MEASUREMENT OF THE BRANCHING FRACTIONS FOR INCLUSIVE B[sup -] AND [bar B][sup 0] DECAYS TO FLAVOR-TAGGED D, D[sub S] AND LAMBDA[sub C].


Book Description

The authors report on the inclusive branching fractions of B[sup -] and of [bar B][sup 0] mesons decaying to D[sup 0]X, [bar D][sup 0]X, D[sup +]X, D[sup -]X, D[sub s][sup +]X, D[sub s][sup -]X, [Lambda][sub c][sup +]X, [bar [Lambda]][sub c][sup -]X, based on a sample of 88.9 million B[bar B] events recorded with the BABAR detector at the [Upsilon](4S) resonance. Events are selected by completely reconstructing one B and searching for a reconstructed charmed particle in the rest of the event. The authors measure the number of charmed and of anit-charmed particles per B decay and derive the total charm yield per B[sup -] decay, n[sub c][sup -] = 1.313 [+-] 0.037 [+-] 0.037 [+-] 0.062[sub -0.043][sup +0.063], and per [bar B][sup 0] decay, n[sub c][sup 0] = 1.276 [+-] 0.062 [+-] 0.058[sub -0.046][sup +0.066] where the first uncertainty is statistical, the second is systematic, and the third reflects the charm branching-fraction uncertainties.




MEASUREMENT OF THE BRANCHING FRACTIONS FOR INCLUSIVE B− AND {bar B}° DECAYS TO FLAVOR-TAGGED D, D{sub S} AND LAMBDA{sub C}


Book Description

The authors report on the inclusive branching fractions of B− and of {bar B}° mesons decaying to D°X, {bar D}°X, DX, D−X, D{sub s}+X, D{sub s}−X,?{sub c}+X, {bar {Lambda}}{sub c}−X, based on a sample of 88.9 million B{bar B} events recorded with the BABAR detector at the?(4S) resonance. Events are selected by completely reconstructing one B and searching for a reconstructed charmed particle in the rest of the event. The authors measure the number of charmed and of anit-charmed particles per B decay and derive the total charm yield per B− decay, n{sub c}− = 1.313 ± 0.037 ± 0.037 ± 0.062{sub -0.043}{sup +0.063}, and per {bar B}° decay, n{sub c}° = 1.276 ± 0.062 ± 0.058{sub -0.046}{sup +0.066} where the first uncertainty is statistical, the second is systematic, and the third reflects the charm branching-fraction uncertainties.




FLAVOR-Specific Inclusive B Decays to Charm


Book Description

We have measured the branching fractions for B[yields][bar D]X, B[yields] DX, and B[yields][bar D]X[ell][sup+][nu], where ''B'' is an average over B[sup 0] and B[sup+], ''D'' is a sum over D[sup 0] and D[sup+], and ''[bar D]'' is a sum over[bar D][sup 0] and D[sup -]. From these results and some previously measured branching fractions, we obtain[Beta](b[yields] c[bar c]s)= (21.9[+-] 3.7)%, [Beta](b[yields] sg)




Measurement of the Branching Fractions for the Exclusive Decays of B0 and B+ to Dbar(*)D(*)K.


Book Description

The authors report the observation of 823[+-] 57 B[sup 0] and 970[+-] 65 B[sup+] decays to doubly charmed final states[bar D][sup (*)] D[sup (*)]K, where[bar D][sup (*)] and D[sup (*)] are fully reconstructed and K is either a K[sup[+-]] or a K[sup 0]. They use a sample of 82.3[+-] 0.9 million B[bar B] events collected between 1999 and 2002 with the BABAR detector at the PEP-II storage ring at the Stanford Linear Accelerator Center. The 22 possible B decays to[bar D][sup (*)] D[sup (*)]K are reconstructed exclusively and the corresponding branching fractions or limits are determined. The branching fractions of the B[sup 0] and of the B[sup+] to[bar D][sup (*)] D[sup (*)]K are found to be[Beta](B[sup 0][yields][bar D][sup (*)]D[sup (*)]K)= (4.3[+-] 0.3(stat)[+-] 0.6(sys))%, [Beta](B[sup+][yields][bar D][sup (*)] D[sup (*)]K)= (3.5[+-] 0.3(stat)[+-] 0.5(syst))%.




Measurement of the Branching Fraction for B- --] D0 K*-


Book Description

The authors present a measurement of the branching fraction for the decay B[sup -] [yields] D[sup 0]K*[sup -] using a sample of approximately 86 million B[bar B] pairs collected by the BABAR detector from e[sup +]e[sup -] collisions near the [Upsilon](4S) resonance. The D[sup 0] is detected through its decays to K[sup -] [pi][sup +], K[sup -][pi][sup +][pi][sup 0] and K[sup -] [pi][sup +][pi][sup -][pi][sup +], and the K*[sup -] through its decay to K[sub S][sup 0] [pi][sup -]. They measure the branching fraction to be [Beta](B[sup -] [yields] D[sup 0]K*[sup -]) = (6.3 [+-] 0.7(stat.) [+-] 0.5(syst.)) x 10[sup -4].







Branching Fraction for B+ -] Pi0 L+ Nu, Measured in Upsilon (4S) -] BBbar Events Tagged by B- -] D0 L- Nubar (X) Decays


Book Description

We report a preliminary branching fraction of (1.80 {+-} 0.37{sub stat.} {+-} 0.23{sub syst.}) x 10{sup -4} for the charmless exclusive semileptonic B{sup +} {yields} {pi}{sup 0}{ell}{sup +}{nu} decay, where {ell} can be either a muon or an electron. This result is based on data corresponding to an integrated luminosity of 81 fb{sup -1} collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses B{bar B} events that are tagged by a B meson reconstructed in the semileptonic B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}(X) decays, where X can be either a {gamma} or a {pi}{sup 0} from a D* decay.




MEASUREMENT OF THE BRANCHING FRACTIONS FOR THE DECAYS B[sup 0]--]D*[sup -] P[bar P][pi][sup +], B[sup 0]--]D[sup -]p[bar P][pi][sup +], B0--]D*[sup 0] P[bar P] AND B[sup 0]--]D[sup 0] P[bar P].


Book Description

The B[sup 0] meson decay modes B[sup 0] --> D*[sup -]p[bar p][pi][sup +], D[sup -]p[bar p][sup +], [bar D]*[sup 0]p[bar p], and B[sup 0] --> [bar D][sup 0]p[bar p] are studied in a sample of 124 x 10[sup 6] B[bar B] pairs collected with the BABAR detector at the PEP-II collider. The decay of B[sup 0] --> D[sup -]p[bar p][pi][sup +] is observed for the first time, with a measured branching fraction B(B[sup 0] --> D[sup -]p[bar p][pi][sup +]) = (3.80 [+-] 0.35 [+-] 0.46) x 10[sup -4]. The following branching fractions are also determined: B(B[sup 0] --> D*[sup -]p[bar p][pi][sup +]) = (5.61 [+-] 0.59 [+-] 0.73) x 10[sup -4], B(B[sup 0] --> [bar D]*[sup 0] p[bar p]) = (0.67 [+-] 0.21 [+-] 0.09) x 10[sup -4], and B(B[sup 0] --> [bar D][sup 0]p[bar p]) = (1.24 [+-] 0.14 [+-] 0.12) x 10[sup -4]. In each decay mode the invariant mass spectra of the charmed mesons and the baryons are compared with a pure phase-space hypothesis in order to gain insight into the B meson decay dynamics. In particular, the Dalitz plots of [bar D]*[sup 0]p versus [bar D]*[sup 0][bar p] for B[sup 0] --> [bar D]*[sup 0]p[bar p] and of [bar D][sup 0]p versus [bar D][sup 0][bar p] for B[sup 0] --> [bar D][sup 0]p[bar p] are presented. All results are preliminary.







Measurement of the Branching Fraction for the Decay B[sup 0]--]D[sup*+]D[sup*-].


Book Description

Decays of the type B[yields] D[sup (*)][bar D](*) can be used to provide a measurement of the parameter sin2[beta] of the Unitarity Triangle that is complementary to the measurement derived from the mode B[sup 0][yields]/K[sub S][sup 0]. In this document we report a measurement of the branching fraction for the decay B[sup 0][yields] D*[sup+]D*[sup -] with the BABAR detector. With data corresponding to an integrated luminosity of 20.7 fb[sup -1] collected at the[Upsilon](4S) resonance during 1999-2000, we have reconstructed 38 candidate signal events in the mode B[sup 0][yields] D*[sup+]D*[sup -] with an estimated background of 6.2[+-] 0.5 events. From these events, we determine the branching fraction to be[Beta](B[sup 0][yields] D*[sup+]D*[sup -])= (8.0[+-] 1.6(stat)[+-] 1.2(syst)) x 10[sup -4] (preliminary). The measured fraction of the component with odd CP parity is 0.27[+-] 0.17(stat)[+-] 0.02(syst).