Dr. Norbert Jakowski and Dr. Mohammed Mainul Hoque from the DLR Institute of Communications and Navigation
In this latest study, peak electron density data from three low earth orbiting satellite missions, as well as total electron content data obtained from numerous global navigation satellite system ground stations, have been used to develop a global model of ionospheric equivalent slab thickness, known as the (Neustrelitz equivalent Slab Thickness Model – NSTM). The equivalent slab thickness of the ionosphere characterizes the width of vertical electron density profiles and is an important parameter for a better understanding of ionospheric processes under regular and disturbed conditions. The model description focuses on an overall view of the behaviour of the equivalent slab thickness as a function of local time, season, geographic/geomagnetic location and solar activity on a global scale. The model agrees quite well with the overall observation data within a RMS range of 70 km.
New study finds that electrons can reach ultra-relativistic energies for very special conditions in the magnetosphere when space is devoid of plasma
Dr. Hayley Allison, Prof. Dr. Yuri Shprits, Dr. Irina Zhelavskaya, Dr. Dedong Wang, Artem Smirnov from GFZ Potsdam
Simultaneous observations of plasma waves allow for the routine inference of total plasma number density, a parameter that is very difficult to measure directly. On the basis of long-term observations in 2015, this study shows that the underlying plasma density has a controlling effect over acceleration to ultrarelativistic energies, which occurs only when the plasma number density drops down to very low values (~10 cm–3). Such low density creates preferential conditions for local diffusive acceleration of electrons from hundreds of kilo–electron volts up to >7 MeV.