论文标题
星系合并可以迅速关闭星形形成
Galaxy mergers can rapidly shut down star formation
论文作者
论文摘要
银河合并触发了恒星形成和积聚到中央超级黑洞。由于随后的能量反馈过程，长期以来一直有人提出，在银河系合并残留物中可以立即熄灭恒星形成。但是，最近对后期合并的广泛，快速淬火的预测最近受到了现代模拟的质疑，从未经过观察测试。在这里，我们对合并序列中长期预测的终点进行了第一次经验评估。基于从红外光学北部调查（工会）近距离紫外线鉴定出的〜500个后培现料的样本，我们表明，在先前的Starburst之后迅速关闭其星形形成的合并后星系的频率是从非混合星系的对照样品中预期的30-60倍。在紧密的星系对样本中未发现这种过量，这表明合并确实可以导致恒星形成迅速停止，但是此过程仅在聚结后才表现出来。
Galaxy mergers trigger both star formation and accretion onto the central supermassive black hole. As a result of subsequent energetic feedback processes, it has long been proposed that star formation may be promptly extinguished in galaxy merger remnants. However, this prediction of widespread, rapid quenching in late stage mergers has been recently called into question with modern simulations and has never been tested observationally. Here we perform the first empirical assessment of the long-predicted end phase in the merger sequence. Based on a sample of ~500 post-mergers identified from the Ultraviolet Near Infrared Optical Northern Survey (UNIONS), we show that the frequency of post-merger galaxies that have rapidly shutdown their star formation following a previous starburst is 30-60 times higher than expected from a control sample of non-merging galaxies. No such excess is found in a sample of close galaxy pairs, demonstrating that mergers can indeed lead to a rapid halt to star formation, but that this process only manifests after coalescence.
