Nuclear Starbursts in Nearby Seyfert Galaxies
نویسندگان
چکیده
Active galaxies are often associated with starbursts, which are possible sources of fuelling for the nuclear black holes. By means of optical (3500 − 7500 Å) spectroscopic and narrow-band photometric data (Hα + [NII]λ6548,6583 and [OIII]λ5007) it is possible to detect starburst features in active nuclei and to study the correlation with Seyfert type and the surrounding environment. Here we present evidences of young stellar populations (HI high order Balmer lines) and extended Hα emission (indicative of HII regions) in 6 nearby Seyfert galaxies (z < 0.02). These very preliminary results seem to suggest that the nuclear starburst presence does not depend on the Seyfert type, favouring the hypothesis of the AGN Unified Model. By estimating the present SFR (< 10 years) and recent SFR (< 10 years) we observe that these objects have experienced most of star formation episodes in past epochs. This supports the hypothesis of a starburstAGN connection, favouring an evolutionary scenario in which the AGN survives to the starburst.
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