By combining the Large Sky Area Multi-object Fiber Spectroscopic Telescope and Gaia data, we investigate the vertical phase mixing across the Galactic disk. Our results confirm the existence of phase space snail shells (or phase spirals) from 6–12 kpc. We find that grouping stars by the guiding radius (R _g ), instead of the present radius (R), further enhances the snail shell signal in the following aspects: (1) clarity of the snail shell shape is increased; (2) more wraps of the snail shell can be seen; (3) the phase spaces are less affected by the lack of stars closer to the disk midplane due to extinction; and (4) the phase space snail shell is amplified in greater radial ranges. Compared to the R-based snail shell, the quantitatively measured shapes are similar, except that the R _g -based snail shells show more wraps with a better contrast. These lines of evidence lead to the conclusion that the guiding radius (angular momentum) is a fundamental parameter tracing the phase space snail shell across the Galactic disk. Results of our test particle simulations with impulse approximation verify that particles grouped according to R _g reveal well-defined and sharper snail shell features. By comparing the radial profiles of the snail shell pitch angle between the observation and simulation, the external perturbation can be constrained to ∼500−700 Myr ago. For future vertical phase mixing study, it is recommended to use the guiding radius with additional constraints on orbital hotness (ellipticity) to improve the clarity of the phase snail.

通过结合大天空区域多目标光纤光谱望远镜和盖亚数据，我们研究了整个银河盘的垂直相位混合。我们的结果证实了 6-12 kpc 的相空间蜗牛壳（或相螺线）的存在。我们发现，通过引导半径（R _g）而不是当前半径（R）对恒星进行分组，在以下方面进一步增强了蜗牛壳信号：（1）增加了蜗牛壳形状的清晰度；(2)可以看到更多的蜗牛壳包裹；(3) 由于消光，靠近圆盘中平面的恒星较少，相空间受到的影响较小；(4)相空间蜗牛壳在更大的径向范围内被放大。与R相比 基于R _g的蜗牛壳，定量测量的形状相似，只是基于R _g的蜗牛壳显示出更多的包裹，具有更好的对比度。这些证据得出的结论是，引导半径（角动量）是一个基本参数，可以追踪穿过银河盘的相空间蜗牛壳。我们使用脉冲近似的测试粒子模拟结果验证了粒子根据R _g分组 揭示定义明确且更清晰的蜗牛壳特征。通过比较观察和模拟之间蜗牛壳俯仰角的径向轮廓，可以将外部扰动限制在~500-700 Myr 之前。对于未来的垂直相位混合研究，建议使用带有轨道热度（椭圆度）附加约束的引导半径，以提高相位蜗牛的清晰度。