Publication: Star formation in the nucleus of the galaxy NGC-5253
Loading...
Official URL
Full text at PDC
Publication Date
1987-11
Authors
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
EDP Sciencies
Abstract
Summary. Optical and ultraviolet spectroscopic observations of the nucleus of the galaxy NGC5253 are analyzed. This galaxy presents the typical features of an elliptical system at large distances from its center. However, its nucleus is dominated by an emission complex composed by severa) giant H rr regions. The analysis of the optical spectra shows that the metallic abundances in the nucleus of the galaxy are below the solar values. The presence of O stars can be deduced from the numerous absorption Iines present in the UV spectrum. The UV emission lines indicate a high effective temperature for the ionizing star cluster. The comparison of the observations with evolutive models of W(Hp) and the slope of the UV continuum shows that the age of the brightest knot of the nucleus of NGC 5253 is less than three millions years. The exact age depends on the choice of the extinction law, not well known in this type of objects. An LMC like law (consistent with the low metallicity of the object) leads to an age of 2.3 106 yr, and to an IMF similar or slightly flatter than that found by Salpeter for the solar neighbourhood, with an upper mass limit in the range 60 M 0 < M0P < 120 M 0 .
Description
© European Southern Observatory. Acknowledgements. We wish to thank Dr. W. Wamsteker for providing us with the IPCS observations of NGC 5253, and for his useful remarks on the original manuscript.
UCM subjects
Unesco subjects
Keywords
Citation
Aitken , D.K., Roche, P. F., Phillips, M. M.: 1982, Monthly Notices Roy. Astron. Soc. 199, 31
Alcock , C., Paczyúski, B.: 1978, Astrophys . J. 223, 244 Brocklehurst , M.: 1971, Monthly Notices
Roy. Astron . Soc. 153,
471
Brocklehurst , M.: 1972, Monthly Notices Roy. Astron . Soc. 157, 211
Bohuski, T.J., Burbidge, E.M., Burbidge, G.R., Smith, M.G.: 1972, Astrophys. J. 175, 329
Boksenberg, A.: 1972, in ESO Workshop on Two Dimensional Photometry , p. 295
Bottinelli, L., Gouguenheim , L., Heidmann, J.: 1972, Astron .
Astrophys. 17, 445
Bruzual, G.: 1983, Astrophys. J: 273, 105
Burbidge, E. M., Burbidge, G.R.: 1962, Astrophys . J. 135, 696 Burstein, D., Heiles, C.: 1984,
Astrophys. J. Suppl. 54, 33 Campbell, A., Terlevich, R.: 1984, Monthly Notices Roy . Astron .
Soc. 211, 15
Cassatella, A., Barbero, J ., Benvenuti , P.: 1985, Astron. Astro phys. 144, 335
De Vaucouleurs, G., de Vaucouleurs , A., Corwin, H.G.: 1976, "Second Reference Catalog of Bright
Galaxies", Univ. of Texas Press
Durret, F., Bergeron , J., Boksemberg , A.: 1985, Astron. Astro- phys. 143, 347
Evans, D.: 1952, The Observatory 869, 164
Gaposhkin, C.: 1936, Astrophys. J. 83, 173
Heck, A., Egret, D., Jascheck, M., Jascheck , C.: 1984, "IUE Low Dispersion Spectra Reference
Atlas. Part 1: Normal Stars", ESA SP-1052
Holm, A., Bohlin, R.C., Cassatella, A., Ponz, D.P., Schiffer, F.H.: 1982, Astron . Astrophys . 122,
341
Hubble, E., Lundmark , K.: 1923, Pub!. Astron. Soc. Pacific 34, 292
Huchra, J. P. et al.: 1983, Astrophys . J. 274, 125 Hunter, D.: 1982, Astrophys . J. 260, 81
Hunter, D., Gallagher, J., Rauntenkranz , D.: 1982, Astrophys. J. Suppl. 49, 53
Kurucz, R.: 1979, Astrophys. J. Suppl. 40, 1
Lamb, S., Gallagher, J .S., Hjellming, M.S., Hunter, D.A.: 1984,
Astrophys. J. 291, 63
Lequeux, J .: 1980, in Star Formation, eds. A. Maeder, L.Martinet , Geneva Observatory, Sauverny,
p. 35
Lequeux , J., Maucherat-Joubert, M., Deharveng, J.M., Kunth, D.: 1981, Astron . Astrophys. 103, 305
Lewis, B., Davis, R.: 1973, M onthly Notices Roy. Astron. Soc. 165, 213
Maeder , A.: 1980, Astron. Astrophys. 92, 101 Maeder, A.: 1981a, Astron. Astrophys. 99, 97
Maeder, A.: 1981b, Astron. Astrophys . 102, 401
Maeder , A.: 1983, Astron . Astrophys. 120, 113
Melnick, J ., Televich , R., Eggleton, P.P.: 1985, M onthly Notices Roy. Astron. Soc. 216, 255
Mengel , J.G., Sweigart, A.V., Demarque, P., Gross, P.G.: 1979,
Astrophys. J. Suppl. 40, 733
Middelburg, F., Crarie, P.: 1979, in lmage Processing in Astro nomy, eds. G. Sedmak, M.
Cappaccioli, R.J. Allen , Osser vatorio Astronomico di Trieste, p. 25
Moorwood , A., Glass, l.: 1982, Astron . Astrophys. 115, 84 Nandy , K., Morgan, D. H., Willis,
A.J., Wilson, R., Gondhale
kar, P. M., Houziaux, L.: 1980, Nature 283, 725
Oke, J.B.: 1974, Astrophys . J. Suppl. 27, 21
Osmer, P. S., Smith, M. G., Weedmann , D. W.: 1974, Astrophys. J.
192, 279
Osterbrock, D. E.: 1974, "Astrophysics of Gaseous Nebulae ", Freeman, San Francisco
Reif, K., Mebold, U., Goss, W. M., Van Woerden, H., Siegman,
B.: 1982, Astron. Astrophys. Suppl. 50, 451 Rieke, G.H.: 1976, Astrophys. J. 206, L15 Rosa, M.:
1980, Astron . Astrophys. 85, 121
Rosa, M., Joubert , M., Benvenuti , P.: 1984, Astron . Astrophys.
Suppl. 57, 361
Sandage, A., Brucato, R.: 1979, Astron . J. 84, 472
Sandage, A., Tamman , G.: 1981, A Revised Shapley-Ames Catalog of Bright Galaxies
Savage, B. D., Mathis, J.S.: 1977, Ann. Rev. Astron . Astrophys . 17,
73
Sersic, J.L., Carranza, M., Pastoriza, M.: 1972, Astrophys. Space
Sci. 19, 469
Stasinska, G.: 1980, Astron. Astrophys. 66, 257
Stasinska, G.: 1982, Astron. Astrophys . Suppl. 48, 299 Tarrab, I.: 1985, Astron. Astrophys. 150,
151
Terlevich, R., Melnick, J.: 1981, Monthly Notices Roy. Astron .
Soc. 195, 839
Thuan, T.X.: 1986, in Star Forming Dwarf Galaxies and Related Objects, Frontieres, Paris, p. 105
Van den Bergh, S.: 1972, J. Roy. Astron . Soc. Canada 66, 122 Veron , M.P.: 1984, Astron .
Astrophys . Suppl. 58, 665 Weedmann , D., Feldman , F. R., Balzano, V .A., Ramsey, L.W.,
Sramek, R.A., Wu, C.: 1981, Astrophys. J. 248, 105 Wegner, G.: 1979, Astrophys . Space Sci. 60, 15
Welch, G.: 1970, Astrophys . J. 161, 821
Welch, G., Wallerstein , G.: 1969, Pub!. Astron . Soc. Pacific 81, 23 Zamorano , J., Rego, M.:
1985, Astron . Astrophys . Suppl. 62, 173