The paper published in the Journal of Geophysical Research (JGR) is titled "BARREL observations of a solar energetic electron and solar energetic proton event", or BARb SEEs SEPs, you gotta have fun with the title right? This current solar cycle has been very quiet, relatively speaking, but during the second BARREL campaign there was the one of the cycle's largest solar energetic particle events. During the solar flare, and/or the propagation of thecoronal mass ejection out through interplanetary space, protons, electrons, and other ions can accelerate to very high energies. When the protons reach our magnetosphere, it presents only a small barrier so many of the protons can enter. But as our magnetic field gets stronger the closer to the planet you are, these protons can only get so far in before they either get lost back out to interplanetary space or to our atmosphere (where BARREL can then infer them!). The solar energetic electrons on the other hand, well, the magnetosphere is a very strong barrier for them. They can only interact with out magnetic field on open field lines, magnetic field lines which are connected to both the Earth and the Sun, a region referred to as the cusp. There is only a very small region where this occurs near both of our magnetic poles.
So why should you care? Well, as a plasma physicist this has some very cool implications. Balloons have not typically been used to study this type of physics, and I believe that no one has used balloons to look at solar energetic electron precipitation to the Earth's atmosphere. Although these types of events are rare, it may give us a new way to study both solar energetic particle events and to map the open closed boundary. This boundary helps define how much energy is transferred from the Sun and solar wind into the magnetosphere. Understanding this input into the magnetosphere has large implications for many areas of space physics.
But what if you are not a plasma physicist, why should you care about this study? These solar energetic particles can affect a lot of space weather, and ultimately terrestrial climate. The most direct space weather implications are of course damage to satellites, disruptions in communication systems, ect. But they also create a lot of greenhouse gasses in the atmosphere. How much of an affect these space weather events have on our climate is still not well understood. As the protons and electrons interact and form different chemicals in our atmosphere, they move around both around the globe as well as changing heights in the atmosphere. Now we're getting way out of my league, my field of science, and having to look at chemistry, something I always try to stay away from. But from my understanding one of the reasons that it's hard to track how these solar energetic particle events affect climate is that the initial event last typically less than a week or so but the ultimate affect on the Earth's temperature may be felt months later. The physical connection from one aspect of the process to the final process is long and involved and probably not completely known. This makes it difficult to calculate and define. We also can't isolate it completely from other events which can create very similar effects. But that's why we keep studying them.
Now I need to get back to work and the next paper!