Absolute magnitude in U, B, V, R, I bands (blue to red, top panel) and mass accretion rate onto the white dwarf Ṁ(R_in) during a dwarf nova outburst. The model parameters are M = 0.6 M_⊙, Ṁ_t = 10¹⁶ g s⁻¹, R_out ≈ 2 × 10¹⁰ cm, i = 0°. The dashed line shows the Ṁ(R_in) reconstructed from the V magnitude light curve assuming Ṁ does not depend on radius. The reconstructed mass transfer rate is 9 × 10¹⁵ g s⁻¹ after averaging over the outburst cycle.