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On January 11, 1994, Secretary of Energy Hazel O'Leary attended
the inauguration of the B Factory construction project at
the Stanford Linear Accelerator Center. The new facility is designed
to produce copious quantities of B mesons and anti-B mesons, with
the aim of enabling physicists to test certain aspects of the Standard
Model of particle physics. The ultimate goal is to gain insight
into one of the central mysteries of cosmology, namely, that of
why we observe such a preponderance of matter over antimatter in
the universe today. Current theory holds that matter and antimatter
existed in equal quantities at the moment of the Big Bang. Given
that initial condition, we should not observe a universe composed
largely of matter. Instead, one of two conditions should obtain
today: Either matter and antimatter should have annihilated each
other, or antimatter should exist in quantities roughly equal to
those of matter. The current explanation for the matter-dominated
universe is that there was some small preference for matter over
antimatter in the original process of creation. If we can assume
that physical processes have operated consistently since the Big
Bang, then the key to understanding the preference for matter creation
must lie in the phenomenon of charge-parity (CP) violation. Given
the current state of their art, physicists believe that CP violation
is best studied by examining the decay of B mesons and their antiparticles,
an investigation that requires the production of billions of B mesons
and anti-B mesons. Hence the need for a B Factory.
The new B Factory will actually be an upgrade of SLAC's
existing PEP (positron-electron project) facility. The construction
project will entail renovating the existing high-energy PEP storage
ring, adding a new low-energy storage ring inside the same PEP
tunnel, and creating and installing a detector designed expressly
for CP-violation studies. Data collection is scheduled to commence
in the spring of 1999. After that point, the project is expected
to generate approximately 100 terabytes of raw, reconstructed,
and Monte Carlo data each year. Large amounts of this data must
be distributed within a collaboration that includes nearly 400
physicists representing 75 institutions in nine countries (the
U.S., Canada, the UK, France, Italy, Germany, Russia, the PRC,
and Taiwan). Wide-area networking will play a crucial role in
this widely-distributed enterprise. Essential interactive services
will include e-mail, NetNews and World Wide Web access, videoconferencing
(workstation-based as well as conference-room-based), and remote
log-in using X windows. Remote operation of parts of the detector
system will be made available to some external sites for problem
diagnosis and debugging. In addition, distributed software development
will require a system for coordinating code development and automating
its distribution. Finally, the prompt data analysis needed to
support timely publication of experimental results will require
the transfer of large data sets between institutions. Data transfers
on this scale could easily overwhelm today's network capacities.
However, they also offer the promise of a data transport medium
that is faster, more reliable, and less labor-intensive than traditional
tape distribution.
Above, B Factory layout; inset, Hazel O'Leary at B Factory
groundbreaking in January of 1994
Return to the beginning of this section, High
Energy Physics
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