We study the spatially-resolved stellar specific angular momentum j _ { * } in a high-quality sample of 24 CALIFA galaxies covering a broad range of visual morphology , accounting for stellar velocity and velocity dispersion .
The shape of the spaxel-wise probability density function of normalised s = j _ { * } / j _ { *mean } , { PDF } ( s ) , deviates significantly from the near-universal initial distribution expected of baryons in a dark matter halo and can be explained by the expected baryonic effects in galaxy formation that remove and redistribute angular momentum .
Further we find that the observed shape of the { PDF } ( s ) correlates significantly with photometric morphology , where late-type galaxies have a { PDF } ( s ) that is similar to a normal distribution , whereas early types have a strongly-skewed { PDF } ( s ) resulting from an excess of low-angular momentum material .
Galaxies that are known to host pseudobulges ( bulge Sérsic index n _ { b } < 2.2 ) tend to have less skewed bulge { PDF } ( s ) , with skewness ( b _ { 1 rb } ) \lesssim 0.8 .
The { PDF } ( s ) encodes both kinematic and photometric information and appears to be a robust tracer of morphology .
Its use is motivated by the desire to move away from traditional component-based classifications which are subject to observer bias , to classification on a galaxy ’ s fundamental ( stellar mass , angular momentum ) properties .
In future , { PDF } ( s ) may also be useful as a kinematic decomposition tool .