The JCMT Gould Belt Survey: SCUBA-2 Data Reduction Methods and Gaussian Source Recovery Analysis
The JCMT Gould Belt Survey: SCUBA-2 Data Reduction Methods and Gaussian Source Recovery Analysis
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DOI：
10.3847/1538-4365/aada7f
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发表时间：
2018-08
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影响因子：
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通讯作者：
H. Kirk;J. Hatchell;D. Johnstone;D. Berry;T. Jenness;J. Buckle;S. Mairs;E. Rosolowsky;J. Francesc
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文献类型：
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作者：
H. Kirk;J. Hatchell;D. Johnstone;D. Berry;T. Jenness;J. Buckle;S. Mairs;E. Rosolowsky;J. Francesc
詹姆斯·克莱克·麦克斯韦望远镜(JCMT)古尔德带勘测(GBS)是与夏威夷的詹姆士·克莱克·麦克斯韦望远镜一起进行的第一批遗留调查之一，它绘制了附近47°2(<；500pc)的分子云在850和450μm的尘埃连续发射中的图像，以及各种CO同位素谱线上更有限的区域。虽然分子云和形成恒星的物质具有许多尺度的结构，但它们的更大尺度的结构很难在亚毫米范围内使用地面设施可靠地观测到。在本文中，我们量化了JCMT GBS采用的三种后续数据简化方法在多大程度上准确地恢复了不同大小尺度的排放结构，特别是致密岩芯，这是许多GBS科学目标的重点。使用我们目前最好的数据简化程序，我们预计可以100%恢复高斯σ尺寸为≤30“的结构，并且对于孤立的发射峰值，强度峰值至少是本地噪声的五倍。这些紧凑结构的测量尺寸和峰值通量是可靠的(在输入值的15%以内)，但对于较大的发射结构和较暗的峰，源恢复和可靠性都显著降低。在我们的分析中，还没有测试其他因素，如来源拥挤。JCMT GBS最新发布的数据包括指向修正，我们证明这些修正往往会减小我们数据集中致密源的大小并增加峰值强度，主要是在较低的水平(几个百分点)，但偶尔也会有显著的改善。
The James Clerk Maxwell Telescope (JCMT) Gould Belt Survey (GBS) was one of the first legacy surveys with the JCMT in Hawaii, mapping 47 deg2 of nearby (<500 pc) molecular clouds in dust continuum emission at 850 and 450 μm, as well as a more limited area in lines of various CO isotopologues. While molecular clouds and the material that forms stars have structures on many size scales, their larger-scale structures are difficult to observe reliably in the submillimeter regime using ground-based facilities. In this paper, we quantify the extent to which three subsequent data reduction methods employed by the JCMT GBS accurately recover emission structures of various size scales, in particular, dense cores, which are the focus of many GBS science goals. With our current best data reduction procedure, we expect to recover 100% of structures with Gaussian σ sizes of ≤30″ and intensity peaks of at least five times the local noise for isolated peaks of emission. The measured sizes and peak fluxes of these compact structures are reliable (within 15% of the input values), but source recovery and reliability both decrease significantly for larger emission structures and fainter peaks. Additional factors such as source crowding have not been tested in our analysis. The most recent JCMT GBS data release includes pointing corrections, and we demonstrate that these tend to decrease the sizes and increase the peak intensities of compact sources in our data set, mostly at a low level (several percent), but occasionally with notable improvement.