Measurements of branching fractions for electromagnetic transitions involving the $χ_{bJ}(1P)$ states
The CLEO Collaboration, M. Kornicer, R. E. Mitchell, C. M. Tarbert, D. Besson, T. K. Pedlar, D. Cronin-Hennessy, J. Hietala, P. Zweber, S. Dobbs, Z. Metreveli, … 展开作者
The CLEO Collaboration, M. Kornicer, R. E. Mitchell, C. M. Tarbert, D. Besson, T. K. Pedlar, D. Cronin-Hennessy, J. Hietala, P. Zweber, S. Dobbs, Z. Metreveli, K. K. Seth, A. Tomaradze, T. Xiao, S. Brisbane, L. Martin, A. Powell, P. Spradlin, G. Wilkinson, H. Mendez, J. Y. Ge, D. H. Miller, I. P. J. Shipsey, B. Xin, G. S. Adams, D. Hu, B. Moziak, J. Napolitano, K. M. Ecklund, J. Insler, H. Muramatsu, C. S. Park, L. J. Pearson, E. H. Thorndike, F. Yang, S. Ricciardi, C. Thomas, M. Artuso, S. Blusk, R. Mountain, T. Skwarnicki, S. Stone, J. C. Wang, L. M. Zhang, G. Bonvicini, D. Cinabro, A. Lincoln, M. J. Smith, P. Zhou, J. Zhu, P. Naik, J. Rademacker, D. M. Asner, K. W. Edwards, K. Randrianarivony, G. Tatishvili, R. A. Briere, H. Vogel, P. U. E. Onyisi, J. L. Rosner, J. P. Alexander, D. G. Cassel, S. Das, R. Ehrlich, L. Fields, L. Gibbons, S. W. Gray, D. L. Hartill, B. K. Heltsley, D. L. Kreinick, V. E. Kuznetsov, J. R. Patterson, D. Peterson, D. Riley, A. Ryd, A. J. Sadoff, X. Shi, W. M. Sun, J. Yelton, P. Rubin, N. Lowrey, S. Mehrabyan, M. Selen, J. Wiss, J. Libby
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22 pages, 6 figures, version published in Physical Review D
Using 9.32, 5.88 million Upsilon(2S,3S) decays taken with the CLEO-III detector, we obtain five product branching fractions for the exclusive processes Upsilon(2S) => gamma chi_{b0,1,2}(1P) => gamma gamma Upsilon(1S) and Upsilon(3S) => gamma chi_{b1,2}(1P) => gamma gamma Upsilon(1S). We observe the transition chi_{b0}(1P) => gamma Upsilon(1S) for the first time. Using the known branching fractions for B[Upsilon(2S) => gamma chi_{bJ}(1P)], we extract values for B[chi_{bJ}(1P) => gamma Upsilon(1S)] for J=0, 1, 2. In turn, these values can be used to unfold the Upsilon(3S) product branching fractions to obtain values for B[Upsilon(3S) => gamma chi_{b1,2}(1P) for the first time individually. Comparison of these with each other and with the branching fraction B[Upsilon(3S) => gamma chi_{b0}] previously measured by CLEO provides tests of relativistic corrections to electric dipole matrix elements.
We report a measurement of the ratios of the decay rates of the B^+, B^0 and B^0_s mesons into exclusive final states containing a J/psi meson. The final states were selected from 19.6 pb^{-1} of p-pbar collisions recorded by the Collider Detector at Fermilab. These data are interpreted to determine the bquark fragmentation fractions f_u, f_d and f_s. We also determine the branching fractions for the decay modes B^+ --> J/psi K^+, B^+ --> J/psi K^*(892)^+, B^0 --> J/psi K^0, B^0 --> J/psi K^*(892)^0 and B_s^0 --> J/psi phi(1020). We discuss the implications of these measurements to B meson dec…
We measure the branching ratios of the Cabibbo-suppressed decays $Λ^+_c$ $\to$ $Λ$ $K^+$ and $Λ^+_c$ $\to$ $Σ^{0}$ $K^+$ %(measured with improved accuracy). relative to the Cabibbo-favored decay modes $Λ^+_c$ $\to$ $Λ$ $π^+$ and $Λ^+_c$ $\to$ $Σ^{0}$ $π^+$ to be $ 0.044 \pm 0.004 (\textnormal{stat.}) \pm 0.003 \ (\textnormal{syst.})$ and $ 0.039 \pm 0.005 (\textnormal{stat.}) \pm 0.003 (\textnormal{syst.})$, respectively. We set an upper limit on the branching ratio at 90 % confidence level for $Λ^+_c$ $\to$ $Λ$ $K^+ π^+ π^-$ to be $ 4.1 \times 10^{-2}$ relative to $Λ^+_c$ $\to$ $Λ$ $π^+$ and …
Heavy-hadron chiral perturbation theory (HH$χ$PT) is applied to the decays of the even-parity charmed strange mesons, D_{s0}(2317) and D_{s1}(2460). Heavy-quark spin symmetry predicts the branching fractions for the three electromagnetic decays of these states to the ground states D_s and D_s^* in terms of a single parameter. The resulting predictions for two of the branching fractions are significantly higher than current upper limits from the CLEO experiment. Leading corrections to the branching ratios from chiral loop diagrams and spin-symmetry violating operators in the HH$χ$PT Lagrangian …
The CLAS detector was used to obtain the first ever measurement of the electromagnetic decay of the $Σ^{*+}(1385)$ from the reaction $γp \to K^0 Σ^{*+}(1385)$. A real photon beam with a maximum energy of 3.8 GeV was incident on a liquid-hydrogen target, resulting in the photoproduction of the kaon and $Σ^*$ hyperon. Kinematic fitting was used to separate the reaction channel from the background processes. The fitting algorithm exploited a new method to kinematically fit neutrons in the CLAS detector, leading to the partial width measurement of $250.0\pm56.9(stat)^{+34.3}_{-41.2}(sys)$ keV. A U…
Using the data sample of 10.5 fb-1 collected by the Belle detector, we searched for two-body charmless decays involving vector mesons. The clear signal signature of B+ -> phi K+ is seen and its branching fraction is measured to be (1.39+.32-.30 +- 0.2) X 10-5. The evidence for B+ -> rho pi+, B0 -> rho- pi+ and B+ -> phi K*+ is reported and their branching fractions are determined. No significant signals are observed for B0 -> phi K0S, -> phi K*0, -> rho- K+, B+ -> rho K+, -> omega pi+ and -> omega K+ only the 90% C.L. upper limits are given.
Using a sample of 3.08 million psi(2S) decays collected at sqrt{s} = 3.686 GeV with the CLEO detector at the Cornell Electron Storage Ring, we have measured the branching fractions for psi(2S) decays to pseudoscalar pairs pi+pi-, K+K-, and KsKl. We obtain B(psi(2S) -> pi+pi-) < 2.1 x 10^{-5} (90% C.L.), B(psi(2S) -> K+K-) = (6.3 +- 0.6(stat) +- 0.3(syst)) x 10^{-5}, and B(psi(2S) -> KsKl) = (5.8 +- 0.8(stat) +- 0.4(syst)) x 10^{-5}. The branching fractions allow extraction of the relative phase Delta = (95 +- 15) degrees and strength ratio R = (2.5 +- 0.4) of the three-gluon and one-photon amp…
We present some recent results in hadronic decays and cross-section measurements at Psi(3770) from CLEO collaboration. They include measurement of absolute hadronic branching fractions of D mesons and e+e- to DDbar cross-sections, inclusive production of eta, eta', phi in D decays, branching fractions of D+ to K0_{S,L} pi+ and eta pi+, Psi(3770) non-DDbar decays, and timelike electromagnetic form factors of pion, kaon and proton. These results are based on 55.8 pb-1 and 281 pb-1 at Psi(3770), and other data samples collected by the CLEO-c detector at the Cornell Electron Storage Ring (CESR).
The branching fractions of D_s meson decays serve to normalize many measurements of processes involving charm quarks. Using 298 /pb of e+ e- collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for eight D_s decays with a double tag technique. In particular we determine the branching fraction B(D_s -> K- K+ pi+) = (5.50 +- 0.23 +- 0.16)%, where the uncertainties are statistical and systematic respectively. We also provide partial branching fractions for kinematic subsets of the K- K+ pi+ decay mode.
We use $(121\pm1)$ million $Υ(3S)$ and $(98\pm1)$ million $Υ(2S)$ mesons recorded by the BABAR detector at the PEP-II $e^+e^-$ collider at SLAC to perform a study of radiative transitions involving the $χ_{b\mathrm{J}}(1P,2P)$ states in exclusive decays with $μ^+μ^-γγ$ final states. We reconstruct twelve channels in four cascades using two complementary methods. In the first we identify both signal photon candidates in the Electromagnetic Calorimeter (EMC), employ a calorimeter timing-based technique to reduce backgrounds, and determine branching-ratio products and fine mass splittings. These …
Using data samples collected at sqrt(s) = 3.686GeV and 3.650GeV by the BESII detector at the BEPC, the branching fraction of psi(2S) -> 3(pi+pi-) is measured to be [4.83 +- 0.38(stat) +- 0.69(syst)] x 10^-4, and the relative branching fraction of J/psi -> 2(pi+pi-) to that of J/psi -> mu+mu- is measured to be [5.86 +- 0.19(stat) +- 0.39(syst)]% via psi(2S) -> (pi+pi-)J/psi, J/psi -> 2(pi+pi-). The electromagnetic form factor of 3(pi+pi-) is determined to be 0.21 +- 0.02 and 0.20 +- 0.01 at sqrt(s) = 3.686GeV and 3.650GeV, respectively.
We report a study of $τ$ lepton decays involving $\Ks$ with a 669 fb$^{-1}$ data sample accumulated with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider. The branching fractions have been measured for the $\tauTO \piKs ν_τ$, $\KKs ν_τ$, $\piKspizero ν_τ$, $\KKspizero ν_τ$, $\piKsKs ν_τ$ and $\piKsKspizero ν_τ$ decays. We also provide the unfolded mass spectra for $\tauTO \piKspizero ν_τ$ and $\tauTO \KKspizero ν_τ$.
Semileptonic and leptonic B decays are analyzed in the framework of the relativistic quark model. Special attention is payed to the decays involving $τ$ lepton. It is found that the calculated particular decay branching fractions are consistent with available experimental data within error bars. However, the predicted and recently measured ratios $R(D^{(*)})$ of the $B\to D^{(*)}τν_τ$ and $B\to D^{(*)}lν_l$ branching fractions differ by 1.75$σ$ for $R(D)$ and by 2.4$σ$ for $R(D^*)$.
We study the decay of Ds meson into final states involving a Ks and report the discovery of Cabibbo suppressed decay modes Ds -> Kspi-pi+pi+ (179 +/- 36 events) and Ds -> Kspi+ (113 +/-26 events). The branching ratios for the new modes are Gamma(Ds -> Kspi-pi+pi+)/Gamma(Ds -> KsK-pi+pi+) = 0.18 +/- 0.04 +/- 0.05 and Gamma(Ds -> Kspi+)/Gamma(Ds -> KsK+) = 0.104 +/- 0.024 +/- 0.013.
We present a preliminary determination of the inclusive branching fraction for the rare radiative penguin transition B -> X_{s} gamma. The measurement is based on a data sample of 60 million BB pairs collected between 1999 and 2001 with the BaBar detector at the PEPII asymmetric-energy e+e- B Factory at SLAC. We study events containing a high-energy photon from one B (or Bbar) decay and a tagging primary lepton from the decay of the other B meson. By this means, we are able to reduce a significant component of the background without introduction of model dependent uncertainties in the event se…
The photon spectrum in the inclusive electromagnetic radiative decays of the $B$ meson, $B \to X_{s} γ$ plus $B \to X_{d} γ$, is studied using a data sample of $(382.8 \pm 4.2) \times 10^6$ $Υ(4S) \to B\overli\ ne{B}$ decays collected by the \babar\ experiment at SLAC. The spectrum is used to extract the branching fraction ${\cal B}(B \to X_{s} γ)=(3.21 \pm 0.33)\times 10^{-4}$ for $E_γ>1.8 \gev$ and the direct CP asymmetry $A_{CP}(B \to X_{s+d} γ)=0.057 \pm 0.063$. The effects of detector resolution and Doppler smearing are unfolded to measure the photon energy spectrum in the $B$ meson rest …
We study the decay of $D^0$ and $D^+_s$ mesons into five-body final states including a $K_S^0$ and report the discovery of the decay mode $D_s^+\to K_S^0 K_S^0π^+π^+π^-$. The branching ratio for the new mode is {${Γ(D_s^+\to K_S^0K_S^0π^+π^-π^+)} \over {Γ(D_s^+\to K_S^0K^-π^+π^+)}$} = 0.102$\pm0.029\pm$0.029. We also determine the branching ratio of {${Γ(D^0\to K_S^0π^+π^+π^-π^-)} \over {Γ(D^0 \to K_S^0π^+π^-)}$} = 0.095$\pm0.005\pm$0.007 as well as an upper limit for {${Γ(D^0\to K_S^0K^-π^+π^+π^-)} \over {Γ(D^0\to K_S^0π^+π^+π^-π^-)}$} $<$ 0.054 (90% CL). An analysis of the resonant substruct…
Cross sections and form factors for $\ee \to \wpi$, $ρη$, and $ρ\etap$ at center of mass energies of 3.650, 3.686, and 3.773 GeV are measured using data samples collected with the BESII detector at the BEPC. Also, the branching fractions of $ψ(2S) \rar \wpi$, $ρη$, and $ρ\etap$ are determined to be $(1.87^{+0.68}_{-0.62}\pm0.28)\times 10^{-5}$, $(1.78^{+0.67}_{-0.62}\pm0.17)\times 10^{-5}$, and $(1.87^{+1.64}_{-1.11}\pm0.33)\times10^{-5}$, respectively.
We study two-body $B_{(c)}\to M_c(π,K)$ and semileptonic $B_{c}\to M_c\ell^-\bar ν_\ell$ decays with $M_c=(J/ψ,X_c^0)$, where $X_c^0\equiv X^0(3872)$ is regarded as the tetraquark state of $c\bar cu\bar u(d\bar d)$. With the decay constant $f_{X_c^0}=(234\pm 52)$~MeV determined from the data, we predict that ${\cal B}(B^-\to X_c^0π^-)=(11.5\pm 5.7)\times 10^{-6}$, ${\cal B}(\bar B^0\to X_c^0\bar K^0)=(2.1\pm 1.0)\times 10^{-4}$, and ${\cal B}(\bar B^0_s\to X_c^0\bar K^0)=(11.4\pm 5.6)\times 10^{-6}$. With the form factors in QCD models, we calculate that ${\cal B}(B_c^-\to X_c^0π^-,X_c^0 K^-)=…
Using the data for 24.5x10^6 psi(2S) produced in e^+e^- annihilations at sqrt{s}=3686 MeV at the CESR-c e^+e^- collider and 8.6x10^6 J/psi produced in the decay psi(2S)->pi^+pi^-J/psi, the branching fractions for psi(2S) and J/psi decays to pairs of pseudoscalar mesons, pi^+pi^-, K^+K^-, and K_S K_L, have been measured using the CLEO-c detector. We obtain branching fractions Br(psi(2S)->pi^+pi^-)=(7.6+-2.5+-0.6)x10^-6, Br(psi(2S)->K^+K^-)=(74.8+-2.3+-3.9)x10^-6, Br(psi(2S)->K_S K_L)=(52.8+-2.5+-3.4)x10^-6, and Br(J/psi->pi^+pi^-)=(1.47+-0.13+-0.13)x10^-4, Br(J/psi->K^+K^-)=(2.86+-0.09+-0.19)x1…
All ALEPH measurements of branching ratios of tau decays involving kaons are summarized including a combination of results obtained with K^0_S and K^0_L detection. The decay dynamics are studied, leading to the determination of contributions from vector K^*(892) and K^{*}(1410), and axial-vector K_1(1270) and K_1(1400) resonances. Agreement with isospin symmetry is observed among the different final states. Under the hypothesis of the conserved vector current, the spectral function for the K\bar{K}πmode is compared with the corresponding cross section for low energy e^+e^- annihilation, yieldi…
The branching ratio of the electromagnetic rare decays $η\toπ^0γγ$ and $η^\prime\to (π^0,η)γγ$ are analysed in terms of scalar and vector meson exchange contributions using the frameworks of the Linear Sigma Model and Vector Meson Dominance, respectively. The measured $η\toπ^0γγ$ process serves as a test of our approach while the non yet measured $η^\prime\to (π^0,η)γγ$ reactions are predicted for the first time. Our prediction for the $η\toπ^0γγ$ decay agrees with recent experimental reported values, thus supporting the validity of our framework. Therefore, our predictions for the $η^\prime\t…
Inclusive branching ratios involving b to tau transitions are measured in approximately four million hadronic Z decays collected by the ALEPH detector at LEP. The fully-inclusive branching ratio b -> tau nu X and the semi-inclusive branching ratio b -> tau nu D*+/- X are measured to be (2.43 +/- 0.20 +/- 0.25)% and (0.88 +/- 0.31 +/- 0.28)%, in agreement with the standard model predictions. Upper limits on the branching fractions b -> tau nu and b -> s nu nubar are set to 8.3 10**-4 and 6.4 10**-4 at the 90% C.L. These results allow a 90% C.L. lower limit of 0.40 (GeV/c**2)**-1 to be set on th…
Electromagnetic radiative penguin decays of the B meson were studied with the BaBar detector at SLAC's PEP-II asymmetric-energy B Factory. Branching fractions and isospin asymmetry of the decay B -> K* gamma, branching fractions of B -> K2*(1430) gamma, and a search for B0 -> phi gamma are presented. The decay rates may be enhanced by contributions from non-standard model processes.
We examine the prospects for measuring the photon-photon branching ratio of a Standard-Model-like Higgs boson ($h$) at the Next Linear $e^+e^-$ Collider when the Higgs boson is produced via $W^+W^-$--fusion: $e^+e^-\toν_e \barν_e h$. In particular, we study the accuracy of such a measurement and the statistical significance of the associated signal as a function of the electromagnetic calorimeter resolution and the Higgs boson mass. We compare results for the $W^+W^-$--fusion production/measurement mode with the results obtained for the $e^+e^-\rightarrow Z^*\rightarrow Z h$ production/measure…
The availability of branching fractions for a large majority of $D_s$ decays permits the prediction of inclusive branching fractions. This is achieved with the help of a modest amount of input from an isospin statistical model applied to non-resonant multibody $D_s$ decays. A systematic uncertainty in these mostly small branching ratios is estimated by comparing predictions of this model with those of a model involving quark-antiquark pair production. The calculated inclusive branching fractions can be compared with data (for example, from a large sample of $D_s^+ D_s^{*-} + D_s^{*+} D_s^-$ ob…
We analyze the quasi-two-body decays $B^+\toπ^+ρ(770,1450)^0 \toπ^+ K^+K^-$ in the perturbative QCD approach. The results in this work do not support that large branching fractions contributed by the resonances $ρ(770,1450)^0$ in the $B^\pm \to π^\pm K^+K^-$ decays. The virtual contribution for $K^+K^-$ from the tail of the resonance $ρ(770)^0$ which has been ignored in the experimental studies is about $1.5$ times of the $ρ(1450)^0 \to K^+K^-$ contribution, with the predicted branching fractions ${\mathcal B}_v=(1.31\pm0.27)\times10^{-7}$ and ${\mathcal B}=(8.96\pm2.61)\times10^{-8}$, respect…
I discuss new results on absolute branching ratios of charm mesons into specific exclusive final states, Cabibbo suppressed decay rates, inclusive decays to $s\bar{s}$ mesons, limits on D^0 anti-D^0 mixing, CP violation and T violation. Preliminary results from CLEO-c now dominate the world average absolute branching fractions. For the most important normalization modes involving D^0 and D^+, the averages are B(D^0 -> K^- pi^+ = (3.87 +/- 0.06)%, and B(D^+ -> K^- pi^+ pi^+)= (9.12 +/- 0.19)%. For the Ds^+ CLEO-c measures B(Ds+ -> K^- K^+ pi^+)=(4.54^{+0.44}_{-0.42} =/- 0.25)%. Using this rate,…
In this paper we address the potential of a 3 TeV centre-of-mass energy Compact Linear Collider (CLIC) to measure the branching fraction of the Higgs boson decay to two photons, BR($H\rightarrowγγ$). Since photons are massless, the Higgs boson coupling to photons is realized through higher order processes involving heavy particles either from the Standard Model or beyond. Any deviation of the measured BR($H\rightarrowγγ$), and consequently of the Higgs coupling $g_{Hγγ}$ from the predictions of the Standard Model, may indicate New Physics. The Higgs decay to two photons is thus an interesting …
Recent measurements of nucleon resonance transition form factors with CLAS at Jefferson Lab are discussed. The new data resolve a long-standing puzzle of the nature of the Roper resonance, and confirm the assertion of the symmetric constituent quark model of the Roper as the first radial excitation of the nucleon. The data on $nπ^+$ production at high $Q^2$ confirm the slow fall off of the $S_{11}(1535)$ transition form factor with $Q^2$, and better constrain the branching ratios $β_{Nπ}=0.50$ and $β_{Nη}=0.45$. Also, new results on the transition amplitudes for the $D_{13}(1520)$ resonance ar…
