The Cascades

<p><strong>The Field Guide to Particle Physics : Season 2<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><a href="https://pasayten.org/the-field-guide-to-particle-physics/cascades"><strong>The Cascade Particles</strong></a><strong><br></strong><br>Prepare for trouble! And make it double! Today we confront the two Cascade or Xi /ksee/ baryons which each have a PAIR of strange quarks.</p><p>Xi minus checks in with a mass of about 1322 MeV, making it the heaviest baryon we’ve encountered so far. This is just as well, as it comprised of two of those heavier, strange quarks. Together with a third, down quark, it also has a total electric charge of minus 3 thirds or… minus one.</p><p>Xi 0 is just a little bit lighter with a mass of 13 hundred and 14 MeV. Its two strange quarks are paired with an up quark, which gives it an electric charge of twice minus one third PLUS one third, or… zero.</p><p><strong>Decays of the Xi minus</strong></p><p>Like many strange particles, the cascades take quite a while to decay. The Xi minus takes a solid fraction of a nano-second, the usual time it takes to convince one of those strange quarks to decay into an up quark. The result? The strange-strange-down bag of quarks converts to up-strange-down bag, otherwise known as the Lambda 0 baryon.  As usual, that decay is accompanied by some other junk, and in this case the net result is a pi minus.</p><p>As we’ve already seen, the Lambda 0 and the pi minus are both unstable themselves. The former converts to either a proton or a neutron