@inproceedings{8e4ededfc56b4f19923e158d773b0b95,
title = "Sings observations of spiral galaxies evidence for secular evolution",
abstract = "One process in the secular evolution of galaxies is the formation of pseudo-bulges. The formation of these pseudo-bulges requires the inflow of gas to smaller radii. If the inflow rate is faster than the rate of star formation, a central concentration of gas will form. In this paper we present radial profiles of stellar and 8 micron emission from Polycyclic Aromatic Hydrocarbons (PAHs) for 11 spiral galaxies to investigate whether the interstellar medium in these galaxies contains a central concentration above that expected from the exponential disk. We find that in five of the 11 galaxies there is a central excess in the 8 micron and CO emission above the inner extrapolation of an exponential disk. In particular, all four barred galaxies in the sample have strong central excesses in both 8 micron and CO emission. This correlation suggests that the excess seen in the CO profiles is, in general, not simply due to a radial increase in the CO emissivity.",
keywords = "Dust, Extinction, Galaxies: ISM, Galaxies: Structure, Infrared: Galaxies",
author = "Michael Regan and Thornley, {Michele D.} and Vogel, {Stuart N.} and Kartik Sheth and Draine, {Bruce T.} and Hollenbach, {David J.} and Martin Meyer and Dale, {Daniel A.} and Engelbracht, {Charles W.} and Kennicutt, {Robert C.} and Lee Armus and Daniela Calzetti and Gordon, {Karl D.} and George Helou and Claus Leitherer and Sangeeta Malhotra and Rieke, {George H.} and Rieke, {Marcia J.}",
note = "Publisher Copyright: {\textcopyright} 2007, Springer Netherlands. All rights reserved.; International Conference on Island Universe: Structure and Evolution of Disk Galaxies, 2005 ; Conference date: 03-07-2005 Through 05-07-2005",
year = "2007",
doi = "10.1007/978-1-4020-5573-7_58",
language = "English (US)",
isbn = "9780387727677",
series = "Astrophysics and Space Science Proceedings",
publisher = "Springer Science and Business Media B.V.",
pages = "341--346",
editor = "{De Jong}, R.S.",
booktitle = "Astrophysics and Space Science Proceedings",
}