The Cornell Electron Storage Ring (CESR, pronounced Caesar) is a particle accelerator operated by Cornell University and located 40 feet beneath a football field on their Ithaca campus. [1] The accelerator has contributed to fundamental research in high energy physics and accelerator physics, as well as solid state physics, biology, art history and other fields through its use as a synchrotron light source. For many years, CESR held the world luminosity record for electron-positron collisions. [2]
CESR pioneered several new accelerator techniques, including superconducting radio-frequency cavities and pretzel orbits.
CESR was built in the already existing tunnel for the 10 GeV synchrotron and was originally constructed as an electron-positron collider. The project was led by Cornell physicist Maury Tigner who devised a "fiendishly clever" method of filling the ring with positrons generated by the synchrotron. [2] It delivered its first collisions in April 1979 setting the world record for the highest luminosity electron-positron collisions. From this point on, the accelerator provided a reliable beam of high energy electrons and positrons to the CLEO and CUSB particle detectors. The name CLEO is a play on words and not an acronym. The name was chosen because it is short for Cleopatra due to her relationship with Caesar.
Collisions occurred at a center of mass energy ranging from 3.5 GeV to 12 GeV at its peak. This turned out to be ideal for the study of the B meson and data from these collisions provided physicists with many new insights into the physics of fundamental particles. The CLEO detector alone resulted in over 200 publications in Physical Review Letters [3] . CESR installed sets of wiggler magnets in the early 2000s to allow operation at lower energies for the CLEO-c project. The accelerator continued to provide useful data until the early 2000s when it was superseded by more powerful machines.
CESR now powers the state of the art synchrotron light source called CHESS. This NSF user facility is one of only five in the world that can generate the high energy x-rays needed for research in fields such as solid state physics, biology, material science, art history, among others. Over 1000 scientists from all over the world visit CHESS to perform their research every year. Data gathered at CHESS has contributed to the multiple Nobel Prizes including the 2003 and 2009 Nobel Prize in Chemistry. [4] In 2017, CHESS received a $15 million award (called CHESS-U) from the state of New York to help upgrade their facility. CHESS-U will increase the brightness of the x-ray source by a factor of 1,000 allowing CHESS to maintain world leadership as an x-ray user facility. [5] In addition, several more x-ray hutches will be added to the facility which will enable more scientists to share the powerful x-ray beam at the same time.
The Deutsches Elektronen-Synchrotron, commonly referred to by the abbreviation DESY, is a national research center in Germany. It operates particle accelerators used to investigate the structure of matter, and conducts a broad spectrum of inter-disciplinary scientific research in three main areas: particle and high energy physics; photon science, and the development, construction and operation of particle accelerators. Its name refers to its first project, an electron synchrotron. DESY is publicly financed by the Federal Republic of Germany, the States of Germany, and the German Research Foundation (DFG). DESY is a member of the Helmholtz Association and operates at sites in Hamburg and Zeuthen.
SLAC National Accelerator Laboratory, originally named the Stanford Linear Accelerator Center, is a United States Department of Energy National Laboratory operated by Stanford University under the programmatic direction of the U.S. Department of Energy Office of Science and located in Menlo Park, California. It is the site of the Stanford Linear Accelerator, a 3.2 kilometer (2-mile) linear accelerator constructed in 1966 and shut down in the 2000s, that could accelerate electrons to energies of 50 GeV.
ISABELLE was a 200+200 GeV proton–proton colliding beam particle accelerator partially built by the United States government at Brookhaven National Laboratory in Upton, New York, before it was cancelled in July, 1983.
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.
A synchrotron is a particular type of cyclic particle accelerator, descended from the cyclotron, in which the accelerating particle beam travels around a fixed closed-loop path. The magnetic field which bends the particle beam into its closed path increases with time during the accelerating process, being synchronized to the increasing kinetic energy of the particles. The synchrotron is one of the first accelerator concepts to enable the construction of large-scale facilities, since bending, beam focusing and acceleration can be separated into different components. The most powerful modern particle accelerators use versions of the synchrotron design. The largest synchrotron-type accelerator, also the largest particle accelerator in the world, is the 27-kilometre-circumference (17 mi) Large Hadron Collider (LHC) near Geneva, Switzerland, built in 2008 by the European Organization for Nuclear Research (CERN). It can accelerate beams of protons to an energy of 6.5 tera electronvolts (TeV or 1012 eV).
The Compact Linear Collider (CLIC) is a concept for a future linear particle accelerator that aims to explore the next energy frontier. CLIC would collide electrons with positrons and is currently the only mature option for a multi-TeV linear collider. The accelerator would be between 11 and 50 km long, more than ten times longer than the existing Stanford Linear Accelerator (SLAC) in California, USA. CLIC is proposed to be built at CERN, across the border between France and Switzerland near Geneva, with first beams starting by the time the Large Hadron Collider (LHC) has finished operations around 2035.
The Underground Area 2 (UA2) experiment was a high-energy physics experiment at the Proton-Antiproton Collider — a modification of the Super Proton Synchrotron (SPS) — at CERN. The experiment ran from 1981 until 1990, and its main objective was to discover the W and Z bosons. UA2, together with the UA1 experiment, succeeded in discovering these particles in 1983, leading to the 1984 Nobel Prize in Physics being awarded to Carlo Rubbia and Simon van der Meer. The UA2 experiment also observed the first evidence for jet production in hadron collisions in 1981, and was involved in the searches of the top quark and of supersymmetric particles. Pierre Darriulat was the spokesperson of UA2 from 1981 to 1986, followed by Luigi Di Lella from 1986 to 1990.
The International Linear Collider (ILC) is a proposed linear particle accelerator. It is planned to have a collision energy of 500 GeV initially, with the possibility for a later upgrade to 1000 GeV (1 TeV). Although early proposed locations for the ILC were Japan, Europe (CERN) and the USA (Fermilab), the Kitakami highland in the Iwate prefecture of northern Japan has been the focus of ILC design efforts since 2013. The Japanese government is willing to contribute half of the costs, according to the coordinator of study for detectors at the ILC.
The High Energy Accelerator Research Organization, known as KEK, is a Japanese organization whose purpose is to operate the largest particle physics laboratory in Japan, situated in Tsukuba, Ibaraki prefecture. It was established in 1997. The term "KEK" is also used to refer to the laboratory itself, which employs approximately 695 employees. KEK's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics, material science, structural biology, radiation science, computing science, nuclear transmutation and so on. Numerous experiments have been constructed at KEK by the internal and international collaborations that have made use of them. Makoto Kobayashi, emeritus professor at KEK, is known globally for his work on CP-violation, and was awarded the 2008 Nobel Prize in Physics.
The Budker Institute of Nuclear Physics (BINP) is one of the major centres of advanced study of nuclear physics in Russia. It is located in the Siberian town Akademgorodok, on Academician Lavrentiev Avenue. The institute was founded by Gersh Budker in 1959. Following his death in 1977, the institute was renamed in honour of Academician Budker.
The Positron-Electron Tandem Ring Accelerator (PETRA) is one of the particle accelerators at the German national laboratory DESY in Hamburg, Germany. At the time of its construction, it was the biggest storage ring of its kind and still is DESY's second largest synchrotron after HERA. PETRA’s original purpose was research in elementary particle physics. From 1978 to 1986 it was used to study electron–positron collisions with the four experiments JADE, MARK-J, PLUTO and TASSO. The discovery of the gluon, the carrier particle of the strong nuclear force, by the TASSO collaboration in 1979 is counted as one of the biggest successes. PETRA was able to accelerate electrons and positrons to 19 GeV. Research at PETRA led to an intensified international use of the facilities at DESY. Scientists from China, France, Israel, the Netherlands, Norway, the United Kingdom and the USA participated in the first experiments at PETRA alongside many German colleagues.
The Cornell Laboratory for Accelerator-based Sciences and Education (CLASSE) is a particle accelerator facility located in Wilson Laboratory on the Cornell University campus in Ithaca, NY. CLASSE formed from the merger of the Cornell High-Energy Synchrotron Source (CHESS) and the Laboratory for Elementary-Particle Physics (LEPP) in July 2006. Ritchie Patterson is the Director of CLASSE.
The ISR was a particle accelerator at CERN. It was the world's first hadron collider, and ran from 1971 to 1984, with a maximum center of mass energy of 62 GeV. From its initial startup, the collider itself had the capability to produce particles like the J/ψ and the upsilon, as well as observable jet structure; however, the particle detector experiments were not configured to observe events with large momentum transverse to the beamline, leaving these discoveries to be made at other experiments in the mid-1970s. Nevertheless, the construction of the ISR involved many advances in accelerator physics, including the first use of stochastic cooling, and it held the record for luminosity at a hadron collider until surpassed by the Tevatron in 2004.
Boyce Dawkins McDaniel was an American nuclear physicist who worked on the Manhattan Project and later directed the Cornell University Laboratory of Nuclear Studies (LNS). McDaniel was skilled in constructing "atom smashing" devices to study the fundamental structure of matter and helped to build the most powerful particle accelerators of his time. Together with his graduate student, he invented the pair spectrometer.
A particle accelerator is a machine that uses electromagnetic fields to propel charged particles to very high speeds and energies, and to contain them in well-defined beams.
The Beijing Electron–Positron Collider II is a Chinese electron–positron collider, a type of particle accelerator, located in Beijing, People's Republic of China. It has been in operation since 2008 and has a circumference of 240.4 m.
A Muon Collider is a proposed particle accelerator facility in its conceptual design stage that collides muon beams for precision studies of the Standard Model and for direct searches of new physics. Muons belong to the second generation of leptons, they are typically produced in high-energy collisions either naturally or artificially. The main challenge of such a collider is the short lifetime of muons.
The INFN National Laboratory of Frascati (LNF) was founded in 1954 with the objective of furthering particle physics research, and more specifically to host the 1.1 GeV electrosynchrotron, the first accelerator ever built in Italy. The Laboratory later developed the first ever electron-positron collider: from the first prototype AdA, which demonstrated the feasibility, to the ring ADONE and later on to DAΦNE, still operative today (2022). LNF was also the proposed site of the cancelled particle accelerator SuperB.
The Future Circular Collider (FCC) is a proposed particle accelerator with an energy significantly above that of previous circular colliders, such as the Super Proton Synchrotron, the Tevatron, and the Large Hadron Collider (LHC). The FCC project is considering three scenarios for collision types: FCC-hh, for hadron-hadron collisions, including proton-proton and heavy ion collisions. FCC-ee, for electron-positron collisions, and FCC-eh, for electron-hadron collisions.
The Super Proton–Antiproton Synchrotron was a particle accelerator that operated at CERN from 1981 to 1991. To operate as a proton-antiproton collider the Super Proton Synchrotron (SPS) underwent substantial modifications, altering it from a one beam synchrotron to a two-beam collider. The main experiments at the accelerator were UA1 and UA2, where the W and Z boson were discovered in 1983. Carlo Rubbia and Simon van der Meer received the 1984 Nobel Prize in Physics for their decisive contribution to the SppS-project, which led to the discovery of the W and Z bosons. Other experiments conducted at the SppS were UA4, UA5 and UA8.