Speaker
Description
QCD sum rules are widely used non-perturbative tools in hadron physics. Among various formulations, the Laplace and moment sum rules are the most common. However, the Laplace approach suffers from subjectivity in parameter selection, while the moment method cannot extract the coupling constant of the interpolating current. Moreover, the masses obtained from these two methods are often inconsistent. In this work, we propose an improved version of the moment sum rules that addresses these issues. By explicitly incorporating quark-hadron duality --- which introduces an approximation condition $\delta'_n(s_0,Q^2_0) \approx \delta'_{n+1}(s_0,Q^2_0)$ on the OPE side and naturally constrains the parameters as an a posteriori check --- and by further imposing rigorous dependence conditions on unphysical parameters $(Q^2_0,n)$, our framework uniquely determines the physical scale $s_0$ and mass $m_X$ of the lowest-lying resonance without any subjective input. It also enables simultaneous extraction of the coupling $f_X$. Applications to a tetraquark state $ud\overline{d}\overline{s}$ yield results consistent with our previous analyses, thus validating the effectiveness of our proposed scheme.
| 请选择分会 | 强子物理与味物理 |
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