Galaxy internal structure growth has long been accused of inhibiting star formation in disc galaxies. We investigate the potential physical connection between the growth of dispersion-supported stellar structures (e.g. classical bulges) and the position of galaxies on the star-forming main sequence at z ∼ 0. Combining the might of the SAMI and MaNGA galaxy surveys, we measure the λRe spin parameter for 3289 galaxies over $9.5 \lt \log M_{\star } [\rm {M}_{\odot }] \lt 12$. At all stellar masses, galaxies at the locus of the main sequence possess λRe values indicative of intrinsically flattened discs. However, above $\log M_{\star }[\rm {M}_{\odot }]\sim 10.5$ where the main sequence starts bending, we find tantalizing evidence for an increase in the number of galaxies with dispersion-supported structures, perhaps suggesting a connection between bulges and the bending of the main sequence. Moving above the main sequence, we see no evidence of any change in the typical spin parameter in galaxies once gravitationally interacting systems are excluded from the sample. Similarly, up to 1 dex below the main sequence, λRe remains roughly constant and only at very high stellar masses ($\log M_{\star }[\rm {M}_{\odot }]\gt 11$), do we see a rapid decrease in λRe once galaxies decline in star formation activity. If this trend is confirmed, it would be indicative of different quenching mechanisms acting on high- and low-mass galaxies. The results suggest that whilst a population of galaxies possessing some dispersion-supported structure is already present on the star-forming main sequence, further growth would be required after the galaxy has quenched to match the kinematic properties observed in passive galaxies at z ∼ 0.

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关于恒星形成主序星系恒星运动学的 SAMI 和 MaNGA 观点

长期以来，星系内部结构的增长一直被指责为抑制圆盘星系中的恒星形成。我们研究了色散支持的恒星结构（例如经典核球）的生长与星系在 z ∼ 0 处的恒星形成主序列上的位置之间的潜在物理联系。结合 SAMI 和 MaNGA 星系调查的力量，我们测量3289 个星系的 λRe 自旋参数超过 $9.5 \lt \log M_{\star } [\rm {M}_{\odot }] \lt 12$。在所有恒星质量下，位于主序星点的星系都具有 λRe 值，表明其本质上是扁平的圆盘。然而，在 $\log M_{\star }[\rm {M}_{\odot }]\sim 10.5$ 以上主序开始弯曲的地方，我们发现了具有色散支持的星系数量增加的诱人证据结构，也许暗示了凸起和主序曲弯曲之间的联系。移动到主序列之上，一旦从样本中排除了引力相互作用系统，我们没有看到星系中典型自旋参数有任何变化的证据。类似地，在主序列下方最多 1 dex，λRe 大致保持不变，并且仅在非常高的恒星质量 ($\log M_{\star }[\rm {M}_{\odot }]\gt 11$) 处，做一旦星系的恒星形成活动下降，我们就会看到 λRe 的快速下降。如果这一趋势得到证实，这将表明不同的淬火机制作用于高质量和低质量星系。结果表明，虽然拥有某种色散支持结构的星系群已经存在于恒星形成的主序带上，