论文标题
轴向矢量$ d_1 $ hadrons in $ d^\astπ$从qcd散射
Axial-vector $D_1$ hadrons in $D^\astπ$ scattering from QCD
论文作者
论文摘要
我们提出$ i = 1/2 $ $ $ d^\astπ$散射振幅，并确定两个低洼的$ j^p = 1^+$ axial-vector $ d_1 $ d_1 $状态和a $ j^p = 2^+$ tensor $ d_2^\ ast $。计算有限体积的光谱在轻夸克质量上对应于$m_π= 391 $ meV，这是第一次，我们能够约束$ j^p = 1^p = 1^+$ $ $ $ $ $ $ d^\astπ$ amplitudes与$^{2S+1} $ j^p = 2^+$ $ $dπ\ {^1 \！d_2 \} $和$ d^\astπ\ {^3 \！d_2 \} $ amplitudes通过Lüscher的量化条件。分析电线杆的散射幅度，我们找到了一个接近阈值的状态，在$ d^\astπ\ {^3 \！s_1 \} $中产生了广泛的功能。由于$ d_1 $ resonance，$ d^\astπ\ {^3 \！d_1 \} $中发生了狭窄的凸起。在$ j^p = 2^+$耦合到$dπ$和$ d^\astπ$中发现了一个共振。对于最轻的$ D_1 $，发现了相对较低的质量和大型耦合，这表明随着轻夸克质量的减少，该状态将发展为广泛的共鸣。使用相同的轻夸克质量对标量$ d_0^\ ast $的较早计算，可以比较重夸克极限。
We present $I=1/2$ $D^\astπ$ scattering amplitudes from lattice QCD and determine two low-lying $J^P=1^+$ axial-vector $D_1$ states and a $J^P=2^+$ tensor $D_2^\ast$. Computing finite-volume spectra at a light-quark mass corresponding to $m_π=391$ MeV, for the first time, we are able to constrain coupled $J^P=1^+$ $D^\astπ$ amplitudes with $^{2S+1}\ell_J\,=\,^3S_1$ and $^3\!D_1$ as well as coupled $J^P=2^+$ $Dπ\{^1\!D_2\}$ and $D^\astπ\{^3\!D_2\}$ amplitudes via Lüscher's quantization condition. Analyzing the scattering amplitudes for poles we find a near-threshold bound state, producing a broad feature in $D^\astπ\{^3\!S_1\}$. A narrow bump occurs in $D^\astπ\{^3\!D_1\}$ due to a $D_1$ resonance. A single resonance is found in $J^P=2^+$ coupled to $Dπ$ and $D^\astπ$. A relatively low mass and large coupling is found for the lightest $D_1$, suggestive of a state that will evolve into a broad resonance as the light quark mass is reduced. An earlier calculation of the scalar $D_0^\ast$ using the same light-quark mass enables comparisons to the heavy-quark limit.
