LEP superconducting accelerating cavity module
With its 27-kilometre circumference, the Large Electron-Positron (LEP) collider was the largest electron-positron accelerator ever built. The excavation of the LEP tunnel was Europe’s largest civil-engineering project prior to the Channel Tunnel. Three tunnel-boring machines started excavating the tunnel in February 1985 and the ring was completed three years later. In its first phase of operation, LEP consisted of 5176 magnets and 128 accelerating cavities. CERN’s accelerator complex provided the particles and four enormous detectors, ALEPH, DELPHI, L3 and OPAL, observed the collisions. LEP was commissioned in July 1989 and the first beam circulated in the collider on 14 July. The collider's initial energy was chosen to be around 91 GeV, so that Z bosons could be produced. The Z boson and its charged partner the W boson, both discovered at CERN in 1983, are responsible for the weak force, which drives the Sun, for example. Observing the creation and decay of the short-lived Z boson was a critical test of the Standard Model. In the seven years that LEP operated at around 100 GeV it produced around 17 million Z particles. In 1995 LEP was upgraded for a second operation phase, with as many as 288 superconducting accelerating cavities added to double the energy so that the collisions could produce pairs of W bosons. The collider's energy eventually topped 209 GeV in 2000. This object is one of the superconducting cavities from this epoch.
AC;
LEP;
Museum Heritage Collection ;
1995
http://cds.cern.ch/record/2284723/files/AC037.jpg;
http://cds.cern.ch/record/2284723/files/Memorandum .pdf;
http://cds.cern.ch/record/2284723/files/AC037.jpg?subformat=icon-180;
http://cds.cern.ch/record/2284723/files/AC037.gif?subformat=icon;
http://cds.cern.ch/record/2284723/files/Memorandum .gif?subformat=icon;
http://cds.cern.ch/record/2284723/files/Memorandum .jpg?subformat=icon-180;
http://cds.cern.ch/record/2284723/files/Memorandum .pdf?subformat=pdfa;
http://cds.cern.ch/record/2284723/files/Annex .pdf;
http://cds.cern.ch/record/2284723/files/Annex .gif?subformat=icon;
http://cds.cern.ch/record/2284723/files/Annex .jpg?subformat=icon-180;
http://cds.cern.ch/record/2284723/files/Annex .pdf?subformat=pdfa;
Imported from Invenio.
LEP beampipe section
Short section of beampipe from the Large Electron Positron collider (LEP, for short). With its 27-kilometre circumference, LEP was the largest electron-positron accelerator ever built and ran from 1989 to 2000 at CERN. During 11 years of research, LEP's experiments provided a detailed study of the electroweak interaction. Measurements performed at LEP also proved that there are three – and only three – generations of particles of matter. LEP was closed down on 2 November 2000 to make way for the construction of the Large Hadron Collider in the same tunnel.
AC;
LEP;
Museum Heritage Collection ;
1989
http://cds.cern.ch/record/2284288/files/AC14.JPG;
http://cds.cern.ch/record/2284288/files/AC14.jpg?subformat=icon-180;
http://cds.cern.ch/record/2284288/files/AC14.gif?subformat=icon;
Imported from Invenio.
Rock samples from LEP/LHC tunnel excavation
Video: The challenges of LHC civil engineering
Rock samples taken from 0 to 170 m below ground on the CERN site when the LEP (Large Electron Positron collider) pit number 6 was drilled in Bois-chatton (Versonnex). The challenges of LHC civil engineering: A mosaic of works, structures and workers of differents crafts and origins. Three consulting consortia for the engineering and the follow-up of the works. Four industrial consortia for doing the job. A young team of 25 CERN staff, 30 surface buildings, 32 caverns of all sizes, 170 000 m3 of concrete, 420 000 m3 excavated. 1998-2004 : six years of work and 340 millions Swiss Francs.
AC;
LHC ;
1985
http://cds.cern.ch/record/2289741/files/AC063.gif;
http://cds.cern.ch/record/2289741/files/AC063.gif?subformat=icon;
http://cds.cern.ch/record/2289741/files/AC063.gif?subformat=icon-180;
Imported from Invenio.
Slice of a LEP bending magnet
Access to the pictures
This is a slice of a Large Electron Positron collider (LEP, for short) dipole bending magnet, made as a concrete and iron sandwich The bending field needed in LEP is small (about 1000 Gauss), equivalent to two of the magnets people stick on fridge doors. Because it is very difficult to keep a low field steady, a high field was used in iron plates embedded in concrete. A CERN breakthrough in magnet design, LEP dipoles can be tuned easily and are cheaper than conventional magnets. With its 27-kilometre circumference, LEP was the largest electron-positron accelerator ever built and ran from 1989 to 2000 at CERN.
AC;
LEP;
Museum Heritage Collection ;
1989
http://documents.cern.ch/photo/photo-objects/icon-obj-ac-011.gif;
http://documents.cern.ch/cgi-bin/setlink?base=PHO&categ=photo-objects&id=obj-ac-011;
http://www.cern.ch/Public/ACCELERATORS/LepAcc.html;
http://www.cern.ch/public/SCIENCE/lepcolexp.html;
http://outreach.cern.ch/Public/cern/PicturePacks/z_story/captions.html#photo6;
http://www.cern.ch/Public/ACCELERATORS/LepAcc_fr.html;
http://www.cern.ch/public/SCIENCE/lepcolexp_fr.html;
http://cds.cern.ch/record/43879/files/obj-ac-011.jpeg;
http://cds.cern.ch/record/43879/files/obj-ac-011.gif?subformat=icon;
Imported from Invenio.
LEP tunnel monorail
Access to the pictures
A monorail from CERN's Large Electron Positron collider (LEP, for short). It ran around the 27km tunnel, transporting equipment and personnel. With its 27-kilometre circumference, LEP was the largest electron-positron accelerator ever built and ran from 1989 to 2000. During 11 years of research, LEP's experiments provided a detailed study of the electroweak interaction. Measurements performed at LEP also proved that there are three – and only three – generations of particles of matter. LEP was closed down on 2 November 2000 to make way for the construction of the Large Hadron Collider in the same tunnel.
AC;
LEP ;
Museum Heritage Collection ;
1985
http://documents.cern.ch/photo/photo-objects/icon-obj-ac-009.gif;
http://documents.cern.ch/cgi-bin/setlink?base=PHO&categ=photo-objects&id=obj-ac-009;
http://www.cern.ch/Public/ACCELERATORS/LepAcc.html;
http://www.cern.ch/public/SCIENCE/lepcolexp.html;
http://outreach.cern.ch/Public/cern/PicturePacks/z_story/captions.html#photo6;
http://www.cern.ch/Public/ACCELERATORS/LepAcc_fr.html;
http://www.cern.ch/public/SCIENCE/lepcolexp_fr.html;
http://cds.cern.ch/record/43833/files/obj-ac-009.jpeg;
http://cds.cern.ch/record/43833/files/obj-ac-009.gif?subformat=icon;
Imported from Invenio.
Prototype for the ALEPH Time Projection Chamber
This is a prototype endplate piece constructed during R&D for the ALEPH Time Projection Chamber (TPC). ALEPH was one of 4 experiments at CERN's 27km Large Electron Positron collider (LEP) that ran from 1989 to 2000. ALEPH's TPC was a large-volume tracking chamber, 4.4 metres long and 3.6 metres in diameter - the largest TPC in existance at the time. This object is one of the endplates of a “Kind” sector, the smallest of the three types of sectors. The patterns etched into the copper form the cathode pads that measured particle track coordinates in the r-phi direction. It included a laser calibration system, a gating system to prevent space charge buildup, and a new radial pad geometry to improve resolution. the ALEPH TPC allowed for precise momentum measurements of the high-momentum particles from W and Z decays. The following institutes participated: CERN, Athens, Glasgow, Mainz, MPI Munich, INFN-Pisa, INFN-Trieste, Wisconsin.
DE;
LEP;
Detector;
ALEPH;
Time Projection Chamber;
Museum Heritage Collection ;
1980
http://cds.cern.ch/record/2266346/files/DE085.JPG;
http://cds.cern.ch/record/2266346/files/DE085.gif?subformat=icon;
http://cds.cern.ch/record/2266346/files/DE085.jpg?subformat=icon-180;
http://cds.cern.ch/record/2266346/files/DE085b.jpg;
http://cds.cern.ch/record/2266346/files/DE085b.jpg?subformat=icon-180;
http://cds.cern.ch/record/2266346/files/DE085b.gif?subformat=icon;
Imported from Invenio.
Array of lead-glass blocks from OPAL
OPAL experiment
OPAL was one of the 4 experiments at CERN's Large Electron Positron collider (LEP) which ran from 1989 - 2000. This array of 96 lead glass bricks formed part of the OPAL electromagnetic calorimeter. In total, there were 9440 lead glass counters in the OPAL electromagnetic calorimeter, made of Schott type SF57 glass and each block weighs about 25 kg and consists of 76% PbO by weight. Each block has a Hamamatsu R2238 photomultiplier glued on to it. The complete detector was in the form of a cylinder 7m long and 6m in diameter. It was used to measure the energy of electrons and photons produced in LEP electron positron collisions.
eng
DE;
LEP;
lead glass;
Calorimeter;
Detector;
electromagnetic;
Museum Heritage Collection ;
http://documents.cern.ch/photo/photo-objects/icon-obj-de-057.gif;
http://opal.web.cern.ch/Opal/;
http://preprints.cern.ch/cgi-bin/setlink?base=PHO&categ=photo-objects&id=obj-de-057;
http://cds.cern.ch/record/43978/files/obj-de-057.jpeg;
http://cds.cern.ch/record/43978/files/obj-de-057.gif?subformat=icon;
Imported from Invenio.