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113-406: The Superconducting Super Collider ( SSC ) (also nicknamed the "Desertron" ) was a particle accelerator complex under construction in the vicinity of Waxahachie , Texas , United States. Its planned ring circumference was 87.1 kilometers (54.1 mi) with an energy of 20 TeV per proton and was designed to be the world's largest and most energetic particle accelerator. The laboratory director

226-411: A klystron and a complex bending magnet arrangement which produces a beam of energy 6–30  MeV . The electrons can be used directly or they can be collided with a target to produce a beam of X-rays . The reliability, flexibility and accuracy of the radiation beam produced has largely supplanted the older use of cobalt-60 therapy as a treatment tool. In the circular accelerator, particles move in

339-737: A statement for the record for various subcommittees of the United States Congress. Most GAO studies and reports are initiated by requests from members of Congress, including requests mandated in statute, and so reflect concerns of current political import, for example to study the impact of a government-wide hiring freeze. Many reports are issued periodically and take a long view of U.S. agencies' operations. The GAO also produces annual reports on key issues such as Duplication and Cost savings and High-Risk Update. The GAO prepares some 900 reports annually. The GAO publishes reports and information relating to, inter alia : Each year

452-405: A 3 km long waveguide, buried in a tunnel and powered by hundreds of large klystrons . It is still the largest linear accelerator in existence, and has been upgraded with the addition of storage rings and an electron-positron collider facility. It is also an X-ray and UV synchrotron photon source. General Accounting Office The United States Government Accountability Office ( GAO )

565-402: A circle until they reach enough energy. The particle track is typically bent into a circle using electromagnets . The advantage of circular accelerators over linear accelerators ( linacs ) is that the ring topology allows continuous acceleration, as the particle can transit indefinitely. Another advantage is that a circular accelerator is smaller than a linear accelerator of comparable power (i.e.

678-553: A constant frequency by a RF accelerating power source, as the beam spirals outwards continuously. The particles are injected in the center of the magnet and are extracted at the outer edge at their maximum energy. Cyclotrons reach an energy limit because of relativistic effects whereby the particles effectively become more massive, so that their cyclotron frequency drops out of sync with the accelerating RF. Therefore, simple cyclotrons can accelerate protons only to an energy of around 15 million electron volts (15 MeV, corresponding to

791-629: A fictional version of the Superconducting Super Collider. On the February 25, 2001, episode of Futurama , entitled “ That’s Lobstertainment! ,” a robot comedian makes a Super Collider pun and, in tongue-in-cheek fashion, states that a Super Collider was built. On the March 6, 2002, episode of The West Wing , the supercollider is discussed when Sam Seaborn is helping an old college physics professor get funding to complete

904-581: A forefront United States High Energy Physics Program in the next five to ten years.” the HEPAP subpanel recommended that the US build the Superconducting Super Collider. Fermilab director and subsequent Nobel physics prizewinner Leon Lederman was a very prominent early supporter – some sources say the architect or proposer – of the Superconducting Super Collider project, as well as a major proponent and advocate throughout its lifetime. A Central Design Group (CDG)

1017-696: A hole in the plate, the polarity is switched so that the plate now repels them and they are now accelerated by it towards the next plate. Normally a stream of "bunches" of particles are accelerated, so a carefully controlled AC voltage is applied to each plate to continuously repeat this process for each bunch. As the particles approach the speed of light the switching rate of the electric fields becomes so high that they operate at radio frequencies , and so microwave cavities are used in higher energy machines instead of simple plates. Linear accelerators are also widely used in medicine , for radiotherapy and radiosurgery . Medical grade linacs accelerate electrons using

1130-451: A huge tunnel, that was somewhat of a distortion. The tunneling and conventional facility buildout budget was only about ten percent of the total budgeted cost (1.1 billion dollars out of a total cost of 10 billion). The major cost item was the magnets, still in laboratory development phase, consequently with a higher level of uncertainty attached to the final cost. The ring circumference of the LHC

1243-677: A leading promoter and advocate of the SSC, wrote a popular science book in the context of the project's last years and loss of congressional support. Published in 1993, The God Particle: If the Universe Is the Answer, What Is the Question? sought to promote awareness of the significance of the scientific work which the SSC would have supported. The book popularized the nickname "the God particle" for

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1356-427: A linac would have to be extremely long to have the equivalent power of a circular accelerator). Depending on the energy and the particle being accelerated, circular accelerators suffer a disadvantage in that the particles emit synchrotron radiation . When any charged particle is accelerated, it emits electromagnetic radiation and secondary emissions . As a particle traveling in a circle is always accelerating towards

1469-574: A list that encompasses the public, private, and non-profit sectors. The GAO is headed by the comptroller general of the U.S. , a professional and non-partisan position in the U.S. government. The comptroller general is appointed by the president , by and with the advice and consent of the Senate , for a fifteen-year, non-renewable term. The president selects a nominee from a list of at least three individuals recommended by an eight-member bipartisan, bicameral commission of congressional leaders. During such

1582-514: A magnetic field which is fixed in time, but with a radial variation to achieve strong focusing , allows the beam to be accelerated with a high repetition rate but in a much smaller radial spread than in the cyclotron case. Isochronous FFAs, like isochronous cyclotrons, achieve continuous beam operation, but without the need for a huge dipole bending magnet covering the entire radius of the orbits. Some new developments in FFAs are covered in. A Rhodotron

1695-565: A new job there. A subsequent episode on the April 1, 2021, episode shows an exterior shot of the facility with Dr. Sturgis receiving a phone call from Sheldon's grandmother ( Annie Potts ). In 2021, the project was cited as a case study of the hypothetical demon of Bureaucratic Chaos, which "blocks good things from happening" at the United States Department of Energy . Particle accelerator Large accelerators include

1808-519: A particle and an atomic nucleus. Beams of high-energy particles are useful for fundamental and applied research in the sciences and also in many technical and industrial fields unrelated to fundamental research. There are approximately 30,000 accelerators worldwide; of these, only about 1% are research machines with energies above 1 GeV , while about 44% are for radiotherapy , 41% for ion implantation , 9% for industrial processing and research, and 4% for biomedical and other low-energy research. For

1921-649: A public relations campaign to lobby Congress directly in support of the project. In February, the General Accounting Office reported a $ 630 million overrun in the $ 1.25 billion construction budget. By March, the New York Times reported the estimated total cost had grown to $ 8.4 billion. In June, the non-profit Project on Government Oversight released a draft audit report by the Department of Energy 's Inspector General heavily criticizing

2034-432: A reactor to produce tritium . An example of this type of machine is LANSCE at Los Alamos National Laboratory . Electrons propagating through a magnetic field emit very bright and coherent photon beams via synchrotron radiation . It has numerous uses in the study of atomic structure, chemistry, condensed matter physics, biology, and technology. A large number of synchrotron light sources exist worldwide. Examples in

2147-426: A shorter distance in each orbit than they would in a classical cyclotron, thus remaining in phase with the accelerating field. The advantage of the isochronous cyclotron is that it can deliver continuous beams of higher average intensity, which is useful for some applications. The main disadvantages are the size and cost of the large magnet needed, and the difficulty in achieving the high magnetic field values required at

2260-904: A special class of light sources based on synchrotron radiation that provides shorter pulses with higher temporal coherence . A specially designed FEL is the most brilliant source of x-rays in the observable universe. The most prominent examples are the LCLS in the U.S. and European XFEL in Germany. More attention is being drawn towards soft x-ray lasers, which together with pulse shortening opens up new methods for attosecond science . Apart from x-rays, FELs are used to emit terahertz light , e.g. FELIX in Nijmegen, Netherlands, TELBE in Dresden, Germany and NovoFEL in Novosibirsk, Russia. Thus there

2373-474: A speed of roughly 10% of c ), because the protons get out of phase with the driving electric field. If accelerated further, the beam would continue to spiral outward to a larger radius but the particles would no longer gain enough speed to complete the larger circle in step with the accelerating RF. To accommodate relativistic effects the magnetic field needs to be increased to higher radii as is done in isochronous cyclotrons . An example of an isochronous cyclotron

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2486-649: A straight line, or circular , using magnetic fields to bend particles in a roughly circular orbit. Magnetic induction accelerators accelerate particles by induction from an increasing magnetic field, as if the particles were the secondary winding in a transformer. The increasing magnetic field creates a circulating electric field which can be configured to accelerate the particles. Induction accelerators can be either linear or circular. Linear induction accelerators utilize ferrite-loaded, non-resonant induction cavities. Each cavity can be thought of as two large washer-shaped disks connected by an outer cylindrical tube. Between

2599-452: A target or an external beam in beam "spills" typically every few seconds. Since high energy synchrotrons do most of their work on particles that are already traveling at nearly the speed of light c , the time to complete one orbit of the ring is nearly constant, as is the frequency of the RF cavity resonators used to drive the acceleration. In modern synchrotrons, the beam aperture is small and

2712-446: A term, the comptroller general has standing to pursue litigation to compel access to federal agency information. The comptroller general may not be removed by the president, but only by Congress through impeachment or joint resolution for specific reasons. Since 1921, there have been only eight comptrollers general, and no formal attempt has ever been made to remove a comptroller general. Labor-management relations became fractious during

2825-544: Is Gene Dodaro , who has served in the position since March 13, 2008. The work of the GAO is done at the request of congressional committees or subcommittees or is mandated by public laws or committee reports. It also undertakes research under the authority of the comptroller general. It supports congressional oversight by: As a result of its work, GAO produces: The GAO also produces special publications on specific issues of general interest to many Americans, such as its report on

2938-476: Is 27 km (17 mi), compared to the planned 87.1 kilometers (54.1 mi) of the SSC. The LHC's advantage in terms of cost was the use of the pre-existing engineering infrastructure and 27 km long cavern of the Large Electron–Positron Collider , and its use of a different, innovative magnet design to bend the higher energy particles into the available tunnel. The LHC eventually cost

3051-402: Is 3 km (1.9 mi) long. SLAC was originally an electron – positron collider but is now a X-ray Free-electron laser . Linear high-energy accelerators use a linear array of plates (or drift tubes) to which an alternating high-energy field is applied. As the particles approach a plate they are accelerated towards it by an opposite polarity charge applied to the plate. As they pass through

3164-405: Is a circular magnetic induction accelerator, invented by Donald Kerst in 1940 for accelerating electrons . The concept originates ultimately from Norwegian-German scientist Rolf Widerøe . These machines, like synchrotrons, use a donut-shaped ring magnet (see below) with a cyclically increasing B field, but accelerate the particles by induction from the increasing magnetic field, as if they were

3277-413: Is a great demand for electron accelerators of moderate ( GeV ) energy, high intensity and high beam quality to drive light sources. Everyday examples of particle accelerators are cathode ray tubes found in television sets and X-ray generators. These low-energy accelerators use a single pair of electrodes with a DC voltage of a few thousand volts between them. In an X-ray generator, the target itself

3390-558: Is an independent, nonpartisan government agency within the legislative branch that provides auditing , evaluative , and investigative services for the United States Congress . It is the supreme audit institution of the federal government of the United States . It identifies its core "mission values" as: accountability, integrity, and reliability. It is also known as the "congressional watchdog". The agency

3503-509: Is an industrial electron accelerator first proposed in 1987 by J. Pottier of the French Atomic Energy Agency (CEA) , manufactured by Belgian company Ion Beam Applications . It accelerates electrons by recirculating them across the diameter of a cylinder-shaped radiofrequency cavity. A Rhodotron has an electron gun, which emits an electron beam that is attracted to a pillar in the center of the cavity. The pillar has holes

Superconducting Super Collider - Misplaced Pages Continue

3616-422: Is commonly used for sterilization. Electron beams are an on-off technology that provide a much higher dose rate than gamma or X-rays emitted by radioisotopes like cobalt-60 ( Co) or caesium-137 ( Cs). Due to the higher dose rate, less exposure time is required and polymer degradation is reduced. Because electrons carry a charge, electron beams are less penetrating than both gamma and X-rays. Historically,

3729-481: Is composed of 15 mission teams that work on reports in a given subject area. Missions teams are headed by a Managing Director which fall under the Senior Executive Service . The current slate of mission teams is: In addition to its mission teams, the GAO also has 16 operations and staff components that support their work and carryout other agency functions, including its bid decisions. The GAO

3842-404: Is determined by the accelerating voltage , which is limited by electrical breakdown . Electrodynamic or electromagnetic accelerators, on the other hand, use changing electromagnetic fields (either magnetic induction or oscillating radio frequency fields) to accelerate particles. Since in these types the particles can pass through the same accelerating field multiple times, the output energy

3955-526: Is headed by the Comptroller General of the United States . The comptroller general is appointed by the president with the advice and consent of the Senate. When a vacancy occurs in the office of the comptroller general, Congress establishes a commission to recommend individuals to the president. The commission consists of the following: The commission must recommend at least three individuals to

4068-557: Is limited to official use in order to protect national security. The variety of their reports' topics range from Federal Budget and Fiscal Issues to Financial Management, Education, Retirement Issues, Defense, Homeland Security, Administration of Justice, Health Care, Information Management and Technology, Natural Resources, Environment, International Affairs, Trade, Financial Markets, Housing, Government Management and Human Capital, and Science and Technology Assessments and Analytics. The GAO often produces highlights of its reports that serve as

4181-560: Is more often used for accelerators that employ oscillating rather than static electric fields. Due to the high voltage ceiling imposed by electrical discharge, in order to accelerate particles to higher energies, techniques involving dynamic fields rather than static fields are used. Electrodynamic acceleration can arise from either of two mechanisms: non-resonant magnetic induction , or resonant circuits or cavities excited by oscillating radio frequency (RF) fields. Electrodynamic accelerators can be linear , with particles accelerating in

4294-399: Is not limited by the strength of the accelerating field. This class, which was first developed in the 1920s, is the basis for most modern large-scale accelerators. Rolf Widerøe , Gustav Ising , Leó Szilárd , Max Steenbeck , and Ernest Lawrence are considered pioneers of this field, having conceived and built the first operational linear particle accelerator , the betatron , as well as

4407-571: Is one of the electrodes. A low-energy particle accelerator called an ion implanter is used in the manufacture of integrated circuits . At lower energies, beams of accelerated nuclei are also used in medicine as particle therapy , for the treatment of cancer. DC accelerator types capable of accelerating particles to speeds sufficient to cause nuclear reactions are Cockcroft–Walton generators or voltage multipliers , which convert AC to high voltage DC, or Van de Graaff generators that use static electricity carried by belts. Electron beam processing

4520-402: Is still extremely popular today, with the electrostatic accelerators greatly out-numbering any other type, they are more suited to lower energy studies owing to the practical voltage limit of about 1 MV for air insulated machines, or 30 MV when the accelerator is operated in a tank of pressurized gas with high dielectric strength , such as sulfur hexafluoride . In a tandem accelerator

4633-468: Is that the curvature of the particle trajectory is proportional to the particle charge and to the magnetic field, but inversely proportional to the (typically relativistic ) momentum . The earliest operational circular accelerators were cyclotrons , invented in 1929 by Ernest Lawrence at the University of California, Berkeley . Cyclotrons have a single pair of hollow D-shaped plates to accelerate

Superconducting Super Collider - Misplaced Pages Continue

4746-585: Is that the magnetic field need only be present over the actual region of the particle orbits, which is much narrower than that of the ring. (The largest cyclotron built in the US had a 184-inch-diameter (4.7 m) magnet pole, whereas the diameter of synchrotrons such as the LEP and LHC is nearly 10 km. The aperture of the two beams of the LHC is of the order of a centimeter.) The LHC contains 16 RF cavities, 1232 superconducting dipole magnets for beam steering, and 24 quadrupoles for beam focusing. Even at this size,

4859-604: Is the PSI Ring cyclotron in Switzerland, which provides protons at the energy of 590 MeV which corresponds to roughly 80% of the speed of light. The advantage of such a cyclotron is the maximum achievable extracted proton current which is currently 2.2 mA. The energy and current correspond to 1.3 MW beam power which is the highest of any accelerator currently existing. A classic cyclotron can be modified to increase its energy limit. The historically first approach

4972-501: Is the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory . Particle accelerators can also produce proton beams, which can produce proton-rich medical or research isotopes as opposed to the neutron-rich ones made in fission reactors ; however, recent work has shown how to make Mo , usually made in reactors, by accelerating isotopes of hydrogen, although this method still requires

5085-946: The Diamond Light Source which has been built at the Rutherford Appleton Laboratory in England or the Advanced Photon Source at Argonne National Laboratory in Illinois , USA. High-energy X-rays are useful for X-ray spectroscopy of proteins or X-ray absorption fine structure (XAFS), for example. Synchrotron radiation is more powerfully emitted by lighter particles, so these accelerators are invariably electron accelerators. Synchrotron radiation allows for better imaging as researched and developed at SLAC's SPEAR . Fixed-Field Alternating Gradient accelerators (FFA)s , in which

5198-619: The European Parliamentary Technology Assessment (EPTA) as an associate member. In 2019, the GAO established a new mission team, the Science, Technology Assessment, and Analytics team, which has primary responsibility for technology assessments. The GAO has published a TA Design Handbook to help technology assessment teams analyze the impact of technology and make complex issues more easily understood and useful to policymakers. The GAO defines TA as

5311-596: The Higgs boson . The closing of the SSC had adverse consequences for the southern part of the Dallas–Fort Worth Metroplex , contributing to a mild recession especially in those parts of Dallas which lay south of the Trinity River . When the project was canceled, 22.5 km (14.0 mi) of tunnel and 17 shafts to the surface were already dug, and nearly two billion dollars had already been spent on

5424-565: The Relativistic Heavy Ion Collider at Brookhaven National Laboratory in New York and the largest accelerator, the Large Hadron Collider near Geneva, Switzerland, operated by CERN . It is a collider accelerator, which can accelerate two beams of protons to an energy of 6.5  TeV and cause them to collide head-on, creating center-of-mass energies of 13 TeV. There are more than 30,000 accelerators in operation around

5537-435: The cyclotron . Because the target of the particle beams of early accelerators was usually the atoms of a piece of matter, with the goal being to create collisions with their nuclei in order to investigate nuclear structure, accelerators were commonly referred to as atom smashers in the 20th century. The term persists despite the fact that many modern accelerators create collisions between two subatomic particles , rather than

5650-823: The GAO analysts bargaining unit; the local voted to name itself IFPTE Local 1921, in honor of the date of the GAO's establishment. On February 14, 2008, the GAO analysts' union approved its first-ever negotiated pay contract with management; of just over 1,200 votes, 98% were in favor of the contract. The GAO also establishes standards for audits of government organizations, programs, activities, and functions, and of government assistance received by contractors, nonprofit organizations, and other nongovernmental organizations. These standards, often referred to as Generally Accepted Government Auditing Standards (GAGAS), are to be followed by auditors and audit organizations when required by law, regulation, agreement, contract, or policy. These standards pertain to auditors' professional qualifications,

5763-590: The GAO issues an audit report on the financial statements of the United States Government. The 2010 Financial Report of the United States Government was released on December 21, 2010. The accompanying press release states that the GAO 'cannot render an opinion on the 2010 consolidated financial statements of the federal government , because of widespread material internal control weaknesses, significant uncertainties, and other limitations'. As part of its initiative to advocate sustainability ,

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5876-536: The GAO publishes a Federal Fiscal Outlook Report, as well as data relating to the deficit . The U.S. deficit is presented on a cash rather than accruals basis, although the GAO notes that the accrual deficit "provides more information on the longer-term implications of the government's annual operations". In FY 2010, the US federal government had a net operating cost of $ 2,080 billion, although since this includes accounting provisions (estimates of future liabilities),

5989-687: The GAO's current mission statement, the agency exists to support the Congress in meeting its constitutional responsibilities and to help improve the performance and ensure the accountability of the federal government for the benefit of the American people. The name was changed in 2004 to the Government Accountability Office by the GAO Human Capital Reform Act to better reflect the mission of

6102-665: The IRS, the Centers for Medicare and Medicaid Services, the Department of Veterans Affairs, and the Department of Homeland Security, among others. Unsuccessful bidders for government contracts may submit protests if they have reason to challenge an agency's decision, and the GAO may then release a report on the decision, redacted if necessary. Various GAO decisions have confirmed that: In reviewing protests of an agency’s evaluation, [GAO] does not reevaluate proposals, rather, we review

6215-484: The LHC is limited by its ability to steer the particles without them going adrift. This limit is theorized to occur at 14 TeV. However, since the particle momentum increases during acceleration, it is necessary to turn up the magnetic field B in proportion to maintain constant curvature of the orbit. In consequence, synchrotrons cannot accelerate particles continuously, as cyclotrons can, but must operate cyclically, supplying particles in bunches, which are delivered to

6328-485: The Super Collider for its high costs and poor management by officials in charge of it. The Inspector General investigated $ 500,000 in questionable expenses over three years, including $ 12,000 for Christmas parties, $ 25,000 for catered lunches, and $ 21,000 for the purchase and maintenance of office plants. The report also concluded that there was inadequate documentation for $ 203 million in project spending, or 40% of

6441-402: The Super Collider. An extensive U.S. Department of Energy review was also done during the mid-1980s. Seventeen shafts were sunk and 23.5 km (14.6 mi) of tunnel were bored by late 1993. During the design and the first construction stage, a heated debate ensued about the high cost of the project. In 1987, Congress was told the project could be completed for $ 4.4 billion, and it gained

6554-609: The Tevatron, LEP , and LHC may deliver the particle bunches into storage rings of magnets with a constant magnetic field, where they can continue to orbit for long periods for experimentation or further acceleration. The highest-energy machines such as the Tevatron and LHC are actually accelerator complexes, with a cascade of specialized elements in series, including linear accelerators for initial beam creation, one or more low energy synchrotrons to reach intermediate energy, storage rings where beams can be accumulated or "cooled" (reducing

6667-687: The U.S. are SSRL at SLAC National Accelerator Laboratory , APS at Argonne National Laboratory, ALS at Lawrence Berkeley National Laboratory , and NSLS-II at Brookhaven National Laboratory . In Europe, there are MAX IV in Lund, Sweden, BESSY in Berlin, Germany, Diamond in Oxfordshire, UK, ESRF in Grenoble , France, the latter has been used to extract detailed 3-dimensional images of insects trapped in amber. Free-electron lasers (FELs) are

6780-552: The additional cost caused by not using existing physical and human infrastructure at Fermilab in Illinois range from $ 495 million to $ 3.28 billion. Leaders hoped to get financial support from Europe, Canada, Japan, Russia, and India. This was hindered by promotion of the project as promoting American superiority. European funding remained at CERN , which was already working on the Large Hadron Collider . India pledged $ 50 million, but talks with Japan floundered over trade tensions in

6893-824: The agency in "taking corrective action in the face of a clearly meritorious protest". The GAO confirmed in 2014 that its jurisdiction includes investigation of protests raising allegations of agency violation of the Procurement Integrity Act . After the closing of the Office of Technology Assessment (OTA) in 1995, Congress directed the GAO to conduct a technology assessment (TA) pilot program. Between 2002 and 2005, three reports were completed–-use of biometrics for border security, cyber security for critical infrastructure protection , and technologies for protecting structures in wildland fires. The GAO reports and technology assessments, which are made available to

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7006-564: The automobile industry. A US-Japanese trade mission where SSC funding was supposed to be discussed ended in the George H. W. Bush vomiting incident . Congress began appropriating annual funding for the project. In 1992, it was opposed by the majority of the House of Representatives (231-181), but was included in the final reconciled budget due to support in the Senate (62-32). Early in 1993, a group supported by funds from project contractors organized

7119-494: The beam is handled independently by specialized quadrupole magnets , while the acceleration itself is accomplished in separate RF sections, rather similar to short linear accelerators. Also, there is no necessity that cyclic machines be circular, but rather the beam pipe may have straight sections between magnets where beams may collide, be cooled, etc. This has developed into an entire separate subject, called "beam physics" or "beam optics". More complex modern synchrotrons such as

7232-532: The cancellation: rising cost estimates (to $ 12bn); poor management by physicists and Department of Energy officials; the end of the need to prove the supremacy of American science with the collapse of the Soviet Union and the end of the Cold War ; belief that many smaller scientific experiments of equal merit could be funded for the same cost; Congress's desire to generally reduce spending (the United States

7345-428: The cash deficit is $ 1,294 billion. The most recent GAO strategic plan, for 2018–2023, sets out four goals, namely: The Forensic Audits and Investigative Service (FAIS) team provides Congress with high-quality forensic audits and investigations of fraud, waste, and abuse; other special investigations; and security and vulnerability assessments. Its work cuts across a diverse array of government programs administered by

7458-460: The center of the circle, it continuously radiates towards the tangent of the circle. This radiation is called synchrotron light and depends highly on the mass of the accelerating particle. For this reason, many high energy electron accelerators are linacs. Certain accelerators ( synchrotrons ) are however built specially for producing synchrotron light ( X-rays ). Since the special theory of relativity requires that matter always travels slower than

7571-613: The disks is a ferrite toroid. A voltage pulse applied between the two disks causes an increasing magnetic field which inductively couples power into the charged particle beam. The linear induction accelerator was invented by Christofilos in the 1960s. Linear induction accelerators are capable of accelerating very high beam currents (>1000 A) in a single short pulse. They have been used to generate X-rays for flash radiography (e.g. DARHT at LANL ), and have been considered as particle injectors for magnetic confinement fusion and as drivers for free electron lasers . The Betatron

7684-435: The electrons can pass through. The electron beam passes through the pillar via one of these holes and then travels through a hole in the wall of the cavity, and meets a bending magnet, the beam is then bent and sent back into the cavity, to another hole in the pillar, the electrons then again go across the pillar and pass though another part of the wall of the cavity and into another bending magnet, and so on, gradually increasing

7797-499: The electrons moving at nearly the speed of light in a relatively small radius orbit. In a linear particle accelerator (linac), particles are accelerated in a straight line with a target of interest at one end. They are often used to provide an initial low-energy kick to particles before they are injected into circular accelerators. The longest linac in the world is the Stanford Linear Accelerator , SLAC, which

7910-461: The energy of the beam until it is allowed to exit the cavity for use. The cylinder and pillar may be lined with copper on the inside. Ernest Lawrence's first cyclotron was a mere 4 inches (100 mm) in diameter. Later, in 1939, he built a machine with a 60-inch diameter pole face, and planned one with a 184-inch diameter in 1942, which was, however, taken over for World War II -related work connected with uranium isotope separation ; after

8023-531: The enthusiastic support of Speaker Jim Wright of nearby Fort Worth, Texas . A recurring argument was the contrast with NASA 's contribution to the International Space Station (ISS), a similar dollar amount. Critics of the project ( Congressmen representing other US states and scientists working in non-SSC fields who felt the money would be better spent on their own fields) argued that the US could not afford both of them. Estimates of

8136-538: The equivalent of about 5 billion US dollars to build. The total operating budget of CERN runs to about $ 1 billion per year. The Large Hadron Collider became operational in August 2008. In a 2021 interview, Schwitters speculated that, had the project been completed, it would have led to the discovery of the Higgs boson particle 10 years before its eventual discovery in Switzerland and attracted an equivalent number of visitors to North Texas as CERN's 120,000 per year. After

8249-537: The evaluation to determine if it was reasonable, consistent with the solicitation’s evaluation scheme and procurement statutes and regulations, and adequately documented. There is a facility within the Bid Protest Regulations for the GAO to recommend reimbursement of a bidder's protest costs if the procuring agency takes corrective action in response to a protest. The circumstances justifying bid protest cost reimbursement must involve "undue delay" by

8362-430: The face of some opposition from the local community. The buildings in the facility, which had become prime spots for thieves and drug parties, were renovated and were re-opened in 2013 by Magnablend. The facility makes a range of oil field products for the energy service industry. In Season 3, Episode 15 of Beavis and Butt-Head , titled "Citizen Butt-Head" which aired on October 18, 1993, the day before Congress cancelled

8475-543: The fact that those fields were more likely to produce applications with technological and economic benefits. Steven Weinberg , a Nobel laureate in Physics, placed the cancellation of the SSC in the context of a bigger national and global socio-economic crisis, including a general crisis in funding for science research and for the provision of adequate education, healthcare, transportation and communication infrastructure, and criminal justice and law enforcement. Leon Lederman,

8588-568: The findings, conclusions, and recommendations of its reports. Members of Congress also frequently cite the GAO's work in statements to the press, congressional hearings, and floor debates on proposed legislation. In 2007 the Partnership for Public Service ranked the GAO second on its list of the best places to work in the federal government and Washingtonian magazine included the GAO on its 2007 list of great places to work in Washington,

8701-409: The first accelerators used simple technology of a single static high voltage to accelerate charged particles. The charged particle was accelerated through an evacuated tube with an electrode at either end, with the static potential across it. Since the particle passed only once through the potential difference, the output energy was limited to the accelerating voltage of the machine. While this method

8814-423: The fiscal future of the United States, GAO's role in the federal bid protest process, and critical issues for congressional consideration related to improving the nation's image abroad. The GAO is headquartered in Washington, D.C. and maintains an additional 11 field offices around the country. Each field office contains several mission teams, but not every mission team is represented at each field office. The GAO

8927-578: The funding for the Super Collider, an honor student of Highland Highschool is overheard rehearsing his question for President Bill Clinton in which he asks: "Given the budget deficit, do you think the Super Collider is really necessary at this time?" "Supercollider," a 1993 song by the Boston-based alternative band Tribe , describes the point of view of a scientist hired to help build the (then-uncancelled) project. John G. Cramer 's 1997 hard science fiction novel Einstein's Bridge centers around

9040-415: The host state of Texas, the rest by the Department of Energy), the House of Representatives rejected funding on October 19, 1993, and Senate negotiators failed to restore it. Following Rep. Jim Slattery 's successful orchestration in the House, President Clinton signed the bill that finally canceled the project on October 30, 1993, stating regret at the "serious loss" for science. Many factors contributed to

9153-411: The magnet aperture required and permitting tighter focusing; see beam cooling ), and a last large ring for final acceleration and experimentation. Circular electron accelerators fell somewhat out of favor for particle physics around the time that SLAC 's linear particle accelerator was constructed, because their synchrotron losses were considered economically prohibitive and because their beam intensity

9266-412: The magnetic field does not cover the entire area of the particle orbit as it does for a cyclotron, so several necessary functions can be separated. Instead of one huge magnet, one has a line of hundreds of bending magnets, enclosing (or enclosed by) vacuum connecting pipes. The design of synchrotrons was revolutionized in the early 1950s with the discovery of the strong focusing concept. The focusing of

9379-487: The massive facility. The SSC's planned collision energy of 2 x 20 = 40 TeV was roughly three times that of the 2 x 6.8 = 13.6 TeV (as of 2023) of its European counterpart, the Large Hadron Collider (LHC) at CERN in Geneva . However, the planned luminosity was only one tenth of the design luminosity of the LHC. Although some claimed that the SSC cost was largely due to the massive civil engineering project of digging

9492-399: The money spent up to that point. In 1993 U.S. President Bill Clinton tried to prevent the cancellation by asking Congress to continue "to support this important and challenging effort" through completion because "abandoning the SSC at this point would signal that the United States is compromising its position of leadership in basic science". After $ 2 billion had been spent ($ 400 million by

9605-481: The most basic inquiries into the dynamics and structure of matter, space, and time, physicists seek the simplest kinds of interactions at the highest possible energies. These typically entail particle energies of many GeV , and interactions of the simplest kinds of particles: leptons (e.g. electrons and positrons ) and quarks for the matter, or photons and gluons for the field quanta . Since isolated quarks are experimentally unavailable due to color confinement ,

9718-517: The need for a huge magnet of large radius and constant field over the larger orbit demanded by high energy. The second approach to the problem of accelerating relativistic particles is the isochronous cyclotron . In such a structure, the accelerating field's frequency (and the cyclotron resonance frequency) is kept constant for all energies by shaping the magnet poles so to increase magnetic field with radius. Thus, all particles get accelerated in isochronous time intervals. Higher energy particles travel

9831-544: The nine-year tenure of the seventh comptroller general, David M. Walker . On September 19, 2007, GAO analysts voted by a margin of two to one (897–445), in a 75% turnout, to establish the first union in the GAO's 86-year history. The analysts voted to affiliate with the International Federation of Professional and Technical Engineers (IFPTE), a member union of the AFL–CIO . There are more than 1,800 analysts in

9944-423: The office. The GAO's auditors conduct not only financial audits, but also engage in a wide assortment of performance audits. Over the years, the GAO has been referred to as "The Congressional Watchdog" and "The Taxpayers' Best Friend" for its frequent audits and investigative reports that have uncovered waste and inefficiency in government. News media often draw attention to the GAO's work by publishing stories on

10057-455: The outer edge of the structure. Synchrocyclotrons have not been built since the isochronous cyclotron was developed. To reach still higher energies, with relativistic mass approaching or exceeding the rest mass of the particles (for protons, billions of electron volts or GeV ), it is necessary to use a synchrotron . This is an accelerator in which the particles are accelerated in a ring of constant radius. An immediate advantage over cyclotrons

10170-412: The particles and a single large dipole magnet to bend their path into a circular orbit. It is a characteristic property of charged particles in a uniform and constant magnetic field B that they orbit with a constant period, at a frequency called the cyclotron frequency , so long as their speed is small compared to the speed of light c . This means that the accelerating D's of a cyclotron can be driven at

10283-449: The potential is used twice to accelerate the particles, by reversing the charge of the particles while they are inside the terminal. This is possible with the acceleration of atomic nuclei by using anions (negatively charged ions ), and then passing the beam through a thin foil to strip electrons off the anions inside the high voltage terminal, converting them to cations (positively charged ions), which are accelerated again as they leave

10396-403: The president, and the president may request that the commission recommend additional individuals. The president then selects an individual from those recommended to nominate as the new comptroller general. The president's nomination must be confirmed by the Senate's Committee on Homeland Security & Governmental Affairs before being voted on by the full Senate. The current comptroller general

10509-429: The project was canceled, the main site was deeded to Ellis County, Texas , and the county tried numerous times to sell the property. The property was sold in August 2006 to an investment group, Collider Data Center, LLC, led by the late J.B. Hunt . In 2009, Collider Data Center had contracted with GVA Cawley to market the site as a data center . In 2012, chemical company Magnablend bought the property and facilities in

10622-605: The project. A Hole In Texas is a 2004 novel by Herman Wouk , which describes the adventures of a high-energy physicist following the surprise announcement that a Chinese physicist had discovered the long-sought Higgs boson . Parts of the plot are based on the aborted Superconducting Super Collider project. On the January 21, 2021, episode of Young Sheldon the supercollider is mentioned when Sheldon Cooper 's ( Iain Armitage ) mentor Dr. John Sturgis ( Wallace Shawn ) gets

10735-419: The project. They argued that, although the SSC would certainly conduct high-quality research, it was not the only way to acquire new fundamental knowledge, as some of its supporters claimed, and so was unreasonably expensive. Scientific critics of the SSC pointed out that basic research in other areas, such as condensed matter physics and materials science , was underfunded compared to high energy physics, despite

10848-401: The public, have become essential vehicles for understanding science and technology (S&T) implications of policies considered by the Congress. Since 2008, Congress has established a permanent TA function within the GAO. This new operational role augments GAO's performance audits related to S&T issues, including effectiveness and efficiency of U.S. federal programs. In 2010, the GAO joined

10961-561: The quality of audit effort, and the characteristics of professional and meaningful audit reports. In 1992, the GAO hosted the XIV INCOSAI , the fourteenth triennial convention of the International Organization of Supreme Audit Institutions (INTOSAI). The GAO is a United States government electronic data provider, as all of its reports are available on its website, except for certain reports whose distribution

11074-434: The secondary winding in a transformer, due to the changing magnetic flux through the orbit. Achieving constant orbital radius while supplying the proper accelerating electric field requires that the magnetic flux linking the orbit be somewhat independent of the magnetic field on the orbit, bending the particles into a constant radius curve. These machines have in practice been limited by the large radiative losses suffered by

11187-571: The simplest available experiments involve the interactions of, first, leptons with each other, and second, of leptons with nucleons , which are composed of quarks and gluons. To study the collisions of quarks with each other, scientists resort to collisions of nucleons, which at high energy may be usefully considered as essentially 2-body interactions of the quarks and gluons of which they are composed. This elementary particle physicists tend to use machines creating beams of electrons, positrons, protons, and antiprotons , interacting with each other or with

11300-405: The simplest nuclei (e.g., hydrogen or deuterium ) at the highest possible energies, generally hundreds of GeV or more. The largest and highest-energy particle accelerator used for elementary particle physics is the Large Hadron Collider (LHC) at CERN , operating since 2009. Nuclear physicists and cosmologists may use beams of bare atomic nuclei , stripped of electrons, to investigate

11413-426: The speed of light in vacuum , in high-energy accelerators, as the energy increases the particle speed approaches the speed of light as a limit, but never attains it. Therefore, particle physicists do not generally think in terms of speed, but rather in terms of a particle's energy or momentum , usually measured in electron volts (eV). An important principle for circular accelerators, and particle beams in general,

11526-471: The structure, interactions, and properties of the nuclei themselves, and of condensed matter at extremely high temperatures and densities, such as might have occurred in the first moments of the Big Bang . These investigations often involve collisions of heavy nuclei – of atoms like iron or gold  – at energies of several GeV per nucleon . The largest such particle accelerator

11639-507: The terminal. The two main types of electrostatic accelerator are the Cockcroft–Walton accelerator , which uses a diode-capacitor voltage multiplier to produce high voltage, and the Van de Graaff accelerator , which uses a moving fabric belt to carry charge to the high voltage electrode. Although electrostatic accelerators accelerate particles along a straight line, the term linear accelerator

11752-573: The war it continued in service for research and medicine over many years. The first large proton synchrotron was the Cosmotron at Brookhaven National Laboratory , which accelerated protons to about 3  GeV (1953–1968). The Bevatron at Berkeley, completed in 1954, was specifically designed to accelerate protons to enough energy to create antiprotons , and verify the particle–antiparticle symmetry of nature, then only theorized. The Alternating Gradient Synchrotron (AGS) at Brookhaven (1960–)

11865-476: The world. There are two basic classes of accelerators: electrostatic and electrodynamic (or electromagnetic) accelerators. Electrostatic particle accelerators use static electric fields to accelerate particles. The most common types are the Cockcroft–Walton generator and the Van de Graaff generator . A small-scale example of this class is the cathode-ray tube in an ordinary old television set. The achievable kinetic energy for particles in these devices

11978-639: Was Roy Schwitters , a physicist at the University of Texas at Austin . Department of Energy administrator Louis Ianniello served as its first project director, followed by Joe Cipriano, who came to the SSC Project from the Pentagon in May 1990. After 22.5 km (14 mi) of tunnel had been bored and about US$ 2 billion spent, the project was canceled by the US Congress in 1993. The supercollider

12091-551: Was established as the General Accounting Office by the Budget and Accounting Act of 1921. The act required the head of the GAO to: investigate, at the seat of government or elsewhere, all matters relating to the receipt, disbursement, and application of public funds, and shall make to the President ... and to Congress ... reports [and] recommendations looking to greater economy or efficiency in public expenditures. According to

12204-568: Was formally discussed in the 1984 National Reference Designs Study, which examined the technical and economic feasibility of a machine with the design energy of 20 TeV per proton. Early in 1983, HEPAP ( High-Energy Physics Advisory Panel ) formed the New Facilities for the US High-Energy Physics Program subpanel. Led by Stanford University physicist Stanley Wojcicki , and charged with making recommendations “for

12317-648: Was lower than for the unpulsed linear machines. The Cornell Electron Synchrotron , built at low cost in the late 1970s, was the first in a series of high-energy circular electron accelerators built for fundamental particle physics, the last being LEP , built at CERN, which was used from 1989 until 2000. A large number of electron synchrotrons have been built in the past two decades, as part of synchrotron light sources that emit ultraviolet light and X rays; see below. Some circular accelerators have been built to deliberately generate radiation (called synchrotron light ) as X-rays also called synchrotron radiation, for example

12430-620: Was organized in California at the Lawrence Berkeley Laboratory , which became the gathering place for physicists to come and support the SSC design effort. In the mid-1980s, many leading high-energy physicists, including theorist J. David Jackson of Berkeley, Chris Quigg of Fermilab, Maury Tigner of Cornell, Stanley Wojcicki , as well as Lederman , Chicago’s James Cronin , Harvard theorist Sheldon Glashow , and Roy Schwitters , continued their efforts to promote

12543-529: Was running a $ 255bn budget deficit); the reluctance of Texas Governor Ann Richards ; and President Bill Clinton 's initial lack of support for a project began during the administrations of Richards's predecessor, Bill Clements , and Clinton's predecessors, Ronald Reagan and George H. W. Bush . The project's cancellation was also eased by opposition from within the scientific community. Prominent condensed matter physicists, such as Philip W. Anderson and Nicolaas Bloembergen , testified before Congress opposing

12656-414: Was the synchrocyclotron , which accelerates the particles in bunches. It uses a constant magnetic field B {\displaystyle B} , but reduces the accelerating field's frequency so as to keep the particles in step as they spiral outward, matching their mass-dependent cyclotron resonance frequency. This approach suffers from low average beam intensity due to the bunching, and again from

12769-502: Was the first large synchrotron with alternating gradient, " strong focusing " magnets, which greatly reduced the required aperture of the beam, and correspondingly the size and cost of the bending magnets. The Proton Synchrotron , built at CERN (1959–), was the first major European particle accelerator and generally similar to the AGS. The Stanford Linear Accelerator , SLAC, became operational in 1966, accelerating electrons to 30 GeV in

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