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The impact of bars on disk breaks as probed by S^(4)G imaging



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Gil de Paz, Armando and otros, ... (2013) The impact of bars on disk breaks as probed by S^(4)G imaging. Astrophysical journal, 771 (1). ISSN 0004-637X

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Official URL: http://dx.doi.org/10.1088/0004-637X/771/1/59


We have analyzed the radial distribution of old stars in a sample of 218 nearby face-on disks, using deep 3.6 μm images from the Spitzer Survey of Stellar Structure in Galaxies. In particular, we have studied the structural properties of those disks with a broken or down-bending profile. We find that, on average, disks with a genuine single-exponential profile have a scale length and a central surface brightness which are intermediate to those of the inner and outer components of a down-bending disk with the same total stellar mass. In the particular case of barred galaxies, the ratio between the break and the bar radii (R_br/R_bar) depends strongly on the total stellar mass of the galaxy. For galaxies more massive than 10^10 M_☉, the distribution is bimodal, peaking at R_br/R_bar ~ 2 and ~3.5. The first peak, which is the most populated one, is linked to the outer Lindblad resonance of the bar, whereas the second one is consistent with a dynamical coupling between the bar and the spiral pattern. For galaxies below 10^10 M_☉, breaks are found up to ~10 R_bar, but we show that they could still be caused by resonances given the rising nature of rotation curves in these low-mass disks. While not ruling out star formation thresholds, our results imply that radial stellar migration induced by non-axisymmetric features can be responsible not only for those breaks at ~2 R_bar, but also for many of those found at larger radii.

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© 2013. The American Astronomical Society. All rights reserved. Artículo firmado por 28 autores. The authors are grateful to the entire S^(4)G team for their collective effort in this project. We thank S. Boissier for allowing us to use his disk evolution models. We also thank the referee for a very constructive report that helped to improve the quality of the paper. J.C.M.M. acknowledges financial support from NASA JPL/Spitzer Grant RSA 1374189 provided for the S4G project. J.C.M.M., K. S., and T. K. acknowledge support from the National Radio Astronomy Observatory, which is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. We acknowledge financial support from the People Programme (Marie Curie Actions) of the European Union's FP7/2007-2013/ to the DAGAL network under REA grant agreement No. PITN-GA-2011-289313.This work is based on data acquired with the Spitzer Space Telescope, and makes extensive use of the NASA/IPAC Extragalactic Database (NED), both of which are operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration (NASA). We also acknowledge the usage of the HyperLeda database (http://leda.univ-lyon1.fr).

Uncontrolled Keywords:Digital sky survey; Barred spiral galaxies; Edge-on galaxies; Spectral energy-distributions; Infrared surface photometry; Star-forming galaxies; Angular-momentum; Galactic disks; Pattern speeds; Radial-distribution
Subjects:Sciences > Physics > Astrophysics
Sciences > Physics > Astronomy
ID Code:35060
Deposited On:20 Jan 2016 14:49
Last Modified:10 Dec 2018 15:05

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