Title: | CO Multi-line Imaging of Nearby Galaxies (COMING). III. Dynamical effect on molecular gas density and star formation in the barred spiral galaxy NGC 4303 |
Authors: | Yashima, Yoshiyuki Browse this author |
Kajikawa, Ayumi Browse this author |
Komatsuzaki, Ryusei Browse this author |
Kita, Shoichiro Browse this author |
Watanabe, Yoshimasa Browse this author |
Seta, Masumichi Browse this author |
Shibata, Shugo Browse this author |
Oi, Nagisa Browse this author |
Yasuda, Atsushi Browse this author |
Kuroda, Mayu Browse this author |
Yoda, Moe Browse this author |
Takeuchi, Tsutomu T Browse this author |
Noma, Yuto Browse this author |
Pan, Hsi-An Browse this author |
Matsumoto, Naoko Browse this author |
Morokuma-Matsui, Kana Browse this author |
Salak, Dragan Browse this author |
Sato, Yuya Browse this author |
Tanaka, Takahiro Browse this author |
Nakai, Naomasa Browse this author |
Nakanishi, Hiroyuki Browse this author |
Kaneko, Hiroyuki Browse this author |
Miyamoto, Yusuke Browse this author |
Muraoka, Kazuyuki Browse this author |
Kuno, Nario Browse this author |
Sorai, Kazuo Browse this author |
Yajima, Yoshiyuki Browse this author |
Keywords: | galaxies: individual (NGC 4303) |
galaxies: ISM |
galaxies: spiral |
galaxies: star formation |
radio lines: galaxies |
Issue Date: | Dec-2019 |
Publisher: | Oxford University press |
Journal Title: | Publications of the Astronomical Society of Japan |
Volume: | 71 |
Issue: | Supplement_1 |
Start Page: | S13 |
Publisher DOI: | 10.1093/pasj/psz022 |
Abstract: | We present the results of 12CO(J = 1–0) and 13CO(J = 1–0) simultaneous mappings toward the nearby barred spiral galaxy NGC4303 as part of the CO Multi-line Imaging of Nearby Galaxies (COMING) project. Barred spiral galaxies often show lower starformation efficiency (SFE) in their bar region compared to the spiral arms. In this paper, we examine the relation between the SFEs and the volume densities of molecular gas n(H2) in the eight different regions within the galactic disk with CO data combined with archival far-ultraviolet and 24 μm data. We confirmed that SFE in the bar region is lower by 39% than that in the spiral arms. Moreover, velocity-alignment stacking analysis was performed for the spectra in the individual regions. Integrated intensity ratios of 12CO to 13CO (R12/13) ranging from 10 to 17 were the results of this stacking. Fixing a kinetic temperature ofmolecular gas, n(H2)was derived from R12/13 via non-local thermodynamic equilibrium (non-LTE) analysis. The density n(H2) in the bar is lower by 31%–37% than that in the arms and there is a rather tight positive correlation between SFEs and n(H2), with a correlation coefficient of ∼0.8. Furthermore, we found a dependence of n(H2) on the velocity dispersion of inter-molecular clouds (ΔV/sin i). Specifically, n(H2) increases as ΔV/sin i increases when ΔV/sin i < 100kms−1. On the other hand, n(H2) decreases as ΔV/sin i increases whenΔV/sin i>100kms−1. These relations indicate that the variations of SFE could be caused by the volume densities of molecular gas, and the volume densities could be governed by the dynamical influence such as cloud–cloud collisions, shear, and enhanced inner-cloud turbulence. |
Rights: | This is a pre-copyedited, author-produced version of an article accepted for publication in Publications of the Astronomical Society of Japan following peer review. The version of record CO Multi-line Imaging of Nearby Galaxies (COMING). III. is available online at: https://doi.org/10.1093/pasj/psz022. |
Type: | article (author version) |
URI: | http://hdl.handle.net/2115/82097 |
Appears in Collections: | 理学院・理学研究院 (Graduate School of Science / Faculty of Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|