Measurements of the branching fractions of $\psi (3686)\to {\bar{\Sigma }}^0\Lambda +c.c.$ and ${\chi }_{cJ(J=0,1,2)}\to \Lambda \bar{\Lambda }$

Abstract

Based on $4.481\times 10^8$ $\psi (3686)$ events collected with the BESIII detector at BEPCII, the branching fraction of the isospin violating decay $\psi (3686)\to {\bar{\Sigma }}^0\Lambda +c.c.$ is measured to be $(1.60\pm 0.31\pm 0.13\pm 0.58)\times 10^{-6}$, where the first uncertainty is statistical, the second is systematic, and the third is the uncertainty arising from interference with the continuum. This result is significantly smaller than the measurement based on CLEO-c data sets. The decays ${\chi }_{cJ}\to \Lambda \bar{\Lambda }$ are measured via $\psi (3686)\to \gamma {\chi }_{cJ}$, and the branching fractions are determined to be $\mathcal{B}\left({\chi }_{c0}\to \Lambda \bar{\Lambda }\right)=(3.64\pm 0.10\pm 0.10\pm 0.07)\times 10^{-4}$, $\mathcal{B}\left({\chi }_{c1}\to \Lambda \bar{\Lambda }\right)=(1.31\pm 0.06\pm 0.06\pm 0.03)\times 10^{-4}$, $\mathcal{B}\left({\chi }_{c2}\to \Lambda \bar{\Lambda }\right)=(1.91\pm 0.08\pm 0.17\pm 0.04)\times 10^{-4}$, where the third uncertainties are systematic due to the $\psi (3686)\to \gamma {\chi }_{cJ}$ branching fractions.

arXiv comment11 pages, 8 figures

References in corpus (24)

• Design and Construction of the BESIII Detector
• The Precision Monte Carlo Event Generator KK For Two-Fermion Final States In e+e- Collisions
• Coherent Exclusive Exponentiation For Precision Monte Carlo Calculations
• Future Physics Programme of BESIII
• Polarization and Entanglement in Baryon-Antibaryon Pair Production in Electron-Positron Annihilation
• Search for hadronic transition ${\chi }_{cJ}\to {\eta }_c{\pi }^{+}{\pi }^{-}$ and observation of ${\chi }_{cJ}\to K\bar{K}\pi \pi \pi$
• Study of ${\chi }_{cJ}$ radiative decays into a vector meson
• Determination of the number of $\psi (3686)$ events at BESIII
• ${\Sigma }^{+}$ and ${\bar{\Sigma }}^{-}$ polarization in the $J/\psi$ and $\psi (3686)$ decays
• Hyperon Form Factors & Diquark Correlations
• Study of $J/\psi$ and $\psi (3686)$ decay to $\Lambda \bar{\Lambda }$ and ${\Sigma }^0{\bar{\Sigma }}^0$ final states
• Colour Octet Contribution in Exclusive P-Wave Charmonium Decay into Octet and Decuplet Baryons
• Study of $\psi$ decays to the ${\Xi }^{-}{\bar{\Xi }}^{+}$ and $\Sigma (1385{)}^{\mp }\bar{\Sigma }(1385{)}^{\pm }$ final states
• Further study of the helicity selection rule evading mechanism in ${\eta }_c$, ${\chi }_{c0}$ and $h_c$ decaying to baryon anti-baryon pairs
• Branching Fraction Measurements of psi(2S) Decay to Baryon-Antibaryon Final States
• Study of J/psi decays to Lambda Lambdabar and Sigma0 Sigma0bar
• Model independent determination of the spin of the ${\Omega }^{-}$ and its polarization alignment in $\psi (3686)\to {\Omega }^{-}{\bar{\Omega }}^{+}$
• Observation of $\psi (3686)\to \Xi (1530{)}^{-}\bar{\Xi }(1530{)}^{+}$ and $\Xi (1530{)}^{-}{\bar{\Xi }}^{+}$
• Measurements of psi(2S) decays to octet baryon-antibaryon pairs
• Determination of the relative phase in ψ' and J/ψ decays into baryon and antibaryon
• Measurements of Baryon Pair Decays of ${\chi }_{cJ}$ Mesons
• First measurements of J/Psi decays into ${\Sigma }^{+}{\bar{\Sigma }}^{-}$ and ${\Xi }^0{\bar{\Xi }}^0$
• Observation of $\psi (3686)\to n\bar{n}$ and improved measurement of $\psi (3686)\to p\bar{p}$
• Measurement of {\boldmath $J/\psi \to \Xi (1530{)}^{-}{\bar{\Xi }}^{+}$} and evidence for the radiative decay {\boldmath $\Xi (1530{)}^{-}\to \gamma {\Xi }^{-}$}

Cited by in corpus (7)

• Production and decay of polarized hyperon-antihyperon pairs
• Symmetry analysis of charmonium two-body decay
• Isospin strikes back
• Observation of the $\psi (3686)$ decays into ${\Sigma }^{+}{\bar{\Sigma }}^{-}\omega$ and ${\Sigma }^{+}{\bar{\Sigma }}^{-}\varphi$
• Isospin violating decays of vector charmonia
• Observation of ${\chi }_{cJ}\to p\bar{p}{K}_S^0{K}^{-}{\pi }^{+}+c.c.$
• Search for the isospin-violating decays ${\mathbf{\chi }}_{\mathbf{cJ}}\to \mathbf{\Lambda }{\bar{\mathbf{\Sigma }}}^0+\mathbf{c}.\mathbf{c}.$ and ${\mathbf{\eta }}_{\mathbf{c}}\to \mathbf{\Lambda }{\bar{\mathbf{\Sigma }}}^0+\mathbf{c}.\mathbf{c}.$