Çetin, Serkant Ali2020-12-152020-12-152016-03-032470-00292470-0010https://hdl.handle.net/11411/2854https://doi.org/10.1103/PhysRevD.93.052005We search for a light Higgs boson A(0) in the fully reconstructed decay chain of J/psi -> gamma A(0), A(0)-> mu(+)mu(-) using (225.0 +/- 2.8) x 10(6) J/psi events collected by the BESIII experiment. The A(0) is a hypothetical CP-odd light Higgs boson predicted by many extensions of the Standard Model including two spin-0 doublets plus an extra singlet. We find no evidence for A(0) production and set 90% confidence-level upper limits on the product branching fraction B(J/psi -> gamma A(0)) x B(A(0)-> mu(+)mu(-)) in the range of (2.8-495.3) x 10(-8) for 0.212 <= mA(0) <= 3.0 GeV/c(2). The new limits are five times below our previous results, and the nature of the A(0) is constrained to be mostly singlet.eninfo:eu-repo/semantics/openAccessLEPTONIC DECAYSSTANDARD MODELQUARKONIUMEXTENSIONFACTORIESEVENTSGAMMAArticle2-s2.0-8496115716010.1103/PhysRevD.93.052005Q1WOS:000371413800003