The proposal


We aim to set up an International Team with a wide range of expertise in order to summarize current studies of Rossby-type waves in different astrophysical applications and to set up collaboration between the different areas. The expertise of the Team members combines skills in the theory of Rossby waves, numerical simulations, ground- and space- based observations applied to different astrophysical objects (Sun, solar-like stars, astrophysical discs, exoplanets, neutron stars etc.). The proposal intends to discuss three main points. 1) Besides the well-known 11-yr cycle, solar activity undergoes variations over shorter (155-160 days, 1-2 yrs.) and longer (100-1000 yrs.) timescales, which can be explained in terms of Rossby waves (Lou 2000, Zaqarashvili et al. 2010, 2015). Similar “Rossby range” periodicity was detected on solar-like stars by Kepler and CoRoT missions (Lanza et al. 2009, Bonomo and Lanza 2012). Therefore, it is of invaluable importance to discuss the relation between periodicities in activity of Sun and Sun-like stars in terms of Rossby wave theory. 2) Spatial variations of rotation and background plasma parameters (entropy, magnetic field) trigger Rossby-type wave instabilities in astrophysical discs (Lovelace et al. 1999, Umurhan 2010, Lovelace and Romanova 2014) and solar tachocline (Dikpati and Gilman 1999, Zaqarashvili et al. 2010), which are important for angular momentum transport in discs and for magnetic dynamo on the Sun. The proposal will stimulate the exchange of knowledge in both areas. 3) Nonlinear Rossby waves have important influence on large-scale dynamics of planetary atmospheres. The proposal aims to discuss the effect of large-scale magnetic field on nonlinear behavior of Rossby waves in general and on Rossby soliton solution in particular. The main expected outcome of the proposal is to share knowledge and to establish collaboration between the different communities working on Rossby waves in different astrophysical applications.

  • For the full proposal please click the following link. Full proposal