 You might have
noticed that RHIC's magnets look different from those at the
AGS.
That's because RHIC magnets are superconducting, using niobium
titanium wire to carry the electrical current that powers the magnets. When
the special wire at left is cooled to minus 451 degrees Fahrenheit, electricity
flows through it with almost no resistance, creating a
tremendously powerful magnetic field. This is the technology that
allows RHIC to accelerate heavy ions to higher energies than any other
machine in the world.
 Brookhaven
magnet experts designed all 1,740 RHIC magnets. Many
of the magnets were manufactured by the Northrop Grumman Corp. in Bethpage,
Long Island. Shown at left is the first production model
superconducting magnet arriving by truck at
the Laboratory's main gate.
 After
being built and tested, the magnets were installed in the RHIC
tunnel. Because the
particle beam is so small and travels so fast, the magnets had to be
positioned very precisely. The margin of error for installation
was half a millimeter!
 Then,
specialists connected the magnets together, splicing wires and
welding tubes.
 Also
important is the installation of special insulation to wrap every
magnet. Beneath the
silvery insulation layers, super-cold liquid helium bathes the
magnet. This keeps things cold enough for the superconducting wire
to work properly. RHIC
operates at 4.5 degrees above absolute zero on the Kelvin
temperature scale. (That's minus 451.6 degrees Fahrenheit. Absolute zero is
at - 459.67 degrees F, the coldest that anything can be.)
This completes the tour
of the tunnel, now it's on to RHIC's ultimate mission: new
physics.
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