Star formation in H I tails: HCG 92, HCG 100 and six interacting systems

Autor(es)

de Mello, D. F. ^{[1, 2]} ; Urrutia-Viscarra, F. ^[3] ; Mendes de Oliveira, C. ^[3] ; Torres-Flores, S. ^[4] ; Carrasco, E. R. ^[5] ; Cypriano, E. ^[3]

Afiliação do(s) autor(es)

^[1] Catholic Univ Amer, Dept Phys, Washington, DC 20064 - USA

^[2] NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 - USA

^[3] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Dept Astron, BR-05508090 Sao Paulo - Brazil

^[4] Univ La Serena, Dept Fis, La Serena - Chile

^[5] So Operat Ctr, Gemini Observ AURA, La Serena - Chile

• Tipo de documento: Artigo Científico
• Fonte: Monthly Notices of the Royal Astronomical Society; v. 426, n. 3, p. 2441-2451, NOV 2012.
• Citações Web of Science: 13

Resumo

We present new Gemini spectra of 14 new objects found within the H?i tails of Hickson Compact Groups (HCGs) 92 and 100. Nine of them are Galaxy Evolution Explorer (GALEX) far-ultraviolet (FUV) and near-ultraviolet (NUV) sources. The spectra confirm that these objects are members of the compact groups and have metallicities close to solar, with an average value of 12+log(O/H) similar to 8.5. They have average FUV luminosities 7 x 10(40)?erg?s-1 and very young ages (<100?Myr), and two of them resemble tidal dwarf galaxy (TDG) candidates. We suggest that they were created within gas clouds that were ejected during galaxygalaxy interactions into the intergalactic medium, which would explain the high metallicities of the objects, inherited from the parent galaxies from which the gas originated. We conduct a search for similar objects in six interacting systems with extended H?i tails: NGC 2623, NGC 3079, NGC 3359, NGC 3627, NGC 3718 and NGC 4656. We found 35 ultraviolet (UV) sources with ages < 100?Myr; however, most of them are on average less luminous/massive than the UV sources found around HCG 92 and HCG 100. We speculate that this might be an environmental effect and that compact groups of galaxies are more favourable to TDG formation than other interacting systems. (AU)

• Processo FAPESP: 07/07973-3 - A cinemática interna de galáxias em grupos compactos de Hickson
• Beneficiário: Sergio Patricio Torres Flores
• Linha de fomento: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 07/06436-4 - Mapeamento de regiões de formação estelar intergalácticas, em sistemas de interação
• Beneficiário: Paula Maria Fernanda Urrutia Viscarra
• Linha de fomento: Bolsas no Brasil - Mestrado
• Processo FAPESP: 06/56213-9 - Nova física no espaço: formação e evolução de estruturas no universo
• Beneficiário: Claudia Lucia Mendes de Oliveira
• Linha de fomento: Auxílio à Pesquisa - Temático