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Position-velocity diagrams of ionized gas in the inner regions of disk galaxies

J. G. Funes·E. M. Corsini·M. Cappellari·A. Pizzella·J. C. Vega Beltran·C. Scarlata·F. Bertola
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Abstract

We use long-slit spectroscopy along the major axis of a sample of 23 nearby disk galaxies to study the kinematic properties of the ionized-gas component in their inner regions. For each galaxy, we derive the position-velocity diagram of the ionized gas from its emission lines. We discuss the variety of shapes observed in such position-velocity diagrams by comparing the gas velocity gradient, velocity dispersion and integrated flux measured in the inner (r +/-1'') and outer regions (r +/-4''). This kind of analysis allows the identification of galaxies which are good candidates to host a circumnuclear Keplerian gaseous disk rotating around a central mass concentration, and to follow up with Hubble Space Telescope observations.

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J. G. Funes, E. M. Corsini, M. Cappellari, A. Pizzella, J. C. Vega Beltran, C. Scarlata, F. Bertola. 2002-04-01. Position-velocity diagrams of ionized gas in the inner regions of disk galaxies. https://doi.org/10.1051/0004-6361%3A20020406

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