|   | 
Details
   web
Records
Author DELPHI Collaboration (Abdallah, J. et al); Costa, M.J.; Ferrer, A.; Fuster, J.; Garcia, C.; Oyanguren, A.; Perepelitsa, V.; Salt, J.; Tortosa, P.
Title A study of the b-quark fragmentation function with the DELPHI detector at LEP I and an averaged distribution obtained at the Z Pole Type Journal Article
Year 2011 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 71 Issue 2 Pages 1557 - 29pp
Keywords
Abstract The nature of b-quark jet hadronisation has been investigated using data taken at the Z peak by the DELPHI detector at LEP. Two complementary methods are used to reconstruct the energy of weakly decaying b-hadrons, E-B(weak). The average value of x(B)(weak) = E-B(weak)/E-beam is measured to be 0.699 +/- 0.011. The resulting x(B)(weak) distribution is then analysed in the framework of two choices for the perturbative contribution (parton shower and Next to Leading Log QCD calculation) in order to extract measurements of the non-perturbative contribution to be used in studies of b-hadron production in other experimental environments than LEP. In the parton shower framework, data favour the Lund model ansatz and corresponding values of its parameters have been determined within PYTHIA 6.156 from DELPHI data: a = 1.84(-0.21)(+0.23) and b = 0.642(-0.063)(+0.073) GeV-2, with a correlation factor rho = 92.2%. Combining the data on the b-quark fragmentation distributions with those obtained at the Z peak by ALEPH, OPAL and SLD, the average value of x(B)(weak) is found to be 0.7092 +/- 0.0025 and the non-perturbative fragmentation component is extracted. Using the combined distribution, a better determination of the Lund parameters is also obtained: a = 1.48(-0.10)(+0.11) and b = 0.509(-0.023)(+0.024) GeV-2, with a correlation factor rho = 92.6%.
Address [Lamsa, J.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA, Email: timmerma@mail.cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes ISI:000291694100016 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 655
Permanent link to this record
 

 
Author BABAR Collaboration (Lees, J.P. et al); Lopez-March, N.; Martinez-Vidal, F.; Oyanguren, A.
Title Cross sections for the reactions e(+)e(-) -> K+K-pi(+)pi(-), K+K-pi(0)pi(0), and K+K-K+K- measured using initial-state radiation events Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 86 Issue 1 Pages 012008 - 34pp
Keywords
Abstract We study the processes e(+)e(-) -> K+K-pi(+)pi(-)gamma, K+K-pi(0)pi(0)gamma, and K+K-K+K-gamma, where the photon is radiated from the initial state. About 84000, 8000, and 4200 fully reconstructed events, respectively, are selected from 454 fb(-1) of BABAR data. The invariantmass of the hadronic final state defines the e(+)e(-) center-of- mass energy, so that the K+K-pi(+)pi(-)gamma data can be compared with direct measurements of the e(+)e(-) -> K+K-pi(+)pi(-) reaction. No directmeasurements exist for the e(+)e(-) -> K+K-pi(0)pi(0) or e(+)e(-) -> K+K-K+K- reactions, andwe present an update of our previous result based on a data sample that is twice as large. Studying the structure of these events, we find contributions froma number of intermediate states and extract their cross sections. In particular, we perform a more detailed study of the e(+)e(-) -> phi(1020)pi pi gamma reaction and confirm the presence of the Y(2175) resonance in the phi(1020)integral(0)(980) and K+K-integral(0)(980) modes. In the charmonium region, we observe the J/psi in all three final states and in several intermediate states, as well as the psi(2S) in some modes, and measure the corresponding products of branching fraction and electron width.
Address [Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.] Univ Savoie, CNRS IN2P3, LAPP, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000306929300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1128
Permanent link to this record
 

 
Author BABAR Collaboration (Lees, J.P. et al); Lopez-March, N.; Martinez-Vidal, F.; Oyanguren, A.
Title Study of radiative bottomonium transitions using converted photons Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 7 Pages 072002 - 17pp
Keywords
Abstract We use (111 +/- 1) million Gamma(3S) and (89 +/- 1) million Gamma(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 Gamma(3S) -> gamma chi b(0,2)(1P) decay, make precise measurements of the branching fractions for chi b(1,2)(1P, 2P) -> gamma Gamma(1S) and chi b(1,2)(2P) -> gamma Gamma(2S) decays, and search for radiative decay to the eta(b)(1S) and eta(b)(2S) states.
Address [Lees, JP; Poireau, V; Prencipe, E; Tisserand, V] Univ Savoie, Lab Annecy Le Vieux Phys Particules LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000296527100002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 795
Permanent link to this record
 

 
Author BABAR Collaboration (Lees, J.P. et al); Lopez-March, N.; Martinez-Vidal, F.; Oyanguren, A.
Title Amplitude analysis of B0 -> K+ pi- pi0 and evidence of direct CP violation in B -> K * pi decays Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 11 Pages 112010 - 21pp
Keywords
Abstract We analyze the decay B-0 -> K+ pi(-) pi(0) with a sample of 4.54 x 10(8) B (B) over bar events collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, and extract the complex amplitudes of seven interfering resonances over the Dalitz plot. These results are combined with amplitudes measured in B-0 -> K-S(0)pi(+)pi(-) decays to construct isospin amplitudes from B-0 -> K* pi and B-0 -> rho K decays. We measure the phase of the isospin amplitude Phi(3/2), useful in constraining the Cabibbo-Kobayashi-Maskawa unitarity triangle angle gamma and evaluate a CP rate asymmetry sum rule sensitive to the presence of new physics operators. We measure direct CP violation in B-0 -> K*(+) pi(-) decays at the level of 3 sigma when measurements from both B-0 -> K+ pi(-) pi(0) and B-0 -> K-S(0) pi(+) pi(-) decays are combined.
Address [Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.] Univ Savoie, CNRS IN2P3, Lab Annecy Le Vieux Phys Particules LAPP, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000292240300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 661
Permanent link to this record
 

 
Author BABAR Collaboration (Lees, J.P. et al); Lopez-March, N.; Martinez-Vidal, F.; Oyanguren, A.
Title Study of dipion bottomonium transitions and search for the h(b)(1P) state Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 1 Pages 011104 - 9pp
Keywords
Abstract We study inclusive dipion decays using a sample of 108 x 10(6)Y(3S) events recorded with the BABAR detector. We search for the decay mode Y(3S) -> pi(+)pi(-) h(b)(1P) and find no evidence for the bottomonium spin-singlet state h(b)(1P) in the invariant mass distribution recoiling against the pi(+)pi(-) system. Assuming the h(b)(1P) mass to be 9.900 GeV/c(2), we measure the upper limit on the branching fraction B[Y(3S) -> pi(+)pi(-) h(b)(1P)] < 1.2 x 10(-4), at 90% confidence level. We also investigate the chi(bJ)(2P) -> pi(+)pi(-) chi(bJ)(1P), Y(3S) -> pi(+)pi(-) Y(2S), and Y(2S) -> pi(+)pi(-) Y(1) dipion transitions and present an improved measurement of the branching fraction of the Y(3S) -> pi(+)pi(-) Y(2S) decay and of the Y(3S) – Y(2S) mass difference.
Address [Lees, JP; Poireau, V; Tisserand, V] Univ Savoie, Lab Annecy le Vieux Phys Particules LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000293182000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 710
Permanent link to this record