NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-05-20 T02:36:09 PDT
Help | Comment | NED Home

For refcode 2013A&A...560A..14P:
Retrieve 1 NED object in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by European Southern Observatory (ESO). Reproduced by permission
2013A&A...560A..14P The external origin of the polar gaseous disk of the S0 galaxy IC 5181 Pizzella, A.; Morelli, L.; Corsini, E. M.; Dalla Bonta, E.; Cesetti, M. Abstract. Context. Galaxies accrete material from the environment through acquisition and merging events. These processes contribute to galaxy assembly and leave their fingerprints on the galactic morphology, internal kinematics of gas and stars, and stellar populations. Aims: We study the nearby S0 galaxy IC 5181 to address the origin of the ionized gas component that orbits the galaxy on polar orbits. Methods: We measure the surface brightness distribution of the stars and ionized gas of IC 5181 from broadband and narrow-band imaging. The structural parameters of the galaxy are obtained with a photometric decomposition assuming a Sersic and exponential profile for the bulge and disk, respectively. We measure the ionized-gas and stellar kinematics and the line strengths of the Lick indices of the stellar component along both the major and minor axis. The age, metallicity, and [{alpha}/Fe] enhancement of the stellar populations are derived using single stellar population models with variable element abundance ratios. The ionized-gas metallicity is obtained from the equivalent width of the emission lines. Results: The galaxy IC 5181 is a morphologically undisturbed S0 galaxy with a classical bulge made by old stars with super solar metallicity and overabundance. Stellar age and metallicity decrease in the disk region. The galaxy hosts a geometrically and kinematically decoupled component of ionized gas. It is elongated along the galaxy minor axis and in orthogonal rotation with respect to the galaxy disk. Conclusions: We interpret the kinematical decoupling as suggesting that there is a component of gas, which is not related to the stars and having an external origin. The gas was accreted by IC 5181 on polar orbits from the surrounding environment. Based on observation collected at the European Southern Observatory for the programme 63.N-0327(A).Tables 1-3 are available in electronic form at http://www.aanda.org Key words: galaxies: photometry, galaxies: kinematics and dynamics, galaxies: stellar content, galaxies: individual: IC 5181, galaxies: formation
Retrieve 1 NED object in this reference.
Please click here for ADS abstract

Back to NED Home