Skip Ribbon Commands
Skip to main content
TLEP is a high luminosity circular e+e- collider to study the Higgs Boson and physics at the electroweak scale
It is a first step in a possible long term vision for CERN
Welcome to the web pages of the TLEP design study group!
TLEP: A design study of high-luminosity e+e− circular colliders for precise measurements of the Higgs-like H(126) boson properties and precision physics at the electroweak scale
 Read/comment/sign the draft design study proposal
LEP3 is an e+e- circular collider with a centre-of-mass energy of up to 240GeV. It is an old idea recently revived after the discovery of H(126), a standard model Higgs-like object within the reach of circular colliders.  One published account of the idea can be found in arXiv:1112.2518v2 [hep-ex]. A more up-to-date document can be found in the European Strategy Preparatory Group page here. The sister paper dealing with physics studies can be found hereTLEP (for tripple LEP) is the evolution of the idea in a bigger, 80-km tunnel (a possible location can be seen above right) which can eventually house a very high energy proton collider. It can reach energies up to 350GeV.

TLEP has enormous potential for accurate Higgs measurements, as well as measurements of unprecedented precision at the Z peak and the WW threshold. Its physics programme can pave the way towards the discovery of physics beyond the standard model by testing the closure of the standard model with a precision not available at other machines. It is an ambitious project which nevertheless relies on the evolution of proven technology. LEP3 is a much more modest project which however has a much lower cost due to extensive use of the existing LHC infrastructure, including the two main experiments ATLAS and CMS. It can start after the completion of the LHC programme.  
Our initial studies show that circular colliders of this size offer a series of advantages over linear machines: Higher luminosity, better reliability, many interaction points, a richer electroweak programme, better experimental environment, and lower cost. No showstoppers have been identified. Since such machines would be "burning up" beams so efficiently (beam lifetimes due to physics processes is a few minutes) a top-up scheme is envisaged (above right)
We consider the concept to be highly interesting and deserving a detailed study. Depending on what is discovered at the LHC when it runs close to its design energy, LEP3/TLEP might provide a very attractive alternative to other projects for the medium term (twenties to thirties).

(provisional logo)


Roy Aleksan

Alain Blondel

Patrick Janot

Frank Zimmermann

Marco Zanetti

John Ellis

Mike Koratzinos

 For comments and suggestions please contact