range 0.26 yr(-1) to 2.1 solar day(-1) are also compatible with no signal.
Physical Review Letters 04/2008; 100(13):131802. · 7.37 Impact Factor
