Large Electron–Positron Collider

<p>The Large Electron–Positron Collider  (LEP) was one of the largest <a href="/facts/Particle_accelerator/Pkuc08xC">particle accelerators</a> ever constructed. It was built at <a href="/facts/CERN/y1gwRchm">CERN</a>, a multi-national centre for research in nuclear and particle physics near <a href="/facts/Geneva/14gXxjcq">Geneva</a>, Switzerland. 
</p><p>LEP collided <a href="/facts/Electron/L0KBo5cW">electrons</a> with <a href="/facts/Positron/HgV4zBzA">positrons</a> at energies that reached 209 GeV. It was a circular collider with a <a href="/facts/Circumference/r1rntU0f">circumference</a> of 27 kilometres built in a tunnel roughly 100 m (300 ft) underground and passing through <a href="/facts/Switzerland/LcGuxeTe">Switzerland</a> and <a href="/facts/France/CxIeIKM3">France</a>. LEP was used from 1989 until 2000. Around 2001 it was dismantled to make way for the <a href="/facts/Large_Hadron_Collider/XWJCFSqT">Large Hadron Collider</a>, which re-used the LEP tunnel. To date, LEP is the most powerful accelerator of <a href="/facts/Lepton/X4a6MGop">leptons</a> ever built.
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Large Electron–Positron Collider open-in-new

Large Electron–Positron Collider