原恒星气泡 RCW 120 中的恒星反馈与触发恒星形成

Stellar feedback and triggered star formation in the prototypical bubble RCW 120.

作者信息

Luisi Matteo, Anderson Loren D, Schneider Nicola, Simon Robert, Kabanovic Slawa, Güsten Rolf, Zavagno Annie, Broos Patrick S, Buchbender Christof, Guevara Cristian, Jacobs Karl, Justen Matthias, Klein Bernd, Linville Dylan, Röllig Markus, Russeil Delphine, Stutzki Jürgen, Tiwari Maitraiyee, Townsley Leisa K, Tielens Alexander G G M

机构信息

Department of Physics and Astronomy, West Virginia University, Morgantown, WV 26506, USA.

Center for Gravitational Waves and Cosmology, West Virginia University, Chestnut Ridge Research Building, Morgantown, WV 26505, USA.

出版信息

Sci Adv. 2021 Apr 9;7(15). doi: 10.1126/sciadv.abe9511. Print 2021 Apr.

DOI:10.1126/sciadv.abe9511

PMID:33837081

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8034851/

Abstract

Radiative and mechanical feedback of massive stars regulates star formation and galaxy evolution. Positive feedback triggers the creation of new stars by collecting dense shells of gas, while negative feedback disrupts star formation by shredding molecular clouds. Although key to understanding star formation, their relative importance is unknown. Here, we report velocity-resolved observations from the SOFIA (Stratospheric Observatory for Infrared Astronomy) legacy program FEEDBACK of the massive star-forming region RCW 120 in the [CII] 1.9-THz fine-structure line, revealing a gas shell expanding at 15 km/s. Complementary APEX (Atacama Pathfinder Experiment) CO J = 3-2 345-GHz observations exhibit a ring structure of molecular gas, fragmented into clumps that are actively forming stars. Our observations demonstrate that triggered star formation can occur on much shorter time scales than hitherto thought (<0.15 million years), suggesting that positive feedback operates on short time periods.

摘要

大质量恒星的辐射和机械反馈调节着恒星形成和星系演化。正反馈通过收集密集的气体壳层触发新恒星的形成，而负反馈则通过撕裂分子云破坏恒星形成。尽管这对理解恒星形成至关重要，但其相对重要性尚不清楚。在这里，我们报告了平流层红外天文台（SOFIA）的遗产项目“反馈”对大质量恒星形成区域 RCW 120 在 [CII] 1.9太赫兹精细结构线的速度分辨观测结果，揭示了一个以15千米/秒速度膨胀的气体壳层。阿塔卡马探路者实验（APEX）的一氧化碳J = 3-2 345吉赫兹的补充观测显示出分子气体的环状结构，这些分子气体破碎成正在积极形成恒星的团块。我们的观测表明，触发恒星形成的时间尺度可能比迄今认为的要短得多（<15万年），这表明正反馈在短时间内起作用。