发表机构
University of Vienna; Faculty of Physics, Martí i Franquès, 1-11, 08028 Barcelona, Spain; Astronomical Institute of the Czech Academy of Sciences; Center for Astrophysics | Harvard & Smithsonian; European Southern Observatory（维也纳大学; 巴塞罗那大学物理学院; 捷克科学院天文研究所; 哈佛-史密森尼天体物理中心; 欧洲南方天文台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究利用高分辨率年龄图重建猎户座恒星形成历史，发现四个间隔约5百万年的增强期，其中两个主要时期包含约59%的恒星，且与邻近Sco-Cen区域的时间尺度一致，表明恒星形成具有结构化和间歇性特征。
AI 中文摘要
恒星形成在分子云复合体中的传播可以告诉我们很多关于其物理驱动因素以及环境过程与内在过程相对重要性的信息。我们利用目前可用的最高分辨率年龄图重建了猎户座恒星形成复合体的恒星形成历史（SFH）。该图包含由SigMA聚类算法识别的47个共空间且共运动的星群，具有均匀推导的年龄和星群成员资格。我们发现了四个恒星形成增强时期，每个时期相隔约5百万年。两个增强最显著的时期，分别在6.4百万年和11.3百万年，可以在统计上被定位，合计包含约59%的恒星，并且对重采样和年龄拟合的变化具有稳健性。两个较老且较小的增强时期，分别在16.2百万年和21.4百万年，可以在年龄分布中识别出来，但目前无法证明其稳健性。恒星形成增强时期之间约5百万年的间隔与附近的天蝎-半人马（Sco-Cen）恒星形成区域发现的间隔相同。我们没有发现可能产生这种SFH结构的方法论偏差。我们识别出了时空上相连的结构，包括三个星链候选体。我们得出结论，猎户座中的恒星形成似乎发生在与Sco-Cen相同的时间尺度上，但模式不同。约5百万年间隔的原因仍然是个谜，在两个不同的恒星形成区域中检测到这一现象需要进一步研究。
英文摘要
The propagation of star formation throughout a molecular cloud complex can tell us much about its physical drivers and the importance of environmental versus intrinsic processes. We reconstruct the star formation history (SFH) of the Orion star-forming complex using the highest-resolution age map currently available. It comprises 47 co-spatial and co-moving groups identified by the SigMA clustering algorithm, with homogeneously derived ages and group memberships. We find four periods of increased star formation, separated by ~5 Myr each. The two periods of highest increase, at 6.4 and 11.3 Myr, can be statistically localized, together hold ca. 59% of all stars, and are robust against resampling and changes to the age fitting. The two older, smaller increases at 16.2 and 21.4 Myr can be identified in the age distribution, but cannot be shown to be robust at this point. The ~5 Myr spacing between the episodes of increased star formation is the same as found for the nearby Scorpius-Centaurus (Sco-Cen) star-forming region. We find no methodological bias that could produce the SFH structure. We identify spatio-temporally connected structures, including three cluster-chain candidates. We conclude that star formation in Orion seems to occur on the same timescales but with a different pattern than in Sco-Cen. The cause of the ~5 Myr separations remains a mystery, and its detection in two distinct star-forming regions needs further investigation.
Comments4 pages, 9 figures, 5 pages appendix. Submitted to A&A Letters. Comments welcome
