Surface Brightness Plateau in S4G Galaxies

Alan Sipols, Alex Pavlovich
2020 Galaxies  
Using 3.6-μm data from 2112 galaxies, we show that, contrary to widely held expectations of a continuous steep decline, radial surface brightness profiles of galaxies tend to flatten and form extended plateaus beyond 27–28 magAB/arcsec². This phenomenon could be explained by the presence of extended stellar populations dominated by low-mass stars in galactic outskirts. The flattening of radial brightness profiles questions the artificial exponential extrapolations of brightness data and the
more » ... ss data and the automatic assumption that light always declines considerably faster than mass density, presenting an empirical challenge for the dark matter hypothesis.
doi:10.3390/galaxies8020048 fatcat:rmz4ousicfdiblpaczyq52px54