Enclosed mass (3D spherical, top), circular velocity (middle), and dark matter (bottom) profiles for different components of an example galaxy as a function of projected major axis radius, for bulge-to-total ratios of B/T = 0, 0.25, 0.5, 0.75, 1 (left to right). For all cases, we compute the mass components assuming values for a typical z = 2 massive main-sequence galaxy with log₁₀(M_*/M_⊙) = 10.5: M_bar = 6.6 × 10¹⁰ M_⊙, R_e, disk = 3.4 kpc, n_disk = 1, q_0, disk = 0.25, R_e, bulge = 1 kpc, n_bulge = 4, q_0, bulge = 1, and a NFW halo with M_halo = 8.9 × 10¹¹ M_⊙ and c = 4.2. Shown are the M_sph(< r = R) and v_circ(R) profiles for the disk (dashed blue), bulge (dash-dotted red), total baryons (disk+bulge; dash-dot-dot green), halo (dotted purple), and composite total system (solid black). Vertical lines mark R = R_e, disk (solid grey) and the 3D spherical half-mass radii r_{1/2, mass, 3D} for the disk (dashed blue), bulge (dash-dotted red), and total baryons (dash-dot-dot green). Two dark matter fraction definitions are shown in the bottom panels, and , with long dashed grey and long dash-triple-dotted dark grey lines, respectively. We note that the and curves are also shown in the top and middle panels, respectively, with the scale at the right axis of each panel. When a disk component is present, the system is no longer spherically symmetric, so M_DM, sph/M_tot, sph and differ. This deviation is larger when the disk contribution is large (i.e., lower B/T), although even at low B/T the difference is relatively modest (see also Fig. 6). Additionally, while the ratio r_{1/2, mass, 3D}/R_e for a single component (e.g., the disk or bulge) is generally modest (see Fig. 2), for a composite disk+bulge system, the total baryon r_{1/2, 3D, baryon} becomes much smaller relative to R_e, disk with increasing B/T (vertical green dash-dot-dot and solid grey lines). If such disparate “half” radii definitions are used to define f_DM apertures (i.e., versus , horizontal solid grey and green dash-dot-dot lines), this leads to increasingly large offsets between the f_DM values towards higher B/T (see also Fig. 7).