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6.3. Physical conditions of the gas in the center of the nearby spiral galaxy IC 342

Published online by Cambridge University Press:  25 May 2016

J. L. Turner
J. L. Turner*
Affiliation:
Dept. of Physics & Astronomy UCLA, Los Angeles, CA 90095-1562

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One of our nearest neighbors is a large spiral galaxy with abundant molecular gas in its nucleus. IC 342, a face-on Scd galaxy at a distance of 1.8 Mpc, is close enough to give us a view of individual molecular clouds with millimeter interferometry. The CO distribution in the nucleus of IC 342 consists of two very open spiral arms (Lo et al. 1984; Ishizuki et al. 1990) that continue to within 50 pc of the dynamical center (Turner & Hurt 1992). The total extent of the nuclear “mini-spiral” is ~ 500 pc. Corresponding arms are observed in Hα (J.S. Young, private comm.). However, the Hα arms are systematically offset by 50-100 pc from the CO arms (Turner & Hurt 1992). The offset of the Hα arms to the outer, leading edge of the CO arms is consistent with a picture of density wave-induced star formation in the arms (Turner & Hurt 1992). Energy dissipation and angular momentum transfer in spiral arms is believed to drive a slow drift of gas inward; if this is the case, the molecular “mini-spiral” in IC 342 is short-lived, and will probably no longer exist in another 108 years.

Type
Part II. Nuclear Interstellar Medium
Information
Symposium - International Astronomical Union , Volume 184: The Central Regions of the Galaxy and Galaxies , 1998 , pp. 267 - 268
Copyright
Copyright © Kluwer 1998 

References

Downes, D., Radford, S.J.E., Guilloteau, S., Guelin, M., Greve, A., Morris, D. 1992, A&A, 262, 424.Google Scholar
Eckart, A., Downes, D., Genzel, R., Harris, A.I., Jaffe, D.T., Wild, W. 1990, ApJ, 348, 434.CrossRefGoogle Scholar
Ishizuki, S., Kawabe, R., Ishiguro, M., Okumura, S.K., Morita, K.-I., Chikada, Y., Kasuga, T. 1990, Nature, 344, 224.CrossRefGoogle Scholar
Lo, K.Y. et al. 1984, ApJ, 282, 59.CrossRefGoogle Scholar
Martin, R.N., Ho, P.T.P. 1986, 308, L7.Google Scholar
Meier, D., Turner, J.L., Hurt, R.L. 1997, submitted.Google Scholar
Stark, A.A., Bally, J., Wilson, R.W., Pound, M.W. 1989, in The Galactic Center, ed. Morris, M., (Dordrecht: Reidel) 129.CrossRefGoogle Scholar
Turner, J.L., Hurt, R.L., Hudson, D.Y. 1993, ApJ, 413, L19.CrossRefGoogle Scholar
Turner, J.L., Hurt, R.L. 1992, ApJ, 384, 72.CrossRefGoogle Scholar
Wright, M.C.H., Ishizuki, S., Turner, J.L., Ho, P.T.P., Lo, K.Y. 1993, ApJ, 406, 470.CrossRefGoogle Scholar