FDG RESULTS FOR NGC 6503

NGC 6503 is a disk-dominated field dwarf spiral galaxy approximately 18 million light-years away in the constellation of Draco. This spiral galaxy shows bright blue regions typically related to star formation, bright red regions of gas along its spiral arms, and dark-brown dust areas in the galaxy's center and arms, as seen in images taken by the NASA/ESA Hubble Space Telescope. NFDG results for NGC 6503 are described in the figure below: the top panel shows the variable dimension D(R) (red-solid curve) computed with the main NFDG model, and the new mass-dimension function D_m(R) (blue-dashed curve), computed with the NFDG field equation. Both dimensions are very close to values in the range D=1.9-2.1, over most of the radial range. This is typical NFDG behavior for galactic structures dominated by an axially-symmetric stellar disk component. Bottom panel: NFDG galactic rotation curves compared with SPARC data. There is perfect agreement between the main NFDG D(R) curve (red-solid) and the experimental data. This shows that, if this galaxy behaves as a fractal structure whose dimension D follows the red-solid curve in the top panel, then the resulting NFDG circular velocity curve in the bottom panel (red-solid) will perfectly fit the experimental data, without any need of dark matter. The NFDG D_m(R) curve (blue-dashed) is less effective in fitting the experimental data, but is still a remarkably good fit.

A disk-dominated galaxy, such as NGC 6503, is characterized by a fractional dimension which is very close to D=2. This is due to the axially-symmetric, flattened-disk shape of this galaxy (see also similar galaxies NGC 2841 and NGC 3198). The gas component is less important for this galaxy. See my third, fifth, and seventh papers for a full discussion of this galaxy.