A Catalog of Interplanetary Coronal Mass Ejections Observed by Juno between 1 and 5.4 AU

Autor: Emma E. Davies, Robert J. Forsyth, Réka M. Winslow, Christian Möstl, Noé Lugaz
Rok vydání: 2021
Předmět:
DOI: 10.48550/arxiv.2111.11336
Popis: We use magnetic field measurements by the Juno spacecraft to catalog and investigate interplanetary coronal mass ejections (ICMEs) beyond 1 AU. During its cruise phase, Juno spent about 5 years in the solar wind between 2011 September and 2016 June, providing measurements of the interplanetary magnetic field (IMF) between 1 and 5.4 AU. Juno therefore presents the most recent opportunity for a statistical analysis of ICME properties beyond 1 AU since the Ulysses mission (1990-2009). Our catalog includes 80 such ICME events, 32 of which contain associated flux-rope-like structures. We find that the dependency of the mean magnetic field strength of the magnetic flux ropes decreases with heliocentric distance as $r^{-1.24 \pm 0.43}$ between 1 and 5.4 AU, in good agreement with previous relationships calculated using ICME catalogs at Ulysses. We combine the Juno catalog with the HELCATS catalog to create a dataset of ICMEs covering 0.3-5.4 AU. Using a linear regression model to fit the combined dataset on a double-logarithmic plot, we find that there is a clear difference between global expansion rates for ICMEs observed at lesser heliocentric distances and those observed farther out beyond 1 AU. The cataloged ICMEs at Juno present a good basis for future multispacecraft studies of ICME evolution between the inner heliosphere, 1 AU, and beyond.
Comment: Table 1 is available in its entirety in machine-readable format. Please contact the corresponding author if you wish to use the database
Databáze: OpenAIRE