Principle
In DONUT, protons accelerated by the Tevatron were used to produce tau neutrinos via decay of charmed mesons. After eliminating as many unwanted background particles as possible by a system of magnets and bulk matter (mostly iron and concrete), the beam passed through several sheets of nuclear emulsion. In very rare cases one of the neutrinos would interact in the detector, producing electrically charged particles which left visible tracks in the emulsion and could be electronically registered by a system of scintillators and drift chambers.
Using the electronic information, possible neutrino interactions were identified and selected for further analysis. This meant photographically developing the emulsion sheets so any traces left by particles passing through them would show up as a small black dot. By connecting these dots across subsequent sheets, the path that each particle had taken was reconstructed and likely neutrino interactions identified. The characteristic properties of tau neutrino interactions were that several tracks suddenly appeared without any leading up to them and that one of those tracks would show a "kink" after a few millimeters, indicating decay of a tau lepton.
Read more about this topic: DONUT
Famous quotes containing the word principle:
“No two men see the world exactly alike, and different temperaments will apply in different ways a principle that they both acknowledge. The same man will, indeed, often see and judge the same things differently on different occasions: early convictions must give way to more mature ones. Nevertheless, may not the opinions that a man holds and expresses withstand all trials, if he only remains true to himself and others?”
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