Modelling the magnetic vectors of ICMEs detected by radially aligned multiple spacecraft using INFROS
Abstract
Interplanetary flux rope simulator (INFROS) is an observationally constrained analytical model dedicated for forecasting the strength of southward component (Bz) of magnetic field embedded in interplanetary coronal mass ejections (ICMEs). In this work, we validate the model for six ICME events which were sequentially observed by the radially aligned multiple spacecraft at two different heliocentric distances. The six selected ICME events in this study comprise of cases associated with isolated CME evolution as well as the adverse heliospheric conditions that include the interaction of the ICMEs with the high-speed streams (HSS) and high- density streams (HDS). For the isolated CMEs, our results show that the model outputs at both the spacecraft are in remarkably good agreement with the in-situ observations. However, for the interacting events, the model could capture the CME evolution at the first spacecraft until the interaction occurs and subsequently under-estimate the field strength at the second spacecraft as the ICME evolution ceases to be self-similar due to its interaction with the HSS and HDS. Our results show that INFROS can be used as an efficient tool to forecast the magnetic vectors of ICMEs for the cases of isolated CMEs. This work also presents a quantitative estimation of the enhanced field strength of the ICMEs due to interaction which may lead to severe space weather conditions. We conclude that the assumption of self-similar expansion provides the lower limit for the magnetic field strength estimated at any heliocentric distance, based on the remote sensing observations.
- Publication:
-
44th COSPAR Scientific Assembly. Held 16-24 July
- Pub Date:
- July 2022
- Bibcode:
- 2022cosp...44.2434S