基于LAMOST和Gaia DR3探测银河系盘翘曲的进动

Precession Detection of Galactic Disk Warp Based on LAMOST and Gaia DR3

过去对银河系盘恒星的分析表明,恒星盘存在一个明显的非对称翘曲结构。基于LAMOST DR5和Gaia DR3的运动学数据,利用大约23000颗红团簇星样本和一个运动学模型,对翘曲的进动进行了量化分析。通过比较不同翘曲模型的翘曲进动值,发现翘曲的进动与模型中振动幅度可能存在关联。最后,应用一个基于Gaia DR2的翘曲模型,计算得到翘曲进动的最佳拟合值β=4.32±0.8 km·s^(-1)·kpc^(-1)。

Previous analysis of galactic disk stars have shown that there is an obvious asymmetric warp structure in the stellar disk.Based on the kinematics data of LAMOST DR5 and Gaia DR3,a sample of 23000 red clump stars is utilized to quantitatively analyze the precession of warp by kinematics model.It is found that the warp precession may be related to the warp amplitude in the model by comparing the warp precession values of different warp models.Finally,a warp model based on Gaia DR2 is applied to calculate the best fitting value of warp precession,which isβ=4.32±0.8 km·s^(-1)·kpc^(-1).