
The Cornell Electron Storage Ring (CESR, pronounced
Caesar
Gaius Julius Caesar (; ; 12 July 100 BC – 15 March 44 BC), was a Roman general and statesman. A member of the First Triumvirate, Caesar led the Roman armies in the Gallic Wars before defeating his political rival Pompey in a civil war, an ...
) is a particle accelerator operated by
Cornell University
Cornell University is a private statutory land-grant research university based in Ithaca, New York. It is a member of the Ivy League. Founded in 1865 by Ezra Cornell and Andrew Dickson White, Cornell was founded with the intention to ...
and located 40 feet beneath a football field on their
Ithaca
Ithaca most commonly refers to:
* Homer's Ithaca, an island featured in Homer's ''Odyssey''
* Ithaca (island), an island in Greece, possibly Homer's Ithaca
*Ithaca, New York, a city, and home of Cornell University and Ithaca College
Ithaca, Ithak ...
campus. 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
A synchrotron light source is a source of electromagnetic radiation (EM) usually produced by a storage ring, for scientific and technical purposes. First observed in synchrotrons, synchrotron light is now produced by storage rings and other s ...
. For many years, CESR held the world luminosity record for electron-positron collisions.
CESR pioneered several new accelerator techniques, including
superconducting
Superconductivity is a set of physical properties observed in certain materials where electrical resistance vanishes and magnetic flux fields are expelled from the material. Any material exhibiting these properties is a superconductor. Unlike ...
radio-frequency cavities and pretzel orbits.
Electron Positron Collider
CESR was built in the already existing tunnel for the 10 GeV
synchrotron
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 p ...
and was originally constructed as an
electron
The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family,
and are generally thought to be elementary partic ...
-
positron
The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. It has an electric charge of +1 '' e'', a spin of 1/2 (the same as the electron), and the same mass as an electron. When a positron collide ...
collider
A collider is a type of particle accelerator which brings two opposing particle beams together such that the particles collide. Colliders may either be ring accelerators or linear accelerators.
Colliders are used as a research tool in particle ...
. The project was led by Cornell physicist
Maury Tigner Maury Tigner (born 22 April 1937) is an American physicist working on particle accelerators and experimental particle physics.
Tigner studied physics at the Rensselaer Polytechnic Institute until 1958 and received a PhD degree from Cornell Unive ...
who devised a "fiendishly clever" method of filling the ring with positrons generated by the synchrotron.
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 Cleo may refer to:
Entertainment
* ''Cleo'' (magazine), an Australian magazine established in 1972, now active in Indonesia, Malaysia, Singapore, and Thailand
* Cleo (group), a South Korean girl group formed in 1999
* ''Cleo'' (play), by Lawren ...
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
Cleopatra VII Philopator ( grc-gre, Κλεοπάτρα Φιλοπάτωρ}, "Cleopatra the father-beloved"; 69 BC10 August 30 BC) was Queen of the Ptolemaic Kingdom of Ancient Egypt, Egypt from 51 to 30 BC, and its last active ruler. ...
due to her relationship with
Caesar
Gaius Julius Caesar (; ; 12 July 100 BC – 15 March 44 BC), was a Roman general and statesman. A member of the First Triumvirate, Caesar led the Roman armies in the Gallic Wars before defeating his political rival Pompey in a civil war, an ...
.
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
In particle physics, B mesons are mesons composed of a bottom antiquark and either an up (), down (), strange () or charm quark (). The combination of a bottom antiquark and a top quark is not thought to be possible because of the top quark's s ...
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
''Physical Review Letters'' (''PRL''), established in 1958, is a peer-reviewed, scientific journal that is published 52 times per year by the American Physical Society. As also confirmed by various measurement standards, which include the '' Jou ...
'.'' 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.
Cornell High Energy Synchrotron Source (CHESS)
CESR now powers the state of the art
synchrotron light source
A synchrotron light source is a source of electromagnetic radiation (EM) usually produced by a storage ring, for scientific and technical purposes. First observed in synchrotrons, synchrotron light is now produced by storage rings and other s ...
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
)
, image = Nobel Prize.png
, alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...
. 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.
[{{Cite news, url=https://ithacavoice.com/2017/11/cornell-awarded-15-million-upgrade-high-tech-research-facility-boosting-regional-business/, title=Cornell awarded $15 million to upgrade high-tech research facility, boosting regional business, work=The Ithaca Voice, access-date=2018-06-17, language=en-US] 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.
See also
*
List of accelerators in particle physics
A list of particle accelerators used for particle physics experiments. Some early particle accelerators that more properly did nuclear physics, but existed prior to the separation of particle physics from that field, are also included. Although a m ...
References
External links
Cornell Laboratory for Accelerator-based ScienceS and Education (CLASSE), CESRCHESS Homepage
Particle physics facilities
Cornell University
Particle accelerators