We have calculated mass-loss rates for a grid of wind models covering a wid
e range of stellar parameters and have derived a mass-loss recipe for two r
anges of effective temperature at either side of the bi-stability jump arou
nd spectral type B1.
For a large sample of O stars, it is shown that there is now good agreement
between these new theoretical mass-loss rates that take multiple scatterin
g into account and observations.
Agreement between the observed and new theoretical wind momenta increases c
onfidence in the possibility to derive distances to luminous stars in dista
nt stellar systems using the Wind momentum Luminosity Relation.
For the winds of the B stars there is an inconsistency in the literature be
tween various mass-loss rate determinations from observations by different
methods. One group of (M) over dot determinations of B stars does follow th
e new theoretical relation, while another group does not. The lack of agree
ment between the observed mass-loss rates derived by different methods may
point to systematic errors in mass-loss determinations from observations fo
r B stars.
We show that our theoretical mass-loss recipe is reliable and recommend it
be used in evolutionary calculations.