Related papers: $f_2(1810)$ as a triangle singularity
We have studied the production and decay of the $f_1(1285)$ into $\pi a_0(980)$ and $K^* \bar K$ as a function of the mass of the resonance and find a shoulder around 1400 MeV, tied to a triangle singularity, for the $\pi a_0(980)$ mode,…
We show that the $\tau^-$ decay into $f_1(1285)\pi^-\nu_\tau $ is dominated by a triangle loop mechanism with $K^*$, $\bar K^*$ and $K$ (or $\bar K$) as internal lines, which manifests a strong enhancement reminiscent of a nearby…
We study the $J/\psi \rightarrow K^+ K^- f_0(980)(a_0(980))$ reaction and find that the mechanism to produce this decay develops a triangle singularity around $M_{\rm inv}(K^- f_0/K^- a_0) \approx 1515$~MeV. The differential width $d\Gamma…
The role of triangle mechanism in the decay process $J/\psi \to K^- K^+ a_1(1260)$ is probed. In this mechanism, a close-up resonance with mass $1823$ MeV and width $122$ MeV decays into $K^* \phi, K^* \to K \pi$ and then $K^* \bar{K}$…
The possible role of the triangle mechanism in the $B^-$ decay into $D^{*0}\pi^-\pi^0\eta$ and $D^{*0}\pi^-\pi^+\pi^-$ is investigated. In this process, the triangle singularity appears from the decay of $B^-$ into $D^{*0}K^-K^{*0}$…
We study the $\bar K p \to Y K\bar K \pi$ reactions with $\bar K = \bar K^0, K^-$ and $Y=\Sigma^0, \Sigma^+, \Lambda$, in the region of $K\bar K \pi$ invariant masses of $1200-1550$ MeV. The strong coupling of the $f_1(1285)$ resonance to…
We study the decay mode of the $a_1(1260)$ into a $\pi^+$ in p-wave and the $f_0(980)$ that decays into $\pi^+ \pi^-$ in s-wave. The mechanisms proceeds via a triangular mechanism where the $a_1(1260)$ decays into $K^* \bar K$, the $K^*$…
We show the effects of a triangle singularity mechanism for the $\gamma p \to K^+\Lambda(1405)$ reaction. The mechanism has a $N^*$ resonance around 2030 MeV, which decays into $K^* \Sigma$. The $K^*$ decays to $K^+ \pi$, and the $\pi…
The COMPASS experiment recently discovered a new isovector resonance-like signal with axial-vector quantum numbers, the $a_1(1420)$, decaying to $f_0(980)\pi$. With a mass too close to and a width smaller than the axial-vector ground state…
We study the $J/\psi \to \phi K \bar K$ decay, looking for differences in the production rates of $K^+ K^-$ or $K^0 \bar K^0$ in the region of 1700-1800 MeV, where two resonances appear dynamically generated from the vector-vector…
We perform calculations for the $\bar B_s^0 \to J/\psi \pi^0 f_0(980)$ and $\bar B_s^0 \to J/\psi \pi^0 a_0(980)$ reactions, showing that the first one is isospin-suppressed while the second one is isospin-allowed. The reaction proceeds via…
We have investigated the cross section for the $\pi^-p\rightarrow K^0\pi\Sigma$ and $pp\rightarrow pK^+\pi\Sigma$ reactions paying attention to a mechanism that develops a triangle singularity. The triangle diagram is realized by the decay…
The resonance-like signal with axial-vector quantum numbers $J^{PC}=1^{++}$ at a mass of $1420\,$MeV and a width of $140\,$MeV, recently observed by the COMPASS and VES experiments in the $f_0(980)\pi$ final state and tentatively called…
We investigate the three-body system of $\pi \bar{K} K^*$ by using the fixed-center approximation to the Faddeev equation, taking the interaction between $\pi$ and $\bar{K}$, $\pi$ and $K^*$, and $\bar{K}$ and $K^*$ from the chiral unitary…
We study the process $D^0 \to \pi^+ \pi^- f_0(980),\ f_0 \to \pi^+ \pi^-$ by introducing the triangle mechanism, in which $f_0(980)$ is considered to be dynamically generated from the meson-meson interaction. For the total contribution of…
A study of three-pseudoscalar $\pi K \bar{K}$ and $\pi \pi \eta$ coupled system is made by solving the Faddeev equations within an approach based on unitary chiral dynamics. A resonance with total isospin one and spin-parity $J^\pi = 0^-$…
We have investigated the process $J/\psi \to {\bar{K}}^0K^+\rho^-$ by taking into account the $S$-wave ${K^*\bar{K}^*}$, $\rho \omega$, and $\rho \phi$ final-state interactions, where the scalar meson $a_0(1710)$ is generated. In addition,…
The $K K\bar K$ system is investigated with a coupled channel approach based on solving the Faddeev equations considering the $KK\bar K$, $K\pi\pi$ and $K\pi\eta$ channels and using as input two-body $t$-matrices that generate dynamically…
We investigate the process $\eta_c \to {\bar{K}}^0K^+\pi^-$ by taking into account the $S$-wave ${K^*\bar{K}^*}$ and $\rho\omega$ interactions within the unitary coupled-channel approach, where the scalar meson $a_0(1710)$ is dynamically…
We perform a Faddeev calculation for the three mesons system, $\phi K \bar{K}$, taking the interaction between two pseudoscalar mesons and between a vector and a pseudoscalar meson from the chiral unitary approach. We obtain a neat…