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[Written by individuals at the American Institute of Physics and
merely posted by me, so respond to <pfs2@aip.org> or other
references below.  Always posted here on sci.research; usually
crossposted to an eclectic and hopefully appropriate selection of 
other newsgroups, with followups directed here. Back issues may be 
ftp'd from NIC.HEP.NET, along with FYI and the American Physical 
Society news/opinion column WHAT'S NEW.  Astro folks should note
that the new moderated group sci.astro.research will receive all
PNUP's, or at least the astro-relevant ones, directly from AIP.
Enjoy! -jc]

PHYSICS NEWS UPDATE
A digest of physics news items by Phillip F. Schewe, American
Institute of Physics                      physnews@aip.org
Number 184  June 21, 1994

THE MOST PRECISE MEASUREMENT YET OF THE
WEINBERG ANGLE has been made by physicists at the Stanford
Linear Collider (SLC). The Weinberg angle (or, in practice, the
square of the sine of the angle) is a parameter that describes the
mixing between the weak force (carried by Z bosons) and the
electromagnetic force (carried by photons).  It is therefore of
fundamental importance in the study of the standard model of
elementary particles.  The SLC scientists actually observed the
asymmetry in the decay of Z bosons created when micron-sized
beams of positrons and polarized electrons (electrons whose spins
have been oriented in a special way) collided head on.  With a sample
of more than 50,000 Z's, the SLC researchers have determined an
effective value of 0.2294 (with an uncertainty of 0.0010) for the
Weinberg parameter, which differs by a fair amount (2.3 standard
deviations) from the average value, 0.2321, derived from a composite
of many measurements made at the LEP collider in Geneva.  (K. Abe
et al., Physical Review Letters, 4 July 1994.)

INTERFEROMETRY OF IODINE MOLECULES has been carried
out by physicists at the University of Paris-North in France (Physics
Letters A, vol. 188, p 187).  Exploiting the wavelike properties of
matter, scientists have over the years been able to split photons,
neutrons, electrons, and, more recently, whole atoms into separate
wave trains which are later caused to interfere with each other,
resulting in a characteristic pattern of fringes. Extending this principle
to iodine molecules, the French researchers use laser beams to split
and then to recombine the molecule waves.  (New Scientist, 4 June
1994.)

MYOGLOBIN MYSTERIES MADE MANIFEST. Myoglobin is a
red protein that stores oxygen molecules in muscle tissue.  To learn
more about how myoglobin works, researchers study how the protein
binds to the experimentally more convenient molecule carbon
monoxide (CO).  In what may be one of science's coolest movies,
Joel Berendzen of Los Alamos (505-665-2552) and his colleagues at
the Max Planck Institute in Heidelberg, Rice University, and
Brookhaven have produced the first-ever sequence showing the
intrepid protein before, while, and after it reacts with CO.  The
researchers combined very low temperatures (to slow things down)
with x-ray diffraction techniques to obtain pictures of the CO-protein
pair at atomic (1.5 Angstroms) resolution. These pictures reveal that
the iron atom in myoglobin moves out of the plane of the heme (the
"business end" of the protein where the reaction takes place) and that
bonds more distant from the CO molecule assume a high-energy state
when the CO gets zapped off.  (Paper at upcoming meeting of the
American Crystallographic Association in Atlanta, June 27-July 1.)

TWO PHYSICS JOURNALS WILL BE AVAILABLE ONLINE via
Internet in 1995.  Applied Physics Letters (APL), published by the
American Institute of Physics, plans to start its online service in
January 1995.  Physical Review Letters (PRL), published by The
American Physical Society, should be available by mid year.  Users
of the online version of APL will be able to make "hypertext" jumps.
That is, a reader can position her cursor at a particular item in the
references, say, and with a single click can call up additional
information (such as an abstract) concerning that article.  Also, a
year's worth of back issues will be available on CD-ROM.  (Physics
Today, June 1994.)