Direct First PSP Observation Of The Interaction Of Two Successive Interplanetary Coronal Mass Ejections On November 2020

It is well established that Interplanetary Coronal Mass Ejections (ICMEs) and their associated structures may unleash the most harmful geomagnetic storms at Earth and other undesired space weather effects at man-made spacecraft. Unfortunately, little is known about their internal magnetic structure due to limitations imposed by currently-available measurements and techniques. Added to this is the fact that they are subject to intrinsic and extrinsic evolution throughout their journey from the Sun to Earth and other objects. Here, we investigate the effects of the evolutionary processes in the internal magnetic structure of two ICMEs detected in-situ during the 29 November and 1 December 2020 by PSP. The sources of the ICMEs were observed remotely at the Sun in EUV and subsequently tracked to their coronal counterparts in white light. This period is of particular interest to the community since it has been identified as the first widespread solar energetic particle event solar cycle 25. The distribution of various solar and heliospheric-dedicated spacecraft throughout the inner heliosphere during Parker Solar Probe (PSP) observations of these large-scale magnetic structures enables a comprehensive analysis of the internal evolution and topology of such structures. By assembling different models, techniques and areas of expertise, we identify the signatures of interaction between the two consecutive ICMEs and the implications for their internal structure. We use multispacecraft observations in combination with a remote-sensing forward modeling technique, numerical propagation models and in-situ reconstruction techniques. Full reconciliation among these methods provides a full understanding of the events. The outcome demonstrates that both origin CMEs are interacting in the vicinity of PSP. Thus, we identify the in-situ observations based on the physical processes that are associated with the interaction and collision of both CMEs. We also expand the flux rope modeling and in-situ reconstruction technique to incorporate the aging and expansion effects in a distorted internal magnetic structure of the explore the implications of both effects in the magnetic configuration of the ICMEs.