Thermal equilibrium (ṁ–Σ) diagram for R = 30 M. Solutions based on different assumptions are compared. Black lines show analytical S-curves for Keplerian motion in the Paczyński-Wiita potential with ξ = 1 and α = 1;0.1;0.01;0.001 (left to right). Red dots represent stationary numerical slim discs for different accretion rates, with α = 0.01 (Sect. 3). Blue crosses correspond to GRRMHD simulations (see Table 1 and Sect. 4). All solutions have M = 10 M_⊙.