Authors: Qiang Hu (UAH)
Interplanetary coronal mass ejections (ICMEs) are large-scale structures in the solar wind, corresponding to the counterparts of CMEs when they propagate into the interplanetary space. They are generally characterized by a set of observational signatures based on in-situ spacecraft measurements when intercepted, typically at one location in space, and over a time period of days. For decades, the effort of examining the magnetic field topology of ICMEs based on single-point in-situ spacecraft measurements has been ongoing, typically by model-based fitting approach with significant amount of uncertainty, owing to the variability in the underlying magnetic field configuration of (I)CMEs. The limitations in the models and their outputs are increasingly realized and remedies are sought, especially by using multiple in-situ spacecraft measurements, simultaneously taken when one ICME structure is crossed by two or more observing spacecraft. We intend to present such an approach based on an analytic model for the magnetic structure of ICMEs or magnetic clouds, through an event study when an ICME structure crossed two (and possibly three) spacecraft near Earth. In particular, we aim to address or stimulate discussions concerning the following questions:
- What’s the appropriate way of performing model fitting to in-situ spacecraft measurements along one or multiple spacecraft paths?
- How are model assumptions justified through various data analysis methods?
- Is validation through a correlative analysis of model results by employing multiple (>=2) in-situ spacecraft datasets sufficient?
In the end, we discuss the connections of in-situ modeling results of ICMEs to global numerical simulations and the properties of the CME origination on the Sun.