FDG RESULTS FOR NGC 6674

NGC 6674 is a barred spiral galaxy in the constellation Hercules. This galaxy also has a strong central bulge component and a dominant stellar disk at larger distances. NFDG results for NGC 6674 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 decrease from D=3.0 at smaller radial distances to D=2.3-2.4 at larger distances. This is typical NFDG behavior for galactic structures dominated by a spherically-symmetric component, such as the galactic bulge. 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 still a remarkably good fit.

A bulge-dominated galaxy, such as NGC 6674, is characterized by a fractional dimension which is larger than the D=2 value that we observed for a disk-dominated galaxy, such as NGC 6503. This is due to the spherical symmetry of the dominating bulge component (see also similar galaxies in the NFDG catalog). The gas component is even less important in this case. See my fifth paper for a full discussion of this galaxy.