Nucleon resonances in πN → η′N and J/ψ → pp̄η′

Abstract

We are aiming to study the J/ψ → ppη ′ decay in an isobar model and the effective Lagrangian approach. After a careful exploration of the contributions of the S11(1535), P11(1710), P13(1900), S11(2090) and P11(2100) resonances, we conclude that either a subthreshold resonance or a broad P -wave state in the near threshold range seems to be indispensable to describe present data of the πN → η ′ N . Furthermore, at least one broad resonance above η ′ N threshold is preferred. With this detailed analysis, we could give the invariant mass spectrum and Dalitz plot of the J/ψ → ppη ′ decay for the purpose of assisting the future detailed partial wave analysis. It is found that the J/ψ → ppη ′ data are useful for disentangling the above or below threshold resonant contribution, though it still further needs the differential cross section data of πN → η ′ N to realize some of the resonant and the non-resonant contribution. Our results are enlightening for the η ′ N production mechanism and the properties of the nucleon resonances with the mass around 2.0 GeV.

Photo- and electro-production of narrow exotic states: from light quarks to charm and up to bottom

“…It is foreseen that once high statistics data will become available in future, partial wave analyses will be feasible for diffractive processes at COMPASS and CLAS [217] and annihilation reactions at BESIII [218] and at PANDA [219]. Other reactions and decays to study them are suggested from the theoretical perspective [33,[220][221][222][223]. A search in the electroproduction of the nonstrange channels is viable when more measurements will become available [200,201,224].…”

Observation ofψ(3686)→pp¯η′and improved measurement ofAblikim1, Ачасов2, Ahmed3 et al. 2019Phys. Rev. D9020View full textAdd to dashboardCite

“…But its natural extension, the three-body decays, ψ → ppP, where P represents a pseudoscalar meson such as π 0 , η, or η 0 , still need more studies since intermediate states contribute significantly here. Specific models based on nucleon and N Ã pole diagrams have been proposed to deal with these problems [3][4][5]. However, recent studies have focused on the final states ppπ 0 and ppη, and not so much on ppη 0 , partially due to the limited experimental measurements.…”

Observation of $ψ(3686) \to p \bar{p} η^{\prime}$ and improved measurement of $J/ψ\to p \bar{p} η^{\prime}$

“…But its natural extension, the three-body decays, ψ → ppP , where P represents a pseudoscalar meson such as π 0 , η, or η ′ , still need more studies since intermediate states contribute significantly here. Specific models based on nucleon and N * pole diagrams have been proposed to deal with these problems [2][3][4]. However, recent studies have focused on the final states ppπ 0 and ppη, and not so much on ppη ′ , partially due to the limited experimental measurements.…”