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Fermilab
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Fermi National Accelerator Laboratory (Fermilab), located in Batavia near Chicago, Illinois, is a U.S. Department of Energy national laboratory specializing in high-energy particle physics.
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Fermi National Accelerator Laboratory (Fermilab), located in Batavia near Chicago, Illinois, is a U.S. Department of Energy national laboratory specializing in high-energy particle physics. As of January 1, 2007, Fermilab is operated by Fermi Research Alliance, LLC, a joint venture of the University of Chicago and the Universities Research Association (URA). URA is a consortium of 91 leading research oriented universities primarily in the United States, with members also in Canada, Japan, and Italy. Fermilab is a part of the Illinois Technology and Research Corridor.
Fermilab's Tevatron is a landmark particle accelerator; at in circumference, it is the world's second largest energy particle accelerator (the CERN LHC is 27 kilometres in circumference). In 1995, both the CDF and D0 (detectors which utilize the Tevatron) experiments announced the discovery of the top quark. In addition to high energy collider physics, Fermilab is also host to a number of smaller fixed target experiments and neutrino experiments, such as MiniBooNE (Mini Booster Neutrino Experiment), SciBooNE (SciBar Booster Neutrino Experiment) and MINOS (Main Injector Neutrino Oscillation Search). The MiniBooNE detector is a diameter sphere which contains 800 tons of mineral oil lined with 1520 individual phototube detectors. An estimated 1 million neutrino events are recorded each year. SciBooNE is the newest neutrino experiment at Fermilab; it sits in the same neutrino beam as MiniBooNE but has fine-grained tracking capabilities. The MINOS experiment uses Fermilab's NuMI (Neutrinos at the Main Injector) beam, which is an intense beam of neutrinos that travels 735km through the Earth to the Soudan Mine in Minnesota.
In the public realm, Fermilab is host to many cultural events, not only public science lectures and symposia, but classical and contemporary music concerts, folk dancing and arts galleries, when the Homeland Security Advisory System permits. Currently the site is open to all visitors from dawn to dusk who present valid photo identification.
A small herd of American bison, started at the lab's founding, lives on the grounds symbolizing Fermilab's presence on the frontier of physics and its connection to the American prairie.
Asteroid 11998 Fermilab is named in honor of the laboratory.
History
Weston, Illinois was a community next to Batavia voted out of existence by its village board in 1966 to provide a site for Fermilab.
The laboratory was founded in 1967 as the National Accelerator Laboratory; it was renamed in honor of Enrico Fermi in 1974. The lab's first director was Robert Rathbun Wilson. Many of the unique sculptures on the site are of his creation. He is attributed as being responsible for it being finished ahead of time and under budget. The high rise laboratory building located on the site, the unique shape of which has become the symbol for Fermilab, is named in his honor, and is the center of activity on the campus.
After Dr. Wilson stepped down in 1978 to protest the lack of funding for the lab, Dr. Leon M. Lederman took on the job. It was under his guidance that the original accelerator was replaced with the Tevatron accelerator, an accelerator capable of colliding a proton and an antiproton at a combined energy of 1.96 TeV. Dr. Lederman stepped down in 1988 and remains Director Emeritus. The on-site science education center was named in his honor.
From 1988 to 1998, the lab was run by Dr. John Peoples. From that time until June 30, 2005, the lab was run by Michael S. Witherell. On November 19, 2004 Piermaria Oddone, formerly of the Lawrence Berkeley National Laboratory in California, was announced as Fermilab's newest Director. Oddone began his term as director July 1, 2005.
Fermilab is one of the potential sites for the proposed International Linear Collider, though the 2008 omnibus budget bill that has passed Congress makes it unlikely that the facility will be located at Fermilab.
Accelerators
The first stage in the acceleration process takes place in the Cockcroft-Walton generator. It involves taking hydrogen gas and turning it into H- ions by introducing it into a container lined with molybdenym electrodes: a matchbox-sized, oval-shaped cathode and a surrounding anode, separated by 1 mm and held in place by glass ceramic insulators. A magnetron is used to generate a plasma to form H- near the metal surface. A 750 keV electrostatic field is applied by the Cockcroft-Walton generator, and the ions are accelerated out of the container. The next step is the linear accelerator (or linac), which accelerates the particles to 400 million electron volts (MeV), or about 70% of the speed of light. Right before entering the next accelerator, the H- ions pass through a carbon foil, becoming H+ ions (protons).
The next step is the booster ring. The booster ring is a circular accelerator that uses magnets to bend beams of protons in a circular path. The protons coming from the Linac travel around the Booster about 20,000 times so that they repeatedly experience electric fields. With each revolution the protons pick up more energy, leaving the Booster with 8 billion electron volts (GeV). The Main Injector is the next link in the accelerator chain. Completed in 1999, it has become Fermilab's "particle switchyard" with three functions: it accelerates protons, it delivers protons for antiproton production, and it accelerates antiprotons coming from the antiproton Source. The final accelerator is the Tevatron. The four-mile-long Tevatron with its superconducting magnets is the second most powerful particle accelerator in the world (LHC being the most powerful). Traveling at almost the speed of light, protons and antiprotons circle the Tevatron in opposite directions. Physicists co-ordinate the beams so that they collide at the centers of two 5,000-ton detectors DZero and CDF inside the Tevatron tunnel at energies of 1.96 trillion electron volts (TeV), revealing the conditions of matter in the early universe and its structure at the smallest scale.
Experiments
- Tevatron proton-antiproton collider: D0 and Collider Detector at Fermilab
- MiniBooNE: Mini Booster Neutrino Experiment
- Sciboone: SciBar Booster Neutrino Experiment
- MINOS: Main Injector Neutrino Oscillation Search
- MINER?A: Main INjector ExpeRiment with ?s on As
- NO?A: NuMI Off-axis ?e Appearance (proposed, but given no funding by Congress)
- MIPP: Main Injector Particle Production
Architecture
Dr. Wilson maintained an influence over design and construction such that the aesthetic complexion of the site would not be diluted by a collection of concrete block buildings. The design of the administrative building (Wilson Hall) harks back to St. Pierre's Cathedral in Beauvais, France, and several of the buildings and sculptures within the Fermilab reservation represent various mathematical constructs as part of their structure.
The Archimedean Spiral is the defining shape of several pumping stations as well as the building housing the MINOS experiment. The reflecting pond at Wilson Hall also showcases a 32-foot tall hyperbolic obelisk, designed by Dr. Wilson. Some of the high voltage transmission lines carrying power through the laboratory's land are built to echo the Greek letter p. One can also find structural examples of the DNA double-helix spiral and a nod to the geodesic sphere.
Several large pieces of sculpture found on Fermilab and designed by Wilson include Tractricious, a free-standing arrangement of steel tubes near the Industrial Complex constructed from parts and materials recycled from the Tevatron collider, and the soaring Broken Symmetry, which greets those entering the campus via the Pine Street entrance. Crowning the Ramsey Auditorium is a representation of the Möbius strip with a diameter of more than eight feet.
Gender issues at Fermilab
Fermilab won the 2006 Golden Family Award from the Society of Women Engineers. Fermilab offers equal employment; women represent more than 40% of the work force and most of them are spouses or daughters of scientists and physicists. Golden Family Award stated, "For outstanding support of family issues your facilities, your benefits, your programs, and your approach encourage balance for employees and their families[...]".
There are two cases of gender bias in the Fermilab workplace: the separate federal lawsuits filed by Katharine Weber and Irene Hofmann. Both formerly worked at Fermilab, and both alleged they were retaliated against after complaining of repeated episodes of sexual harassment and discrimination to the Fermilab Equity Office. A summary judgment was granted in favor of URA on both of Weber's claims. Weber filed an appeal at the end of April, 2008 and the case is still ongoing.
There is also evidence of widespread endemic gender bias at the laboratory; in April, 2008 a detailed statistical study revealed significant gender inequities in conference presentations allocated by the laboratory to postdoctoral research scientists based at Fermilab. Based on productivity, males received three times the conference presentations relative to their female peers. Conference presentation allocations are important to the career advancement prospects of young particle physicists.
Current developments
Financial situation
The Fermilab budget has been continuously below inflation over the last several years, and Fermilab failed to attract more funding sources and this resulted in reducing staff levels (by 100 in 2005). The new director of the lab and the new management are working hard to bring the International Linear Collider (ILC) to Fermilab. However, the decision by Congress to fund the ILC at only a quarter of the requested $60 million significantly reduces the chances that Fermilab or any other U.S. research facility will host the ILC. Fermilab's financial situation is dire, and on December 20, 2007 director Piermaria Oddone announced the planned layoffs of 10% of Fermilab's staff.
New management
On November 1, 2006, the Department of Energy announced that the Fermi Research Alliance, LLC (FRA) will manage Fermilab for five years starting January 1, 2007. The FRA is a partnership between the Universities Research Association (URA) and the University of Chicago. Based on its performance, the FRA may be entitled to renew this contract without competition for up to 20 years.
CERN
As of 2008, the Tevatron is no longer the highest energy collider in the world. In September 2008 CERN made its Large Hadron Collider operational. It is expected that the initial center-of-mass of 10 TeV, with full energy to follow in 2009. This particle accelerator has a 27km circumference, and will accelerate particles to a total collision energy of 14 TeV, 7 times the energy at Fermilab. Although Fermilab will continue to play an important role in the future of physics, as of 2008 it lost its prestigious title of the world's highest energy collider.
Failure of magnets
On March 27, 2007, a magnet designed and built by Fermilab for CERN's Large Hadron Collider suffered a catastrophic failure. The 14-meter long quadrupole magnet broke after supports that held the magnet in place inside a cylinder of liquid helium snapped. The solution to this failure was developed within 3 months. Full current of 11.4 kilo-amps was achieved in one of these repaired magnets on April 24, 2008.
New Particle Discovery
It was announced on September 3, 2008 that a new particle was discovered at the DZero Experiment of Fermilab. Known as the Omega-sub-b (Ob), it is made up of three quarks and is in the same family of particles as the much more common proton. As it is made up of two strange quarks and a bottom quark, it has also been dubbed the "doubly strange" particle. This discovery not only helps to complete the "periodic table of the baryons" but also offers insight into how quarks form matter.
See also
External links
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