Diffusion Monte Carlo calculation of compact 𝑇𝑐𝑠0 and 𝑇𝑐 ̄ 𝑠0 tetraquarks

Abstract

The LHCb collaboration amplitude analysis of the decays 𝐵+ → 𝐷+𝐷−𝐾+, 𝐵+ → 𝐷−𝐷+ 𝑠 𝜋+, and 𝐵0 → ̄𝐷0𝐷+𝑠 𝜋−suggested the existence of two new resonant 𝐽𝑃 = 0+ states with minimum quark content 𝑢̄𝑑̄𝑠𝑐 and 𝑠̄𝑢̄𝑑𝑐/𝑠̄𝑑̄𝑢𝑐, named 𝑇𝑐𝑠0 and 𝑇𝑐 ̄ 𝑠0, respectively. In this work, we used the diffusion Monte Carlo (DMC) method to compute the masses of those tetraquarks within the framework of the constituent quark model. We describe the systems as compact structures, not as diquark/antidiquark or meson/meson arrangements. In this context, compact means that we used directly the eigenvectors of the spin, color and flavor operators without any splitting and/or (re)combination of smaller units. This allows us to deduce the existence of two distinct bound configurations for each composition, corresponding to ground and excited flavor states. In both cases, the excited flavor states are the ones with masses comparable to the ones observed by LHCb. In addition, our analysis allows us to assign unambiguously an isospin value of 𝐼=1 to the experimentally obtained 𝑇𝑐𝑠0 tetraquark. 1.