Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userMeasurement of {boldmath $J/psitoXi(1530)^{-}barXi^{+}$} and evidence for the radiative decay {boldmath $Xi(1530)^{-}togammaXi^-$}
98
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The SU(3)-flavor violating decay $J/psitoXi(1530)^{-}barXi^{+}+c.c.$ is studied using $(1310.6pm7.0)times 10^{6} ~J/psi$ events collected with the BESIII detector at BEPCII and the branching fraction is measured to be ${cal{B}}(J/psitoXi(1530)^{-}barXi^{+}+c.c.)=(3.17pm0.02_{rm stat.}pm0.08_{rm syst.})times10^{-4}$. This is consistent with previous measurements with an improved precision. The angular parameter for this decay is measured for the first time and is found to be $alpha=-0.21pm0.04_{rm stat.}pm0.06_{rm syst.}$. In addition, we report evidence for the radiative decay $Xi(1530)^{-}togammaXi^- $ with a significance of 3.9$sigma$, including the systematic uncertainties. The 90% confidence level upper limit on the branching fraction is determined to be $mathcal{B}(Xi(1530)^{-}togammaXi^- )leq3.7$%.
rate research
Read More
Using 448.1 $times$ $10^{6}$ $psi(3686)$ events collected with the BESIII detector at BEPCII, we employ a single-baryon tagging technique to make the first observation of $psi(3686)rightarrowXi(1530)^{-}barXi(1530)^{+}$ and $Xi(1530)^{-}barXi^{+}$ decays with a statistical significance of more than 10$sigma$ and 5.0$sigma$, respectively. The branching fractions are measured to be $cal{B}$$[psi(3686)rightarrowXi(1530)^{-}barXi(1530)^{+}] $ = (11.45 $pm$ 0.40 $pm$ 0.59) $times$ $10^{-5}$ and $cal{B}$$[psi(3686)rightarrowXi(1530)^{-}barXi^{+}]$ = (0.70 $pm$ 0.11 $pm$ 0.04) $times$ $10^{-5}$. The angular distribution parameter for $psi(3686)rightarrowXi(1530)^{-}barXi(1530)^{+}$ is determined to be $alpha$ = 0.40 $pm$ 0.24 $pm$ 0.06, which agrees with the theoretical predictions within 1$sigma$. The first uncertainties are statistical, and the second systematic.
Using $(448.1pm2.9)times 10^{6}$ $psi(3686)$ events collected with the BESIII detector and a single-baryon tagging technique, we present the first observation of the decays $psi(3686)toXi(1530)^{0}bar{Xi}(1530)^{0}$ and $Xi(1530)^{0}bar{Xi}^0$. The branching fractions are measured to be ${cal{B}}(psi(3686)toXi(1530)^{0}bar{Xi}(1530)^{0}) = (6.77pm0.14pm0.39)times10^{-5}$ and ${cal{B}}(psi(3686)toXi(1530)^{0}bar{Xi}^{0}) = (0.53pm0.04pm0.03)times10^{-5}$. Here, the first and second uncertainties are statistical and systematic, respectively. In addition, the parameter associated with the angular distribution for the decay $psi(3686)toXi(1530)^{0}bar{Xi}(1530)^0$ is determined to be $alpha = 0.32pm0.19pm0.07$, in agreement with theoretical predictions within one standard deviation.
We perform a helicity amplitude analysis for the processes of $e^+e^-$$rightarrow$$J/psi,psi(2S)rightarrowXi(1530)barXi(1530)rightarrowpipiXibarXirightarrowLambdabarLambda4pirightarrow pbar{p}6pi$. The joint angular distribution for these processes are obtained, which allows a proper estimation of the detection efficiency using helicity amplitude information. In addition, the sensitivities of measurement of hyperon asymmetry decay parameters for these processes are discussed.
We report the first measurements of absolute branching fractions for the $W$-exchange-only processes $Lambda^+_ctoXi^0K^+$ and $Lambda^+_ctoXi(1530)^0K^+$ with the double-tag technique, by analyzing an $e^{+}e^{-}$ collision data sample, that corresponds to an integrated luminosity of 567 pb$^{-1}$ collected at a center-of-mass energy of 4.6 GeV by the BESIII detector. The branching fractions are measured to be $mathcal{B}(Lambda^+_ctoXi^0K^+)=(5.90pm0.86pm0.39)times10^{-3}$ and $mathcal{B}(Lambda^+_ctoXi(1530)^0K^+)=(5.02pm0.99pm0.31)times10^{-3}$, where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.
The half-life of tsups{37}K has been measured to be $1.23651(94)~mathrm{s}$, a value nearly an order of magnitude more precise than the best previously reported. The $beta^+$ decay of tsups{37}K occurs mainly via a superallowed branch to the ground-state of its $T=1/2$ mirror, tsups{37}Ar. This transition has been used recently, together with similar transitions from four other nuclei, as an alternative test of CVC and method for determining $V_{ud}$, but the precision of its $ft$ value was limited by the relatively large half-life uncertainty. Our result corrects that situation. Another motivation for improving the $ft$ value was to determine the standard-model prediction for the $beta$-decay correlation parameters, which will be compared to those currently being measured by the trinat{} collaboration at triumf. The new $ft$ value, $4605(8)~mathrm{s}$, is now limited in precision by the $97.99(14)%$ ground-state branching ratio.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
