Ionospheric plasma collision frequency from in-situ measurements of the STORMS sounding rocket mission

The ionospheric plasma environment exhibits several instabilities, including gradient drift instability (GDI), Kelvin–Helmholtz instability (KHI), Perkins Instability, and Rayleigh–Taylor instability (RTI). Ionospheric irregularities generated from these instabilities produce scintillations in the ionospheric plasma which can disrupt RF signals utilized in satellite and GNSS communication systems. The electrodynamic characteristics of these ionospheric plasma instabilities are mostly influenced by ion-neutral collision frequency, electron density, and density gradients. In this work, we analyze the in-situ measurements obtained from sweeping impedance probe (SIP) onboard the Tropical STORMS, sounding rocket launched from Wallops Island, Virginia on 30 October 2007. The objective of this mission was to investigate the dynamics of mid-latitude spread F (MSF) event impacted by the tropical storm, Noel. In previous research, anomalies have been observed while extracting plasma parameters from SIP measurements that exhibited deviations from the standard cold plasma fluid theory and investigation have been conducted to explain these observed discrepancies. This study develops an analytical model implementing STORM’s SIP data to extract altitude profiles of electron-neutral collision frequency. In addition, Global Ionosphere-Thermosphere Model (GITM) is utilized to calculate altitude profiles of ion-neutral collision frequency from empirical models. By comparing collision frequency profiles generated from in-situ measurements and GITM data, we develop a relationship between electron-neutral and ion-neutral collision frequencies to explore their significance on ionospheric instability growth rates during the period of MSF events.