Measurement of branching fractions for exclusiveBdecays to charmonium final states

Abstract

We report branching fraction measurements for exclusive decays of charged and neutral B mesons into two-body final states containing a charmonium meson. We use a sample of 22.72Ϯ0.36 million BB events collected between October 1999 and October 2000 with the BABAR detector at the PEP-II storage rings at the Stanford Linear Accelerator Center. The charmonium mesons considered here are J/ , (2S), and c1 , and the light meson in the decay is either a K, K*, or 0 .

Averages of $b$-hadron, $c$-hadron, and $τ$-lepton properties as of summer 2014

“…Experiment Ref. Decay modes Published value of Assumed value and year or method R +−/00 = f +− /f 00 of τ (B + )/τ (B 0 ) CLEO, 2001 [9] J/ψ K ( * ) 1.04 ± 0.07 ± 0.04 1.066 ± 0.024 BABAR, 2002 [7] (cc)K ( * ) 1.10 ± 0.06 ± 0.05 1.062 ± 0.029 CLEO, 2002 [10] D * ν 1.058 ± 0.084 ± 0.136 1.074 ± 0.028 Belle, 2003 [11] dilepton events 1.01 ± 0.03 ± 0.09 1.083 ± 0.017 BABAR, 2004 [8] J/ψ K 1.006 ± 0.036 ± 0.031 1.083 ± 0.017 BABAR, 2005 [6] (cc)K ( * ) 1.06 ± 0.02 ± 0.03 1.086 ± 0.017 Average 1.059 ± 0.027 (tot) 1.076 ± 0.004…”

“…The LEP experiments have measured [30,31] and [32,33] 6 from partially reconstructed final states including a lepton, f baryon from protons identified in b events [35], and the production rate of charged b hadrons [36]. Ratios of b-hadron fractions have been measured at CDF using lepton+charm final states [37][38][39] 7 , double semileptonic decays with K * µµ and φµµ final states [40], and fully reconstructed B 0 s → J/ψ φ decays [41]. Measurements of the production of other heavy flavour baryons at the Tevatron are included in the determination of f baryon [42][43][44] 8 using the constraint…”

“…The DELPHI result of Ref [33]. is considered to supersede an older one[34] 7. CDF updated their measurement of f Λ 0 b /f d[37] to account for a measured p T dependence between exclusively reconstructed Λ 0 b and B 0[39].…”

Coulomb effects in the decays $Υ(4S) \rightarrow B\bar B$

“…Note that the mass difference M B 0 − M B + ≈ 0.3 MeV Γ R , and in the first approximation this difference can be neglected. Currently, there are a number of experimental works devoted to the decays of the Υ(4S) meson [1][2][3][4][5][6][7][8][9][10]. The parameter t = πα/v ≈ 0.37, which determines the magnitude of the Coulomb effects, is not small (here v is the velocity of the B meson, α is the fine-structure constant, = c = 1).…”

Study on $η_{c2}(η_{b2})$ electromagnetic decay into double photons

“…[10,11]. Production through B meson decay is an important channel to search for charmonia [12][13][14][15][16][17]. Based on the nonrelativisitc QCD (NRQCD) factorization formalism [18], the inclusive η c2 production in B decay was evaluated and proposed to probe η c2 through this channel [19,20].…”