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arXiv · 2110.11620

Molecular Clump Extraction Algorithm Based on Local Density Clustering

Xiaoyu Luo·Sheng Zheng·Yao Huang·Shuguang Zeng·Xiangyun Zeng·Zhibo Jiang·Zhiwei Chen
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Abstract

The detection and parametrization of molecular clumps is the first step in studying them. We propose a method based on Local Density Clustering algorithm while physical parameters of those clumps are measured using the Multiple Gaussian Model algorithm. One advantage of applying the Local Density Clustering to the clump detection and segmentation, is the high accuracy under different signal-to-noise levels. The Multiple Gaussian Model is able to deal with overlapping clumps whose parameters can be derived reliably. Using simulation and synthetic data, we have verified that the proposed algorithm could characterize the morphology and flux of molecular clumps accurately. The total flux recovery rate in $^{13}\rm CO$ (J=1-0) line of M16 is measured as 90.2\%. The detection rate and the completeness limit are 81.7\% and 20 K km s$ ^{-1} $ in $^{13}\rm CO$ (J=1-0) line of M16, respectively.

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Xiaoyu Luo, Sheng Zheng, Yao Huang, Shuguang Zeng, Xiangyun Zeng, Zhibo Jiang, Zhiwei Chen. 2021-10-22. Molecular Clump Extraction Algorithm Based on Local Density Clustering. https://doi.org/10.1088/1674-4527%2Fac321d

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