The Strange Quark

<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><strong>Strange Quarks</strong><br>Quarks make up baryons like the <a href="https://pasayten.org/the-field-guide-to-particle-physics/proton">proton</a> and the <a href="https://pasayten.org/the-field-guide-to-particle-physics/neutron">neutron</a>. Or more exotic things like the <a href="https://pasayten.org/the-field-guide-to-particle-physics/lambda-zero">Lambda0</a> or the <a href="https://pasayten.org/the-field-guide-to-particle-physics/delta-baryons">Delta++</a>. Previously, we’ve learned about the <a href="https://pasayten.org/the-field-guide-to-particle-physics/up-and-down-quarks">up and down quarks</a> - those fundamental constituents of matter like protons and neutrons. Today we’re learning about the third of the three light quarks - the strange quark!</p><p>The stability of quarks against decay is a quirky thing to talk about because the context matters a lot. One of the down quarks in the neutron will decay - in about fifteen minutes or so - to an up quark, shooting out an electron and leaving behind a proton. But that’s only if the neutron is alone. If its bound together with a proton in an <a href="https://pasayten.org/the-field-guide-to-particle-physics/nucleus">atomic nucleus</a>, it is stable.</p><p>The strange quark will also decay - also typically to an up quark - and it’s lifetime also depends on the context. The Lambda baryon - like the proton - is a big bag of nuclear goo with three qu