Evolution of Turbulent Energy Dissipation at Quasi-perpendicular Fast Interplanetary Shocks: The thickness of shock transition region

We present a comprehensive analysis of the evolution of the turbulent energy dissipation at interplanetary (IP) shocks observed by Parker Solar Probe (≈0.4 AU), Solar Orbiter (≈0.8 AU), and Wind (1 AU). Our previous study reveals the conservation of the energy dissipating mechanisms across different types of IP shocks except fast reverse. Motivated to investigate the thickness of the shock transition region in terms of the dissipation of magnetic field turbulent energy, we adopt pairs of quasi-perpendicular fast forward (FF) and reverse (FR) shocks observed at Parker Solar Probe, Solar Orbiter, and Wind. By comparing these pairs of shock, we anticipate examining (1) whether FF and FR shocks are systematically different, (2) the dependence of the shock transition thickness on critical Mach number, and (3) on heliocentric distance. We present several parameters, i.e., cross- and magnetic helicity, and the amplitude of magnetic field fluctuations for the estimation of their correlation with the spectral index evolving through shock. The abrupt changes of the plasma parameters along with the spectral index shorter than the temporal resolution of the plasma measurement are overall observed showing their minimal correlations. This suggests a role of IP shock as a thin boundary simply distinguishing two different plasmas. We will extend this hypothesis toward a statistical study including near-shock processes such as particle acceleration and wave activities.