Evening star., 1949-01-31
Stars, Men and Atoms
Another Elemental Particle
Of Matter Believed Found
Light Meson', 80 Times Heavier
Than Electron, Has No Charge
By Thomas r. Henry


Probable discovery of new elemental par.
ticle OF matter, hitherto unknown building
stone OF the universe, has just been reported
1t is the light meson," q particle without
any electrical charge, which weighs about 30
times as much as an electron. It's existence Is
postulated by DR.. E. w. Cowan OF the Cali.
fornia Institute of Technology from one photo
graph taken at an altitude of about six miles.
This photograph shows an apparent collision
In the upper atmosphere between an electron,
the negatively charged elementary particle
which is essentially weightless, and something
which undoubtedly has weight but which does
not mt into any previously known picture
The meson today is one of the great mys-
teries Of science and much of the future of
atomic research requires clearer understand.
Ing OF it. Generally, it has been pictured as
particle about 200 times the mass of an elec-
tron which somehow arises in the disintegra.
tion OF an atomic nucleus, and has a free life
time of only about billionth of a second. Re-
cent British research has stressed the likelihood
OF two kinds of mesons, one of about half the
weight OF the other, but the type of particle
postuated by DR.. Cowan has not hitherto been
reported.
Nelson's appear only in cosmic ray studies.
They appear with the smashing of atoms by
these ultra powerful particles from outer space
with which the earths outer atmosphere con-
stantly is bombarded
When a collision takes place between two
elementary particles, themselves infinitely be.
low the limit of visibility, the tracks which
they make through cloud chamber of knock
ing outer eIectrons from atoms along their
path can be photographed. The angle between
the paths of the colding particles gives an
indication of their masses
Both particles after the collision, Dr. Cowan
found, moved with about half the speed of
light and apparently acted like ideal elastic
balls.
If his Interpretation of the photograph is
accepted, the list of elementary particles of
matter will stand at seven to date-electron.
proton neutron, positron with the same mass
as an electron but with a positive electrical
charge, and three kinds of mesons There is
also the neutrino, particle of about the
weight of an eiectron with no electrical charge.
which never has been discovered but whose
existence is postulated.
Individual red blood cells have been made
to take their own photographs.
This achievement has been reported to the
American Association for the Advancement of
Science by DR.. George A. Boyd and his associ-
ates of the University of Rochester
The majority of these cells are manufac-
tured in the bones marrow. They are extremely
complex structures in which are incorporated
number of proteins the nitrogen-contain-
ing building stones of the body.
During the course of their manufacture, 1t
was found some of these proteins have tend
ency to incorporate Carbon IA, the most com.
mon radioactive form of the element which
is the cornerstone Of all life. When one Of
these atoms later explodes, its radiation pro-
duces an image on Photographic plate
In the technique used by DR.. Boyd and his
associates minute amounts Of radiocarbon were
fed to rat and at different periods there
after blood was taken from its tail. This blood
was smeared on special Photographic plates
which then were left in the dark for 81 days.
When these plates were developed, there were
clearly defined pictures. They showed the shape
and somewhat of the structure of the red blood
cells. Several types of cells were photographed.
This may give some clue to the rate of forma-
ton in the bone marrow and their probable
length of life. The rarest pictures presumably
were of the cells with the shortest life spans.
The technique used by DR.. Boyd is known as
autoradography and hitherto has been used
in the study of such matters as the rate Of blood
flow through various parts of the body Making
individual cells take their own pictures, how.
ever, is great extension of anything accom-
plished before. The value of the technique in
diagnosis remains to be developed in the future.
One drawback for general use is that radiocar-
bon is rather dangerous substance. 1t cannot
be used freely with human beings because of
its long life and the slowness with which it is
eliminated