 Test beamline delivered from the SPS. In photo 20 GeV positrons are used to calibrate theAlpha Magnetic Spectrometer. | |
| General properties | |
|---|---|
| Accelerator type | Synchrotron |
| Beam type | protons, heavy ions |
| Target type | Injector forLHC, fixed target |
| Beam properties | |
| Maximum energy | 450 GeV |
| Physical properties | |
| Circumference | 6.9 kilometres (4.3 mi) |
| Coordinates | 46°14′06″N6°02′33″E / 46.23500°N 6.04250°E /46.23500; 6.04250 |
| Institution | CERN |
| Dates of operation | 1976–present |
| Preceded by | SppS |
 | |
| Current particle and nuclear facilities | |
|---|---|
| LHC | Acceleratesprotons and heavyions |
| LEIR | Acceleratesions |
| SPS | Accelerates protons and ions |
| PSB | Accelerates protons |
| PS | Accelerates protons or ions |
| Linac 3 | Injects heavy ions intoLEIR |
| Linac4 | Acceleratesions |
| AD | Deceleratesantiprotons |
| ELENA | Decelerates antiprotons |
| ISOLDE | Produces radioactive ion beams |
| MEDICIS | Produces isotopes for medical purposes |
TheSuper Proton Synchrotron (SPS) is aparticle accelerator of thesynchrotron type atCERN. It is housed in a circular tunnel, 6.9 km (4+1⁄3 miles) in circumference,[1] straddling the border of France and Switzerland nearGeneva, Switzerland.[2]
The SPS was designed by a team led byJohn Adams,director-general of what was then known asLaboratory II. Originally specified as a300 GeV accelerator, the SPS was actually built to be capable of400 GeV, an operating energy it achieved on the official commissioning date of 17 June 1976. However, by that time, this energy had been exceeded byFermilab, which reached an energy of500 GeV on 14 May of that year.[3]
The SPS has been used to accelerateprotons andantiprotons,electrons andpositrons (for use as the injector for theLarge Electron–Positron Collider (LEP)[4]), andheavy ions.
From 1981 to 1991, the SPS operated as a hadron (more precisely, proton–antiproton) collider (as such it was calledSppS), when its beams provided the data for theUA1 andUA2 experiments, which resulted in the discovery of theW and Z bosons. These discoveries and a new technique forcooling particles led to a Nobel Prize forCarlo Rubbia andSimon van der Meer in 1984.
From 2006 to 2012, the SPS was used by theCNGS experiment to produce aneutrinobeam to be detected at theGran Sasso laboratory in Italy, 730 km (450 miles) from CERN.
The SPS is used as the final injector for high-intensity proton beams for theLarge Hadron Collider (LHC), which began preliminary operation on 10 September 2008, for which it accelerates protons from26 to 450 GeV. The LHC itself then accelerates them to severalteraelectronvolts (TeV).
Operation as an injector allows continuation of the ongoingfixed-target research program, where the SPS provides400 GeV proton beams for a number of active fixed-target experiments, includingCOMPASS,NA61/SHINE andNA62.
The SPS has served, and continues to be used as a test bench for new concepts in accelerator physics. In 1999 it served as an observatory for theelectron cloud phenomenon.[5] In 2002 and 2004, SPS producedgold nuclei fromlead targets.[6][7][8] In 2003, SPS was the first machine where theHamiltonian resonance driving terms were directly measured.[9] And in 2004, experiments to cancel the detrimental effects of beam encounters (like those in the LHC) were carried out.[10]
The SPSRF cavities operate at a center frequency of200.2 MHz.
Major scientific discoveries made by experiments that operated at the SPS include the following.
TheLarge Hadron Collider will requirean upgrade to considerably increase itsluminosity during the 2020s. This would require upgrades to the entire linac/pre-injector/injector chain, including the SPS.
As part of this, the SPS will need to be able to handle a much higher intensity beam. One improvement considered in the past was increasing the extraction energy to1 TeV.[13] However, the extraction energy will be kept at450 GeV while other systems are upgraded. Theacceleration system will be modified to handle the higher voltages needed to accelerate a higher intensity beam. The beam dumping system will also be upgraded so it can accept a higher intensity beam without sustaining significant damage.[14]
Media related toSuper Proton Synchrotron at Wikimedia Commons| Large Hadron Collider (LHC) | |
|---|---|
| Large Electron–Positron Collider (LEP) | |
| Super Proton Synchrotron (SPS) | |
| Proton Synchrotron (PS) | |
| Linear accelerators | |
| Other accelerators | |
| ISOLDE facility | |
| Non-accelerator experiments | |
| Future projects | |
| Related articles | |
