Physical properties of dense molecular gas in centres of Seyfert galaxies

A wealth of data is now available on the energetic mass outflows that are associated with young stellar objects. This phenomenon is thought to occur at a very early stage in the evolution of stars of almost all masses. The discovery of this energetic event was first made through observations of the rapidly expanding molecular gas that surrounds many of these young stellar objects. A review of the physical properties, including the energetics and morphology, of the expanding molecular gas is presented in this paper. In addition, the role these energetic winds play in affecting the dynamics of the parental molecular clouds is also discussed. Finally, the results of detailed studies of the structure and kinematics of the high velocity molecular gas are reviewed and the evidence for existance of wind-swept cavities and molecular shells within the clouds are presented.

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Recovering the Physical Properties of Molecular Gas in Galaxies from CO SLED Modeling

The Astrophysical Journal ◽

10.3847/1538-4357/aab3e2 ◽

2018 ◽

Vol 859 (1) ◽

pp. 9 ◽

Cited By ~ 6

Author(s):

J. Kamenetzky ◽

G. C. Privon ◽

D. Narayanan

Keyword(s):

Physical Properties ◽

Molecular Gas

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The Structure, Kinematics, and Physical Properties of the Molecular Gas in the Starburst Nucleus of NGC 253

The Astrophysical Journal ◽

10.1086/422354 ◽

2004 ◽

Vol 611 (2) ◽

pp. 835-845 ◽

Cited By ~ 27

Author(s):

Timothy A. D. Paglione ◽

Omar Yam ◽

Tomoka Tosaki ◽

James M. Jackson

Keyword(s):

Physical Properties ◽

Molecular Gas

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Dense molecular gas in Seyfert galaxies

Astronomy and Astrophysics Supplement Series ◽

10.1051/aas:2000119 ◽

2000 ◽

Vol 141 (2) ◽

pp. 193-209 ◽

Cited By ~ 37

Author(s):

S. J. Curran ◽

S. Aalto ◽

R. S. Booth

Keyword(s):

Seyfert Galaxies ◽

Molecular Gas

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CO Observations of High-z Objects

Symposium - International Astronomical Union ◽

10.1017/s0074180900132395 ◽

1999 ◽

Vol 183 ◽

pp. 159-159

Author(s):

K. Ohta ◽

K. Nakanishi ◽

M. Akiyama ◽

T.T. Takeuchi ◽

T. Yamada ◽

...

Keyword(s):

Physical Properties ◽

Line Width ◽

Conversion Factor ◽

Line Ratio ◽

Molecular Gas ◽

Nearby Star ◽

Gas Density ◽

Upper Limit ◽

The Mean ◽

Co Observations

We have made a CO (J=2−1) observation using the Nobeyama 45m telescope aimed at examining physical properties of the molecular gas in the object. Upper limit obtained is 1.8 mK (3σ) at a velocity resolution of 100 km s−1, which leads to an upper limit on the molecular gas mass of 5.3 × 1011M⊙, if we assume a line width of 250 km s−1 obtained in J = 5–4 line and the Galactic CO-to-H2 conversion factor of 4.5 M⊙ K km s−1 pc2. The line ratio between 2–1 line and 5–4 line as well as those from 7–6 and 4–3 lines (Omont et al. 1996) imply that the mean gas density is as high as 103–5 cm−3, which is comparable to that in nearby star burst galaxies (e.g., Solomon et al. 1992).

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Physical properties and kinematics of the molecular gas near galaxy nuclei

Symposium - International Astronomical Union ◽

10.1017/s0074180900009645 ◽

1997 ◽

Vol 178 ◽

pp. 489-500

Author(s):

L.J. Tacconi

Keyword(s):

Physical Properties ◽

Spatial Resolution ◽

Chemical Processes ◽

Molecular Gas ◽

Submillimeter Wavelength ◽

Nearby Galaxies ◽

Physical And Chemical ◽

Size Scales ◽

Made In ◽

Gas Properties

During the last decade there have been enormous steps forward in our understanding of the molecular gas properties of other galaxies, due to the huge increase in sensitivity and spatial resolution of instruments in the millimeter and submillimeter wavelength ranges. In particular, the emphasis has shifted from trying to detect CO in a variety of objects to studying the gas distributions and kinematics in a variety of species and transitions. For nearby galaxies, we are now able to study the physical and chemical processes occurring in the molecular gas over GMC size scales. Here I discuss a few examples of progress made in the study of galaxy nuclei.

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First Galaxies and AGNs

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306010155 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 358-361

Author(s):

Fabian Walter

Keyword(s):

Black Hole ◽

Physical Properties ◽

Molecular Gas ◽

Host Galaxies ◽

First Galaxies ◽

Dynamical Masses

AbstractI will discuss the search for galaxies and QSOs at the highest redshifts, out to the Epoch of Reionization. Observations in the submillimeter play a fundamental role in such searches, in particular once ALMA will become operational. I will focus on the properties of the molecular gas (the phase of the ISM out of which stars form) in the earliest systems as derived through observations in the millimetre and radio regime. These observations allow us to measure the reservoir of molecular gas and to constrain the physical properties and excitation of the gas. Resolved imaging of the host galaxies also allows us to derive first dynamical masses for these objects. Such mass determinations are critical to determine whether there is a possible evolution of the famous MBH–σbulgerelation with redshift or not. Recent measurements in the QSO redshift record holder J1148+5251 (z= 6.42) provide evidence that the black hole in this system assembled before the stellar bulge.

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