Observation of ψ(3686)→ηe+e

BESIII Collaboration

Research output: Contribution to journalArticle

2 Scopus citations


Using a data sample of 448.1×106 ψ(3686) events collected with the BESIII detector at the BEPCII collider, we report the first observation of the electromagnetic Dalitz decay ψ(3686)→ηe+e, with significances of 7.0σ and 6.3σ when reconstructing the η meson via its decay modes η→γπ+π and η→π+πη (η→γγ), respectively. The weighted average branching fraction is determined to be B(ψ(3686)→ηe+e)=(1.90±0.25±0.11)×10−6, where the first uncertainty is statistical and the second systematic.

Original languageEnglish (US)
Pages (from-to)452-458
Number of pages7
JournalPhysics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
StatePublished - Aug 10 2018


  • Charmonium
  • Dalitz decay
  • ee Annihilation

Fingerprint Dive into the research topics of 'Observation of ψ(3686)→η<sup>′</sup>e<sup>+</sup>e<sup>−</sup>'. Together they form a unique fingerprint.

  • Cite this