arXiv subjects
Publications and source records attributed to Breno Agatão.
In this talk, I will discuss the properties of several exotic states with charm and/or strangeness. These states can be interpreted either as being generated from two- or three-hadron dynamics. In particular, I will focus on $D_1(2420)$ and some predictions of three-body states obtained from $n\bar
We present a model calculation to reproduce the differential mass distribution for the $D^*π$ system in the reactions $B^- \to D^{*+} π^- π^-$ and $B^{+}\to D_s^+D^{*-}π^{+}$ analyzed by the LHCb Collaboration, which shows a dominant signal for $D_1(2420)$. %\textbf{We} (The idea is to) We consider a model based on coupled channel meson-meson interactions that can describe the properties of $D_1(2420)$ in terms of the underlying dynamics, use it to determine the invariant mass distribution of the $D^*π$ system, and compare the results with the experimental data. We also determine the $D^*π$ scattering length, for which different values are available from different sources, leading to a controversy. To our knowledge, this is the first attempt to reproduce the mentioned data using model calculations. Our formalism relies on the hadronization of different mesons through a weak decay, allowing for the final-state (strong) interactions among the relevant constituents. We benefit from our previous work when obtaining the amplitudes corresponding to the strong interactions. We hope that our findings can be useful in further investigations of the properties of $D_1(2420)$.
We study the interaction of the $n \bar {D}_{s1}(2460)$ and $n \bar {D}_{s1}(2536)$ systems from the perspective that the $D_{s1}(2460)$ and $D_{s1}(2536)$ states are molecular states of $K D^*$ and $K^*D$, respectively. We use an improved version of the fixed center approximation to the Faddeev equations which fulfills exact elastic unitarity at the threshold of the systems. We predict the existence of resonant states below threshold and also determine the scattering length, effective range and correlation functions of these systems, showing that the results contain important information to test the assumed molecular nature of the two $D_{s1}$ states.
We present a detailed study of the partial decay widths of a spin-parity resonance $J^P=3/2^-$ $N^*$ with a mass of $\simeq$ 2070 MeV obtained from the coupled channel s wave vector-baryon $ρN$, $ωN$, $ϕN$, $K^*Λ$ and $K^*Σ$ dynamics. This state, which couples strongly to the $K^*Σ$ channel, corresponds to a nucleon with a hidden strange quark content, in analogy to the $P_c$ states discovered by the LHCb collaboration, and we denote it as $P_s(2080)$. A state with such a nature can decay to vector-baryon, pseudoscalar-baryon, and pseudoscalar-baryon resonance channels, involving triangular loops in the latter two cases. As we will show, the partial decay widths to pseudoscalar-baryon resonance channels, like $πN^*(1535)$, $πN^*(1650)$, $KΛ(1405)$, are comparable to those related to ground state baryons in the final state, like $πN$, $ηN$, $KΛ$. In this way, reactions involving such lighter baryon resonances in the final state can be used as an alternative source of information on the properties of a $N^*$ with hidden strangeness.