Number 119, March 19, 1993 by Phillip F. Schewe and Ben Stein
ELECTRONIC-MAIL CIRCULATION OF PHYSICS ARTICLES has increased greatly
in the last few years owing to the ubiquity of personal computers and the
advent of flexible software for transmitting text files. One set of electronic
bulletin boards, established by Paul Ginsbarg at Los Alamos, receives 600
theoretical-physics preprints monthly. The more than 8000 subscribers can
choose abstracts from a menu and can even receive whole-article texts.
Many physicists, particularly those abroad with scant access to certain
printed journals, claim that bulletin boards like this are now their principal
way of getting timely reports of new research. Critics say that the lack
of peer review and a growing tendency (encouraged by an easily available
communications channel) to rush into print may result in a lowering of
publishing standards. The established print journals are not overlooking
the power of electronic transmission. The European journals Nuclear Physics
A and B will soon make available in electronic form articles that have
been accepted for publication but not yet published. The American Physical
Society is also considering online publishing. (Science, 26 Feb. 1993.)
THE ADVANCED NEUTRON SOURCE (ANS) , a high-flux reactor to be built at
Oak Ridge, will provide 10-20 times more neutrons than the Institut Laue
Langevin (ILL) in Grenoble, France, currently the best source of research
neutrons from a reactor. Such neutrons are used in studying the structure
of materials. The $1.5 billion ANS should arrive with the millennium. Meanwhile
at the Rutherford Appleton Lab in the UK, the ISIS neutron source reached
its design current last month. ISIS is the world's leading spallation neutron
source; 800-MeV protons are smashed into a target, producing a rich beam
of neutrons, as well as neutrinos, which can be used for experiments, such
as in the German KARMEN neutrino detector. A muon beam may also be set
up. (Physics World, March 1993.)
THE BERRY PHASE , a phase shift acquired by quantum systems solely from
topological effects, can create noticeable effects in even simple chemical
reactions. Chemists once thought that reaction rates for simple exchange
reactions such as H+H2H2+H could be determined from first principles. Mark
Wu and Aron Kupperman of Caltech have found that theoretical calculations
for the D+H2DH+H reaction fit experimental data better when they included
this esoteric phase effect, named after the University of Bristol's Michael
Berry, who discovered it in quantum systems in 1983. (Physics Today, March
1993.)
A 2.7-M LIQUID TELESCOPE MIRROR has been fashioned by spinning a bowl
of mercury about a vertical axis. The rotating mercury assumes a parabolic
shape and reflects 80% of the incident light. The telescope is cheap (costing
less than $200,000) but not steerable; in a perpetually upright orientation,
its field of view is an overhead strip only 1/3 of a degree wide. Nevertheless,
scientists at the University of British Columbia hope to find 100,000 galaxies
(as faint as magnitude 21) and 2000 quasars. (Sky & Telescope, April
1993.)
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