Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userMeasurements of branching fractions of leptonic and hadronic Ds+ meson decays and extraction of the Ds+ meson decay constant
129
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We present measurements of absolute branching fractions of hadronic and leptonic Ds+ decays to K- K+ pi+, anti-K0 K+, eta pi+, mu+ nu_mu and tau+ nu_tau and report a search for the leptonic Ds+ to e+ nu_e decays. The results are obtained from a data sample of 913 fb^-1 collected at or near the Y(4S) and Y(5S) resonances with the Belle detector at the KEKB asymmetric-energy e+e- collider. The branching fractions of hadronic decays are measured to be Br(Ds+ -> K- K+ pi+) = (5.06 +- 0.15 +- 0.21)%, Br(Ds+ -> anti-K0 K+) = (2.95 +- 0.11 +- 0.09)%, and Br(Ds+ -> eta pi+) = (1.82 +- 0.14 +- 0.07)%, where the first and second uncertainties are statistical and systematic, respectively. The branching fractions of leptonic decays are measured to be Br(Ds+ -> mu+ nu_mu) = (0.531 +- 0.028 +- 0.020)%, and Br(Ds+ -> tau+ nu_tau) = (5.70 +- 0.21 +0.31-0.30)%, which are combined to determine the Ds+ meson decay constant f_Ds = (255.5 +- 4.2 +- 5.1) MeV. We find no significant signal for Ds+ -> e+ nu_e decays and set an upper limit of Br(Ds+ -> e+ nu_e) < 1.0 (0.83) x 10^-4 at 95% (90%) confidence level.
rate research
Read More
The branching fractions of Ds meson decays serve to normalize many measurements of processes involving charm quarks. Using 586 pb^-1 of e+ e- collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for 13 Ds decays in 16 reconstructed final states with a double tag technique. In particular we make a precise measurement of the branching fraction B(Ds -> K- K+ pi+) = (5.55 +- 0.14 +- 0.13)%, where the uncertainties are statistical and systematic respectively. We find a significantly reduced value of B(Ds -> pi+ pi0 eta) compared to the world average, and our results bring the inclusively and exclusively measured values of B(Ds -> eta X)$ into agreement. We also search for CP-violating asymmetries in Ds decays and measure the cross-section of e+ e- -> Ds* Ds at Ecm = 4.17 GeV.
We have made a precise measurement of the absolute branching fractions of Bs->Ds(*)+ Ds(*)- decays using 121.4 fb-1 of data recorded by the Belle experiment running on the Upsilon(5S) resonance. The results are B(Bs0->Ds+ Ds-) = (0.58 +0.11 -0.09 +-0.13)%, B(Bs0->Ds*+- Ds-+) = (1.8 +-0.2 +-0.4)%, and B(Bs0->Ds*+ Ds*-) = (2.0 +-0.3 +-0.5)%; the sum is B(Bs0->Ds(*)+ Ds(*)- = (4.3 +-0.4 +-1.0)%. Assuming Bs->Ds(*)+ Ds(*)- saturates decays to CP-even final states, the branching fraction constrains the ratio Delta(Gamma_s)/cos(phi_s), where Delta(Gamma_s) is the difference in widths between the two Bs0-Bs0bar mass eigenstates, and phi_s is the CP-violating phase in Bs0-Bs0bar mixing. For phi_s=0 we obtain Delta(Gamma_s)/Gamma_s = 0.090 +-0.009 (stat.) +-0.023 (syst.), where Gamma_s is the mean decay width. We also measure for the first time the longitudinal polarization fraction of Bs->Ds*+ Ds*-; the result is 0.12 +0.30 -0.28 +0.04 -0.05.
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.
The decays Bs0 --> Ds(*)+ Ds(*)- are reconstructed in a data sample corresponding to an integrated luminosity of 6.8 fb-1 collected by the CDF II detector at the Tevatron pbar{p} collider. All decay modes are observed with a significance of more than 10 sigma, and we measure the Bs0 production rate times Bs0 --> Ds(*)+ Ds(*)- branching ratios relative to the normalization mode B0 --> Ds+ D- to be $0.183 pm 0.021 pm 0.017$ for Bs0 --> Ds+ Ds-, $0.424 pm 0.046 pm 0.035$ for Bs0 --> Ds*+- Ds-+, $0.654 pm 0.072 pm 0.065$ for Bs0 --> Ds*+ Ds*-, and $1.261 pm 0.095 pm 0.112$ for the inclusive decay Bs0 --> Ds(*)+ Ds(*)-, where the uncertainties are statistical and systematic. These results are the most precise single measurements to date and provide important constraints for indirect searches for non-standard model physics in Bs0 mixing.
We measure the branching fractions for seven $D_{s}^{+}$ two-body decays to pseudo-scalar mesons, by analyzing data collected at $sqrt{s}=4.178sim4.226$ GeV with the BESIII detector at the BEPCII collider. The branching fractions are determined to be $mathcal{B}(D_s^+to K^+eta^{prime})=(2.68pm0.17pm0.17pm0.08)times10^{-3}$, $mathcal{B}(D_s^+toeta^{prime}pi^+)=(37.8pm0.4pm2.1pm1.2)times10^{-3}$, $mathcal{B}(D_s^+to K^+eta)=(1.62pm0.10pm0.03pm0.05)times10^{-3}$, $mathcal{B}(D_s^+toetapi^+)=(17.41pm0.18pm0.27pm0.54)times10^{-3}$, $mathcal{B}(D_s^+to K^+K_S^0)=(15.02pm0.10pm0.27pm0.47)times10^{-3}$, $mathcal{B}(D_s^+to K_S^0pi^+)=(1.109pm0.034pm0.023pm0.035)times10^{-3}$, $mathcal{B}(D_s^+to K^+pi^0)=(0.748pm0.049pm0.018pm0.023)times10^{-3}$, where the first uncertainties are statistical, the second are systematic, and the third are from external input branching fraction of the normalization mode $D_s^+to K^+K^-pi^+$. Precision of our measurements is significantly improved compared with that of the current world average values.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
