论文标题
QCD中的异国情调的$ 1^{ - +} $混合介子共振
Decays of an exotic $1^{-+}$ hybrid meson resonance in QCD
论文作者
论文摘要
我们介绍了最轻的外来$ j^{pc} = 1^{ - +} $ resonance在lattice qcd中的第一个确定。与SU（3）风味对称性一起工作，在这里，向上，向下和奇怪的夸克质量大约与物理奇怪的夸克质量相匹配，给出了$m_π\ sim 700 $ mev，我们在六个晶格卷上计算有限体积的光谱，这限制了一个散射系统，该散射系统具有八个耦合的通道。在分析上将散射幅度继续进入复杂的能量平面，我们发现了一个对应于狭窄共振的极点奇异性，该谐振表明与开放式伪内尺 - 质量尺度，矢量 - 斜镜和矢量 - 矢量衰减通道相对较弱，但至少在一个Kinemationallyemationicaline Kinemat-cald-cal-pector-pector-pector-pector-pectel-pecter-pecter-pectecte。尝试将耦合耦合到物理轻夸克质量的简单推断表明，通过$b_1π$模式占据较小的$π_1$ resonance衰减，而较小的衰减成$f_1π$，$ρπ$，$η'π$和$ηπ$。可能与实验性$π_1（1564）$候选状态相吻合，该状态在$ηπ$，$η'π$中观察到，我们建议这可能会大大抑制衰减通道。
We present the first determination of the hadronic decays of the lightest exotic $J^{PC}=1^{-+}$ resonance in lattice QCD. Working with SU(3) flavor symmetry, where the up, down and strange quark masses approximately match the physical strange-quark mass giving $m_π\sim 700$ MeV, we compute finite-volume spectra on six lattice volumes which constrain a scattering system featuring eight coupled channels. Analytically continuing the scattering amplitudes into the complex energy plane, we find a pole singularity corresponding to a narrow resonance which shows relatively weak coupling to the open pseudoscalar--pseudoscalar, vector--pseudoscalar and vector--vector decay channels, but large couplings to at least one kinematically-closed axial-vector--pseudoscalar channel. Attempting a simple extrapolation of the couplings to physical light-quark mass suggests a broad $π_1$ resonance decaying dominantly through the $b_1 π$ mode with much smaller decays into $f_1 π$, $ρπ$, $η' π$ and $ηπ$. A large total width is potentially in agreement with the experimental $π_1(1564)$ candidate state, observed in $ηπ$, $η' π$, which we suggest may be heavily suppressed decay channels.
