Number 151, November 15, 1993 by Phillip F. Schewe and Ben Stein
JOHN PEOPLES WILL OVERSEE THE DISMEMBERMENT OF THE SSC while retaining
his directorship at Fermilab. Peoples replaces Roy Schwitters, who resigned
last week as head of the SSC. An estimated $1.5 billion in SSC shutdown
money will go largely for severance to displaced SSC employees and for
settling claims from SSC contractors. (The New York Times, 9 Nov. 1993.)
DISPOSSESSED AMERICAN PARTICLE PHYSICISTS are looking around for alternative
research venues. British science minister William Waldegrave has suggested
informally that "CERN should immediately invite the US in as a member
state." Other countries such as Italy and France are not keen on this
idea, not wanting the US (or Japan) to gain an undue influence over what
until now has been a European venture. Stanford scientist Sidney Drell
favors the creation of a whole new, truly worldwide, Center for International
Nuclear Research (CIRN). Short term plans must also be pursued. Tom Kirk,
who left Fermilab for the SSC, says that some of the scientists who worked
with him on the Solenoidal Detector Collaboration (SDC) at SSC may be able
to apply the fruits of their efforts (knowledge if not hardware) in some
way to the development of detectors at the proposed Large Hadron Collider
at CERN. (Physics World, Nov. 1993.)
A SELF-FOCUSING LASER has been developed at AT&T Bell Labs. The
layered semiconductor device is patterned on top with a set of micron-sized
concentric grooves, which constitute a sort of Fresnel lens. Infrared laser
light, emitted from this top face, is focused to an 8- micron spot size.
Daryoosh Vakhshoori of Bell Labs believes this "zone laser" will
promote a better coupling of laser light into external optical fibers.
(Science News, 6 Nov. 1993.)
SOLAR RADIATION VARIES only a few tenths of a percent at visible wavelengths
over the sun's activity cycle, but varies by as much as a factor of 10
at extreme-ultraviolet and x-ray wavelengths. Solar UV radiation has an
important role in Earth's atmospheric chemistry, particularly in the formation
of stratospheric ozone. UV rays help to make ozone (from atmospheric oxygen)
in the first place; then the ozone protects living organisms from harmful
effects of the UV. The sun's UV flux, monitored by the Upper Atmospheric
Research Satellite (UARS), is declining now as the sun passes into the
less-active part of its 11-year cycle. By studying the solar UV spectrum
over short and long periods of time, UARS hopes to provide information
that can lead to a differentiation between natural and anthropogenic sources
of ozone variability. (Physics World, Oct. 1993.)
MOLECULAR DYNAMICS (MD) SIMULATIONS have gotten faster. These computer
studies track the behavior of a hypothetical ensemble of particles subject
to a specific law of motion incorporating the complex interactions among
neighboring particles. As part of a study of supersonic projectiles, scientists
at Los Alamos have simulated the 3-dimensional movement of 180 million
particles, with 4 updated configurations per microsecond. Less than a year
ago, the largest comparable MD simulation tracked 17 million particles.
The Los Alamos computer system had a sustained speed of 50 Gigaflops. (Physics
World, Oct. 1993.)
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