SSC Seminar Series: "Characterising the Suprathermal Electron PADs"
Wednesday, November 30, 2022 - 3:00pm to 4:00pm
Viewing party in Morse Hall rm 301 OR Zoom
Speaker: Fernando Carcaboso, NASA/Goddard Space Flight Center
Full title: Advantages of Characterising the Suprathermal Electron Pitch-angle Distributions in ICMEs and Long-term Variations
Abstract: Suprathermal electrons (~0.07 — 3 keV at 1AU) are released from the Sun and propagate through the interplanetary medium following the magnetic field lines with a small gyroradius (< 20 km). The shape of their pitch-angle distribution (PAD) encloses valuable information about the large-scale structure of the magnetic field and about the presence, evolution and interaction of transient structures such as interplanetary coronal mass ejections (ICMEs), and stream interaction regions. Using spherical harmonic series, we have characterised the suprathermal electron PAD measured by SWEA onboard STEREO-A, STEREO-B, and SWEPAM onboard ACE. This characterisation allows the automatic identification of different types of distributions (pancake, counterstreaming, loss-cone, strahl, butterfly, isotropic…), analyse the strahl population and its variation with radial distance, orbital position, energy dependence, and even turbulent conditions of the plasma. Some statistical results of the transit of ICME’s bi-directionality and isotropy, as well as solar cycle dependency of these types of PAD and extra applications of the method will be presented.
Schedule: Check out the rest of this season's Space Science Seminar Series, as well as previous recordings.