565 research outputs found
Improved Limits on decays to invisible final states
We establish improved upper limits on branching fractions for B0 decays to
final States 10 where the decay products are purely invisible (i.e., no
observable final state particles) and for final states where the only visible
product is a photon. Within the Standard Model, these decays have branching
fractions that are below the current experimental sensitivity, but various
models of physics beyond the Standard Model predict significant contributions
for these channels. Using 471 million BB pairs collected at the Y(4S) resonance
by the BABAR experiment at the PEP-II e+e- storage ring at the SLAC National
Accelerator Laboratory, we establish upper limits at the 90% confidence level
of 2.4x10^-5 for the branching fraction of B0-->Invisible and 1.7x10^-5 for the
branching fraction of B0-->Invisible+gammaComment: 8 pages, 3 postscript figures, submitted to Phys. Rev. D (Rapid
Communications
Exclusive Measurements of b -> s gamma Transition Rate and Photon Energy Spectrum
We use 429 fb of collision data collected at the
resonance with the BABAR detector to measure the radiative
transition rate of with a sum of 38 exclusive final
states. The inclusive branching fraction with a minimum photon energy of 1.9
GeV is found to be where the first uncertainty is statistical and the
second is systematic. We also measure the first and second moments of the
photon energy spectrum and extract the best fit values for the heavy-quark
parameters, and , in the kinetic and shape function
models.Comment: 18 pages, 14 pdf figures, submitted to Phys. Rev.
Measurement of the spectral function for the τ- →k-KSντ decay
open238siThe decay tau(-) -> K- K(S)v(tau) has been studied using 430 x 10(6) e(+) e(-) -> tau(+) tau(-) events produced at a center-of-mass energy around 10.6 GeV at the PEP-II collider and studied with the BABAR detector. The mass spectrum of the K- K-S system has been measured and the spectral function has been obtained. The measured branching fraction B(tau(-) -> K- K(S)v(tau)) = (0.739 +/- 0.011 (stat) +/- 0.020 (syst)) x 10(-3) is found to be in agreement with earlier measurements.openLees, J.P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Brown, D.N.; Kolomensky, Yu.G.; Fritsch, M.; Koch, H.; Schroeder, T.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; So, R.Y.; Blinov, V.E.; Buzykaev, A.R.; Druzhinin, V.P.; Golubev, V.B.; Kozyrev, E.A.; Kravchenko, E.A.; Onuchin, A.P.; Serednyakov, S.I.; Skovpen, Yu.I.; Solodov, E.P.; Todyshev, K.Yu.; Lankford, A.J.; Gary, J.W.; Long, O.; Eisner, A.M.; Lockman, W.S.; Panduro Vazquez, W.; Chao, D.S.; Cheng, C.H.; Echenard, B.; Flood, K.T.; Hitlin, D.G.; Kim, J.; Li, Y.; Miyashita, T.S.; Ongmongkolkul, P.; Porter, F.C.; Röhrken, M.; Huard, Z.; Meadows, B.T.; Pushpawela, B.G.; Sokoloff, M.D.; Sun, L.; Smith, J.G.; Wagner, S.R.; Bernard, D.; Verderi, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Fioravanti, E.; Garzia, I.; Luppi, E.; Santoro, V.; Calcaterra, A.; De Sangro, R.; Finocchiaro, G.; Martellotti, S.; Patteri, P.; Peruzzi, I.M.; Piccolo, M.; Rotondo, M.; Zallo, A.; Passaggio, S.; Patrignani, C.; Lacker, H.M.; Bhuyan, B.; Mallik, U.; Chen, C.; Cochran, J.; Prell, S.; Gritsan, A.V.; Arnaud, N.; Davier, M.; Le Diberder, F.; Lutz, A.M.; Wormser, G.; Lange, D.J.; Wright, D.M.; Coleman, J.P.; Gabathuler, E.; Hutchcroft, D.E.; Payne, D.J.; Touramanis, C.; Bevan, A.J.; Di Lodovico, F.; Sacco, R.; Cowan, G.; Banerjee, Sw.; Brown, D.N.; Davis, C.L.; Denig, A.G.; Gradl, W.; Griessinger, K.; Hafner, A.; Schubert, K.R.; Barlow, R.J.; Lafferty, G.D.; Cenci, R.; Jawahery, A.; Roberts, D.A.; Cowan, R.; Robertson, S.H.; Seddon, R.M.; Dey, B.; Neri, N.; Palombo, F.; Cheaib, R.; Cremaldi, L.; Godang, R.; Summers, D.J.; Taras, P.; De Nardo, G.; Sciacca, C.; Raven, G.; Jessop, C.P.; Losecco, J.M.; Honscheid, K.; Kass, R.; Gaz, A.; Margoni, M.; Posocco, M.; Simi, G.; Simonetto, F.; Stroili, R.; Akar, S.; Ben-Haim, E.; Bomben, M.; Bonneaud, G.R.; Calderini, G.; Chauveau, J.; Marchiori, G.; Ocariz, J.; Biasini, M.; Manoni, E.; Rossi, A.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Casarosa, G.; Chrzaszcz, M.; Forti, F.; Giorgi, M.A.; Lusiani, A.; Oberhof, B.; Paoloni, E.; Rama, M.; Rizzo, G.; Walsh, J.J.; Zani, L.; Smith, A.J.S.; Anulli, F.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Pilloni, A.; Piredda, G.; Bünger, C.; Dittrich, S.; Grünberg, O.; Heß, M.; Leddig, T.; Voß, C.; Waldi, R.; Adye, T.; Wilson, F.F.; Emery, S.; Vasseur, G.; Aston, D.; Cartaro, C.; Convery, M.R.; Dorfan, J.; Dunwoodie, W.; Ebert, M.; Field, R.C.; Fulsom, B.G.; Graham, M.T.; Hast, C.; Innes, W.R.; Kim, P.; Leith, D.W.G.S.; Luitz, S.; Macfarlane, D.B.; Muller, D.R.; Neal, H.; Ratcliff, B.N.; Roodman, A.; Sullivan, M.K.; Va'Vra, J.; Wisniewski, W.J.; Purohit, M.V.; Wilson, J.R.; Randle-Conde, A.; Sekula, S.J.; Ahmed, H.; Bellis, M.; Burchat, P.R.; Puccio, E.M.T.; Alam, M.S.; Ernst, J.A.; Gorodeisky, R.; Guttman, N.; Peimer, D.R.; Soffer, A.; Spanier, S.M.; Ritchie, J.L.; Schwitters, R.F.; Izen, J.M.; Lou, X.C.; Bianchi, F.; De Mori, F.; Filippi, A.; Gamba, D.; Lanceri, L.; Vitale, L.; Martinez-Vidal, F.; Oyanguren, A.; Albert, J.; Beaulieu, A.; Bernlochner, F.U.; King, G.J.; Kowalewski, R.; Lueck, T.; Nugent, I.M.; Roney, J.M.; Sobie, R.J.; Tasneem, N.; Gershon, T.J.; Harrison, P.F.; Latham, T.E.; Prepost, R.; Wu, S.L.Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Brown, D. N.; Kolomensky, Yu. G.; Fritsch, M.; Koch, H.; Schroeder, T.; Hearty, C.; Mattison, T. S.; Mckenna, J. A.; So, R. Y.; Blinov, V. E.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Kozyrev, E. A.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Lankford, A. J.; Gary, J. W.; Long, O.; Eisner, A. M.; Lockman, W. S.; Panduro Vazquez, W.; Chao, D. S.; Cheng, C. H.; Echenard, B.; Flood, K. T.; Hitlin, D. G.; Kim, J.; Li, Y.; Miyashita, T. S.; Ongmongkolkul, P.; Porter, F. C.; Röhrken, M.; Huard, Z.; Meadows, B. T.; Pushpawela, B. G.; Sokoloff, M. D.; Sun, L.; Smith, J. G.; Wagner, S. R.; Bernard, D.; Verderi, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Fioravanti, E.; Garzia, I.; Luppi, E.; Santoro, V.; Calcaterra, A.; De Sangro, R.; Finocchiaro, G.; Martellotti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rotondo, M.; Zallo, A.; Passaggio, S.; Patrignani, C.; Lacker, H. M.; Bhuyan, B.; Mallik, U.; Chen, C.; Cochran, J.; Prell, S.; Gritsan, A. V.; Arnaud, N.; Davier, M.; Le Diberder, F.; Lutz, A. M.; Wormser, G.; Lange, D. J.; Wright, D. M.; Coleman, J. P.; Gabathuler, E.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Di Lodovico, F.; Sacco, R.; Cowan, G.; Banerjee, Sw.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Gradl, W.; Griessinger, K.; Hafner, A.; Schubert, K. R.; Barlow, R. J.; Lafferty, G. D.; Cenci, R.; Jawahery, A.; Roberts, D. A.; Cowan, R.; Robertson, S. H.; Seddon, R. M.; Dey, B.; Neri, N.; Palombo, F.; Cheaib, R.; Cremaldi, L.; Godang, R.; Summers, D. J.; Taras, P.; De Nardo, G.; Sciacca, C.; Raven, G.; Jessop, C. P.; Losecco, J. M.; Honscheid, K.; Kass, R.; Gaz, A.; Margoni, M.; Posocco, M.; Simi, G.; Simonetto, F.; Stroili, R.; Akar, S.; Ben-Haim, E.; Bomben, M.; Bonneaud, G. R.; Calderini, G.; Chauveau, J.; Marchiori, G.; Ocariz, J.; Biasini, M.; Manoni, E.; Rossi, A.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Casarosa, G.; Chrzaszcz, M.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Oberhof, B.; Paoloni, E.; Rama, M.; Rizzo, G.; Walsh, J. J.; Zani, L.; Smith, A. J. S.; Anulli, F.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Pilloni, A.; Piredda, G.; Bünger, C.; Dittrich, S.; Grünberg, O.; Heß, M.; Leddig, T.; Voß, C.; Waldi, R.; Adye, T.; Wilson, F. F.; Emery, S.; Vasseur, G.; Aston, D.; Cartaro, C.; Convery, M. R.; Dorfan, J.; Dunwoodie, W.; Ebert, M.; Field, R. C.; Fulsom, B. G.; Graham, M. T.; Hast, C.; Innes, W. R.; Kim, P.; Leith, D. W. G. S.; Luitz, S.; Macfarlane, D. B.; Muller, D. R.; Neal, H.; Ratcliff, B. N.; Roodman, A.; Sullivan, M. K.; Va'Vra, J.; Wisniewski, W. J.; Purohit, M. V.; Wilson, J. R.; Randle-Conde, A.; Sekula, S. J.; Ahmed, H.; Bellis, M.; Burchat, P. R.; Puccio, E. M. T.; Alam, M. S.; Ernst, J. A.; Gorodeisky, R.; Guttman, N.; Peimer, D. R.; Soffer, A.; Spanier, S. M.; Ritchie, J. L.; Schwitters, R. F.; Izen, J. M.; Lou, X. C.; Bianchi, F.; De Mori, F.; Filippi, A.; Gamba, D.; Lanceri, L.; Vitale, L.; Martinez-Vidal, F.; Oyanguren, A.; Albert, J.; Beaulieu, A.; Bernlochner, F. U.; King, G. J.; Kowalewski, R.; Lueck, T.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Tasneem, N.; Gershon, T. J.; Harrison, P. F.; Latham, T. E.; Prepost, R.; Wu, S. L
Measurement of decay rate and parameters at KEDR
Using the inclusive photon spectrum based on a data sample collected at the
peak with the KEDR detector at the VEPP-4M collider, we
measured the rate of the radiative decay as well
as mass and width. Taking into account an asymmetric photon
lineshape we obtained keV, MeV/, MeV.Comment: 6 pages, 3 figure
Precise measurement of and between 1.84 and 3.72 GeV at the KEDR detector
The present work continues a series of the KEDR measurements of the value
that started in 2010 at the VEPP-4M collider. By combining new data
with our previous results in this energy range we measured the values of
and at nine center-of-mass energies between 3.08 and 3.72
GeV. The total accuracy is about or better than at most of energy
points with a systematic uncertainty of about . Together with the
previous precise measurement at KEDR in the energy range 1.84-3.05 GeV, it
constitutes the most detailed high-precision measurement near the
charmonium production threshold.Comment: arXiv admin note: text overlap with arXiv:1610.02827 and substantial
text overlap with arXiv:1510.0266
Measurement of B(J/psi->eta_c gamma) at KEDR
We present a study of the inclusive photon spectrum from 6.3 million J/psi
decays collected with the KEDR detector at the VEPP-4M e+e- collider. We
measure the branching fraction of the radiative decay J/psi -> eta_c gamma,
eta_c width and mass. Taking into account an asymmetric photon line shape we
obtain: M(eta_c) = (2978.1 +- 1.4 +- 2.0) MeV/c^2, Gamma(eta_c) = (43.5 +- 5.4
+- 15.8) MeV, B(J/psi->eta_c gamma) = (2.59 +- 0.16 +- 0.31)%$.Comment: 6 pages, 1 figure. To be published in the proceedings of the 4th
International Workshop on Charm Physics (Charm2010), October 21-24, 2010,
IHEP, Beijin
Measurement of ISR-FSR interference in the processes e+ e- --> mu+ mu- gamma and e+ e- --> pi+ pi- gamma
Charge asymmetry in 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
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. The asymmetry is determined as
afunction of the invariant mass of the final-state tracks from production
threshold to a few GeV/c2. 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.Comment: 32 pages,29 figures, to be submitted to Phys. Rev.
Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-
In a sample of 471 million BB events collected with the BABAR detector at the
PEP-II e+e- collider we study the rare decays B -> K(*) l+ l-, where l+ l- is
either e+e- or mu+mu-. We report results on partial branching fractions and
isospin asymmetries in seven bins of di-lepton mass-squared. We further present
CP and lepton-flavor asymmetries for di-lepton masses below and above the J/psi
resonance. We find no evidence for CP or lepton-flavor violation. The partial
branching fractions and isospin asymmetries are consistent with the Standard
Model predictions and with results from other experiments.Comment: 16 pages, 14 figures, accepted by Phys. Rev.
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