Vol. 538
In section 9. The Sun

The interplanetary magnetic structure that guides solar relativistic particles

High-energy particles originating from the Sun led to a nuclear cascade in the Earth atmosphere that can finally be detected by a neutron monitor on the ground. By studying the timing of enhancements detected by the neutron monitors, the authors were able to connect time delays to the spatial structure of (interplanetary) coronal mass ejections. This indicates that these coronal mass ejections exhibit 'wound-up' magnetic fields leading to longer path lengths, hence longer travel times for the energetic particles from the Sun.