Diagnostics of turbulent corona using transverse Alfvénic waves

In the last decade, Alfvénic fluctuations remained a major focus of research on coronal heating and the origin of solar wind. Theoretical studies postulated that predominantly outward propagating waves carry a significant fraction of energy and momentum from the lower solar atmosphere and dissipate in corona, via MHD turbulence, thereby heating the plasma and accelerating the solar wind. In this presentation, I will discuss some basic observational characteristics of these waves in the corona, their diagnostic capabilities to infer magnetic fields and associated energy injection scales. These transverse scales, also known as perpendicular correlation length(s) is a key parameter of Alfvénic turbulence driven models where it strongly influences the energy dissipation below and above the sonic point, while affecting the solar wind acceleration profiles in the solar corona and beyond. I will compare the estimates of perpendicular correlation lengths at the base of solar corona with those obtained from in-situ measurements and numerical models. Finally, I will highlight how the inhomogeneous nature of lower and middle corona can affect the observed wave energy injection scales that needs to be accounted for in future numerical Alfvén wave turbulence studies.