ALMA view of the circumnuclear disk of the Galactic Center: tidally disrupted molecular clouds falling to the Galactic Center
| العنوان: | ALMA view of the circumnuclear disk of the Galactic Center: tidally disrupted molecular clouds falling to the Galactic Center |
|---|---|
| المؤلفون: | Kenta Uehara, Makoto Miyoshi, Takahiro Tsutsumi, Ryosuke Miyawaki, Yoshimi Kitamura, Masato Tsuboi, Atsushi Miyazaki |
| المصدر: | Publications of the Astronomical Society of Japan. 70 |
| بيانات النشر: | Oxford University Press (OUP), 2018. |
| سنة النشر: | 2018 |
| مصطلحات موضوعية: | Physics, stars: formation, Galaxy: center, 010308 nuclear & particles physics, Molecular cloud, Galactic Center, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, accretion: accretion disks, 01 natural sciences, ISM: molecules, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Falling (sensation), 010303 astronomy & astrophysics |
| الوصف: | We present the high angular resolution and high sensitivity images of the "Circum-Nuclear Disk (CND)" and its surrounding region of Milky Way Galaxy in the CS J=2-1, SiO v=0 J=2-1, H^13CO^+ J=1-0, C^34S J=2-1, and CH_3OH J_{K_a, K_c}=2_{1,1}-1_{1,0}A_{--} emission lines using ALMA. The CND is recognized as a torus-like molecular gas with gaps in these emission lines except for the CH_3OH emission line. The inner and outer radii of the CND are estimated to be R_in~1.5 and R_out~2 pc, respectively. The velocities of the rotation and radial motion are estimated to be V_rot~115 km s^-1 and V_rad~23 km s^-1, respectively. The LTE molecular gas mass is estimated to be M_LTE~3x10^4 Mo. We also found some anomalous molecular clouds in the surrounding region. One of the molecular clouds is positionally connected to a part of the CND adjacent to the "Western Arc". However, the cloud is seen to rotate in the opposite direction to the CND. The molecular cloud would be falling currently from the outer region to the CND and being disrupted by the tidal shear of Sagittarius A*(Sgr A*) because the velocity is not yet assimilated into that of the CND. Another molecular cloud is continuously connected to the tip of the "Eastern Arm (EA)". The velocity of this cloud is consistent with that of the ionized gas in the EA. These facts suggest that the molecular cloud is falling from the outer region to the vicinity of Sgr A*, being disrupted by the tidal shear, and ionized by strong UV emission from the Central Cluster because the impact parameter of the cloud is smaller than the first cloud. These falling clouds would play an important role in transferring material from the outer region to the CND and/or the vicinity of Sgr A*. Comment: 31 pages, 12 figures, Accepted for publication in PASJ |
| تدمد: | 2053-051X 0004-6264 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9fdefbf3196b4364e2447d87f90d14b4 https://doi.org/10.1093/pasj/psy080 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....9fdefbf3196b4364e2447d87f90d14b4 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 2053051X 00046264 |
|---|