2012/04/13 by Judit Bakos, Ignacio Trujillo, Bakos, Judit +1 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph.CO
paper · pdf · doi:10.48550/arxiv.1204.3082
Submitted to ApJ. Comments are welcome
arxiv created 2012/04/13 · openalex publication_date 2012/04/13 · arxiv updated 2012/04/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Using SDSS Stripe82 data we have obtained deep radial surface brightness profiles of 7 face-on to intermediate inclined late-type spirals down to ∼ 30 mag arcsec-2 in the r'-band. We do not find any evidence for a sharp cut-off of the light distribution of the disks but a smooth continuation into the stellar halos of galaxies. Stellar halos start to affect the surface brightness profiles of the galaxies at ∼ 28 mag arcsec-2, and at a radial distance of ∼ 4-10 inner scale-lengths. We find that the light contribution from the stellar halo could be responsible of previous classification of surface brightness profiles as Type III in late-type galaxies. In order to estimate the contribution of the stellar halo light to the total galaxy light, we carried out a Bulge/Disk/Stellar Halo decomposition by simoultaneously fitting all components. The light contribution of the halo to the total galaxy light varies from ~ 1% to ~ 5%, but in case of ongoing mergers, the halo light fraction can be as high as ~ 10%, independently of the luminosities of the galaxies. We have also explored the integrated (g'-r') color of the stellar halo of our galaxies. We find (g'-r') colors ranging from ~ 0.4 to ~ 1.2. By confronting these colors with model predictions, we encounter problems to fit our very red colors onto stellar population grids with conventional IMFs. Very red halo colors can be attributed to stellar populations dominated by very low mass stars of low to intermediate metallicity produced by bottom-heavy IMFs.