Time evolution of the average magnetic field strength (left panel) and the normalized Maxwell stress (right panel) for the no feedback runs. Blue lines represent simulations with an initial vertical field and the red lines represent simulations with an initial toroidal field. Darker colors represent higher Jeans floor (N_J = (4, 8, 10, 16)). The N_J = 4 and N_J = 8 simulations have a rapid amplification in the magnetic field early on due to spiral arm compression. We can see that we get the strongest α_MW exhibited during the growth phase of the N_J = 8 cases, correlating to the generation of radial and toroidal fields during the dynamo process. The elevated level in α_MW for all the cases with an initial toroidal field is simply due to the initial field and normalization (B_z ≈ 0).