The Positron Excess

<p><strong>The Field Guide to Particle Physics : Season 3<br></strong><a href="https://pasayten.org/the-field-guide-to-particle-physics">https://pasayten.org/the-field-guide-to-particle-physics</a><br>©2022 The Pasayten Institute <a href="https://creativecommons.org/licenses/by-sa/4.0/">cc by-sa-4.0</a><br>The definitive resource for all data in particle physics is the Particle Data Group: <a href="https://pdg.lbl.gov/">https://pdg.lbl.gov</a>.</p><p>The Pasayten Institute is on a mission to build and share physics knowledge, without barriers! <a href="http://pasayten.org/heysean">Get in touch</a>.</p><p><br><strong>The Positron Excess</strong></p><p>Space is not a safe place. Matter and energy take on a totally different form than is familiar from our planetary lifestyle. Radiation is everywhere, and with it we find high energy particles flying all over the place. One of the biggest challenges in a voyage to Mars is shielding the travelers from all that radiation. Our magnetosphere and atmosphere do an outstanding job of filtering out the most of the high energy particles flying at us from all directions.</p><p>Many energetic particles come from the sun. Fast moving protons and electrons that boil off our friendly plasma ball get trapped in the <a href="https://en.wikipedia.org/wiki/Van_Allen_radiation_belt">van Allen belts</a> of our earth’s magnetic field. Way above the atmosphere, we can see them sometimes as the Aurora.</p><p>Other energetic particles come to us from inside the Milky Way galaxy. <a href="https://www.energy.gov/science/doe-explainssupernovae">Exploding stars</a>, <a href="https://imagine.gsfc.nasa.gov/science/objects/neutron_stars1.html">neutron stars</a> and other monsterous astrophysical objects can shed or accelerate their own high energy particles. Often these particles have more energy than those put off by the sun, but it’s the same story: A lot of protons, a few electrons, and also some heavier nuclei: like alpha particles. Much less often, we see cosmic rays made up of even b