Research

Speaker: Yamini K. Rao

The transfer of mass and energy taking place through the transition region is generally determined by the filling factors. Dere et al. (1987) reported the filling factor to be ranging from 10^-5 to 10^-2 using C IV line. The corresponding path lengths were found to be in the range of 0.1 - 10 km. However, we use density-sensitive lines like O IV and S IV to estimate the electron densities and temperature using high-resolution spectral observations binned to 2” in spatial resolution from the Interface Region Imaging Spectrograph (IRIS). We also devise using new atomic models for the quiet Sun, which include density effects, photo-ionisation, and charge transfer to estimate the path lengths and filling factors. We also conduct studies of centre-to-limb variation of non-thermal velocities. The parametric studies will be useful for interpretation of observations from Solar Orbiter SPICE spectrometer and future TR modelling.