| Full text | |
| Author(s): |
Total Authors: 3
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| Affiliation: | [1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508900 Sao Paulo, SP - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | Astronomy & Astrophysics; v. 576, APR 2015. |
| Web of Science Citations: | 1 |
| Abstract | |
Context. Messier 81 has the nearest active nucleus with broad H alpha emission. A detailed study of this galaxy's centre is important for understanding the innermost structure of the AGN phenomenon. Aims. Our goal is to seek previously undetected structures using additional techniques to reanalyse a data cube obtained with the GMOS-IFU installed on the Gemini North telescope (Schnorr Muller et al. 2011, MNRAS, 413, 149). Methods. We analysed the data cube using techniques of noise reduction, spatial deconvolution, starlight subtraction, PCA tomography, and comparison with HST images. Results. We identified a hot bubble with T > 43 500 K that is associated with strong emission of {[}N II] lambda 5755 angstrom and a high {[}O I] lambda 6300/H alpha ratio; the bubble displays a bluish continuum, surrounded by a thin shell of H alpha + {[}N II] emission. We also reinterpret the outflow found by Schnorr Muller et al. (2011), showing that the blueshifted cone nearly coincides with the radio jet, as expected. Conclusions. We interpret the hot bubble as having been caused by post starburst events that left one or more clusters of young stars, similar to the ones found at the centre of the Milky Way, such as the Arches and the IRS 16 clusters. Shocked structures from combined young stellar winds or supernova remnants are probably the cause of this hot gas and the low ionization emission. (AU) | |
| FAPESP's process: | 12/21350-7 - Nuclear and circumnuclear low ionization emission in massive galaxies. |
| Grantee: | Tiago Vecchi Ricci |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 11/20224-5 - PCA tomography and kinematics of the nucleus of the LINER galaxy M81 |
| Grantee: | Louise Maria Giansante Martins |
| Support Opportunities: | Scholarships in Brazil - Scientific Initiation |