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Bounds on the CP asymmetry in like sign dileptons from B0 anti-B0 meson decays

The CLEO collaboration Jaffe, D.E. ; Mahapatra, R. ; Masek, G. ; et al.

Phys.Rev.Lett. 86 (2001) 5000-5003, 2001.

Inspire Record 551926 DOI 10.17182/hepdata.47284

We have measured the charge asymmetry in like-sign dilepton yields from B^0 B^0-bar meson decays using the CLEO detector at the Cornell Electron Storage Ring. We find a_ll = [N(l+l+) - N(l-l-)]/[N(l+l+) + N[l-l-)] = +0.013 +/- 0.050 +/- 0.005 . We combine this result with a previous, independent measurement and obtain Re(epsilon_B)/(1+|epsilon_B|^2) = +0.0035 +/- 0.0103 +/- 0.0015 (uncertainties are statistical and systematic, respectively) for the CP impurity parameter, epsilon_B.

1 data table

Table 1

CONST(NAME=EPSILON) is CP impurity parameter.

Measurement of B --> rho l nu decay and |V(ub)|.

The CLEO collaboration Behrens, B.H. ; Ford, William T. ; Gritsan, A. ; et al.

Phys.Rev.D 61 (2000) 052001, 2000.

Inspire Record 500781 DOI 10.17182/hepdata.52337

Using a sample of 3.3 million Upsilon(4S) -> BBbar events collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR), we measure the branching fraction for B -> rho l nu, |V_ub|, and the partial rate (Delta Gamma) in three bins of q^2 = (p_B-p_rho)^2. We find B(B^0 -> rho^- l^+ nu)=(2.69 +- 0.41^+0.35_-0.40 +- 0.50) 10^-4, |V_ub|=(3.23 +- 0.24^+0.23_-0.26 +- 0.58) 10^-3, Delta Gamma (0 < q^2 < 7 GeV^2/c^4) =(7.6 +- 3.0 ^+0.9_-1.2 +- 3.0) 10^-2 ns^-1, Delta Gamma (7 < q^2 < 14 GeV^2/c^4) =(4.8 +- 2.9 ^+0.7_-0.8 +- 0.7) 10^-2 ns^-1, and Delta Gamma (14 < q^2 < 21 GeV^2/c^4) = (7.1 +- 2.1^+0.9_-1.1 +- 0.6)10^-2 ns^-1. The quoted errors are statistical, systematic, and theoretical. The method is sensitive primarily to B -> rho l nu decays with leptons in the energy range above 2.3 GeV. Averaging with the previously published CLEO results, we obtain B(B^0 -> rho^- l^+ nu) = (2.57 +- 0.29^+0.33_-0.46 +- 0.41) 10^-4 and |V_{ub}| = (3.25 +- 0.14 ^+0.21_-0.29 +- 0.55) 10^-3.

1 data table

Table 1

VCB is the V-CKM (Cabibbo-Kobayashi-Maskawa) mixing matrix element. LEPTON+- stands for E+- or MU+-.

Measurements of B ---> D(s)+ X decays

The CLEO collaboration Gibaut, D. ; Kinoshita, K. ; Pomianowski, P. ; et al.

Phys.Rev.D 53 (1996) 4734-4746, 1996.

Inspire Record 401599 DOI 10.17182/hepdata.47241

This paper describes new measurements from CLEO of the inclusive B→Ds+X branching fraction as well as the B+→Ds(*)+D¯(*)0 and B0→Ds(*)+D(*)− branching fractions. The inclusive branching fraction is B(B→Ds+X)=(12.11±0.39±0.88±1.38)% where the first error is statistical, the second is the systematic error, and the third is the error due to the uncertainty in the Ds+→φπ+ branching fraction. The branching fractions for the B→Ds(*)+D¯(*) modes are found to be between 0.9% and 2.4% and are significantly more precise than previous measurements. The sum of the B→Ds(*)+D¯(*) branching fractions is consistent with the results of fits to the inclusive Ds+ momentum spectrum. Factorization is used to arrive at a value for fDs, the Ds+ decay constant. © 1996 The American Physical Society.

1 data table

Table 1

FORMFACTOR(NAME=FP,C=DECAY CONSTANT) is pseudoscalar meson decay constant. Three different methods are used: 1) C=MUNU: D/S+ --> MU+ NUMU, 2) C = ENU: B --> D/S+ D*BAR / B --> D*BAR E+ NU, and 3) C = PI : B --> D/S+ D*BAR / B0 - -> PI+(RHO+) D*BAR-. The F(D/S) is evaluated from B decay assuming the factorization.

Determination of form-factor parameters lambda+ and lambda0 in K(mu3) decay.

Artemov, V.M. ; Volkov, A.D. ; Emelyanenko, G.A. ; et al.

Phys.Atom.Nucl. 60 (1997) 218-223, 1997.

Inspire Record 404831 DOI 10.17182/hepdata.38592

None

1 data table

Table 1

Formfactors F+ and F0 are parameterized as usual F+(0) = F(0)*(1 + CONST*(T/M(PI)**2)).

Measurement of two photon production of the chi(c2)

The CLEO collaboration Shelkov, V. ; Dominick, J. ; Sanghera, S. ; et al.

Phys.Rev.D 50 (1994) 4265-4271, 1994.

Inspire Record 359316 DOI 10.17182/hepdata.52343

The CLEO II detector is used to search for the production of χc2 states in two-photon interactions. We use the signature χc2→γJ/ψ→γl+l− with l=e,μ. Using 1.49 fb−1 of data taken with beam energies near 5.29 GeV, the two-photon width of the χc2 is determined to be Γ(χc2→γγ)=1.08±0.30(stat)±0.26(syst) keV, in agreement with predictions from perturbative QCD.

2 data tables

Table 1

Results below were obtained usign J/psi from-factors in the two photon propogators, and assumes that only transversely polarized photons are significant inthe production of the CHI/C2(1P) state.

Table 2

No description provided.

Two measurements of B0 anti-B0 mixing

The CLEO collaboration Bartelt, John E. ; Csorna, S.E. ; Egyed, Z. ; et al.

Phys.Rev.Lett. 71 (1993) 1680-1684, 1993.

Inspire Record 354226 DOI 10.17182/hepdata.47247

We have measured the B0B¯0 mixing probability, χd, using a sample of 965 000 BB¯ pairs from Υ(4S) decays. Counting dilepton events, we find χd=0.157±0.016±0.018−0.021+0.028. Using tagged B0 events, we find χd=0.149±0.023±0.019±0.010. The first (second) error is statistical (systematic). The third error reflects a ±15% uncertainty in the assumption, made in both cases, that charged and neutral B pairs contribute equally to dilepton events. We also obtain a limit on the CP impurity in the Bd0 system, ‖Re(εB0)‖<0.045 at 90% C.L.

4 data tables

Table 1

No description provided.

Table 2

Mixing parameter from counting dilepton events. CONST(N=MIXING PARAM) = 1/(1 - LAMBDA(C,N)) * (N(2LEPTON+) + N(2LEPTON-))/(N(LEPTON+,LEPTON-) + N(2LEPTON+) + N(2LEPTON-)). LAMBDA(C,N) is the fraction of dilepton events coming from B+B- decays, LAMBDA(C,N) = f(B+)*Br(B+)**2/(f(B+)*Br(B+)**2 + f(B0)*Br(B0)**2), where f(B+),f(B0) are the productiron fractions of the charged and neutral B's at the UPSI(4S), and Br(B+), Br(B0) are the semileptonic brancing fractions.

Table 3

Mixing parameter from tagged B0 events.

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Coherent production of single pions and rho mesons in charged current interactions of neutrinos and anti-neutrinos on neon nuclei at the Fermilab tevatron

The E632 collaboration Willocq, S. ; Aderholz, M. ; Akbari, H. ; et al.

Phys.Rev.D 47 (1993) 2661-2674, 1993.

Inspire Record 334930 DOI 10.17182/hepdata.22725

The coherent production of π and ρ mesons in νμ (ν¯μ)-neon charged-current interactions has been studied using the Fermilab 15-foot bubble chamber filled with a heavy Ne-H2 mix and exposed to the Tevatron quadrupole triplet (anti)neutrino beam. The νμ (ν¯μ) beam had an average energy of 80 GeV (70 GeV). From a sample corresponding to approximately 28 000 charged-current interactions, net signals of (53±9) μ±π∓ coherent events and (19±7) μ±π∓π0 coherent events are extracted. For E>10 GeV, the coherent pion production cross section is determined to be (3.2±0.7)×10−38 cm2 per neon nucleus whereas the coherent ρ production cross section is (2.1±0.8)×10−38 cm2 per neon nucleus. These cross sections and the kinematical characteristics of the coherent events at |t|<0.1 GeV2 are found to be in general agreement with the predictions of a model based on the hadron dominance and, in the pion case, on the partially conserved axial-vector current hypothesis. Also discussed is the coherent production of systems consisting of three pions.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Dimuon Production by Neutrinos in the {Fermilab} 15-ft. Bubble Chamber at the Tevatron

The E632 collaboration Jain, V. ; Harris, F.A. ; Aderholz, M. ; et al.

Phys.Rev.D 41 (1990) 2057, 1990.

Inspire Record 281906 DOI 10.17182/hepdata.22938

The Fermilab 15-ft bubble chamber has been exposed to a quadrupole triplet neutrino beam produced at the Tevatron. The ratio of ν to ν¯ in the beam is approximately 2.5. The mean event energy for ν-induced charged-current events is 150 GeV, and for ν¯-induced charged-current events it is 110 GeV. A total of 64 dimuon candidates (1 μ+μ+, 52 μ−μ+ and μ+μ−, and 11 μ−μ−) is observed in the data sample of approximately 13 300 charged-current events. The number and properties of the μ−μ− and μ+μ+ candidates are consistent with their being produced by background processes, the important sources being π and K decay and punchthrough. The 90%-C.L. upper limit for μ−μ−/μ− for muon momenta above 4 GeV/c is 1.2×10−3, and for momenta above 9 GeV/c this limit is 1.1×10−3. The opposite-sign-dimuon–to–single-muon ratio is (0.62±0.13)% for muon momenta above 4 GeV/c. There are eight neutral strange particles in the opposite-sign sample, leading to a rate per dimuon event of 0.65±0.29. The opposite-sign-dimuon sample is consistent with the hypothesis of charm production and decay.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

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