PMAS-PPAK integral-field spectroscopy of nearby Seyfert and normal spiral galaxies
I. The central kiloparsecs of NGC 4138
Bartakov´ a´ T.1, Jungwiert B.2,3,Sanchez´ S. F.4,5, Stoklasova´ I.2, Emsellem E.6, Ferruit P.7, Jahnke K.8, Mundell C.9, Tacconi-Garman L. E.6, Vergani D.10, Wisotzki L.11 1 Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Brno, Czech Republic; 2 Astronomical Institute, Academy of Science of the Czech Republic, Prague, Czech Republic; 3 Astronomical Institute of the Charles University in Prague, Czech Republic; 4 Centro de Estudios de F´ısica del Cosmos de Aragon´ (CEFCA), Teruel, Spain; 5 Centro Astronomico´ Hispano-Aleman,´ Calar Alto, Almer´ıa, Spain; 6 European Southern Observatory, Garching, Germany; 7 CRAL-Observatoire de Lyon, Saint-Genis-Laval, France; 8 Max-Planck-Institut fur Astronomie, Heidelberg, Germany; 9 Astrophysics Research Institute, Liverpool John Moores University, United Kingdom; 10 INAF-Osservatorio Astronomico di Bologna, Italy; 11 Astrophysical Institute Potsdam, Germany. email: [email protected]
Project overview These peculiarities are suspected to be related to a minor merger, however they could also be related to a destroyed Ratio Ha/Hb |2.5/*| Ratio [SII]6717/[SII]6731 |1.15/2.0| We study properties of ionized gas, gas/stellar kinematics bar, or a combination of both. New studies are necessary 30 6 30 2 5.5 1.9 and stellar populations in central regions (a few inner 20 20 to understand the galaxy history and mass transfer within 1.8 5 kiloparsecs) of four pairs of nearby Seyfert (NGC 5194, 10 10 1.7 the inner kiloparsecs. Our new data bring, for the first 4.5 1.6 0 0 NGC 4579, NGC 4151, NGC 4138) and normal spiral time, the 2D spectroscopic coverage of the whole region 4 1.5 -10 -10 galaxies (NGC 5505, NGC 3351, NGC 2985, NGC 3245). encompassed by the ring. DE offset [arcsec] 3.5 DE offset [arcsec] 1.4 1.3 -20 3 -20 1.2 -30 2.5 -30 While the key to the AGN fuelling and growth of the cen- -30 -20 -10 0 10 20 30 -30 -20 -10 0 10 20 30 We modelled the absorption features and slope of the RA offset [arcsec] RA offset [arcsec] tral supermassive black holes lies certainly closer to the spectra using the synthetic library of Bruzual & Charlot nucleus than 1 kpc, establishing the connection between (2003) to derive LOS stellar velocities and continuum flux Ratio [NII]6583/Ha (log scale) Ratio [OIII]5007/Hb |*/0.8| (log scale) 100 1 0.4 0.8 pc and kpc scale is one of unavoidable preliminary and to make correction for stellar absorption. Emission 30 30 0.3 0.6 steps: the velocity field at 100 pc can be very complex 20 20 lines were fitted by simple Gaussian functions to obtain 0.2 0.4 10 0.1 10 and its modeling requires a prior understanding of larger 0.2 line intensities, mean LOS velocities and velocity disper- 0 0 0 0 scales. Also, signatures of past inflow can be expected -0.1 sions. See Figs. 2. – 4. We also show spectral diagnostic -0.2 -10 -0.2 -10 DE offset [arcsec] DE offset [arcsec] in the kpc-scale radial gradients of stellar age, metallicity diagrams in Fig.5. to constrain ionization sources. -0.3 -0.4 -20 -20 and velocity dispersion. Our main goals are to: 1. look -0.4 -0.6 -30 -0.5 -30 -0.8 for systematic differences in central stellar populations -30 -20 -10 0 10 20 30 -30 -20 -10 0 10 20 30 RA offset [arcsec] RA offset [arcsec] and stellar/gaseous kinematics between Seyfert and non- Intensity in stellar continuum (log scale) [10-16erg/s/cm2/arcsec2] Stellar velocities |-300/300| [km/s] 30 4.5 30 300 active galaxies; 2. estimate inflow/outflow to/from the 200 Figure 4: Top left: Map of Hα/Hβ intensity ratio tracing 20 4 20 central kpc; 3. put constraints on the central kpc fuelling 10 10 100 the interstellar redenning: the highest extinction follows 3.5 via stellar mass-loss. The sample is intended as a pilot 0 0 0 the ring. Top right: Map of [SII]6717/[SII]6731 ratio, 3 study to demonstrate the efficacy of using the PMAS- -10 -10 -100 DE offset [arcsec] DE offset [arcsec] which is related to electron density distribution: highest 2.5 PPAK integral field spectrograph for the study of active -20 -20 -200 ratio values correspond to lowest electron densities. -30 2 -30 -300 and inactive galaxies over a uniquely wide range of size -30 -20 -10 0 10 20 30 -30 -20 -10 0 10 20 30 Bottom left and right: Maps of [NII]/Hα and OIII/Hβ scales. RA offset [arcsec] RA offset [arcsec] ratios show that gas in the inner region is most probably ionized by the AGN, while stars dominate the ionization Intensity in Ha (log scale) [10-16erg/s/cm2/arcsec2] Velocity in Ha |-200/200| [km/s] of the ring. Observations 30 2.5 30 200 150 20 2 20 NGC4138 Diagnostic diagram [OIII]/Hb vs. [NII]/Ha, S/N > 3 100 1.5 10 1.5 10 Eight nearby (0.001
6200 − 6900 ˚ 2 formation rate. The range A centered on Hα 20 20 1.5 0.0 was chosen to get more precise gas kinematics. 10 1.5 10 1 HII 0 1 0 -0.5 0.5 log ([OIII]5007 / Hbeta) -10 0.5 -10 LINER DE offset [arcsec] DE offset [arcsec] 0 integrated FOV -20 0 -20 -1.0 the brightest spaxel Ho et al. (1997) Dopita et al. (2000) -30 -0.5 -30 -0.5 Kewley et al. (2001) -30 -20 -10 0 10 20 30 -30 -20 -10 0 10 20 30 -1.5 RA offset [arcsec] RA offset [arcsec] -2.0 -1.5 -1.0 -0.5 0.0 0.5 log ([SII]6717 + [SII]6731 / Halpha) Figure 5: Spatialy resolved diagnostic diagrams; Intensity in Hb (log scale) [10-16erg/s/cm2/arcsec2] Intensity in [OII] (log scale) [10-16erg/s/cm2/arcsec2] ≤ 10′′ 30 2 30 2 central spaxels with R are red, those with 10′′ ≤ 25′′ 20 1.5 20 1.5
Poster presented at the conference “What drives the growth of black holes?”, Durham, England, July 26-29, 2010