近日，日本名古屋大学Shuo Huang团队揭示了早期宇宙中由成熟的星系棒驱动的大量气体流入。2025年5月21日，《自然》杂志发表了这一成果。

棒结构存在于大约一半的局部盘状星系中，在长期星系演化中起着关键作用。棒对旋转的圆盘施加非轴对称的扰动，并向内输送气体，为中心星爆提供能量，并可能为核超大质量黑洞的活动提供能量。它们被认为是长寿命的结构，现在被确定为红移z > 2。然而，人们对宇宙早期条形的开始和影响知之甚少，因为以足够的分辨率对遥远条形进行光谱分析的成本过高。 

研究组报告了一项关于大爆炸后26亿年红移2.467处星系棒的运动学研究。他们观察了尘埃恒星形成星系J0107a的一氧化碳和原子碳排放线，发现J0107a条的气体分布和运动模式与局部条相同。与此同时，该杆驱动着主导圆盘旋转的大规模非圆形运动，以每年约600太阳质量的速度将分子气体汇集到其中心。该研究结果表明，111亿年前，棒驱动的动力学过程和长期演化已经在发挥作用，在一个巨大的盘状星系中，在富含气体和远红外发光的生长阶段，为活跃的恒星形成提供了动力。

附：英文原文

Title: Large gas inflow driven by a matured galactic bar in the early Universe

Author: Huang, Shuo, Kawabe, Ryohei, Umehata, Hideki, Kohno, Kotaro, Tamura, Yoichi, Saito, Toshiki

Issue&Volume: 2025-05-21

Abstract: Bar structures are present in about half of local disk galaxies1 and play pivotal roles in secular galaxy evolution. Bars impose a non-axisymmetric perturbation on the rotating disk and transport gas inwards to feed the central starburst and, possibly, the activity of the nuclear supermassive black hole2. They are believed to be long-lived structures3,4 and are now identified at redshift z>2 (refs. 5,6). However, little is known about the onset and effects of bars in the early cosmic epoch because the spectroscopy of distant bars at sufficient resolution is prohibitively expensive. Here we report on a kinematic study of a galactic bar at redshift 2.467, 2.6 billion years after the Big Bang. We observed the carbon monoxide and atomic carbon emission lines of the dusty star-forming galaxy J0107a and found the bar of J0107a has gas distribution and motion in a pattern identical to local bars7,8,9. At the same time, the bar drives large-scale non-circular motions that dominate over disk rotation, funnelling molecular gas into its centre at a rate of approximately 600 solar masses per year. Our results show that bar-driven dynamical processes and secular evolution were already at play 11.1 billion years ago, powering active star formation amid the gas-rich and far-infrared luminous growth phase in a massive disk galaxy.

DOI: 10.1038/s41586-025-08914-2

Source: https://www.nature.com/articles/s41586-025-08914-2