Based on a database, a number of conclusions are derived concerning the
power flow into the divertor region of the ASDEX tokamak. The non-transition to
detachment in ASDEX is investigated with respect to the sputtering of the copper
divertor plates. Following the definition of the low- and high-recycling regions, the
best fittings of the power widths in front of the divertor plates are extracted for
Ohmic (OH) or neutral-beam-injection heating in low-confinement mode (NBI, L-mode)
shots. On the basis of these fittings, it is concluded that the safety factor q
and the electron temperature in the divertor can be considered as the main robust
parameters. In contrast, the peak of the power inserted into the divertor does not
behave as a robust parameter, thus introducing the problem of colinearities.