AGN-starburst connection in NGC7582: Gemini near-infrared spectrograph integral field unit observations

We analyse two-dimensional near-infrared K-band spectra from the inner 660 x 315 pc(2) of the Seyfert galaxy NGC7582 obtained with the Gemini near-infrared spectrograph integral field unit at a spatial resolution of approximate to 50 pc and spectral resolving power R approximate to 5900. The nucleus harbours an unresolved source well reproduced by a blackbody of temperature T approximate to 1050 K, which we attribute to emission by circumnuclear dust located closer than 25 pc from the nucleus, with a total mass of approximate to 3 x 10(-3) M-circle dot. Surrounding the nucleus, we observe a ring of active star formation, apparently in the Galactic plane, with a radius of approximate to 190 pc, an age of approximate to 5 Myr and a total mass of ionized gas of approximate to 3 x 10(6) M-circle dot. The radiation of the young stars in the ring accounts for at least 80 per cent of the ionization observed in the Br gamma emitting gas, the remaining being due to the radiation emitted by the active nucleus. The stellar kinematics was derived using the CO absorption band at 2.29 mu m and reveals: (i) a distorted rotation pattern in the radial velocity field with kinematic centre apparently displaced from the nuclear source by a few tens of parsec; (ii) a high-velocity dispersion in the bulge of sigma(*) = 170 km s(-1) and (iii) a partial ring of sigma(*) = 50 km s(-1), located close to the Br gamma emitting ring, but displaced by approximate to 50 pc towards the nucleus, interpreted as due to stars formed from cold gas in a previous burst of star formation. The kinematics of the ionized gas shows a similar rotation pattern to that of the stars, plus a blueshifted component with velocities >= 100 km s(-1) interpreted as due to an outflow along the ionization cone, which was partially covered by our observations. The mass outflow rate in the ionized gas was estimated as. (M) over dot(HII)approximate to 0.05 M-circle dot yr(-1), which is one order of magnitude larger than the accretion rate to the active galactic nuclei (AGN), indicating that the outflowing gas does not originate in the AGN, but is instead the circumnuclear gas from the host galaxy being pushed away by a nuclear outflow. The flux distribution and kinematics of the hot molecular gas, traced by the H-2 lambda 2.22 mu m emission line, suggest most of this gas is in the Galactic plane. An excess blueshift along PA approximate to-70 degrees, where a nuclear bar has been observed, can be interpreted as an inflow towards the nucleus. We thus conclude that the H-2 kinematics traces the feeding of the AGN, while the ionized gas kinematics traces its feedback via the outflows. An AGN-starburst connection in the nucleus of NGC7582 is supported by the ratio between the mass accretion rate and the star formation rate in the circumnuclear region of approximate to 0.26 per cent, which is close to the expected relation between the mass of the supermassive black holes and that of the host galaxy bulge in galaxies (the Magorrian relation).