The University of Southampton
University of Southampton Institutional Repository

The impact of an ICME on the Jovian X-ray aurora

Dunn, William R., Branduardi-Raymont, Graziella, Elsner, Ronald F., Vogt, Marissa F., Lamy, Laurent, Ford, Peter G., Coates, Andrew J., Gladstone, G. Randall, Jackman, Caitriona M., Nichols, Jonathan D., Rae, I. Jonathan, Varsani, Ali, Kimura, Tomoki, Hansen, Kenneth C. and Jasinski, Jamie M. (2016) The impact of an ICME on the Jovian X-ray aurora Journal of Geophysical Research: Space Physics, 121, (3), pp. 2274-2307. (doi:10.1002/2015JA021888).

Record type: Article


We report the first Jupiter X-ray observations planned to coincide with an interplanetary coronal mass ejection (ICME). At the predicted ICME arrival time, we observed a factor of ?8 enhancement in Jupiter's X-ray aurora. Within 1.5 h of this enhancement, intense bursts of non-Io decametric radio emission occurred. Spatial, spectral, and temporal characteristics also varied between ICME arrival and another X-ray observation two days later. Gladstone et al. (2002) discovered the polar X-ray hot spot and found it pulsed with 45 min quasiperiodicity. During the ICME arrival, the hot spot expanded and exhibited two periods: 26 min periodicity from sulfur ions and 12 min periodicity from a mixture of carbon/sulfur and oxygen ions. After the ICME, the dominant period became 42 min. By comparing Vogt et al. (2011) Jovian mapping models with spectral analysis, we found that during ICME arrival at least two distinct ion populations, from Jupiter's dayside, produced the X-ray aurora. Auroras mapping to magnetospheric field lines between 50 and 70 RJ were dominated by emission from precipitating sulfur ions (S7+,…,14+). Emissions mapping to closed field lines between 70 and 120 RJ and to open field lines were generated by a mixture of precipitating oxygen (O7+,8+) and sulfur/carbon ions, possibly implying some solar wind precipitation. We suggest that the best explanation for the X-ray hot spot is pulsed dayside reconnection perturbing magnetospheric downward currents, as proposed by Bunce et al. (2004). The auroral enhancement has different spectral, spatial, and temporal characteristics to the hot spot. By analyzing these characteristics and coincident radio emissions, we propose that the enhancement is driven directly by the ICME through Jovian magnetosphere compression and/or a large-scale dayside reconnection event.

PDF - Accepted Manuscript
Restricted to Repository staff only
Download (25MB)
PDF jgra52419.pdf - Version of Record
Available under License Creative Commons Attribution.
Download (16MB)

More information

Accepted/In Press date: 27 January 2016
e-pub ahead of print date: 29 January 2016
Published date: March 2016
Organisations: Theoretical Partical Physics Group


Local EPrints ID: 397616
ISSN: 2169-9380
PURE UUID: 5d734bee-97d5-4fed-a41c-a3011fe72146

Catalogue record

Date deposited: 04 Jul 2016 13:14
Last modified: 17 Jul 2017 18:37

Export record



Author: William R. Dunn
Author: Graziella Branduardi-Raymont
Author: Ronald F. Elsner
Author: Marissa F. Vogt
Author: Laurent Lamy
Author: Peter G. Ford
Author: Andrew J. Coates
Author: G. Randall Gladstone
Author: Caitriona M. Jackman
Author: Jonathan D. Nichols
Author: I. Jonathan Rae
Author: Ali Varsani
Author: Tomoki Kimura
Author: Kenneth C. Hansen
Author: Jamie M. Jasinski

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton:

ePrints Soton supports OAI 2.0 with a base URL of

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.