2011/02/08 by J. C. Muñoz-Mateos, S. Boissier, A. Gil de Paz +8 · 86 citations
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Extinction (optical mineralogy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy rotation curve #Halo #Physics #Spiral galaxy #Star formation #Stars #Stellar mass #Stellar, planetary, and galactic studies #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.1088/0004-637x/731/1/10
published in The Astrophysical Journal 731(1), 10 (IOP Publishing) · Accepted for publication in ApJ. 32 pages in emulateapj format, 25 figures. The whole figureset of Fig. 2 can be downloaded from http://www.cv.nrao.edu/~jmunoz/f2_all.ps
arxiv created 2011/02/08 · openalex publication_date 2011/03/17 · arxiv updated 2015/05/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We analyze the evolution of 42 spiral galaxies in the Spitzer Infrared Nearby Galaxies Survey. We make use of ultraviolet (UV), optical, and near-infrared radial profiles, corrected for internal extinction using the total-infrared to UV ratio, to probe the emission of stellar populations of different ages as a function of galactocentric distance. We fit these radial profiles with models that describe the chemical and spectro-photometric evolution of spiral disks within a self-consistent framework. These backward evolutionary models successfully reproduce the multi-wavelength profiles of our galaxies, except for the UV profiles of some early-type disks for which the models seem to retain too much gas. From the model fitting we infer the maximum circular velocity of the rotation curve V C and the dimensionless spin parameter λ. The values of V C are in good agreement with the velocities measured in H i rotation curves. Even though our sample is not volume limited, the resulting distribution of λ is close to the lognormal function obtained in cosmological N -body simulations, peaking at λ ∼ 0.03 regardless of the total halo mass. We do not find any evident trend between λ and Hubble type, besides an increase in the scatter for the latest types. According to the model, galaxies evolve along a roughly constant mass–size relation, increasing their scale lengths as they become more massive. The radial scale length of most disks in our sample seems to have increased at a rate of 0.05–0.06 kpc Gyr −1 , although the same cannot be said of a volume-limited sample. In relative terms, the scale length has grown by 20%–25% since z = 1 and, unlike the former figure, we argue that this relative growth rate can be indeed representative of a complete galaxy sample.