THE IMPACT OF BARS ON DISK BREAKS AS PROBED BY S{sup 4}G IMAGING

Journal Article · Mon Jul 01 00:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/771/1/59· OSTI ID:22140186

Munoz-Mateos, Juan Carlos; Sheth, Kartik; Kim, Taehyun ^[1]; Gil de Paz, Armando ^[2]; Meidt, Sharon ^[3]; Athanassoula, E.; Bosma, Albert ^[4]; Comeron, Sebastien; Laine, Jarkko; Laurikainen, Eija ^[5]; Elmegreen, Debra M. ^[6]; Elmegreen, Bruce G. ^[7]; Erroz-Ferrer, Santiago; Knapen, Johan H. ^[8]; Gadotti, Dimitri A. ^[9]; Hinz, Joannah L. ^[10]; Ho, Luis C.; Madore, Barry F. ^[11]; Holwerda, Benne ^[12]; others, and

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1. National Radio Astronomy Observatory/NAASC, 520 Edgemont Road, Charlottesville, VA 22903 (United States)
2. Departamento de Astrofisica, Universidad Complutense de Madrid, E-28040 Madrid (Spain)
3. Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)
4. Aix Marseille Universite, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France)
5. Department of Physical Sciences/Astronomy Division, University of Oulu, FIN-90014 (Finland)
6. Department of Physics and Astronomy, Vassar College, Poughkeepsie, NY 12604 (United States)
7. IBM Research Division, T.J. Watson Research Center, Yorktown Hts., NY 10598 (United States)
8. Instituto de Astrofisica de Canarias, E-38205 La Laguna (Spain)
9. European Southern Observatory, Casilla 19001, Santiago 19 (Chile)
10. University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85721 (United States)
11. The Observatories, Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
12. European Space Agency, ESTEC, Keplerlaan 1, 2200-AG, Noordwijk (Netherlands)

We have analyzed the radial distribution of old stars in a sample of 218 nearby face-on disks, using deep 3.6 {mu}m 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{sub br}/R{sub bar}) depends strongly on the total stellar mass of the galaxy. For galaxies more massive than 10{sup 10} M{sub Sun }, the distribution is bimodal, peaking at R{sub br}/R{sub bar} {approx} 2 and {approx}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{sup 10} M{sub Sun }, breaks are found up to {approx}10 R{sub 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 {approx}2 R{sub bar}, but also for many of those found at larger radii.

• OSTI ID: 22140186
• Journal Information: Astrophysical Journal, Vol. 771, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
AXIAL SYMMETRY
BENDING
BRIGHTNESS
COUPLING
EVOLUTION
GALAXIES
IMAGES
MASS
MIGRATION
PEAKS
PHOTOMETRY
PROBES
ROTATION
SPATIAL DISTRIBUTION
STARS
SURFACES