3D radiative transfer modelling and virial analysis of starless cores in the B10 region of the Taurus molecular cloud
3D radiative transfer modelling and virial analysis of starless cores in the B10 region of the Taurus molecular cloud
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金牛座分子云 B10 区域无星核心的 3D 辐射传输建模和维里分析
DOI：
10.1093/mnras/stad827
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发表时间：
2023
影响因子：
4.8
通讯作者：
Caselli, Paola
中科院分区：
文献类型：
--
作者：
Scibelli, Samantha;Shirley, Yancy;Schmiedeke, Anika;Svoboda, Brian;Singh, Ayushi;Lilly, James;Caselli, Paola
像我们的太阳这样的低质量恒星是在气体和尘埃的冷核(10K)和致密核(∼105 cm−3)中开始演化的。无星地核的物理结构最好是通过尘埃颗粒的热发射来探测。我们给出了金牛座分子云B10区无星核心的高分辨率尘埃连续谱研究。在IRAM 30m上用NIKA2仪器在1.2和2.0 mm(12和18角秒分辨率)进行的新观测，探测了14个低质量无恒星核的内部区域。我们通过使用RADMC-3D的辐射传输框架Pandora，对这些岩芯中的每一个进行复杂的3D辐射传输建模。模型最适合约束每个核心的中心密度、密度斜率、纵横比、不透明度和星际辐射场强度。这些在B10中的“典型”核心的中心密度从5× 104到1× 106 cm−3，平均值为2.6x 105 cm−3。我们发现3D模拟中假定的尘埃不透明度规律以及Herschel估计的尘埃发射率指数β‘S位于分布的低端，直接由NIKA2图约束，其平均值为β=2.01x±0.48。根据我们的3D密度结构和NH3档案数据，我们执行自洽维里分析来评估每个核心的稳定性。在忽略磁场贡献的情况下，我们发现14个核心中有9个(： %)要么处于维里平衡状态，要么受到重力和外部压力的约束。要将受约束的磁芯推回到平衡状态，只需要15g∼的有效磁场差即可。
Low-mass stars like our Sun begin their evolution within cold (10 K) and dense (∼105cm−3) cores of gas and dust. The physical structure of starless cores is best probed by thermal emission of dust grains. We present a high-resolution dust continuum study of the starless cores in the B10 region of the Taurus Molecular Cloud. New observations at 1.2 and 2.0 mm (12 and 18 arcsec resolution) with the NIKA2 instrument on the IRAM 30m have probed the inner regions of 14 low-mass starless cores. We perform sophisticated 3D radiative transfer modelling for each of these cores through the radiative transfer frameworkpandora, which utilizes RADMC-3D. Model best-fits constrain each cores’ central density, density slope, aspect ratio, opacity, and interstellar radiation field strength. These ‘typical’ cores in B10 span central densities from 5 × 104to 1 × 106cm−3, with a mean value of 2.6 × 105cm−3. We find the dust opacity laws assumed in the 3D modelling, as well as the estimates fromHerschel, have dust emissivity indices, β’s, on the lower end of the distribution constrained directly from the NIKA2 maps, which averages to β = 2.01 ± 0.48. From our 3D density structures and archival NH3data, we perform a self-consistent virial analysis to assess each core’s stability. Ignoring magnetic field contributions, we find nine out of the 14 cores (64 per cent) are either in virial equilibrium or are bound by gravity and external pressure. To push the bounded cores back to equilibrium, an effective magnetic field difference of only ∼15G is needed.