ON THE EVOLUTIONARY STATUS OF LOW-METALLICITY BLUE COMPACT GALAXIES
DOI:
https://doi.org/10.18524/1810-4215.1999.12.93116Ключові слова:
Galaxies, irregular, evolutionАнотація
A remarkably small scatter in the N/O ratios for the HII regions in low-metallicity blue compact galaxies (BCG) has been found recently by Izotov and Thuan. They have concluded that these galaxies are presently undergoing their first burst of star formation, and that nitrogen measured in these galaxies is produced by massive stars in the current star formation burst only. Here it has been tested whether this interpretation is compatible with other observational data and with the existing ideas on the chemical evolution of galaxies. It has been found that the existence of systems (damped L absorbers) in which the N/Si ratios are lower than in low-metallicity BCGs and the chemical homogeneity of star-forming BCGs are in conflict with conclusion that the massive stars from current star formation event are responsible for the nitrogen abundance measured in low-metallicity BCGs. The low-metallicity BCGs seem to be systems with a small amount of old underlying stellar population over which the current star formation burst is superposed; only the stars from the previous star formation event(s) are responsible for the observed chemical composition in the giant HII regions in these galaxies.Посилання
Carbon D.F., Barbuy B., Kraft R.P., Friel E.D., Suntze N.B.: 1987, P.A.S.P., 99, 335
Cunha K., Lambert D.L.: 1994, Ap.J., 426, 170
Edmunds M.G., Pagel B.E.J.: 1978, M.N.R.A.S., 185, 77p
Garnett D.R.: 1990, Ap.J., 363, 142
Izotov Y.I., Lipovetsky V.A., Chaee F.H., Foltz C.B., Guseva N.G., Kniazev A.Y.: 1997, Ap.J., 476, 698
Izotov Y.I., Thuan T.X.: 1999, Ap.J., 511, 639
Kobulnicky H.A.: 1999, astro-ph 9901260
Kobulnicky H.A., Skillman E.D.: 1997, Ap.J., 489, 636
Kobulnicky H.A., Skillman E.D.: 1998, Ap.J., 497, 601
Kunth D., Sargent W.L.W.: 1986, Ap.J., 300, 496
Lu L., Sargent W.L.W., Barlow T.A.: 1998, Ap.J., 115, 55
Marconi G., Matteucci F., Tosi M.: 1994, M.N.R.A.S., 270, 35
Marigo P., Bressan A., Chiosi C.: 1996, As.Ap., 313, 545
Marigo P., Bressan A., Chiosi C.: 1998, As.Ap., 331, 564
Martin C.L.: 1996, Ap.J., 465, 680
Papaderos P., Izotov Y.I., Fricke K.J., Thuan T.X., Guseva N.G.: 1998, As.Ap., 338, 43
Pilyugin L.S.: 1992, As.Ap., 260, 58
Pilyugin L.S.: 1993, As.Ap., 277, 42
Pilyugin L.S.: 1999, As.Ap., 346, 428
Pilyugin L.S., Edmunds M.G.: 1996, As.Ap., 313, 792
Renzini A., Voli M.: 1981, As.Ap., 94, 175
Searle L., Sargent W.L.W.: 1972, Ap.J., 173, 25
Thuan T.X., Izotov Y.I., Lipovetsky V.A.: 1995, Ap.J., 445, 108
Tosi M.: 1994, in Dwarf Galaxies, Eds. Meylan G., Prugniel P., (Garching: Europen Southern Observatory), p. 465
van den Hoek L.B., Groenewegen M.A.T.: 1997, As.Ap.S.S., 123, 305
##submission.downloads##
Опубліковано
Номер
Розділ
Ліцензія
Авторське право (c) 2017 Odessa Astronomical Publications
Ця робота ліцензується відповідно до Creative Commons Attribution-NonCommercial 4.0 International License.
Відповідно Закону України про авторське право і суміжні права N 3792-XII від 23 грудня 1993 року
