Research
Experimental High-Energy Physics and Astrophysics
The DØ Experiment -- J. Butler, U. Heintz, M. Narain
The DØ Experiment studies proton-antiproton collisions at the world’s highest energy accelerator, the Fermilab Tevatron. In these collisions energy equivalent to almost 2000 times the proton mass is set free. The DØ detector is a large, yet highly sophisticated instrument that measures the fragments of these collisions and allows scientists to study the structure of matter at these high energies.
According to our current understanding, the
basic constituents of matter are quarks and leptons. All the
matter surrounding us is made of the lightest quarks, called
"up" and "down", and the lightest leptons,
the electron and its neutrino. However there exist two additional
families of quarks and leptons with identical properties, except
much larger masses. The heaviest of the quarks, the "top"
quark, was discovered in 1995 by the DØ and CDF collaborations
at Fermilab. The top quark turned out to have an extraordinarily
large mass, approximately the same as an entire gold atom. High-energy
physicists believe that its further study will provide clues to
the origins of mass. Some theorists have speculated that the top
quark may be intimately connected to the electroweak symmetry
breaking mechanism.
Electronics for the DØ Project:
Prof. J. Bulter (left) and undergraduate student
S. Rappoccio with a test stand and the electronic modules
designed and built in
their laboratory for the DØ project at Fermilab.
The members of the Boston University DØ group were
actively involved in the discovery of the top quark and the study
of the carrier of the weak force, the "W boson". The
group is now preparing the detector for the next run in mid 2000,
when the accelerator will start operation with ten times higher
beam intensity. In the resulting collisions thousands of top
quarks will be created, allowing a detailed study of the
properties of this intriguing quark. The Boston University group
has taken leadership roles in the construction of the muon
detection system and the silicon microstrip detectors and will
make significant contributions to the trigger electronics for
these two detection systems.