  We investigate a single vortex reconnection event in superfluid helium at
finite temperatures using the vortex filament model. The reconnection induces
Kelvin waves which strongly increase energy dissipation. We evaluate the mutual
friction dissipation from the reconnection and show that the dissipation power
has universal form, which is seen by scaling both time (measured from the
reconnection event) and power by the mutual friction parameter alpha. This
observation allows us to conclude that the Kelvin-wave cascade is not important
in the energy dissipation process within the range alpha > 0.001. Rather, the
energy is directly transferred from Kelvin waves to the normal component.
Moreover, while the excited Kelvin waves greatly enhance energy dissipation, no
similar change is seen in angular momentum from the reconnection event. This
result has similarities with recent 3He-B measurements. Our results also
confirm another earlier observation that the minimum distance between vortices
scales approximately as d ~ sqrt(|t-trec|), both before and after the
reconnection event.
