论文标题
过渡形式的框架依赖性在光线动力学中
Frame dependence of transition form factors in light-front dynamics
论文作者
论文摘要
我们研究了轻型汉密尔顿方法中载体和伪夸克的辐射转变，并研究使用不同电流成分和不同参考帧的效果。在用截短的Fock空间的实际计算中，过渡形式可能会获得当前的组件依赖性和框架依赖性，并且这种依赖性可以作为洛伦兹对称违规的量度。我们建议使用$ m_j = 0 $的横向电流，因为该过程采用了轻率波函数的主要自旋组件，并且在实际计算中更强大。我们计算矢量和伪夸尔克尼亚的过渡形式，并研究框架依赖性，该框架的依赖性是用从价Fock扇区计算出的光前波形的。我们建议使用具有最小纵向动量转移的框架进行价值扇区的计算，即带有太空区域的Drell-Yan框架，以及时间层状区域的特定纵向框架。在$ q^2 = 0 $，这两个帧给出相同的结果。
We study the radiative transitions between vector and pseudoscalar quarkonia in the light-front Hamiltonian approach, and investigate the effects of using different current component and different reference frames. In practical calculations with truncated Fock spaces, transition form factors may acquire current component dependence and frame dependence, and such dependences could serve as a measure for the Lorentz symmetry violation. We suggest using the transverse current with $m_j=0$ state of the vector meson, since this procedure employs the dominant spin components of the light-front wavefunctions and is more robust in practical calculations. We calculate the transition form factor between vector and pseudoscalar quarkonia and investigate the frame dependence with light-front wavefunctions calculated from the valence Fock sector. We suggest using frames with minimal longitudinal momentum transfer for calculations in the valence Fock sector, namely the Drell-Yan frame for the space-like region and a specific longitudinal frame for the timelike region; at $q^2=0$ these two frames give the same result.
