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arXiv · 2609.36925

Spin-2 $QQ\bar Q\bar s$ Tetraquarks in QCD Sum Rules

Abstract

The $J^{P}=2^{+}$ $cc\bar c\bar s$ and $bb\bar b\bar s$ tetraquarks are studied in parallel within the two-point QCD Sum Rules framework using the same symmetric axial-vector$\otimes$axial-vector interpolating current. The current-specific OPE sectors retained through dimension seven within the stated background-field truncation are evaluated with a common symbolic construction, with the bottom channel obtained by the heavy-flavour replacement $c\to b$. The same pole-dominance and OPE-convergence criteria are imposed in both channels. The adopted charm region is $\sqrt{s_0}=5.7\GeV$ with $3.6\le M_B^2\le4.3\GeVsq$, whereas the bottom region is $\sqrt{s_0}=14.3\GeV$ with $9.8\le M_B^2\le10.8\GeVsq$. At representative Borel points, the extracted masses are $5.239\GeV$ and $13.832\GeV$, respectively. After the QCD-input, continuum-threshold, and Borel-window variations are combined, the final results are $m_{cc\bar c\bar s,\,2^+}=5.239\pm0.061\GeV$ and $m_{bb\bar b\bar s,\,2^+}=13.832\pm0.059\GeV$.

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Tarik Akan. 2026-09-29. Spin-2 $QQ\bar Q\bar s$ Tetraquarks in QCD Sum Rules. https://arxiv.org/abs/2609.36925

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