How do scientists know that the particles revealed after a proton or lead ion collision are different from each other, such as quarks and muons, and not just smaller pieces of protons or lead ions? (If I were to smash two lead bullets together, they would break into smaller pieces, but they would still be lead.)
David Kennedy, Aburndale, Florida
Published: Monday, April 22, 2013
When particle accelerators collide protons or lead ions, they do so within special sections of an instrument that can capture fine details. These huge detectors are like giant digital cameras that take photographs of the outcome of each collision. (Researchers keep only a subset of these photographs, but that is another story.) These pictures record information about each outgoing particle produced in the collision.
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