A joint Fermilab/SLAC publication

Jets

11/01/07

Jets are sprays of particles that fly out from certain high-energy collisions—for instance, from violent collisions of protons and antiprotons at Fermilab’s Tevatron accelerator, or in the similar proton-proton collisions that will take place at CERN’s Large Hadron Collider.

Explain it in 60 seconds: Jets
 

drawing
“When you’re a jet, you’re a jet all the way, from your first gluon split to your last K decay...”
Illustration: Sandbox Studio

Jets are sprays of particles that fly out from certain high-energy collisions—for instance, from violent collisions of protons and antiprotons at Fermilab’s Tevatron accelerator, or in the similar proton-proton collisions that will take place at CERN’s Large Hadron Collider.

These collisions create very energetic quarks and gluons; as they travel away from the collision point, they emit more gluons, which can split into even more gluons. This results in a relatively narrow cascade, or jet, of particles.

In the last stage of jet creation, quarks and gluons combine to form particles such as protons, pions, and kaons. By measuring these end products, physicists can determine the properties of a jet, and thus the details of the collision that produced it. Scientists expect to see jets in the signatures of almost every interesting collision at the Large Hadron Collider.

The most violent collisions will produce jets with the highest momentum, and these can be used to probe the smallest distances within the colliding protons, less than one-billionth of a billionth of a meter. Physicists hope they can use these most energetic jets to look inside the quarks that make up protons.

Joey Huston, Michigan State University

 
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