We derive inner dark matter halo density profiles for a sample of 165 low-mass galaxies using rotation curves obtained from high-quality , long-slit optical spectra assuming minimal disks and spherical symmetry .
For \rho ( r ) ~ { } \sim~ { } r ^ { - \alpha } near the galaxy center we measure median inner slopes ranging from \alpha _ { m } = 0.22 \pm 0.08 to 0.28 \pm 0.06 for various subsamples of the data .
This is similar to values found by other authors and in stark contrast to the intrinsic cusps ( \alpha _ { int } \sim 1 ) predicted by simulations of halo assembly in cold dark matter ( CDM ) cosmologies .
To elucidate the relationship between \alpha _ { m } and \alpha _ { int } in our data , we simulate long-slit observations of model galaxies with halo shapes broadly consistent with the CDM paradigm .
Simulations with \alpha _ { int } = 1 / 2 and 1 recover both the observed distribution of \alpha _ { m } and correlations between \alpha _ { m } and primary observational parameters such as distance and disk inclination , whereas those with \alpha _ { int } = 5 / 4 are marginally consistent with the data .
Conversely , the hypothesis that low-mass galaxies have \alpha _ { int } = 3 / 2 is rejected .
While the simulations do not imply that the data favor intrinsic cusps over cores , they demonstrate that the discrepancy between \alpha _ { m } and \alpha _ { int } \sim 1 for our sample does not necessarily imply a genuine conflict between our results and CDM predictions : rather , the apparent cusp/core problem may be reconciled by considering the impact of observing and data processing techniques on rotation curves derived from long-slit spectra .