11 pages, 8 figures, Proceedings of the 34th International Conference on High-Energy Physics (ICHEP 08), Philadelphia, USA, July 29th - August 5th, 2008
I review some recent results on hadronic decays of charmed mesons. These decays illuminate a wide range of physics, including the absolute normalizations of b and c decays, the understanding of D^0 mixing, the coupling of heavy mesons to hadronic decay products, and light hadron spectroscopy.
Identification of charmonium states at hadron colliders has mostly been limited to leptonic decays of the J/ψ. In this paper we present and algorithm to identify hadronic decays of charmonium states (J/ψ, ψ(2S), χ_{c0,1,2}) which make up the large majority of all decays. The algorithm is able to identify hadronic $J/ψ$ decays with an efficiency of 36\% while suppressing a background of quark and gluon jets by a factor 100.
Hadronic $B$ decays without a charm quark constitute a powerful probe to search for physics beyond the standard model as well as to provide constraints on $CP$ violation parameters. We report final measurements from Belle of the branching fractions and $CP$ asymmetries for the decays $B^{0} \rightarrow π^{0} π^{0}$ and $B^{\pm} \rightarrow K^{+} K^{-} π^{\pm}$. The $B^{0} \rightarrow π^{0} π^{0}$ measurements enable us to improve constraints on the angle $ϕ_{2}$ of the CKM unitarity triangle. For $B^{\pm} \rightarrow K^{+} K^{-} π^{\pm}$ we measure $CP$ asymmetry as a function of the invariant…
We present preliminary results of several searches for rare charmless hadronic decays of the B meson using data collected by the BABAR detector at the Stanford Linear Accelerator Center's PEP-II storage ring. We search for the decays h^+h^-, h^+h^-h^+, h^+h^-pi^0, X^0h^+, and X^0 K_S^0, where h = pi or K, and X^0 = eta^prime or omega. In a sample of 8.8 million B-anti-B decays we measure the branching fractions: BF(B^0 --> pi^+pi^-) = (9.3^{+2.6}_{-2.3}^{+1.2}_{-1.4}) x 10^{-6}, BF(B^0 --> K^+pi^-) = (12.5^{+3.0}_{-2.6}^{+1.3}_{-1.7}) x 10^{-6}, BF(B^0 --> rho^-pi^+) = (49 +/- 13^{+6}_{-5}) x …
Study of B meson decays to three-body charmless hadronic final states
本文报道无粲B介子衰变到三体KPiPi、KKPi和KKK末态的研究结果。测量了B衰变到K+0 Pi +Pi-,K+K+K-,K 0 K +K-,KsKsK+和KsKsKs终态的分支分数。首次观察到衰变B_0 => K_0 K +K ~-,B ~+=>KsKsK ~+和B_0 =>KsKsKs。我们还报道了B+=>K+K-Pi+衰变的证据。对于三体最终状态K 0 K +K-、KsKsPi+、K+K+Pi-和K-Pi+Pi+,报告了90%置信水平上限。最后讨论了用三体B 0 =>KsK+K衰变研究CP破坏的可能性。这些结果是由KEKB非对称能量e+e对撞机上的Belle探测器在Y(4S)共振下采集的78 fb^-1数据样本得到的。
Charmless hadronic $B$ decays are a good testing ground for the Standard Model (SM) of Particle Physics. The dominant amplitudes are CKM suppressed tree diagrams and/or $ b\to s$ or $b\to d$ loop ("penguin") diagrams. Non-SM particle could appear in the loop, and hence these decays are sensitive to search for New Physics (NP). Some of the recent measurements of two-body charmless hadronic $B$ decays from Belle and their prospects at Belle II are discussed.
The BESIII experiment has collected the $e^+e^-$ collision data samples corresponding to integrated luminosities of 2.93 $\mathrm{fb}^{-1}$, $3.19$ $\mathrm{fb}^{-1}$, 3.13 $\mathrm{fb}^{-1}$ and 567 $\mathrm{pb}^{-1}$ at center-of-mass energies of 3.773 GeV, 4.178 GeV, 4.189-4.226 GeV and 4.599 GeV, respectively. We report the measurements of strong-phase parameters based on the decays $D^0\to K^0_{S/L}π^+π^-$, $D^0\to K^0_{S/L}K^+K^-$, $D^0\to K^-π^+π^+π^-$ and $D^0\to K^-π^+π^0$, which are important input for binned model-independent measurement of the CKM angle $γ/ϕ_3$. In addition, we rep…
In this work, we investigate the open-charm decay process $ψ\toΛ_c\barΛ_c$ via the hadronic loop mechanism for vector charmonia above $Λ_c\barΛ_c$ threshold. The branching ratios of these vector charmonium states to $Λ_c\barΛ_c$ are estimated. The charmonium explanation of the $Y(4630)$ observed in $e^+e^- \to Λ_c\barΛ_c$ is tested. Furthermore, for the predicted higher vector charmonia above 4.7 GeV, the branching ratios $\mathcal{B}[ψ(nS)\toΛ_c\barΛ_c]$ with $n=7,8,9$ are found to be of the order of magnitude of $10^{-4}-10^{-3}$ while $\mathcal{B}[ψ(mD)\toΛ_c\barΛ_c]$ with $m=6,7,8$ are of …
Charm penguin diagrams are known to be the main contribution to charmless B decay process with strangeness variation equal to minus one, which is the case of $B^\pm \to K^\pm K^+ K^-$ decay. The large phase space available in this and other B three-body decays allows non trivial final state interactions with all sort of rescattering processes and also access high momentum transfers in the central region of the Dalitz plane. In this work we investigate the charm Penguin contribution to $B^\pm \to K^\pm K^+ K^-$, described by a hadronic triangle loop in nonperturbative regions of the phase space…