The effect of disk inclination on the Main Sequence of star forming
  galaxies
  We use the Sloan Digital Sky Survey (SDSS) database to explore the effect of
the disk inclination angle on the derived star formation rate (SFR), hence on
the slope and width of the Main Sequence (MS) relation for star-forming
galaxies. We find that SFRs for nearly edge-on disks are underestimated by
factors ranging from $\sim$ 0.2 dex for low mass galaxies up to $\sim$ 0.4 dex
for high mass galaxies. This results in a substantially flatter MS relation for
high-inclination disks compared to that for less inclined ones, though the
global effect over the whole sample of star-forming galaxies is relatively
minor, given the small fraction of high-inclination disks. However, we also
find that galaxies with high-inclination disks represent a non negligible
fraction of galaxies populating the so-called green valley, with derived SFRs
intermediate between the MS and those of quenched, passively evolving galaxies.
