AI 中文总结
该研究利用SAMI星系巡天数据，通过偏相关分析等方法，量化星系属性对自旋参数$\lambda_{\rm{R_e}}$的影响。发现形态学指标相关性最强，能较好解释$\lambda_{\rm{R_e}}$分布，为星系自旋统计推断可行性研究提供依据。
AI 中文摘要
自旋参数$\lambda_{\rm{R_e}}$是星系特定恒星角动量的代理，也是分类运动形态的有用指标。本研究旨在利用悉尼 - AAO多目标积分场光谱仪（SAMI）星系巡天数据量化星系属性在解释$\lambda_{\rm{R_e}}$时的相对重要性。应用偏相关分析和偏最小二乘回归评估不同参数对$\lambda_{\rm{R_e}}$的贡献。发现形态学指标，即一个有效半径内的 bulge - 总比（$B/T_\rm{e}$）和椭圆率（$\varepsilon_\rm{e}$）与$\lambda_{\rm{R_e}}$相关性最强，在回归分析中起主导作用，这从统计上证实了已确立的快速旋转序列。轻加权年龄和恒星质量也有显著相关性，但在多变量分析中其贡献次于形态学指标。还研究了仅用星系属性能否重现$\lambda_{\rm{R_e}}$的观测趋势。形态学指标能重现观测到的$\lambda_{\rm{R_e}}$的总体分布，散射约为0.12，纳入年龄和恒星质量仅有适度改善，且不能很好地重现慢速旋转状态。总体而言，结果表明光度结构参数最能解释$\lambda_{\rm{R_e}}$，并暗示随着模型改进和参数集扩大，从非IFS可观测值进行星系自旋的统计推断可能可行。
英文摘要
The spin parameter $λ_{\rm{R_e}}$ is a proxy for the specific stellar angular momentum of galaxies and is a useful metric for classifying kinematic morphology. This study aims to quantify the relative importance of galaxy properties in explaining $λ_{\rm{R_e}}$, using data from the Sydney-AAO Multi-object Integral-field spectrograph (SAMI) Galaxy Survey. We apply partial correlation analysis and partial least squares regression to assess the relative contributions of different parameters in explaining $λ_{\rm{R_e}}$. We find that morphology indicators, bulge-to-total ratio within one effective radius ($B/T_\rm{e}$) and ellipticity ($\varepsilon_\rm{e}$), show the strongest correlations with $λ_{\rm{R_e}}$ and play a leading role in the regression analysis. This result statistically confirms the established fast-rotator sequence, in which fast-rotating early-type galaxies form a continuous structural and kinematic sequence with spiral galaxies, with $λ_{\rm{R_e}}$ decreasing as bulge prominence increases. The light-weighted age and stellar mass also exhibit significant correlations, but their contributions are secondary to the morphology indicators in multivariate analyses. We also examine whether the observed trends in $λ_{\rm{R_e}}$ can be reproduced using galaxy properties alone. The morphology indicators (${B/T_\rm{e}}$, $\varepsilon_\rm{e}$) reproduce the overall distribution of observed $λ_{\rm{R_e}}$ with a scatter of about 0.12, while the inclusion of Age_LW and $M_\star$ provides only modest additional improvement. However, these relations do not reproduce the slow-rotator regime well. Overall, our results show that photometric structural parameters best explain $λ_{\rm{R_e}}$ and suggest that statistical inference of galaxy spin from non-IFS observables may become feasible with improved models and a broader set of parameters.
Comments15 pages, 6 figures, accepted for publication in MNRAS
