High Excitation Molecular Gas in the Galactic Center Loops; 12CO(J =2-1 and J =3-2) Observations

  title={High Excitation Molecular Gas in the Galactic Center Loops; 12CO(J =2-1 and J =3-2) Observations},
  author={Natsuko Kudo and Kazufumi Torii and Mami Machida and Timothy A. Davis and Kazuki Tsutsumi and M. Fujishita and Nayuta Moribe and Hiroaki Yamamoto and Takeshi Okuda and Akiko Kawamura and Norikazu Mizuno and Toshikazu Onishi and Hiroyuki Maezawa and Akira Mizuno and Kunihiko Tanaka and Nobuyuki Yamaguchi and Hajime Ezawa and Kunio Takahashi and Satoshi Nozawa and Ryoji Matsumoto and Yasuo Fukui},
  journal={arXiv: Astrophysics of Galaxies},
We have carried out 12CO(J =2-1) and 12CO(J =3-2) observations at spatial resolutions of 1.0-3.8 pc toward the entirety of loops 1 and 2 and part of loop 3 in the Galactic center with NANTEN2 and ASTE. These new results revealed detailed distributions of the molecular gas and the line intensity ratio of the two transitions, R3-2/2-1. In the three loops, R3-2/2-1 is in a range from 0.1 to 2.5 with a peak at ~ 0.7 while that in the disk molecular gas is in a range from 0.1 to 1.2 with a peak at 0… 
12CO and 13CO J = 3–2 observations toward N11 in the Large Magellanic Cloud
Aims. After 30 Doradus, N11 is the second largest and brightest nebula in the Large Magellanic Cloud (LMC). This large nebula has several OB associations with bright nebulae at its surroundings. N11
Discovery of possible molecular counterparts to the infrared Double Helix Nebula in the galactic center
We have discovered two molecular features at radial velocities of ?35?km?s?1 and 0?km?s?1 toward the infrared Double Helix Nebula (DHN) in the Galactic center with NANTEN2. The two features show good
Processing of Polycyclic Aromatic Hydrocarbons in Molecular-Loop Regions near the Galactic Center Revealed by AKARI
We present the AKARI mid-infrared diffuse map of an area of about 4 deg x 3 deg near the Galactic center in the 9 um band. The band intensity is mostly attributed to the aromatic hydrocarbon infrared
Kinetic temperatures toward X1/X2 orbit interceptions regions and giant molecular loops in the Galactic center region
Context. It is well known that the kinetic temperatures, Tkin, of the molecular clouds in the Galactic center region are higher than in typical disk clouds. However, the Tkin of the molecular
Discovery of a Giant Molecular Loop in the Central Region of NGC 253
NGC 253 is a starburst galaxy of SAB(s)c type with increasing interest because of its high activity at unrivaled closeness. Its energetic event is manifested as the vertical gas features in its
Cloud–cloud collisions in the common foot point of molecular loops 1 and 2 in the Galactic Center
Recent large-area, deep CO surveys in the Galactic disk have revealed the formation of ~50 high-mass stars or clusters triggered by cloud–cloud collisions (CCCs). Although the Galactic Center
The Double Helix Nebula (DHN), located 100 pc above Sgr A* in the Galactic center (GC), is a unique structure whose morphology suggests it is a magnetic feature. Recent molecular observations toward
Using CO line ratios to trace compressed areas in bubble N131
Aims. N131 is a typical infrared dust bubble showing an expanding ring-like shell. We study the CO line ratios that can be used to trace the interaction in the expanding bubble. Methods. We carried
Formation of Galactic Prominence in the Galactic Central Region
We carried out 2.5-dimensional resistive MHD simulations to study the formation mechanism of molecular loops observed by Fukui et al. in the Galactic central region. Since it is hard to form
Hidden Star Formation in High-Velocity Gas Clouds in Clump 2 near the Edge of the CMZ
  • V. Tolls, H. Smith
  • Physics, Environmental Science
    Proceedings of the International Astronomical Union
  • 2016
Abstract We present a snapshot of our ongoing investigation of molecular clouds in Clump 2 located in the Galactic Bar region at a projected distance of ~400pc from the Galactic Center. We show that


Temperature and Density in the Foot Points of the Molecular Loops in the Galactic Center; Analysis of Multi-J Transitions of 12CO(J=1-0, 3-2, 4-3, 7-6), 13CO(J=1-0) and C18O(J=1-0)
Fukui et al. (2006) discovered two molecular loops in the Galactic center and argued that the foot points of the molecular loops, two bright spots at both loops ends, represent the gas accumulated by
A Detailed Observational Study of Molecular Loops 1 and 2 in the Galactic Center
Fukui et al. (2006) discovered two molecular loops in the Galactic center that are likely created by the magnetic flotation due to the Parker instability with an estimated field strength of ∼150 µG.
Discovery of Molecular Loop 3 in the Galactic Center: Evidence for a Positive-Velocity Magnetically Floated Loop towards L = 355°-359°
We have discovered a molecular dome-like feature towards 355 il � 359 i and 0 ib � 2 i . The large velocity dispersions of 50-100 km s � 1 of this feature are much larger than those in the Galactic
Carbon monoxide in the inner galaxy
Emission from the J=1..-->..0 rotational transition of /sup 12/C/sup 16/O has been surveyed at b=0/sup 0/ in the region 10/sup 0/> or =l> or =352/sup 0/ with high angular (..delta..l=0/sup 0/.2,
Clump 1 - An unusual molecular cloud complex near the Galactic center
The properties of the (C-12)O and (C-13)O emission from Clump I, a complex of molecular clouds which shows the largest noncircular velocities of any molecular material known in the Milky Way, are
Disk-Halo interface: The "foot point" of the Galactic Molecular Loops
We study the disk-halo interaction, in the context of orbits and Giant Molecular loops (GMLs) in the Galactic center (GC) region. We present a large scale survey in the central kpc in SiO(J=2-1),
Molecular cooling and thermal balance of dense interstellar clouds
We analyze in detail the cooling produced by line emission from a variety of molecular and atomic species, including those observed as well as theoretically expected in dense interstellar clouds. At
Similarity between the Molecular Loops in the Galactic Center and the Solar Chromospheric Arch Filaments
We carried out two-dimensional magnetohydrodynamic simulations of the Galactic gas disk to show that the dense loop-like structures discovered by the Galactic center molecular cloud survey by NANTEN
Tracing gas accretion in the Galactic center using isotopic ratios
Aims. We study the 12 C/ 13 C isotopic ratio in the disk of the central molecular zone and in the halo to trace gas accretion toward the Galactic center region in the Milky Way. Methods. Using the
Evidence of a Weak Galactic Center Magnetic Field from Diffuse Low-Frequency Nonthermal Radio Emission
New low-frequency 74 and 330 MHz observations of the Galactic center (GC) region reveal the presence of a large-scale (6° × 2°) diffuse source of nonthermal synchrotron emission. A minimum-energy