Tevatron:
the current highest energy collider at Fermi
National Accelerator Lab near Chicago. 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. The machine accelerates protons
and anti-protons up to 99.9999 percent of the speed of light in a
vacuum and brings them into head-on collisions at two points. Amount of
energy released in each of such collisions is 2 TeV (2000 times more than
the proton's mass converted in units of energy via E=mc2)
and gives rise to hundreds of particles spraying away. Two experiments,
called CDF and D0,
were designed and built around the collision points to reconstruct these
fierce events. |
CDF: Collider Detector at
Fermilab, an apparatus comprised of various detectors, electronics,
online and off-line computing built to study the products of colliding
protons and anti-protons. By analyzing these products, we try to reconstruct
what happened in the collision and ultimately figure out how matter is
put together and what forces nature uses to create the world around us.
The CDF Collaboration consists of 525 physicists from 52 institutions representing
11 countries. The CDF detector is about xx m high and xx m long, weighs
about 2,000 tons, and has more than 800,000 individual electronic pathways
for collecting data. |
 Jets:
collimated
sprays of particles. Protons (antiprotons) consist of three quarks (antiquarks)
bound together by the strong force, which unlike any other fundamental
force, is infinitely large at large distances. This force is transmitted
by massless particles called gluons. When proton and antiproton collide,
usually two quarks get kicked out. As they start flying away from the collision
point and in opposite directions, the force between them grows stronger
and results in emission of numerous gluons. In the time scale of 10-23
s, all these gluons and quarks released in collisions pair up to make observable
particles. If the dynamics of the primary scattering of quarks is well
understood, a fair quantitative description of the jet formation process
has been a long standing challenge---the reasons is a bizarre nature of
the strong force that grows infinitely large with distance. |