Observation of h1(1380) in the J/ψ→

Theoretical description of the J/ψ→η(η′)hWu1, Sakai2, Oset3 2019Phys. Rev. D11190View full textAdd to dashboardCite

“…The comparison of the results for the J=ψ → η 0 h 1 ð1380Þ with the experiment of Ref. [43] requires extra work that we conduct in the next section. Apart from the absolute values of the branching ratios, the ratios of the rates between different decays are very illustrative.…”

“…In Ref. [43] the branching ratio of J=ψ → η 0 h 1 ð1380Þ times the branching ratio Brðh 1 ð1380Þ → K Ãþ K − þ c:c:Þ is measured in the η 0 K þ K − π 0 mode. A branching ratio for this fraction of ð1.51 AE 0.09 AE 0.21Þ × 10 −4 is obtained while a BrðJ=ψ → η 0 h 1 ð1380ÞÞ × Brðh 1 ð1380Þ → K ÃK þ c:c:Þ ¼ ð2.16 AE 0.12 AE 0.29Þ × 10 −4 is observed in the η 0 K 0 S K AE π ∓ mode.…”

“…Very recently the BESIII collaboration has reported the observation of the h 1 ð1380Þ in the J=ψ → η 0 KKπ decay [43]. Selecting η or η 0 in the final state is a good filter for isospin and C-parity such that the extra meson produced is a I G ðJ PC Þ ¼ 0 − ð1 þ− Þ state, assuming s-wave production.…”

Triangle singularities in J/ψ→ηπ0ϕ and π0π0Jing1, Sakai2, Guo3 et al. 2019Phys. Rev. D18210View full textAdd to dashboardCite

“…From the first point of view, because the S-wave π 0 ϕ has J PC ¼ 1 þ− and this decay breaks isospin symmetry, that peak may be related to the isovector resonance claimed in Ref. [13] or the isoscalar h 1 ð1380Þ whose mass is about 1.41 GeV [3,14,15]. 1 From the second point of view, because this is an isospin-breaking process and that peak position about 1.4 GeV is near the threshold of K ÃK , similar to the enhancement of the isospin violation by triangle singularity as seen in the ηð1405=1475Þ → π 0 f 0 ð980Þ [19][20][21][22][23], triangle diagrams involving K ÃK K intermediate states can also lead to a peak and a significant isospin-breaking enhancement here [see also Sec.…”

χc1 decays into a pseudoscalar meson and a vector-vector molecule

“…The same J/ψ decay into three mesons is considered in [10] with J/ψ → V P P , but letting the V P pairs interact to form an axial-vector meson. A mixture of the SU(3) trace V P P and V P P was used and it was shown to correspond to the same structures developed in [3] and [8] and there it was used to describe successfully the BESIII data on the J/ψ → η(η ′ )h 1 (1380) decay [11]. The V P P term was shown to be the one corresponding to the dominant one in [3,8].…”