The use of wavelets to determine parameters of flaring loops (and other physical processes) | Javier Lopez Santiago (UCM – Madrid, Spain )

Since the past decade, the knowledge of high-energy processes in stars has experienced large advance. However, there are still some issues about physical processes taking place in stars that remain uncertain and need a more accurate study. In particular, to deep into some aspects of X-ray coronal emission, we need new observational methods and/or new instrumentation. An example of it is the poor constraints done to physical parameters of flaring loops in solar-type stars. Several theoretical and observational studies have been carried out but there is still controversy of some particular results, including the geometry of the magnetic field and the loop’s length. On the one hand, some authors believe that flaring processes in late-type stars are scaled-up versions of those taking place in the Sun and that the geometrical aspect of loops must be similar in both cases. The models used by these authors to obtain parameters from the observation of flares are so-called scaling laws. This scenario predicts stronger magnetic fields in stars than in the Sun in many cases. On the other hand, other models are based on physical laws and assume aspect rations of the flaring loops similar to that of the Sun, obtaining much longer loop lengths and magnetic fields with values more similar to those observed for the Sun. To distinguish between both scenarios, we need to use independent methods that allow us to determine the same parameters for the flare. A powerful technique to determine some parameters of the flaring loop is the wavelet analysis of light curves. I present a preliminary study of this technique using Montecarlo analysis and apply it to several stars.