论文标题
在NGC 253中的原始恒星群集13的热结构上
On the thermal structure of the proto-Super Star Cluster 13 in NGC 253
论文作者
论文摘要
使用高角度分辨率ALMA观察（$ 0.02^{\ Prime \ prime} \大约0.34 $ PC），我们研究了NGC253中央地区的Proto Super Super Star Cluster $ 13 $ 13 $的热结构和运动学，并通过其连续性和振动的HC $ _3 $ _3 $ _3 $ n $ _3 $ j = 24-23 = 24-23至$ v_4 = 1 $。我们携带了HC $ _3 $ N的径向轮廓的2D-LTE和非本地辐射转移模型，并以0.1 $ PC宽度为0.1 $的同心环。从2D-LTE分析中，我们在SE-NW方向上发现了具有很高的振动温度（$> 500 $ k）的超级热核（SHC），具有很高的振动温度（$> 500 $ K）（$> 500 $ k），并以径向速度（$ 21 $ km S $^{ - 1} $）跳跃。从非本地模型中，我们得出HC $ _3 $ N列密度，H $ _2 $密度和灰尘温度（$ t_ \ text {dust} $）配置文件。我们的结果表明，由于IR的高灰尘不透明度，SHC的热结构由温室效应主导，导致LTE $ T_ \ text {dust {dust} $及其派生的发光度高估了。 SHC的运动学和$ t_ \ text {dust {dust} $配置文件表明，恒星形成很可能是由云云碰撞触发的。我们将Proto-SSC $ 13 $与其他深层嵌入的星形形成区域进行比较，并讨论$ l_ \ text {ir}/m _ {\ text {h} _2} $多余的$ \ sim100 $ l $ _ \ odot $ _ \ odot $ m $ m $ _ _ \ odot^{ - odot^{ - 1} $ obs（uive）
Using high angular resolution ALMA observations ($0.02^{\prime\prime}\approx0.34$ pc), we study the thermal structure and kinematics of the proto super star cluster $13$ in the central region of NGC253 through their continuum and vibrationally excited HC$_3$N emission from $J=24-23$ and $J=26-25$ lines arising from vibrational states up to $v_4=1$. We have carried 2D-LTE and non-local radiative transfer modelling of the radial profile of the HC$_3$N and continuum emission in concentric rings of $0.1$ pc width. From the 2D-LTE analysis, we found a Super Hot Core (SHC) of $1.5$ pc with very high vibrational temperatures ($>500$ K), and a jump in the radial velocity ($21$ km s$^{-1}$) in the SE-NW direction. From the non-local models, we derive the HC$_3$N column density, H$_2$ density and dust temperature ($T_\text{dust}$) profiles. Our results show that the thermal structure of the SHC is dominated by the greenhouse effect due to the high dust opacity in the IR, leading to an overestimation of the LTE $T_\text{dust}$ and its derived luminosity. The kinematics and $T_\text{dust}$ profile of the SHC suggest that star formation was likely triggered by a cloud-cloud collision. We compare proto-SSC $13$ to other deeply embedded star-forming regions, and discuss the origin of the $L_\text{IR}/M_{\text{H}_2}$ excess above $\sim100$ L$_\odot$ M$_\odot^{-1}$ observed in (U)LIRGs.
