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arXiv 1604.04022astro-ph.GA
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用SHARC-II在350微米观测到的低质量恒星形成核心目录

A Catalog of Low-Mass Star-Forming Cores Observed with SHARC-II at 350 microns

Akshaya Suresh, Michael M. Dunham, Héctor G. Arce, Neal J. Evans, Tyler L. Bourke, Manuel Merello, Jingwen Wu

摘要:

我们提出了一个目录的低质量致密的核心观察SHARC-II仪器在350微米。我们的观测具有10”的有效角分辨率,比赫歇尔空间天文台在相同波长下获得的观测高约2.5倍,尽管灵敏度较低,特别是对扩展发射。该目录包括81张地图,涵盖总共164个探测到的源。对于每个检测到的源,我们列出基本的源属性,包括位置,峰值强度,固定孔径的通量密度,和半径。我们研究了指向模型应用于所有SHARC-II数据的不确定性,保守地发现,模型校正在~3”内,大约是SHARC-II波束的1/3。我们研究了两种阵列扫描模式之间的差异,发现仪器校准,光束大小和光束形状在两种模式之间是相似的。我们还表明,相同的通量密度测量时,在两种不同的模式下观察到的源,这表明有没有系统的影响引入到我们的目录,利用两种不同的扫描模式在进行观测的过程中。我们发现原恒星核心的检测率为95%,但只有45%的无星核心,并证明存在SHARC-II检测偏见,但最大规模和紧凑的无星核心。最后,我们讨论了这些350微米的观测使原恒星分类的改进。

英文摘要:

We present a catalog of low-mass dense cores observed with the SHARC-II instrument at 350 microns. Our observations have an effective angular resolution of 10", approximately 2.5 times higher than observations at the same wavelength obtained with the Herschel Space Observatory, albeit with lower sensitivity, especially to extended emission. The catalog includes 81 maps covering a total of 164 detected sources. For each detected source, we tabulate basic source properties including position, peak intensity, flux density in fixed apertures, and radius. We examine the uncertainties in the pointing model applied to all SHARC-II data and conservatively find that the model corrections are good to within ~3", approximately 1/3 of the SHARC-II beam. We examine the differences between two array scan modes and find that the instrument calibration, beam size, and beam shape are similar between the two modes. We also show that the same flux densities are measured when sources are observed in the two different modes, indicating that there are no systematic effects introduced into our catalog by utilizing two different scan patterns during the course of taking observations. We find a detection rate of 95% for protostellar cores but only 45% for starless cores, and demonstrate the existence of a SHARC-II detection bias against all but the most massive and compact starless cores. Finally, we discuss the improvements in protostellar classification enabled by these 350 micron observations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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