Evidence for a cloud-cloud collision in Sh2-233 triggering the formation of the high-mass protostar object IRAS 05358+3543
Evidence for a cloud-cloud collision in Sh2-233 triggering the formation of the high-mass protostar object IRAS 05358+3543
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Sh2-233 中云与云碰撞触发高质量原恒星天体 IRAS 05358 3543 形成的证据
DOI：
10.1093/mnras/stac1087
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发表时间：
2022
影响因子：
4.8
通讯作者：
Kisetsu
中科院分区：
文献类型：
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作者：
Yamada;Rin I. ; Fukui;Yasuo ; Sano;Hidetoshi ; Tachihara;Kengo ; Bieging;John H. ; Enokiya;Rei ; Nishimura;Atsushi ; Fujita;Shinij ; Kohno;Mikito ; Tsuge;Kisetsu
我们使用以 ∼0.5 pc 分辨率获取的 COJ= 2–1 数据对 Sh2-233 区域的分子气体进行了新的运动学分析。分子气体由长度为 5 pc、宽度为 1.5 pc 的丝状云组成，其中嵌入了两个致密的云核。细丝位于两片云之间，两片云的速度差为 2.7 km s−1，并且延伸超过 ∼5 pc。我们设想了这样一个场景：两朵云相互碰撞，并压缩它们之间的气体，形成垂直于碰撞的~0.5 Myr 的细丝。碰撞很可能不仅形成了丝状云，还形成了两个致密的核心。其中一个致密核心与大质量原恒星候选者 IRAS 05358+3543 相关，这是一种代表性的大质量原恒星。在高质量恒星形成的整体塌缩方案中，假设半径为 0.1 pc 的体积内有一个 100M 的致密核心作为初始条件，而这种核心的形成在之前的工作中仍然无法解释。我们认为，所提出的碰撞是一个有效地将 100M⊙ 气体收集到 0.1 pc 半径的步骤。这支持了云与云碰撞是形成紧凑的高质量致密核心 IRAS 05358+3543 的重要过程。
We have carried out a new kinematical analysis of the molecular gas in the Sh2-233 region by using the COJ= 2–1 data taken at ∼0.5 pc resolution. The molecular gas consists of a filamentary cloud of 5-pc length with 1.5-pc width where two dense cloud cores are embedded. The filament lies between two clouds, which have a velocity difference of 2.7 km s−1and are extended over ∼5 pc. We frame a scenario that the two clouds are colliding with each other and compressed the gas between them to form the filament in ∼0.5 Myr which is perpendicular to the collision. It is likely that the collision formed not only the filamentary cloud but also the two dense cores. One of the dense cores is associated with the high-mass protostellar candidate IRAS 05358+3543, a representative high-mass protostar. In the monolithic collapse scheme of high mass star formation, a compact dense core of 100M⊙within a volume of 0.1 pc radius is assumed as the initial condition, whereas the formation of such a core remained unexplained in the previous works. We argue that the proposed collision is a step which efficiently collects the gas of 100M⊙into 0.1 pc radius. This lends support for that the cloud–cloud collision is an essential process in forming the compact high-mass dense core, IRAS 05358+3543.