| Texto completo | |
| Autor(es): |
Torres-Flores, S.
[1, 2, 3, 4]
;
Mendes de Oliveira, C.
[2]
;
de Mello, D. F.
[5, 6]
;
Scarano, Jr., S.
[2]
;
Urrutia-Viscarra, F.
[2]
Número total de Autores: 5
|
| Afiliação do(s) autor(es): | [1] Univ La Serena, Dept Fis, La Serena - Chile
[2] Univ Sao Paulo, Dept Astron, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo - Brazil
[3] Univ Aix Marseille 1, OAMP, Lab Astrophys Marseille, F-13388 Marseille 13 - France
[4] CNRS, F-13388 Marseille 13 - France
[5] Catholic Univ Amer, Washington, DC 20064 - USA
[6] NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 - USA
Número total de Afiliações: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Monthly Notices of the Royal Astronomical Society; v. 421, n. 4, p. 3612-3621, APR 2012. |
| Citações Web of Science: | 15 |
| Resumo | |
We have searched for young star-forming regions around the merger remnant NGC 2782. By using Galaxy Evolution Explorer far-ultraviolet and near-ultraviolet imaging and H i data we found seven ultraviolet sources, located at distances greater than 26 kpc from the centre of NGC 2782, and coinciding with its western H i tidal tail. These regions were resolved in several smaller systems when Gemini/Gemini multi-object spectrograph (GMOS) r-band images were used. We compared the observed colours to stellar population synthesis models and found that these objects have ages of similar to 1 to 11 Myr and masses ranging from 103.9 to 104.6 M circle dot. By using Gemini/GMOS spectroscopic data we confirm memberships and derive high metallicities for three of the young regions in the tail (12+log(O/H) = 8.74 +/- 0.20, 8.81 +/- 0.20 and 8.78 +/- 0.20). These metallicities are similar to the value presented by the nuclear region of NGC 2782 and also similar to the value presented for an object located close to the main body of NGC 2782. The high metallicities measured for the star-forming regions in the gaseous tidal tail of NGC 2782 could be explained if they were formed out of highly enriched gas which was once expelled from the centre of the merging galaxies when the system collided. An additional possibility is that the tail has been a nursery of a few generations of young stellar systems which ultimately polluted this medium with metals, further enriching the already pre-enriched gas ejected to the tail when the galaxies collided. (AU) | |
| Processo FAPESP: | 09/05181-8 - Determinação da Orientação Espacial de Galáxias Utilizando Braços Espirais e Campos de Velocidade |
| Beneficiário: | Sergio Scarano Junior |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 06/56213-9 - Nova física no espaço: formação e evolução de estruturas no universo |
| Beneficiário: | Claudia Lucia Mendes de Oliveira |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 07/07973-3 - A cinemática interna de galáxias em grupos compactos de Hickson |
| Beneficiário: | Sergio Patricio Torres Flores |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado Direto |
| Processo FAPESP: | 07/06436-4 - Mapeamento de regioes de formaçao estelar intergalácticas, em sistemas de interaçao |
| Beneficiário: | Paula Maria Fernanda Urrutia Viscarra |
| Modalidade de apoio: | Bolsas no Brasil - Mestrado |