近日，英国杜伦大学的Anna F. McLeod与美国弗罗里达大学的Adam Ginsburg以及德国杜伊斯堡-埃森大学的Rolf Kuiper等人合作并取得一项新进展。经过不懈努力，他们发现一个潜在的开普勒星盘正在为光学显示的大质量年轻恒星供给物质。相关研究成果已于2023年11月29日在国际权威学术期刊《自然》上发表。

该研究团队在大麦哲伦星云的星系外发现了一个围绕大质量年轻恒星体（MYSOs）的旋转气体结构。气体运动的研究结果表明，存在一种径向物质流，从大尺度范围内流向中心的圆盘状结构。该圆盘状结构呈现出开普勒旋转的特征，因此存在一个旋转的环面，为吸积盘提供物质，从而促进中央恒星的生长。这个系统与银河系内的高质量年轻恒星体（YSOs）在许多方面相似，这些YSOs也是通过开普勒盘吸积气体。

然而，与银河系中的类似系统相比，这个源在光学上可见，而不是像通常预期的那样被深深地嵌入在其原始物质中。研究人员认为，这是恒星在低金属丰度和低尘埃含量环境中形成的结果。因此，这些发现为大质量恒星及其星周盘的形成和演化模型提供了重要的约束。

据悉，恒星形成的传统观念包含由星盘引导的吸积过程、开普勒吸积盘以及相关的双极喷流，这些现象主要出现在附近的低质量年轻恒星体（YSOs）中。近期，研究人员在几个大质量（质量超过8倍太阳质量）的YSOs（MYSOs）周围观测到了旋转的气体构造和开普勒盘，其中包括一些星盘喷流系统。目前已知的所有MYSO系统均位于银河系内，且它们都被其原始物质所包裹。

附：英文原文

Title: A probable Keplerian disk feeding an optically revealed massive young star

Author: McLeod, Anna F., Klaassen, Pamela D., Reiter, Megan, Henshaw, Jonathan, Kuiper, Rolf, Ginsburg, Adam

Issue&Volume: 2023-11-29

Abstract: The canonical picture of star formation involves disk-mediated accretion, with Keplerian accretion disks and associated bipolar jets primarily observed in nearby, low-mass young stellar objects (YSOs). Recently, rotating gaseous structures and Keplerian disks have been detected around several massive (M>8M_⊙) YSOs (MYSOs), including several disk-jet systems. All the known MYSO systems are in the Milky Way, and all are embedded in their natal material. Here we report the detection of a rotating gaseous structure around an extragalactic MYSO in the Large Magellanic Cloud. The gas motion indicates that there is a radial flow of material falling from larger scales onto a central disk-like structure. The latter exhibits signs of Keplerian rotation, so that there is a rotating toroid feeding an accretion disk and thus the growth of the central star. The system is in almost all aspects comparable to Milky Way high-mass YSOs accreting gas from a Keplerian disk. The key difference between this source and its Galactic counterparts is that it is optically revealed rather than being deeply embedded in its natal material as is expected of such a massive young star. We suggest that this is the consequence of the star having formed in a low-metallicity and low-dust content environment. Thus, these results provide important constraints for models of the formation and evolution of massive stars and their circumstellar disks.

DOI: 10.1038/s41586-023-06790-2

Source: https://www.nature.com/articles/s41586-023-06790-2