Density-magnetic field correlation studies for characterizing the turbulence content in the SSX plasma

Turbulence is of great interest in magnetized plasmas and can be determined by carrying out a frequency power spectrum in the fluctuations present in the turbulent quantities. However, the power spectrum does not shed light on the underlying physical mechanisms at play. To address this issue, one may consider the turbulent fluctuations as primarily originating from the non-linear interaction of linear MHD modes. This type of analysis has been used in solar wind turbulence observations to determine the proportion of fast and slow wave content in the turbulent plasma¹. The different wave modes can be distinguished by determining the correlation between the fluctuations in the density and the co-located magnetic field aligned component. In this poster, we will present the preliminary results obtained by carrying out the correlation analysis on the fluctuations present in the density and the co-located magnetic field. These studies are carried out on the SSX device, where we generate a spheromak which then tilts and relaxes to a twisted structure. The relaxation process is highly turbulent in nature and in this phase, the plasma is used for carrying out these studies.

¹Howes et. al., Ap. J. Lett. 753, L19 (2013).