ROCKETS I：研究火箭效应对两个被红外泡包裹的邻近年轻疏散星团的影响
ROCKETS I: Investigating the Impact of the Rocket Effect on Two Nearby Young Open Clusters Encased in Infrared Bubbles
- Centre of Excellence in Astronomy and Astrophysics, Department of Physics and Electronics, CHRIST (Deemed to be University)（天体物理学与天文学卓越中心，物理与电子系，CHRIST（认定大学））
- Instituto de Estudios Astrofísicos, Facultad de Ingeniería y Ciencias, Universidad Diego Portales（天文研究所，工程与科学学院，迭戈帕托莱斯大学）
- Millennium Nucleus on Young Exoplanets and their Moons (YEMS)（年轻系外行星及其卫星千年核心（YEMS））
- Indian Institute of Astrophysics（印度天体物理研究所）
- Academia Sinica Institute of Astronomy and Astrophysics（中央研究院天文及天文物理研究所）
- National Astronomical Observatory of Japan, National Institutes of Natural Sciences（日本国立天文台，国立自然科学研究机构）
- St. Joseph’s College, Moolamattom（圣约瑟夫学院，穆拉马托姆）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究基于Gaia项目，以两个被红外泡包裹的年轻疏散星团为样本，通过相对自行角、火箭效应指数等分析，证实了火箭效应可驱动气体加速并触发恒星形成。
AI中文摘要：
我们推出ROCKETS（Rocket-driven Cluster Kinematics & Triggered Star-formation，即火箭驱动星团运动学与触发恒星形成），这是一项基于盖亚（Gaia）的项目，旨在研究年轻恒星形成区中恒星反馈或火箭效应的运动学特征。我们以两个邻近的基准区域Collinder 69和IC 1396为方法演示对象，分析了两个包含O型恒星且被中红外泡包裹的年轻星团。我们利用盖亚数据，在由I/II类年轻恒星天体（YSO）的中位数和中位数绝对偏差定义的天体测量椭圆内，选择共动候选体。对每颗恒星，我们计算其相对于电离源的相对自行角（RPMA）。在两个区域中，RPMA分布在RPMA <15°处均呈现显著过剩，对应于远离各自电离源运动的天体。我们通过火箭效应指数（REI）量化这一现象，发现Collinder 69的REI约为1.1，IC 1396的REI约为1.7；当仅考虑I/II类年轻恒星天体时，两个区域的REI均增至REI ≳10。对样本的速度结构分析显示，RPMA <15°的子集相比整个共动样本具有更强的正成对膨胀，为火箭效应提供了额外支持。向外运动的恒星并非均匀分布，其位置角呈现强烈各向异性，且优先朝向亮边缘云。盖亚色-星等图显示，向外运动的天体与文献中的星团成员之间无显著年龄偏移。观测到的运动学特征表明，火箭效应驱动气体加速，并优先向膨胀泡的高密度区域触发恒星形成。
英文摘要：
We introduce ROCKETS (Rocket-driven Cluster Kinematics & Triggered Star-formation), a Gaia based programme investigating kinematic fingerprints of stellar feedback or rocket effect in young star forming regions. We analyse two young clusters with O-type stars enclosed by mid-infrared bubbles, Collinder 69 and IC 1396 as a methodological demonstration on two nearby benchmark regions. Co-moving candidates are selected within an astrometric ellipse defined by the median and median absolute deviation of Class I/II YSOs with Gaia data. For each star, we compute a relative proper-motion angle (RPMA) relative to the ionising source. In both regions the RPMA distribution shows a strong excess at RPMA $<15^{\circ}$, corresponding to sources moving away from the respective ionising sources. We quantify this using the Rocket Effect Index (REI), finding $\mathrm{REI}\simeq 1.1$ for Collinder 69 and $\mathrm{REI}\simeq 1.7$ for IC 1396. When considering only Class I/II YSOs, the REI of both regions increases to $\mathrm{REI}\gtrsim 10$. Velocity-structure analysis of the sample shows that the RPMA $<15^\circ$ subset has stronger positive pairwise expansion than the full co-moving population, providing additional support for the rocket effect. The outward-moving stars are not uniformly distributed; instead, their position angles are strongly anisotropic and preferentially aligned towards the bright-rimmed clouds. Gaia colour-magnitude diagrams show no strong age offset between sources moving outward and literature cluster members. The observed kinematic signatures support feedback-driven acceleration of gas and triggered star formation preferentially towards higher density regions of expanding bubbles due to the rocket effect.
