$0^+$ XTZ states from QCD spectral sum rules

TL;DR

This paper uses QCD sum rules to predict the masses and couplings of $0^+$ tetraquark states, refining previous estimates and extending analysis to bottom sector, with results calibrated to known states.

Contribution

It introduces combined sum rule methods to improve mass predictions of $0^+$ tetraquark states and extends analysis to bottom sector, providing more precise theoretical estimates.

Findings

Predicted $T_{cc}^{0^+}$ mass as 3883(3) MeV.

Predicted $T_{ccar{s}ar{u}}^{0^+}$ mass as 3927(6) MeV.

Predicted $T_{ccar{s}ar{s}}^{0^+}$ mass as 3993(11) MeV.

Abstract

We review our results in\,\cite{ANR22} for the masses and couplings of $T_{ccqq'}\, (J^P=0^+)$ states from (inverse) QCD Laplace sum rule (LSR), their ratios ${\cal R}$ and double ratio of sum rules (DRSR) within stability criteria and including Factorized Next-to-Leading Order (FNLO) Perturbative (PT) corrections and Lowest Order (LO) QCD condensates up to $\langle G^3 \rangle$. We show that combining ${\cal R}$ and DRSR can provide more precise results. Calibrated to the observed $X_c(3872)$ and $T^{1^+}_{cc}(3875)$, ${\cal R}$ combined with DRSR lead to a more precise prediction of $M_{T^{0^+}_{cc}}=3883(3)~\rm{MeV}$. In a similar way, calibrated to the new prediction of $T^{0^+}_{cc}$ ${\cal R} \oplus$DRSR lead to the improved mass predictions: $M_{T^{0^+}_{cc\bar{s}\bar{u}}}=3927(6)~\rm{MeV}$ and $M_{T^{0^+}_{cc\bar{s}\bar{s}}}=3993(11)~\rm{MeV}$. We extend our analysis to the bottom sector and compare our results with the ones from different LSR predictions and some other determinations (lattice, quark and potential models,...) in the literature.