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Deep spectroscopy of the dwarf spheroidal NGC 185

Published online by Cambridge University Press:  30 August 2012

Denise R. Gonçalves ,
Laura Magrini ,
Lucimara P. Martins ,
Ana M. Teodorescu ,
Cintia Quireza  and
Gaia Lanfranchi
Denise R. Gonçalves
Affiliation:
UFRJ - Observatório do Valongo, Ladeira Pedro Antonio 43, 20080-090 Rio de Janeiro, Brazil. email: [email protected] Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT London, UK
Laura Magrini
Affiliation:
INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze, Italy.
Lucimara P. Martins
Affiliation:
NAT - Universidade Cruzeiro do Sul, Rua Galvão Bueno 868, 01506-000 São Paulo, Brazil.
Ana M. Teodorescu
Affiliation:
Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, HI 96822 Honolulu, USA.
Cintia Quireza
Affiliation:
UFRJ - Observatório do Valongo, Ladeira Pedro Antonio 43, 20080-090 Rio de Janeiro, Brazil. email: [email protected]
Gaia Lanfranchi
Affiliation:
INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze, Italy.
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Abstract

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Dwarf galaxies are crucial to understand the formation and evolution of galaxies, since they constitute the most abundant galaxy population. Abundance ratios and their variations due to star formation and inflow/outflow of gas are key constraints to chemical evolution models. The determination of these abundances in the dwarf galaxies of the Local Universe is thus of extreme importance. NGC 185 is one of the four brightest dwarf companions of M31, but unlike the other three it has an important content of gas and dust. Interestingly enough, in an optical survey of bright nearby galaxies NGC 185 was classified as a Seyfert galaxy based on its integrated emission-line ratios in the nuclear regions. However, although its emission lines formally place it in the category of Seyfert it is probable that this galaxy does not contain a genuine active nucleus. In this contribution, we resume, firstly, our results of an empirical study of the galaxy, on which we characterise its emission-line population and obtain planetary nebulae abundance ratios (Gonçalves et al. 2012). And, secondly, we discuss our attempt to identify the possible ionization mechanisms for NGC 185 enlighting the controversial classification of this galaxy dwarf spheroidal (dSph) as well as Seyfert, via stellar population synthesis and chemical evolution modelling (Martins et al. 2011).

Keywords

Galaxies: dwarfgalaxies: abundancesLocal Groupplanetary nebulae: generalsupernova: generalbinaries: symbiotic
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 7 , Symposium S283: Planetary Nebulae: An Eye to the Future , July 2011 , pp. 370 - 371
Copyright
Copyright © International Astronomical Union 2012

References

Gonçalves, D. R., Magrini, L., Martins, L. P., Teodorescu, A. M., & Quireza, C. 2012, MNRAS, 419, 854 CrossRefGoogle Scholar
Ho, L., Filippenko, A. V., & Sargent, W. L. W. 1997, ApJS, 112, 315 CrossRefGoogle Scholar
Lanfranchi, G. & Matteucci, F. 2003, MNRAS, 345, 71 CrossRefGoogle Scholar
Martins, L. P., Lanfranchi, G., Gonçalves, D. R., Magrini, L., Teodorescu, A. M., & Quireza, C. 2011, MNRAS, submittedGoogle Scholar
Richer, M. G. & McCall, M. L. 2008, ApJ, 684, 1190 CrossRefGoogle Scholar