论文标题
猎户座中的膨胀气泡：[CII] M42，M43和NGC 1977的观察结果
Expanding bubbles in Orion A: [CII] observations of M42, M43, and NGC 1977
论文作者
论文摘要
猎户座分子云是最近的大型明星形成区域。由于强烈的辐射场和恒星风，大量恒星对环境产生了深远的影响。 [CII] $ 158 \，μ\ Mathrm {M} $良好结构线的速度分辨观察结果使我们能够研究紫外线鲜艳的气体的运动学。在这里，我们提出了一张平方度尺寸的图表，该图是由orion nebula综合体获得的[CII]发射的，覆盖了整个Orion Nebula（M42）加M43和Nebulae NGC 1973，1973，1975和1977和1977年，我们比较了这三个区域的范围。 O7V星$θ^1 $ ori C吹出的气泡迅速扩展，$ 13 \，\ mathrm {km \，s^{ - 1}} $。简单的分析模型重现了这种风吹气气泡的热内气和中性外壳的特性，并使我们估计了$ 0.2 \，\ mathrm {myr {Myr} $的膨胀时间。 M43带有B0.5V星Nu Ori也表现出扩展的气泡结构，其膨胀速度为$ 6 \，\ mathrm {km \，s^{ - 1}} $。与H \，{\ sc ii}区域的压力驱动扩展的分析模型的比较，给出了$ 0.02 \，\ mathrm {myr} $的年龄估计值。 NGC 1973、1975和1977年与中央B1V星星42 Orionis围绕着$ 1.5 \，\ Mathrm {km \，S^{ - 1}} $扩展的气泡，可能是由于M43的情况过度压印的电离气体。对于此结构，我们的年龄为$ 0.4 \，\ mathrm {myr} $。我们得出的结论是，强烈的恒星风从$θ^1 $ ori C驱动了猎户座星云的气泡，而与M43和NGC 1977相关的气泡是由由于其中央后期大型恒星离子化的热量膨胀引起的。
The Orion Molecular Cloud is the nearest massive-star forming region. Massive stars have profound effects on their environment due to their strong radiation fields and stellar winds. Velocity-resolved observations of the [CII] $158\,μ\mathrm{m}$ fine-structure line allow us to study the kinematics of UV-illuminated gas. Here, we present a square-degree-sized map of [CII] emission from the Orion Nebula complex obtained by the upGREAT instrument onboard SOFIA, covering the entire Orion Nebula (M42) plus M43 and the nebulae NGC 1973, 1975, and 1977. We compare the stellar characteristics of these three regions with the kinematics of the expanding bubbles surrounding them. The bubble blown by the O7V star $θ^1$ Ori C in the Orion Nebula expands rapidly, at $13\,\mathrm{km\,s^{-1}}$. Simple analytical models reproduce the characteristics of the hot interior gas and the neutral shell of this wind-blown bubble and give us an estimate of the expansion time of $0.2\,\mathrm{Myr}$. M43 with the B0.5V star NU Ori also exhibits an expanding bubble structure, with an expansion velocity of $6\,\mathrm{km\,s^{-1}}$. Comparison with analytical models for the pressure-driven expansion of H\,{\sc ii} regions gives an age estimate of $0.02\,\mathrm{Myr}$. The bubble surrounding NGC 1973, 1975, and 1977 with the central B1V star 42 Orionis expands at $1.5\,\mathrm{km\,s^{-1}}$, likely due to the over-pressurized ionized gas as in the case of M43. We derive an age of $0.4\,\mathrm{Myr}$ for this structure. We conclude that the bubble of the Orion Nebula is driven by the mechanical energy input by the strong stellar wind from $θ^1$ Ori C, while the bubbles associated with M43 and NGC 1977 are caused by the thermal expansion of the gas ionized by their central later-type massive stars.
