Particle physics: Stanford wins a B Factory.Mothball moth·ball
1. A marble-sized ball, originally of camphor but now of naphthalene, stored with clothes to repel moths.
a. since 1990, the Positron-Electron Project (PEP) particle accelerator at the Stanford Linear Accelerator Center
The Stanford Linear Accelerator Center (SLAC) is a United States Department of Energy National Laboratory operated by Stanford University under the programmatic direction of the U.S. (SLAC SLAC Stanford Linear Accelerator Center
SLAC Student Labor Action Coalition
SLAC Scapholunate Advanced Collapse (wrist disorder)
SLAC Salt Lake Acting Company (Utah)
SLAC Student Learning Assistance Center ) had outlived its usefulness. But last week, its fortunes were revived when the Department of Energy selected SLAC as the site of a new research facility known as the B Factory.
Designed to mass-produce large quantities of subatomic particles known as B mesons This is a list of mesons; it is not comprehensive.this is a stub
Particle Symbol Anti-
Makeup Spin and parity Rest mass
MeV/c² S C B Mean lifetime
s Principal decays Notes
Pion via collisions between electrons and positrons (the oppositely charged, antimatter antimatter: see antiparticle.
Substance composed of elementary particles having the mass and electric charge of ordinary matter (such as electrons and protons) but for which the charge and related magnetic properties are opposite in sign. counterparts of electrons), the B Factory will be installed in the existing tunnel occupied by the PEP colliding-beam storage ring.
"This facility will be a crucial element in a balanced U.S. high-energy physics program and will ensure continued U.S. leadership on the electron frontier," says Burton Richter, SLAC director.
Construction of the B Factory would allow particle physicists to study in great detail a subatomic subatomic /sub·atom·ic/ (-ah-tom´ik) of or pertaining to the constituent parts of an atom.
1. Of or relating to the constituents of the atom.
2. process -- known as CP violation -- that may be responsible for the overwhelming perponderance of matter over antimatter in the universe. Theorists suggest that the universe started out with equal amounts of matter and antimatter and that somehow a minuscule anomaly at the very beginning skewed this distribution toward matter.
Discovered in 1977, B mesons consists of a bottom quark paired with an anti-up or an andi-down quark. When these particles decay into other particles, a small fraction doesn't follow the usual rule that leaves parity, a characteristic of particle interactions, unchanged. Thus, it's possible in these interactions to distinguish between our world and its mirror image, even when particles are replaced by their antiparticles. By measuring the decays of large numbers of B mesons, physicists can study these rare, CP-violating events more readily.
In the B Factory, collisions between electrons and positrons in beams having a total energy of 10.6 billion electron-volts produced copious quantities of subatomic particles called upsilons. These particles, in turn, decay to produce B and anti-B meson meson (mē`zŏn) [Gr.,=middle (i.e., middleweight)], class of elementary particles whose masses are generally between those of the lepton class of lighter particles and those of the baryon class of heavier particles. pairs. By using electron and positron beams of unequal energies, researchers can examine the decays of B and anti-B mesons separately.
Two groups vied to host the B Factory. SLAC worked with the Lawrence Berkeley Laboratory and the Lawrence Livermore National Laboratory Lawrence Livermore National Laboratory: see Lawrence Berkeley National Laboratory.
(body) Lawrence Livermore National Laboratory - (LLNL) A research organaisatin operated by the University of California under a contract with the US Department of Energy. on a proposal to upgrade and modify its PEP accelerator to hunt for B mesons. Cornell University, which already has an accelerator with a first-rate detector for tracking B mesons, submitted its proposal at the same time. After several years of reviews by various panels and committees, SLAC won the competition.
With the cost of its PEP upgrade put at $177 million, the SLAC proposal also calls for an additional $60 million to build a detector. A significant proportion of the funding for this detector may come from foreign sources. If construction starts this year, the SLAC B Factory should be open for research in 1998.
Aimed at the elucidation of CP violation and matter-antimatter asymmetry, the B Factory complements several other particle physics projects. At the Fermi National Accelerator Laboratory Fermi National Accelerator Laboratory (Fermilab), physical science research center located near Batavia, Ill., est. 1968 as the National Accelerator Laboratory, renamed 1974 in honor of Enrico Fermi. It was built on the site of the former village of Weston. in Batavia, Ill., physicists are searching for the top quark -- the only one of the six types of quarks that remains undetected (SN: 4/24/93, p.264). At the Superconducting Super Collider
The Superconducting Super Collider (SSC) was a ring particle accelerator which was planned to be built in the area around Waxahachie, Texas. (SSC), under construction in Texas, researchers will study high-energy collisions between protons and antiprotons to gain insights into the origin of mass.
Construction of the B Factory can start this year if Congress appropriates $36 million for this purpose in the fiscal 1994 budget. A conference committee of House and Senate members must also decide the fate of the SSC. Last June, the House voted by a large margin to kill the project (SN: 7/17/93, p.45). Late last month, however, the Senate decided by a 57-42 vote to continue funding the SSC.