论文标题
用辐射和风塑造GMC的结构
Shaping the structure of a GMC with radiation and winds
论文作者
论文摘要
我们通过3D辐射传递，实现具有$ {\ rm H} _2 _2 $形成和毁灭性的复杂化学网络的恒星反馈反馈（光电解离/电离，辐射压力和风）对巨型分子云（GMC）演变的影响。我们跟踪具有质量$ M> 1 \，{\ rm m} _ \ odot $的单个恒星的形成。每个恒星根据其光谱散发辐射，并用10个光子垃圾箱从近红外到极端的紫色带进行采样；风是通过邻近细胞中的能量注入来实现的。在不同气相的演变之后，我们对具有质量$ M = 10^5 \质量M = 10^5 \的GMC进行了模拟。由于同时包含了不同的恒星反馈机制，我们在云演化中确定了两个阶段：（1）辐射和风在巨大的恒星周围雕刻，低密度的气泡，而FUV辐射分离大多数$ {\ rm h} _2 _2 _2 _2 _2 _2 _2 _2 $，除了密集的，自我自我固定的clumps clumps clumps clumps clumps clumps clumps clumps clumps clumps clumps clumps clumps clumps clumpss clumps clumps; （2）快速星形形成（sfr $ \ simeq 0.1 \，{\ rm m} _ \ odot \，{\ rm yr}^{ - 1} $）在浓稠的团块中消耗分子气体，因此UV辐射Escapes并在GMC中降低了剩余的HI GOP。 $ {\ rm H} _2 $以$ 1.6 $ MYR的用尽，最终星形构造效率为36％。 FUV和电离场的平均强度几乎随着时间而稳定地增加。在模拟的结尾（$ t = 2.5 $ myr）时，我们发现$ \ langle g_0 \ rangle \ simeq 10^3 $（在habing单位中）和一个电离参数$ \ langle u _ {\ rm ion ion} \ rm ion} \ rangle \ rangle \ rangle \ rangle \ simeq 10^2^2 $。与GMC中的FUV相比，离子化场还具有更斑驳的分布。在整个演变中，从云中电离光子的逃生分数为$ f _ {\ rm ion，esc} <0.03 $。
We study the effect of stellar feedback (photodissociation/ionization, radiation pressure and winds) on the evolution of a Giant Molecular Cloud (GMC), by means of a 3D radiative transfer, hydro-simulation implementing a complex chemical network featuring ${\rm H}_2$ formation and destruction. We track the formation of individual stars with mass $M>1\,{\rm M}_\odot$ with a stochastic recipe. Each star emits radiation according to its spectrum, sampled with 10 photon bins from near-infrared to extreme ultra-violet bands; winds are implemented by energy injection in the neighbouring cells. We run a simulation of a GMC with mass $M=10^5\,{\rm M}_\odot$, following the evolution of different gas phases. Thanks to the simultaneous inclusion of different stellar feedback mechanisms, we identify two stages in the cloud evolution: (1) radiation and winds carve ionized, low-density bubbles around massive stars, while FUV radiation dissociates most ${\rm H}_2$ in the cloud, apart from dense, self-shielded clumps; (2) rapid star formation (SFR$\simeq 0.1\,{\rm M}_\odot\,{\rm yr}^{-1}$) consumes molecular gas in the dense clumps, so that UV radiation escapes and ionizes the remaining HI gas in the GMC. ${\rm H}_2$ is exhausted in $1.6$ Myr, yielding a final star formation efficiency of 36 per cent. The average intensity of FUV and ionizing fields increases almost steadily with time; by the end of the simulation ($t=2.5$ Myr) we find $\langle G_0 \rangle \simeq 10^3$ (in Habing units), and a ionization parameter $\langle U_{\rm ion} \rangle \simeq 10^2$, respectively. The ionization field has also a more patchy distribution than the FUV one within the GMC. Throughout the evolution, the escape fraction of ionizing photons from the cloud is $f_{\rm ion, esc} < 0.03$.
