NGC 6744: A Nearby Milky Way Twin with a Very Low-luminosity AGN

Autor(es)

da Silva, Patricia ^[1] ; Steiner, J. E. ^[1] ; Menezes, R. B. ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Dept Astron, BR-05508090 Sao Paulo, SP - Brazil

^[2] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210580 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ASTROPHYSICAL JOURNAL; v. 861, n. 2 JUL 10 2018.
• Citações Web of Science: 0

Resumo

NGC 6744 is the nearest and brightest south-hemisphere galaxy with a morphological type similar to that of the Milky Way. Using data obtained with the Integral Field Unit of the Gemini South Multi-Object Spectrograph, we found that this galaxy has a nucleus with LINER (Low Ionization Nuclear Emission Line Region) surrounded by three line emitting regions. The analysis of the Hubble Space Telescope archival images revealed that the nucleus is associated with a blue compact source, probably corresponding to the active galactic nucleus (AGN). The circumnuclear emission seems to be part of the extended narrow line region of the AGN. One of these regions, located similar to 1. southeast of the nucleus, seems to be associated with the ionization cone of the AGN. The other two regions are located similar to 1. south and similar to 0 6 northeast of the nucleus and are not aligned with the gaseous rotating disk. Spectral synthesis shows evidence that this galaxy may have gone through a merger about one billion years ago. On the basis of the kinematic behavior, we found a gaseous rotating disk, not co-aligned with the stellar disk. Given the relative degree of ionization and luminosities of the nuclear and circumnuclear regions, we suggest that the AGN was more luminous in the past and that the current circumnuclear emissions are echoes of that phase. (AU)

• Processo FAPESP: 11/51680-6 - Explorando o universo: da formação de galáxias aos planetas tipo-terra, com o Telescópio Gigante Magellan
• Beneficiário: João Evangelista Steiner
• Linha de fomento: Auxílio à Pesquisa - Projetos Especiais