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I'm doing a paper on quarks and I'm investigating the discovery of top quark. I have a question on the matter. When you talk about of "jets" of particles, what are you meaning? Lots of particles? Probably is an idiomatic problem because english it is not my mother tongue. Thank you.

Alejandro Nieto González ETSIT- Universidad Politécnica de Madrid. Spain.

Hi Alejandro,

When two particles for example a proton and an antiproton collide at high energies many particles are produced.

For example the top quark can be produced from an antiquark and a quark colliding. The top quark cannot exist on its own for very long it decays into a W boson and a b quark. The W boson decays further into quarks or leptons. Individual quarks don't exist very long by themselves due to conservation of color. They must combine with other quarks to become color neutral. This combination produces mesons (particle made of two quarks) or hadrons (particle made with three quarks), these particles decay through various decay modes producing a flood of particles that are read out as jets in our detectoror. If you look at a display of an event this energy radiates outward like jets.

Please look at
http://www.fnal.gov/pub/inquiring/physics/discoveries/top_quark_background/t op95_how_do_we_know.html

I hope this helps, don't hesitate to ask more questions,
Christina Hebert
Graduate Student University of Kansas

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