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Re: Dangerous Ion Colliding Experiment?



Hi all,
I wanted to present some answers that been raised since my
message on Saturday night. First, for William Beaty, "today" means
October 1, 1999 (or day 1 for the DOE's fiscial year 2000 - then the
money comes through for running the machine for the year). However,
there is currently an engineering run underway, where the accelerator
physicists are seeing if they can cool down the rings (magnets contain
superconducting magnets) and make particles fly around. Just last week,
they got beam to circulate many times in one of the rings (capture the
RF cavities). The other ring is still being cooled because of problems
in its refridgerator unit. So as you can tell, this is mostly
"debugging".
Second, there is an equation for the energy density of the
collision region that was first given in J.D. Bjorken's 1983 paper in
Phys. Rev. D. I cannot currently locate my copy since I am vacating my
University office and getting ready for high school (which begins on
Aug. 9 here). However, it is an excellent paper that can maybe answer
some questions.
Finally, for Jack, you are correct that there is a "quark-gluon"
party line which depends on some quantities that vary depending on the
model used. That is the hard part with high energy nuclear physics,
there are so many unknowns about the nuclear effects and the magntiude
of the role they play in the collisions. It may never happen or there
may be a smooth transition or .... The list goes on and on. (Who gave
the colliqium? That might shed some light on the subject) The CERN
experiments have produced some results that push the realms of our
understanding. We currently do not models of normal hadronic matter to
explain the J/Psi suppression seen by NA50 (my research topic).
However, we don't know enough about the partonic aspect to apply it.
Using either a string model or a partonic cascade is the current work.
There are other results which point to a QGP (quark-gluon plasma)
production but hint of bad data analysis. The other result I have not
heard discussed in this manner (as much as the others) is the increased
strangeness production. This alone cannot prove a QGP. There is much
work to do.
Also, I agree with Kolb's statement. We are not trying to
recreate the early universe. That is impossible. Supposedly, it is the
same state as the matter then but the conditions are no way close to the
early universe (if you believe in the big bang). So many loopholes and
theories and models. I am not comfortable with the analogy for this
very reason, but what I am sure of is. We are exploring matter at
energies and densities never before seen in a terrestial lab and that is
exactly what we are doing.


Sam Held