31 de outubro de 2023 | Publicações
G. Ramalho, K. Tsushima
Physical Review D
24/10/2023
Abstract
We study the role of the meson cloud on the electromagnetic transitions from decuplet (B′) to octet (B) baryons in terms of the squared four-momentum transfer q2. In the quark model framework, the meson cloud dressing of the quark cores gives important contributions to the γ∗N→Δ(1232) transition form factors. In the present work, we estimate the meson cloud contributions of all decuplet to octet baryon transitions (γ∗B→B′ or B′→γ∗B). Models that combine valence quark effects with pion and kaon cloud dressing provide a fair description of the radiative decays of decuplet to octet baryons, namely the Σ0(1385)→γΛ(1116) and Σ+(1385)→γΣ+(1193) decays. Previous studies indicated the relevance of the pion cloud effects on the B′→γ∗B transition but also suggested that the kaon cloud contributions may be important in the timelike region. We combine then the contributions of the bare core, estimated by a covariant quark model, with q2-dependent contributions of pion and kaon clouds. We use the framework to calculate the Dalitz decay rates and the Dalitz decay widths of decuplet baryons in octet baryons with dielectrons (B′→e+e−B) or dimuons (B′→μ+μ−B). We conclude, based on the magnitude of our results, that most estimates of the B′→e+e−B Dalitz decay widths may be tested at HADES and PANDA (GSI) in the near future. We discuss also the possibility of measuring the Δ(1232)→μ+μ−N and Σ0(1385)→μ+μ−Λ(1116) decay widths in some facilities, based on the estimated branching ratios.