Anatomy of Accelerators

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Anatomy of Accelerators

• Marty Peters
• Summer 2006

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Linear Accelerators
The 3 km long linear accelerator at
Stanford.Photo Stanford Linear Accelerator
Center
Source http//nobelprize.org/physics
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Fermi National Accelerator Laboratory

• Fermilab is home to the Tevatron, the world's
  highest-energy particle accelerator.Four miles
  in circumference, the Tevatron is housed in a
  tunnel about 30 feet below the big ring you see
  in this aerial view of the laboratory. A series
  of accelerators is used to send particles racing
  around the Tevatron at 99.9999 percent of the
  speed of light in a vacuum. The particles
  complete the four-mile course nearly 50 thousand
  times a second.

Source www.fnal.gov
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Two kinds of particles, protons and antiprotons,
are sent around the ring in opposite directions.
At two points in the ring, streams of these
particles (called "beams") are steered right into
each other, and collisions, at the rate of almost
two million each second, are watched.
Computer view of proton-antiproton collision.
Source www.fnal.gov, http//quarknet.fnal.gov
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Antiproton Production

• To make antiprotons, protons are accelerated to
  120 billion electron-volts (120 GeV) and strike
  them against a solid target. Out of the target
  come both antiprotons and secondary protons.
  There are about five secondary protons to each
  antiproton.
• The system gets about 50 million antiprotons per
  shot off the target.

Source www.highbeam.com
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Antiprotons were produced by operating the Main
Ring at 120 GeV. The antiprotons were collected
in a Debuncher ring before they were transferred
to the Accumulator where stochastic cooling was
applied. After cooling, the antiprotons were
injected into the Main Ring and Tevatron for
acceleration to 1 TeV. With the recent extension
of the Fermilab complex, the main Ring has been
replaced by a new rapid cycling 120 GeV
synchrotron, the Main Injector. In the same
tunnel, an 8 GeV storage ring, the Recycler, has
been constructed using permanent magnets. The
Recycler acts as a repository for cooled
antiprotons, thus permitting a high rate of
cooling in the Accumulator which works best with
low currents, to be maintained. The Recycler also
receives antiprotons left over and decelerated
after completion of a storage in the Tevatron.
Stochastic cooling, initially installed in the
Recycler, will be enhanced by the addition of
electron cooling in the near future. Source
/nobelprize.org/physics
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In a single head-on collision between proton and
antiproton in the Tevatron, hundreds of new
particles are usually created. According to
Einsteins formula Emc2, the maximum mass that
can be converted from kinetic energy corresponds
to the mass of about 2000 protons, if all the
kinetic energy of the proton and antiproton in a
single collision were to be converted to mass.
Source /nobelprize.org/physics
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DZero Collider Detector

• Fermilab's two collider detectors--CDF and
  DZero--are about four stories high and weigh some
  5,000 tons (10 million pounds) each. The particle
  collisions occur in the center of the detectors,
  which are crammed with electronic instrumentation.

Source www.fnal.gov
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Source http//quarknet.fnal.gov
Source http//quarknet.fnal.gov
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Source http//quarknet.fnal.gov
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CDF Collider Detector

• Each detector has about one million individual
  pathways for recording electronic data generated
  by the particle collisions. The signals are
  carried over nearly a thousand miles of wires and
  cables--each one connected by hand and tested
  individually.

Source www.fnal.gov
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Schematic of Modern Detector
Source particleadventure.org
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Interaction of Particles with Detector Components
Source particleadventure.org