  New measurements of jet quenching observables at RHIC and at the LHC, such as
jet substructure observables, demand an increased precision in the theory
calculations describing medium-induced radiation of gluons. Closed expressions
for the gluon spectrum including a full resummation of multiple scatterings
have been known for the past 20 years. Still they have only been evaluated in
specific limits either taking a few terms in an opacity expansion or by
employing a Gaussian approximation for the interaction potential -- which
misses essential physical effects. We present here a new flexible method to
compute the full spectrum for a realistic interaction potential, thus allowing
us for the first time to properly quantify the effect of the all-order
resummation of multiple scatterings. This new approach paves the way for
precision phenomenological studies including multiple scattering effects such
as coherence phenomena.
