Observation of <i>ψ</i>(3686) → <i>e</i><SUP>+</SUP><i>e</i><SUP>-</SUP><i>χ<sub>cJ</sub></i> and <i>χ<sub>cJ</sub></i> → <i>e</i><SUP>+</SUP><i>e</i><SUP>-</SUP><i>J</i>/<i>ψ</i>
PHYSICAL REVIEW LETTERS, vol.118, no.22, 2017 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 118 Issue: 22
- Publication Date: 2017
- Doi Number: 10.1103/physrevlett.118.221802
- Journal Name: PHYSICAL REVIEW LETTERS
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Open Archive Collection: AVESIS Open Access Collection
- Bursa Uludag University Affiliated: No
Abstract
Using 4.479 x 10(8) psi(3686) events collected with the BESIII detector, we search for the decays psi(3686) -> e(+)e(-)chi(cJ) and chi(cJ) -> e(+)e(-)J/psi, where J = 0, 1, 2. The decays psi(3686) -> e(+)e(-)chi(cJ) and chi(cJ) -> e(+)e(-)J/psi are observed for the first time. The measured branching fractions are B(psi(3686) -> e(+)e(-)chi(cJ)) = (11.7 +/- 2.5 +/- 1.0) x 10(-4), (8.6 +/- 0.3 +/- 0.6) x 10(-4), (6.9 +/- 0.5 +/- 0.6) x 10(-4) for J = 0, 1, 2, and B(chi(cJ) -> e(+)e(-)J/psi) = (1.51 +/- 0.30 +/- 0.13)x10(-4), (3.73 +/- 0.09 +/- 0.25)x10(-3), (2.48 +/- 0.08 +/- 0.16)x10(-3) for J = 0, 1, 2, respectively. The ratios of the branching fractions B(psi(3686) -> e(+)e(-)chi(cJ))/B(psi(3686) -> gamma chi(cJ)) and B(chi(cJ) -> e(+)e(-)J/psi)/B(chi(cJ) -> gamma J/psi) are also reported. Also, the alpha values of helicity angular distributions of the e(+)e(-) pair are determined for psi(3686) -> e(+)e(-)chi(c1,2) and chi(c1,2) -> e(+)e(-)J/psi.