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arXiv · 2208.04581

FERIA: Flat Envelope Model with Rotation and Infall under Angular Momentum Conservation

Yoko Oya·Hirofumi Kibukawa·Shota Miyake·Satoshi Yamamoto
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Abstract

Radio observations of low-mass star formation in molecular spectral lines have rapidly progressed since the advent of Atacama Large Millimeter/submillimeter Array (ALMA). A gas distribution and its kinematics within a few 100s au scale around a Class 0-I protostar are spatially resolved, and the region where a protostellar disk is being formed is now revealed in detail. In such studies, it is essential to characterize the complex physical structure around a protostar consisting of an infalling envelope, a rotationally-supported disk, and an outflow. For this purpose, we have developed a general-purpose computer code `{\tt FERIA}' (Flat Envelope model with Rotation and Infall under Angular momentum conservation) generating the image cube data based on the infalling-rotating envelope model and the Keplerian disk model, both of which are often used in observational studies. In this paper, we present the description and the usage manual of {\tt FERIA} and summarize caveats in actual applications. This program outputs cube {\tt FITS} files, which can be used for direct comparison with observations. It can also be used to generate mock data for the machine/deep learnings. Examples of these applications are described and discussed to demonstrate how the model analyses work with actual observational data.

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Yoko Oya, Hirofumi Kibukawa, Shota Miyake, Satoshi Yamamoto. 2022-08-09. FERIA: Flat Envelope Model with Rotation and Infall under Angular Momentum Conservation. https://doi.org/10.1088/1538-3873%2Fac8839

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