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arXiv · 1610.09592

$f_2(1810)$ as a triangle singularity

Abstract

We perform calculations showing that a source producing $K^* \bar{K}^*$ in $J = 2$ and $L=0$ gives rise to a triangle singularity at $1810$ MeV with a width of about $200$ MeV from the mechanism $K^* \to \pi K$ and then $K\bar{K}^*$ merging into the $a_1(1260)$ resonance. We suggest that this is the origin of the present $f_2(1810)$ resonance and propose to look at the $\pi a_1(1260)$ mode in several reactions to clarify the issue.

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Ju-Jun Xie, Li-Sheng Geng, Eulogio Oset. 2016-10-30. $f_2(1810)$ as a triangle singularity. https://doi.org/10.1103/physrevd.95.034004

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