energy results from thermonuclear (fusion) reactions of the isotopes of hydrogen Have been called
H-bombs or hydragen bombs.

nuclear explosion. Explosive release of energy due to the splitting, or joining, of atfms. The explosion
ig obServaDie by a violent emission of ultraviolet, visible, and infrared (heat) r§diation, gamma
rays, neutrons, and ather particles.
This is accompanied by the formation of a fifleball.
A large
part of the energy from the explosion is emitted as blast and shock waves when det@nated at the
Earth's surface or in the atmosphere. The fireball produces a mushroom-shaped mas@ of not gases and

debris, the top of which rises rapidly.
Fission, fusion, bdiast.

nuclear fusion.

See aiso radiation, gamma rays, fireball, Fpuctear weapon,

See thermonuclear fusion.

nuclear radiation. Particulate and electromagnetic radiation emitted from atomic nucleifiin various
nuctear processes. The important nuclear radiations, from the weapons standpoint, fre alpha and beta
particles, gamma rays, and neutrons. All nuclear radiations are ionizing radiationg, but the reverse
is not true; X-rays, for example, are included among ionizing radiations, but they
@re not nuclear

radiations since they do not originate from atomic nuclei.

nuclear tests.
Tests carried out to supply information required for the design and imprdvement of nuclear
weapons and to study the phenomena and effects associated with nuctear explosions.
nuclide. Any species of atom that exists for a measurable length of time. The term nuclide is used to describe any atomic species distinguished by the composition of its nucleus; ji.e., by Fhe number of pra
tons and the number of neutrons.
I[sotopes of a given element are nuclides having th@ normal number of
protons but different numbers of neutrons in this nuclei. A radionuclide is a radiacdetive nuctide.
NYKOPQ.

New York Operations Office (Atomic Energy Commission).

off-scale. Radiation (or other physical phenomena) greater than the capacity of a measurifhg device to
measure.
ONR.

Office of Naval Research, Washington, D.C.

OPNAY.

Office of the Chief of Navat Operations.

ORNL.

Oak Ridge National Laboratory, Tennessee.

osciltascope.

The name generally applied to a cathode-ray device.

overpressure. The transient pressure, usually expressed in pounds per square inch, exceediffg the ambient
pressure, manifested in the shock (or blast) wave from an explosion.
P2V5 and 6. Twin-engine patro? bomber used for maritime patrol and antisubmarine warfare.
Lockheed for the U.S. Navy. Used in CASTLE as controller and transient ship search.

QDeveloped by

P4¥2,

WLS. Navy.

Four-engine patrol bomber developed by Consolidated from the Air Force B-24 for the

Used in CASTLE as a telemetry receiver for Project 1.4.

PBMSA.

Twin-engine, patrol-bomber flying boat, developed by Martin for the U.S. Navy. Used fin CASTLE for

airlift.

PC.

Patrol craft.

peak overpressure.

The maximum value of the averpressure (which see) at a given location.

permissible contamination or dose. That dose of ionizing radiation that is not expected to
ciable bodily injury to a person at any time during his lifetime.

phantom.

@ause appre-

A volume of material closely approximating the density and effective atomic oumber Pf tissue.

The phantom absorbs jontzing radiation in the same manner as tissue, thus radiation dose§ measurements
made within the phantom provide a means of approximating the radiation dose within a humBn or animal

body under similar exposure conditions.
pressed wood, and beeswax.

Materials commonly used for phantoms are water ,—masonite,

o°9.

A heavily shielded container (usually lead) used to ship or store radioactive materials

2...

Petroleum, afl, and jubricants.

POMaR.

The storage area for these products is referred ta as

Position operational, meteorological aircraft report.

480

POL farm,

Select target paragraph3