cancers and to some endocrine disorders.

_Nuclear Chemistry_

For techniques of radiochemistry to be employed successfully, high
interaction rates (and therefore high beam intensities) are needed. For
this reason, chemistry targets are usually inserted right into the
cyclotron so that they can be bombarded directly by the circulating
beam. After the bombardment is completed the target is removed from the
cyclotron. It is then taken to a chemistry laboratory and subjected to
detailed chemical procedures. Individual elements are removed, and the
radioactive isotopes of each element are identified by quantitative
counting techniques. In some cases a mass spectrometer is used to
analyze the products. Many deductions about the nature of the breakup of
the target nucleus can be drawn from the pattern of the observed
radioactive products. Sometimes the nucleus splits almost in half. This
is called fission. More frequently smaller parts of the nucleus are
split off. Two general types of reactions, known as spallation and
fragmentation, are distinguished. One of the goals of this research is
to learn more about the constitution of the nucleus and of the forces
which bind the particles in the interior of the nucleus.

FOOTNOTES:

[7] Mesons are elementary particles intermediate in mass between the
electron and proton.

[8] It may be interesting to note that the [pi]^0 meson was discovered
with this cyclotron in 1950. This was the first particle to be
discovered with an accelerator. All particles that had been previously
discovered were observed first in cosmic rays or some other form of
natural radiation.

BIBLIOGRAPHY

1. Gerald A. Behman, Particle Accelerators: I. Bibliography, II. List
of Accelerator Installations, UCRL-8050, January 1, 1958.

2. Samuel Glasstone, The Acceleration of Charged Particles, in
_Sourcebook on Atomic Energy_, Second Edition (Van Nostrand,
Princeton, 1958), Ch. IX.

3. M. S. Livingston, _High-Energy Accelerators_ (Interscience
Publishers, New York, 1954).

4. M. Stanley Livingston and Edwin M. McMillan, History of the
Cyclotron, Physics Today _12_, 18-34 (October 1959).

5. E. M. McMillan, Particle Accelerators, in _Experimental Nuclear
Physics_, Emilio Segre, Editor, Vol. III (Wiley, New York, 1959),
Part XIII.

6. Bob H. Smith _et al._, The Electrical Aspects of the UCRL 740-Mev
Synchrocyclotron, UCRL-3779 Rev., October 2, 1957.

7. Robert L. Tho