The thick dashed line represents the estimate for the uncovered disk. The thick solid line shows the same for the disk with undoped cap. The thin solid line represents the qualitative estimate formula_29 without coefficients. Circles corresponds to the experimental data for the power achieved and corresponding estimates for the background loss formula_21. All future experiments and numerical simulations and estimates are expected to give values of formula_31, that are below the red dashed line in Fig.5 for the uncovered disks, and below the blue curve for the disks with anti-ASE cap. This can be interpreted as a scaling law for disk lasers