Large Electron-Positron Collider
The Large Electron–Positron Collider (LEP) was one of the largest particle accelerators ever constructed. It was built at CERN, a multi-national centre for research in nuclear and particle physics near Geneva, Switzerland.
LEP collided electrons with positrons at energies that reached 209 GeV. It was a circular collider with a circumference of 27 kilometres built in a tunnel roughly 100 m underground and passing through Switzerland and France. LEP was used from 1989 until 2000. Around 2001 it was dismantled to make way for the Large Hadron Collider, which re-used the LEP tunnel. To date, LEP is the most powerful accelerator of leptons ever built.
Design
The original feasibility study was published in 1976.[1] The LEP designs, as the project evolved, were subsequently presented in the so-called Blue, Pink and Green books.
LEP2
The LEP2 programme was launched in August 1989, immediately after the running-in of LEP at 46 GeV per beam. Following the successful research and development programme on superconducting (SC) accelerating cavities which began in 1979, the initial LEP2 programme foresaw the installation of 192 SC cavities in addition to the original 128 ambient-temperature copper accelerating cavities. The aim was to achieve an operational beam energy of 87 GeV, with an expected peak luminosity of about 4 × 10³¹ cm⁻² s⁻¹. In order to fully exploit the physics potential of LEP, and thanks to the steady improvement both in our understanding of the machine and in machine performance, the scope of the LEP2 programme was progressively widened to enable an increase in operational energy from 87 GeV in 1996 to 96 GeV by 1998—with an expected maximum peak luminosity of about 1.4 × 10³² cm⁻² s⁻¹.[2]
Project leaders
In 1980 Herwig Schopper announced that Emilio Picasso would lead the LEP project once it was approved,[3] Emilio held this post through the construction, and initial operation of LEP 1 until he left CERN in 1992.[4] In 1990 Carlo Wyss became deputy to the LEP 200 project leader, Günther Plass, who was the Director for Accelerators at the time.[5] Wyss was appointed LEP 200 project leader by Carlo Rubbia in January 1991, a position he held until Stephen Myers took over in April 1996.[6][7][8][9] Myers led the project until its end in year 2000.[7]
References
- ↑ Physics with very high-energy e+e− colliding beams, CERN-76-18, doi:10.5170/CERN-1976-018.
- ↑ LEP design report, v.3 : LEP2 , Geneva : CERN, 1996, http://dx.doi.org/10.17181/CERN.HAIW.7L49.
- ↑ 66th Session of Council, 26 - 27 Jun 1980 - CERN, Geneva, Switzerland, CERN/1377/Draft, https://cds.cern.ch/record/28023/.
- ↑ Emilio Picasso’s contagious enthusiasm for physics, CERN Courier, 27 January 2015, https://cerncourier.com/a/emilio-picassos-contagious-enthusiasm-for-physics/.
- ↑ Archives of Large Electron Positron Collider Division and Committee, LEP and LEPC, https://sis.web.cern.ch/archives/CERN_archive/guide/accelerators/LEP/isalep.
- ↑ Letter April 23rd 1996 – From Christopher Llewellyn Smith to Steve Myers Ref: DG/cce/1811, CERN-ARCH-DG-CLS-05-01-11, https://cds.cern.ch/record/1009675.
- ↑ 7.0 7.1 Stephen Myers - More collaboration for accelerators, CERN Bulletin, No. 05-06/2009, 26 January 2009, https://cds.cern.ch/journal/CERNBulletin/2009/06/News%20Articles/1156859.
- ↑ A Personal History of CERN Particle Colliders (1972–2022), Stephen Myers, Highlights in High-Energy Physics, 2025, 1(1): 9. doi: 10.53941/hihep.2025.100009.
- ↑ IPAC2010 Accelerator Prize article: Particle accelerators and colliders, Stephen Myers, Phys. Rev. Accel. Beams 23 (2020) 124802, 10.1103/PhysRevAccelBeams.23.124802.
For more information, see Wikipedia.