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The Formation of Stellar Galactic Nuclei through Dissipative Gas Dynamics

Published online by Cambridge University Press:  05 March 2013

K. Bekki
K. Bekki*
Affiliation:
School of Physics, University of New South Wales, Sydney 2052, Australia. Email: [email protected]
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Abstract

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It is a long-standing and remarkable problem as to howstellar galactic nuclei (SGN) were formed in the central region of galaxies. In order to elucidate the formation processes of SGN, we numerically investigate gas dynamics, star formation, and chemical evolution in the central 1–1000 pc of gas disks embedded by galactic stellar spheroids. The main results of the present numerical study are: (a) SGN can be formed from dissipative, repeated merging of massive stellar and gaseous clumps that have typical masses of 105–106 M⊙ and are developed from nuclear gaseous spiral arms owing to local gravitational instability. Typically ∼5% of the masses of their host spheroids can be transfered to the central∼50 pc and thus become SGN. (b) SGN have very flattened shapes, and rotational kinematics and central velocity dispersions much smaller than those of their host spheroids. These structural and kinematic characteristics do not depend on model parameters such as masses of spheroids (Msph) and initial gas mass fraction (fg). (c) Stellar populations of SGN can show a wide rage of ages and metallicities, because SGN are formed from massive clumps with different star-formation and chemical-evolution histories. The mean metallicities of SGN can be significantly higher than those of their host spheroids. (d) More massive, higher density SGN can be formed in spheroids with higher surface brightness. Furthermore there can be a threshold value (∼0.2) of fg below which massive SGN are less likely to be formed in the central gas disks of spheroids. (e) More massive spheroids can have more massive, more metal-rich and higher-density SGN, because star formation and chemical enrichment proceed more efficiently owing to the less dramatic suppression of star formation by supernovae feedback effects in more massive spheroids.

Based on these results, we discuss correlations between the physical properties of SGN and those of their host galaxies, structural and kinematic properties of SGN of dwarf elliptical galaxies and the origin of very massive star clusters such as ω Cen and ultra-compact dwarf galaxies.

Keywords

galaxies: nucleigalaxies: irregulargalaxies: starburstgalaxies: star clustersgalaxies: structure
Type
Research Article
Information
Publications of the Astronomical Society of Australia , Volume 24 , Issue 2 , 2007 , pp. 77 - 94
Copyright
Copyright © Astronomical Society of Australia 2007

References

Andredakis, Y. C. & Sanders, R. H., 1994, MNRAS, 267, 283 Google Scholar
Balcells, M., Graham, A. W., Domínguez-Palmero, L. & Peletier, R. F., 2003, ApJ, 582, 79 CrossRefGoogle Scholar
Bekki, K. & Shioya, Y., 1998, ApJ, 497, 108 CrossRefGoogle Scholar
Bekki, K. & Shioya, Y., 1999, ApJ, 513, 108 Google Scholar
Bekki, K. & Freeman, K. C., 2003, MNRAS, 346, L11 CrossRefGoogle Scholar
Bekki, K., Couch, W. J. & Drinkwater, M. J., 2001, ApJ, 552, L105 Google Scholar
Bekki, K., Couch, W. J., Drinkwater, M. J. & Shioya, Y., 2003, MNRAS, 344, 399 CrossRefGoogle Scholar
Bekki, K., Couch, W. J., Drinkwater, M. J. & Shioya, Y. 2004, ApJ, 610, L13 CrossRefGoogle Scholar
Bekki, K. & Chiba, M., 2004, A&A, 417, 437 Google Scholar
Bekki, K. & Norris, J. E., 2006, ApJL, 637, 109 CrossRefGoogle Scholar
Bekki, K., Couch, W. J. & Shioya, Y., 2006, ApJL, 642, 133 Google Scholar
Bekki, K., Shioya, Y. & Whiting, M., 2006, MNRAS, 371, 805 Google Scholar
Binggeli, B. & Cameron, L. M., 1991, A&A, 252, 27 Google Scholar
Binney, J. & Tremaine, S., 1987, Galactic Dynamics (Princeton, NJ: Princeton University Press)Google Scholar
Binney, J. & Merrifield, M., 1998, Galactic Astronomy (Princeton, NJ: Princeton University Press)Google Scholar
Böker, T., Laine, S., van der Marel, R. P., Sarzi, M., Rix, H.-W., Ho, L. C. & Shields, J. C., 2002, AJ, 123, 1389 Google Scholar
Böker, T., Sarzi, M., McLaughlin, D. E., van der Marel, R. P., Rix, H.-W., Ho, L. C. & Shields, J. C., 2004, AJ, 127, 105 CrossRefGoogle Scholar
Bothun, G. D. & Mould, J. R., 1988, ApJ, 324, 123 Google Scholar
Caldwell, N. & Bothun, G. D., 1987, 94, 1126 Google Scholar
Carollo, C. M., Stiavelli, M. & Mack, J., 1998, AJ, 116, 68 Google Scholar
Combes, F. & Gerin, M., 1985, A&A, 150, 327 Google Scholar
Côte, P., Marzke, R. O., West, M. J. & Minniti, D., 2000, ApJ, 533, 869 Google Scholar
Côte, P. et al., 2006, ApJS, 165, 57 CrossRefGoogle Scholar
Davies, R. L., Burstein, D., Dressler, A., Faber, S. M., Lynden-Bell, D., Terlevich, R. J. & Wegner, G., 1987, ApJS, 64, 581 CrossRefGoogle Scholar
Dekel, A. & Silk, J., 1986, ApJ, 303, 39 Google Scholar
De Propris, R., Philipps, S., Drinkwater, M. J., Gregg, M. D., Jones, J. B., Evstigneeva, E. & Bekki, K., 2005, ApJL, 623, 105 Google Scholar
Dinescu, D. I., Girard, T. M. & van Altena, W. F., 1999, AJ, 117, 1792 CrossRefGoogle Scholar
Djorgovski, S. G., Gal, R. R., McCarthy, J. K., Cohen, J. G., de Carvalho, R. R., Meylan, G., Bendinelli, O. & Parmeggiani, G., 1997 ApJ, 474, L19 Google Scholar
Drinkwater, M. J., Jones, J. B., Gregg, M. D. & Philipps, S. 2000, PASA, 17, 227 CrossRefGoogle Scholar
Drinkwater, M. J., Gregg, M. D., Hilker, M., Bekki, K., Couch, W. J., Ferguson, J. B., Jones, J. B. & Philipps, S., 2003, Nature, 423, 519 Google Scholar
Drinkwater, M. J. et al., 2005, submitted to AJGoogle Scholar
Elmegreen, B. G., 2002, Ap&SS, 284, 819 Google Scholar
Fellhauer, M. & Kroupa, P., 2002, Ap&SS, 281, 355 Google Scholar
Ferguson, H. C. & Bingelli, B., 1994, A&ARv, 6, 67 Google Scholar
Ferraro, F. R., Bellazzini, M. & Pancino, E., 2002, ApJL, 573, 95 Google Scholar
Freeman, K. C. & Rodgers, A. W., 1975, ApJ, 201, 71 Google Scholar
Freeman, K. C. 1993, in ASPC 48, The Globular Clusters–Galaxy Connection, Eds. Smith, G. H. & Brodie, J. P. (San Francisco: Astronomical Society of the Pacific), 48, 608 Google Scholar
Geha, M., Guhathakurta, P. & van der Marel, R. P., 2002, AJ, 124, 3073 Google Scholar
Graham, A. W., Jerjen, H. & Guzmán, R., 2003, AJ, 126, 1787 Google Scholar
Graham, A. W. & Guzmán, R., 2003, AJ, 125, 2936 Google Scholar
Gregg, M. D. et al. 2007, submitted to AJGoogle Scholar
Hausman, M. A. & Roberts, W. W. Jr., 1984, ApJ, 282, 106 Google Scholar
Hilker, M. & Richtler, T., 2000, A&A, 362, 895 Google Scholar
Ichikawa, S. I., Wakamatsu, K. I. & Okamura, S., 1986, ApJS, 60, 475 Google Scholar
Jerjen, H., Kalnajs, A. & Binggeli, B., 2000, A&A, 358, 845 Google Scholar
Jones, J. B. et al., 2006, AJ, 131, 312 CrossRefGoogle Scholar
Kauffmann, G. et al., 2003, MNRAS, 341, 54 Google Scholar
Kennicutt, R. C. Jr., 1998, ARA&A, 36, 189 Google Scholar
Lambas, D. G., Maddox, S. J. & Loveday, J. 1992, MNRAS, 258, 404 Google Scholar
Larson, R. B., 1981, MNRAS, 194, 809 Google Scholar
Larson, R. B., 1998, MNRAS, 301, 569 Google Scholar
Lee, Y.-W., Joo, J.-M., Sohn, Y.-J., Rey, S.-C., Lee, H.-C. & Walker, A. R., 1999, Natur, 402, 55 Google Scholar
Lotz, J. M., Miller, B. W. & Ferguson, H. C., 2004, ApJ, 613, 262 Google Scholar
Magorrian, J. T. et al., 1998, AJ, 115, 2285 Google Scholar
Makino, J., Akiyama, K. & Sugimoto, D., 1991, Ap&SS, 185, 63 Google Scholar
Mateo, M., 1998, ARAA, 36, 435 Google Scholar
Matthews, L. D. et al., 1999, AJ, 118, 208 CrossRefGoogle Scholar
Meylan, G., 1987, A&A, 184, 144 Google Scholar
Mieske, S., Hilker, M. & Infante, L., 2004, A&A, 418, 445 Google Scholar
Milosavljević, M., 2004, ApJ, 605, L13 CrossRefGoogle Scholar
Mould, J. R., 1984, PASP, 96, 773 Google Scholar
Noguchi, M. 1991, IAUS, 146, 343 Google Scholar
Norris, J. E., Freeman, K. C. & Mighell, K. J., 1996, ApJ, 462, 241 Google Scholar
Norris, J. E., Freeman, K. C., Mayor, M. & Seitzer, P., 1997, ApJ, 487, L187Google Scholar
Norris, J. E. & Da Costa, G. S., 1995, ApJ, 447, 680 Google Scholar
Oh, K. S. & Lin, D. N. C., 2000, ApJ, 543, 620 Google Scholar
Pancino, E., Ferraro, F. R., Bellazzini, M., Piotto, G. & Zoccali, M., 2000, ApJL, 534, 83 Google Scholar
Philips, S., Drinkwater, M. J., Gregg, M. D. & Jones, J. B., 2001, ApJ, 560, 201 Google Scholar
Phillips, A. C., Illingworth, G. D., MacKenty, J. W. & Franx, M. 1996, AJ, 111, 1566 CrossRefGoogle Scholar
Seth, A. C., Dalcanton, J. J., Hodge, P. W. & Debattista, V. P., 2006, AJ, 132, 2539 CrossRefGoogle Scholar
Schmidt, M., 1959, ApJ, 129, 243 Google Scholar
Smith, V. V., Suntzeff, N. B., Cunha, K., Gallino, R., Busso, M., Lambert, D. L. & Straniero, O., 2000, AJ, 119, 1239 Google Scholar
Stiavelli, M., Miller, B. W., Ferguson, H. C., Mack, J., Whitmore, B. C. & Lotz, J. M., 2001, AJ, 121, 1385 Google Scholar
Sugimoto, D., Chikada, Y., Makino, J., Ito, T., Ebisuzaki, T. &Google Scholar
Umemura, M., 1990, Natur, 345, 33 Google Scholar
Tacconi, L. J. & Young, J. S., 1986, ApJ, 308, 600 Google Scholar
Thornton, K., Gaudlitz, M., Janka, H.-Th. & Steinmetz, M., 1998, ApJ, 500, 95 Google Scholar
Tremaine, S. D., Ostriker, J. P. & Spitzer, L. Jr., 1975, ApJ, 196, 407 CrossRefGoogle Scholar
van den Bergh, S., AJ, 1986, 91, 271 CrossRefGoogle Scholar
Vazdekis, A., Casuso, E., Peletier, R. F. & Beckman, J. E., 1996, ApJS, 106, 307 Google Scholar
Villanova, S. et al., 2007, ApJ, 663, 296 Google Scholar
Walcher, C. J. et al., 2005, ApJ, 618, 237 Google Scholar
Zinnecker, H., Keable, C. J., Dunlop, J. S., Cannon, R. D. & Griffiths, W. K., 1988, in Globular Cluster Systems in Galaxies, Eds. Grindlay, J. E. & Davis Philip, A. G. (Dordrecht, Kluwer), 603 Google Scholar