Pictures were obtained showing conf! wiateen
four pri. aries and two secondaries.
project report.
of acthee nm .terials on
Further details will be
«ain the
Program 13, Reaction History
Program 13 measured alpha as a function of time for the fission devices and primaries tn order to determine whether they worked properly,
and in case they did not, to aide {n diagnosing the trouble. It also made
measurements indicating the “transit time" for the HE implosion and time
from load ring pulse to very early gamma levels in the device,
Alpha detectors, each consisting of a plastic fluor and photocell or
photomultiplier combination in a lght-tight can, were mounted at appropriate
distances from the devices to give a wide range in sensitivity. The signals
were conducted over coaxial cables, which were shielded against gamma,
neutron, and electromagnetic radiation, to concrete bunkers. These signals
then were displayed on a series of high speed oscilloscopes together with:
timing frequencies and were recorded by cameras. Similar detectors, very
near the device, gave signals which were telemetered by a wide band ultra
high frequency transmitter~receiver combination and recorded on oscilloscopes. |
For details on results of the alpha measurements the reader is referred
to the project reports.
°
Program 14, Phonex-Pinex
The objective of Program 14 was to obtain neutron spectra at a number
allowed to form an image of the source on a hydrogen-containing thin plastic
foil by means of a pinhole placed in a mile-long vacuum pipe. Recoil protons from this foil passed through a collimating system and were recorded
on nuclear emulsion plates. Tracks were counted and measured to determine
the spectrum of the incident neutrons.
Program 15, Photo-Physics
Program 15 was conducted to obtain radius versus time data for
hydrodynamic yield determinations, to determine the nature and behavior of
a nuclear detonation by photographing the light produced during the initial
stages of the detonation, and to study the reaction rate in the secondary of
a two-stage device of megaton yield by means of gammas and neutrons
emitted from the secondary at various positions.
_
Framing cameras were operated from several photo stations on each
shot to record the growth of the fireball. Very high speed streak cameras
were used to record the history of the light arising near the bomb in the
first few microseconds. A pinhole in a mile-long vacuum pipe was used to
collimate gamma rays and neutrons onto a plastic fluor. Light from the
fluor was photographed with high speed streak cameras to record the gamma
versus time history and the arrival rate of the neutrons. The latter makes
possible the determination of the neutron spectrum at various places.
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