Low Surface Brightness ( LSB ) galaxies are dominated by dark matter , and their rotation curves thus reflect their dark matter distribution .
Recent high-resolution rotation curves suggest that their dark matter mass-density distributions are dominated by a constant-density core .
This seems inconsistent with the predictions of Cold Dark Matter ( CDM ) models which produce halos with compact density cusps and steep mass-density profiles .
However , the observationally determined mass profiles may be affected by non-circular motions , asymmetries and offsets between optical and dynamical centres , all of which tend to lower the observed slopes .
Here we determine the impact of each of these effects on a variety of halo models , and compare the results with observed mass-density profiles .
Our simulations suggest that no single systematic effect can reconcile the data with the cuspy CDM halos .
The data are best described by a model with a soft core with an inner power-law mass-density slope \alpha = -0.2 \pm 0.2 .
However , no single universal halo profile provides a completely adequate description of the data .