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arXiv · 2205.10263

HI Vertical Structure of Nearby Edge-on Galaxies from CHANG-ES

Yun Zheng·Jing Wang·Judith Irwin·Q. Daniel Wang·Jiangtao Li·Jayanne English·Qingchuan Ma·Ran Wang·Ke Wang·Marita Krause·Toky H. Randriamampandry·Rainer Beck
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Abstract

We study the vertical distribution of the highly inclined galaxies from the Continuum Halos in Nearby Galaxies - an EVLA Survey (CHANG-ES). We explore the feasibility of photometrically deriving the HI disk scale-heights from the moment-0 images of the relatively edge-on galaxies with inclination >80 deg, by quantifying the systematic broadening effects and thus deriving correction equations for direct measurements. The corrected HI disk scale-heights of the relatively edge-on galaxies from the CHANG-ES sample show trends consistent with the quasi-equilibrium model of the vertical structure of gas disks. The procedure provide a convenient way to derive the scale-heights and can easily be applied to statistical samples in the future.

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Yun Zheng, Jing Wang, Judith Irwin, Q. Daniel Wang, Jiangtao Li, Jayanne English, Qingchuan Ma, Ran Wang, Ke Wang, Marita Krause, Toky H. Randriamampandry, Rainer Beck. 2022-05-20. HI Vertical Structure of Nearby Edge-on Galaxies from CHANG-ES. https://doi.org/10.1088/1674-4527%2Fac7389

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