J. Dyson: Documentation and Diagrams of the Atomic Bomb

Documentation and Diagrams of the Atomic Bomb

File courtesy of Outlaw Labs

Author: J.D. Dyson [jdyson@nyx.net]

DISCLAIMER

The information contained in this file is strictly for academic use alone. UC Berkeley will bear no responsibility for any use otherwise. It would be wise to note that the personnel who design and construct these devices are skilled physicists and are more knowledgeable in these matters than any layperson can ever hope to be... Should a layperson attempt to build a device such as this, chances are s/he would probably kill his/herself not by a nuclear detonation, but rather through radiation exposure. We here at UC Berkeley do not recommend using this file beyond the realm of casual or academic curiosity.

Table of Contents

I. The History of the Atomic Bomb

A. Development (The Manhattan Project)

B. Detonation

1. Hiroshima

2. Nagasaki

3. Byproducts of atomic detonations

4. Blast Zones

II. Nuclear Fission/Nuclear Fusion

A. Fission (A-Bomb) & Fusion (H-Bomb)

B. U-235, U-238 and Plutonium

III. The Mechanism of The Bomb

A. Altimeter

B. Air Pressure Detonator

C. Detonating Head(s)

D. Explosive Charge(s)

E. Neutron Deflector

F. Uranium & Plutonium

G. Lead Shield

H. Fuses

IV. The Diagram of The Bomb

A. The Uranium Bomb

B. The Plutonium Bomb

On August 2nd 1939, just before the beginning of World War II, Albert Einstein wrote to then President Franklin D. Roosevelt. Einstein and several other scientists told Roosevelt of efforts in Nazi Germany to purify U-235 with which might in turn be used to build an atomic bomb. It was shortly thereafter that the United States Government began the serious undertaking known only then as the Manhattan Project. Simply put, the Manhattan Project was committed to expedient research and production that would produce a viable atomic bomb.

The most complicated issue to be addressed was the production of ample amounts of 'enriched' uranium to sustain a chain reaction. At the time, Uranium-235 was very hard to extract. In fact, the ratio of conversion from Uranium ore to Uranium metal is 500:1. An additional drawback is that the 1 part of Uranium that is finally refined from the ore consists of over 99% Uranium-238, which is practically useless for an atomic bomb. To make it even more difficult, U-235 and U-238 are precisely similar in their chemical makeup. This proved to be as much of a challenge as separating a solution of sucrose from a solution of glucose. No ordinary chemical extraction could separate the two isotopes. Only mechanical methods could effectively separate U-235 from U-238. Several scientists at Columbia University managed to solve this dilemma.

A massive enrichment laboratory/plant was constructed at Oak Ridge, Tennessee. H.C. Urey, along with his associates and colleagues at Columbia University, devised a system that worked on the principle of gaseous diffusion. Following this process, Ernest O. Lawrence (inventor of the Cyclotron) at the University of California in Berkeley implemented a process involving magnetic separation of the two isotopes.

Following the first two processes, a gas centrifuge was used to further separate the lighter U-235 from the heavier non-fissionable U-238 by their mass. Once all of these procedures had been completed, all that needed to be done was to put to the test the entire concept behind atomic fission. [For more information on these procedures of refining Uranium, see Section 3.]

Over the course of six years, ranging from 1939 to 1945, more than 2 billion dollars were spent on the Manhattan Project. The formulas for refining Uranium and putting together a working bomb were created and seen to their logical ends by some of the greatest minds of our time. Among these people who unleashed the power of the atomic bomb was J. Robert Oppenheimer.

Oppenheimer was the major force behind the Manhattan Project. He literally ran the show and saw to it that all of the great minds working on this project made their brainstorms work. He oversaw the entire project from its conception to its completion.

Finally the day came when all at Los Alamos would find out whether or not The Gadget (code-named as such during its development) was either going to be the colossal dud of the century or perhaps end the war. It all came down to a fateful morning of midsummer, 1945.

At 5:29:45 (Mountain War Time) on July 16th, 1945, in a white blaze that stretched from the basin of the Jemez Mountains in northern New Mexico to the still-dark skies, The Gadget ushered in the Atomic Age. The light of the explosion then turned orange as the atomic fireball began shooting upwards at 360 feet per second, reddening and pulsing as it cooled. The characteristic mushroom cloud of radioactive vapor materialized at 30,000 feet. Beneath the cloud, all that remained of the soil at the blast site were fragments of jade green radioactive glass. ...All of this caused by the heat of the reaction.

The brilliant light from the detonation pierced the early morning skies with such intensity that residents from a faraway neighboring community would swear that the sun came up twice that day. Even more astonishing is that a blind girl saw the flash 120 miles away.

Upon witnessing the explosion, reactions among the people who created it were mixed. Isidor Rabi felt that the equilibrium in nature had been upset -- as if humankind had become a threat to the world it inhabited. J. Robert Oppenheimer, though ecstatic about the success of the project, quoted a remembered fragment from Bhagavad Gita. «I am become Death,» he said, «the destroyer of worlds.» Ken Bainbridge, the test director, told Oppenheimer, «Now we're all sons of bitches.»

Several participants, shortly after viewing the results, signed petitions against loosing the monster they had created, but their protests fell on deaf ears. As it later turned out, the Jornada del Muerto of New Mexico was not the last site on planet Earth to experience an atomic explosion.

1. Hiroshima

As many know, atomic bombs have been used only twice in warfare. The first and foremost blast site of the atomic bomb is Hiroshima. A Uranium bomb (which weighed in at over 4 & 1/2 tons) nicknamed «Little Boy» was dropped on Hiroshima August 6th, 1945. The Aioi Bridge, one of 81 bridges connecting the seven-branched delta of the Ota River, was the aiming point of the bomb. Ground Zero was set at 1,980 feet. At 0815 hours, the bomb was dropped from the Enola Gay. It missed by only 800 feet. At 0816 hours, in the flash of an instant, 66,000 people were killed and 69,000 people were injured by a 10 kiloton atomic explosion.

The point of total vaporization from the blast measured one half of a mile in diameter. Total destruction ranged at one mile in diameter. Severe blast damage carried as far as two miles in diameter. At two and a half miles, everything flammable in the area burned. The remaining area of the blast zone was riddled with serious blazes that stretched out to the final edge at a little over three miles in diameter. [See diagram below for blast ranges from the atomic blast.]