GaussPy+: A fully automated Gaussian decomposition package for emission line spectra

Abstract

Our understanding of the dynamics of the interstellar medium is informed by the study of the detailed velocity structure of emission line observations. One approach to study the velocity structure is to decompose the spectra into individual velocity components; this leads to a description of the dataset that is significantly reduced in complexity. However, this decomposition requires full automation lest it becomes prohibitive for large datasets, such as Galactic plane surveys. We developed GaussPy+, a fully automated Gaussian decomposition package that can be applied to emission line datasets, especially large surveys of HI and isotopologues of CO. We built our package upon the existing GaussPy algorithm and significantly improved its performance for noisy data. New functionalities of GaussPy+ include: i) automated preparatory steps, such as an accurate noise estimation, which can also be used as standalone applications; ii) an improved fitting routine; iii) an automated spatial refitting routine that can add spatial coherence to the decomposition results by refitting spectra based on neighbouring fit solutions. We thoroughly tested the performance of GaussPy+ on synthetic spectra and a test field from the Galactic Ring Survey. We found that GaussPy+ can deal with cases of complex emission and even low to moderate signal-to-noise values.

Accepted for publication in A&A. 36 pages, 33 figures (main text: 23 pages, 18 figures; Appendix: 13 pages, 15 figures). The GaussPy+ package is written in Python 3 and is freely available at GitHub under https://github.com/mriener/gausspyplus

References in corpus (22)

• The NumPy array: a structure for efficient numerical computation
• The Boston University-Five College Radio Astronomy Observatory Galactic Ring Survey
• The VLA Galactic Plane Survey
• Physical properties of molecular clouds for the entire Milky Way disk
• The relation between gas and dust in the Taurus Molecular Cloud
• FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) I: Project Overview and Initial Results
• The Milky Way Imaging Scroll Painting (MWISP): Project Details and Initial Results from the Galactic Longitude of 25.8deg to 49.7deg
• The dynamical properties of dense filaments in the infrared dark cloud G035.39-00.33
• The 21-SPONGE HI Absorption Line Survey II: The temperature of Galactic HI
• The dynamics of collapsing cores and star formation
• 'The Brick' is not a brick: A comprehensive study of the structure and dynamics of the Central Molecular Zone cloud G0.253+0.016
• Turbulence and star formation efficiency in molecular clouds: solenoidal versus compressive motions in Orion B
• Molecular clouds and clumps in the Boston University-Five College Radio Astronomy Observatory Galactic Ring Survey
• The 21-SPONGE HI Absorption Survey I: Techniques and Initial Results
• Autonomous Gaussian Decomposition
• Synthetic C${}^{18}$O observations of fibrous filaments: the problems of mapping from PPV to PPP
• The integrated properties of the molecular clouds from the JCMT CO(3-2) High Resolution Survey
• ROHSA: Regularized Optimization for Hyper-Spectral Analysis - Application to phase separation of 21 cm data
• Droplets I: Pressure-Dominated Sub-0.1 pc Coherent Structures in L1688 and B18
• Molecular filament formation and filament-cloud interaction: Hints from Nobeyama 45m telescope observations
• A dynamically young, gravitationally stable network of filaments in Orion B
• Calibrating the HISA temperature: Measuring the temperature of the Riegel-Crutcher cloud

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