Gabriel Pelouze

Transverse oscillations are observed both in coronal loops (as standing waves) and in open magnetic tubes (as propagating waves).
In coronal loops, standing kink waves can be observed over a large number of periods, without showing any damping.
These decayless kink oscillations are interpreted as the result of a continuous driver at the footpoints of the loop.
However, analytical works predict that kink waves are subject to a cut-off frequency, that results from the atmospheric stratification.
As a result of this cutoff, only high-frequency waves can propagate through the transition region.
Current 3D MHD simulations of standing kink waves only take into account the coronal part of the loop (the driver is located at the top of the transition region), and thus are not sensitive to this cut-off effect.

We present a new numerical setup that allows to study the propagation of a kink wave through the transition region.
A magnetic tube is driven at the base of the chromosphere at different frequency, and we study the propagation of the resulting kink wave through the transition and into the corona.
We compare the resulting behaviour to several analytical formulas that predict the cut-off frequency of kink waves.