Number 208, December 22, 1994 by Phillip F. Schewe and Ben Stein
THE CERN COUNCIL HAS APPROVED THE CONSTRUCTION OF THE LARGE HADRON COLLIDER
(LHC). The huge proton-proton collider, to be housed in the existing 27-
km tunnel used by the Large Electron Positron collider, will be built in
two stages. First, 5-TeV beams will be achieved by about the year 2004.
Head-on collisions would have a total energy of 10 TeV. Primary topics
of study in this first phase would be top quarks and CP violation. In the
second phase, to start in 2008, the total collision energy would be boosted
to 14 TeV. At this energy the search for the Higgs boson would be a high
priority. Financial investments by non- member states such as the U.S.,
Russia, and Japan, would influence the rate at which construction would
proceed.
ELEMENT 111 HAS BEEN DISCOVERED at the same German lab, the Gesellschaft
fur Schwerionenforschung (or GSI for short) in Darmstadt, where a few weeks
ago the discovery of Element 110 was announced. Element 111 has an atomic
weight of 272 and was created by shooting a nickel beam at a bismuth target.
Only a few of the new atoms were detected, and they quickly decayed after
the original collision. One of the daughter particles, an atom of Element
109 with an atomic weight of 268, and one of the further decay products,
an atom of Element 107 with an atomic weight of 264, were themselves isotopes
that had never been observed before. (New York Times, 22 December 1994.)
SOME OF THE EQUATIONS RELATED TO SUPERSYMMETRY THEORY have been solved
exactly by Edward Witten of the Institute for Advanced Study at Princeton
and his colleague Nathan Seiberg of Rutgers. Supersymmetry theory seeks
to incorporate all four known physical forces including gravity into a
single mathematical framework. It does this by presuming a special relation
between fermions (particles such as quarks with half-integral spin) and
bosons (particles such as photons with an integer-valued spin). Although
Witten's achievement addresses the subject of quark confinement---why the
strong force operating between quarks actually increases as the quarks
move apart---the chief beneficiaries of the new results will be mathematicians
who work with multidimensional geometry. Harvard mathematician Clifford
Taubes has said that Witten's work will speed up calculations and shorten
proofs. (Science, 9 December 1994.)
NON-NEUTRAL PLASMAS are less well studied than plasmas in which positively-charged
ions and electrons intermingle. However, recent work on storing non-neutral
plasmas in atom traps has shown that fairly high numbers---up to a billion
same-charge particles---and lengthy storage periods---hours and days---can
now be achieved. Non-neutral plasmas are of interest partly because in
some cases they can remain intact longer than neutral plasmas and partly
because they constitute an ideal fluid for studying turbulence. At last
month's meeting of the APS plasma physics division in Minneapolis, Fred
Driscoll of the University of California at San Diego reported that in
a turbulent spheroidal-shaped electron plasma (electrons confined in a
trap) a number of long-lived vortices formed themselves into a regular
array. Eventually these vortices disappeared. Another San Diego researcher,
Cliff Surko, said that he was storing positrons (up to 100 million) in
his trap as a way of studying the sort of matter-antimatter interactions
that occur at the heart of the Milky Way galaxy. (Science, 9 December 1994.)
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