\noindent The rapid progress in our understanding of particle physics during 
the last 
fifteen years has brought about the emergence of a picture according to which
matter is made up of two kinds of basic constituents called ``quarks'' and 
``leptons''. The four fundamental forces (strong, electromagnetic, weak and 
gravitational interactions) by which these constituents interact with each 
other, have all been recognized to share several important characteristics.  
Two of these forces, the electromagnetic and weak, are now known to be 
manifestations of a single force (called ``electroweak''), 
and also the strong interaction appears 
to be very similar to the electroweak interaction. 
This progress in understanding was achieved by an intensive mutual
inspiration of theory and experiment, and was only possible due to a 
huge, unprecedented experimental effort in terms of  new accelerators and
very large, ``universal, all-purpose detectors'', designed, built and operated 
by collaborations comprising several hundred physicists from twenty or more 
institutions.

Presently available data agree with the predictions of these theories
(referred to as ``the standard model''), but more experimental effort is needed
to improve the precision of the data, thus subjecting the model to more
stringent tests. Also, of the six quarks assumed in the standard model, only
five have been observed so far and their mass determined. The sixth,
called the ``top'' quark, remains to be seen. Proof of its existence is
one of the important experimental challenges of present research in this
field, and the determination of its mass would provide stringent constraints
on possible extensions of the standard model.
From a theoretical point of view, it would be desirable 
to perform the next step of ``unification'', whereby the electroweak and the
strong interaction become manifestations of one common force; several
candidate theories have  been proposed, which contain the standard model as an 
approximation, and deviations from the standard model are expected to show 
up at higher energies and at higher transverse momenta.

This is why new experiments are being prepared and old experiments are
being upgraded to improve their performance, and why new accelerators
(e.g. the Superconducting Super collider, or SSC) are being planned 
to allow experiments at yet much higher 
energies and higher beam intensities.
At present (and for the foreseeable future), the machine which
     offers the highest energy is the ``Tevatron  collider''  at  FNAL
(Fermi National Accelerator Laboratory near Chicago),
     which allows  the  study  of proton-antiproton collisions at an energy 
of 1.8 TeV, i.e. nearly three times as high as the energy at the CERN collider
where this kind of experiment was pioneered.

   Our group  at  FSU  participates  in one of the two large experiments 
at this collider, named ``D$\emptyset$'' after 
the area in the collider in which it is being installed.
This experiment is being prepared by an international collaboration  of  
groups  from nineteen   universities   and   six National Laboratories.


\bigskip

\noindent {\bf  2.B  Context}
\smallskip

The main components of the D$\emptyset$ detector (as of most  of  the  large  
detectors used in present day particle physics experiments) are a system of 
``drift chambers''
surrounding the interaction region and an array of ``calorimeter'' modules, 
arranged in  such  a way that they cover nearly the full solid angle.  
Drift chambers serve to detect the trajectories of the charged  particles  
created  in  the  collision, while calorimeters are devices which allow 
the measurement of the energies of both charged and  neutral  particles.   

Compared to other collider detectors, the D$\emptyset $ detector is
distinguished by its superior calorimetry based on a liquid argon ionization 
chamber with Uranium
absorber (the largest and most hermetic calorimeter of this kind ever built),
and its excellent muon detection system. Due to these features, this experiment 
is expected to provide a wealth of valuable experimental information which
will serve to further test the standard model mentioned above. Also, there is
good hope that it will prove (or disprove?) the existence of the (so far 
unobserved) top quark.
\smallskip

\noindent {\bf  2.C  Technical Statement}
\smallskip
Together with four of our graduate students, I plan to spend the summer of 
1991 at Fermilab, to work on testing and commissioning of the detector.
This work will include exposing detector modules to a particle beam of known
composition and energy in order to measure the detector response as a function
of particle kind, energy, and position and angle of impact. We will participate
in the preparation and operation of the test setup, as well as in the analysis
of the data taken in these tests. Furthermore, we will work on the 
commissioning of the detector parts that are already installed in the 
experimental area in the collider. This will be done using cosmic rays,
and we will compare the response to the cosmic rays to that expected from
the measurements in the beam.


\noindent {\bf  2.D  Progress}
\smallskip
The preparation of this experiment (planning, design, construction, testing,
calibration,..) has been going on since 1983. Our group joined this project 
in 1985 and has made
substantial contributions to it, in particular to the calorimeter.
I spent five summers at national laboratories, each time together with 
two or more FSU students. During the summer of 1986 at Brookhaven National 
Laboratory (Long Island, NY),
we participated in the construction and testing of two prototype modules.
The summers of 1987 through 1990 were spent at FNAL, where we worked on the 
installation of the 
calorimeter test set-up (1987), the analysis of test measurements 
and further planning for future tests (1988),  testing and debugging of 
calorimeter modules prior to installation in the cryostat of the collider 
experiment, as well as on installation itself (1989), and installation, testing
and calibration (1990).

This year is a critical period in the history of this project, when all the 
detector parts are coming together in the final experimental configuration.
Installation of the detector at the collider has been in progress since 1989
and is expected to be finished by the end of 1991. In parallel,
pre-installation testing as well as commissioning after installation is taking 
place. Members of our group, including four graduate students, are contributing
to the analysis of the test and calibration measurements that were done last 
summer. Preliminary results indicate that the detector performs according to
expectations, but substantial work remains to be done to make sure that 
the complete detector system is ready, and that we
understand its perfomance as well as possible before the actual data taking
at the collider in 1992.
I hope that members of the FSU group will continue the tradition of 
making valuable contributions to this huge effort.
We expect that the test and calibration measurements will lead to two 
technical publications, and we are looking forward to the first physics results
in 1992.