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Plutonium Bomb
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_________________/______\_________________
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[2]-------> | : ||: : |
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| : ||: : |
| :______||:_____________________________: |
|/_______||/______________________________\|
\ ~\ | : |:| /
\ |\ | : |:| /
\ | \ | :__________|:| /
\ |:_\ | :__________\:| /
\ |___\ |______________| /
\ | \ |~ \ /
\|_______\|_________________\_/
|_____________________________|
/ \
/ \
/ \
/ _______________ \
/ ___/ \___ \
/____ __/ \__ ____\
[3]_______________________________ \ ___|
/ __/ \ \__ \
/ / \/ \ \
/ / ___________ \ \
/ / __/___________\__ \ \
./ /__ ___ /=================\ ___ __\ \.
[4]-------> ___||___|====|[[[[[|||||||]]]]]|====|___||___ <------[4]
/ / |=o=o=o=o=o=o=o=o=| <-------------------[5]
.' / \_______ _______/ \ `.
: |___ |*| ___| :
.' | \_________________ |*| _________________/ | `.
: | ___________ ___ \ |*| / ___ ___________ | :
: |__/ \ / \_\\*//_/ \ / \__| :
: |______________:|:____:: **::****:|:********\ <---------[6]
.' /:|||||||||||||'`|;..:::::::::::..;|'`|||||||*|||||:\ `.
[7]----------> ||||||' .:::;~|~~~___~~~|~;:::. `|||||*|| <-------[7]
: |:|||||||||' .::'\ ..:::::::::::.. /`::. `|||*|||||:| :
: |:|||||||' .::' .:::''~~ ~~``:::. `::. `|\***\|:| :
: |:|||||' .::\ .::''\ | [9] | /``::: /::. `|||*|:| :
[8]------------>::' .::' \|_________|/ `::: `::. `|* <-----[6]
`. \:||' .::' ::'\ [9] . . . [9] /::: `::. *|:/ .'
: \:' :::'.::' \ . . / `::.`::: *:/ :
: | .::'.::'____\ [10] . [10] /____`::.`::.*| :
: | :::~::: | . . . | :::~:::*| :
: | ::: :: [9] | . . ..:.. . . | [9] :: :::*| :
: \ ::: :: | . :\_____________________________[11]
`. \`:: ::: ____| . . . |____ ::: ::'/ .'
: \:;~`::. / . [10] [10] . \ .::'~::/ :
`. \:. `::. / . . . \ .::' .:/ .'
: \:. `:::/ [9] _________ [9] \:::' .:/ :
`. \::. `:::. /| |\ .:::' .::/ .'
: ~~\:/ `:::./ | [9] | \.:::' \:/~~ :
`:=========\::. `::::... ...::::' .::/=========:'
`: ~\::./ ```:::::::::''' \.::/~ :'
`. ~~~~~~\| ~~~ |/~~~~~~ .'
- Diagram Outline -
---------------------
[1] - Tail Cone
[2] - Stabilizing Tail Fins
[3] - Air Pressure Detonator
[4] - Air Inlet Tube(s)
[5] - Altimeter/Pressure Sensors
[6] - Electronic Conduits & Fusing Circuits
[7] - Lead Shield Container
[8] - Neutron Deflector (U-238)
[9] - Conventional Explosive Charge(s)
[10] - Plutonium (Pu-239)
[11] - Receptacle for Beryllium/Polonium mixture
to facilitate atomic detonation reaction.
[12] - Fuses (inserted to arm bomb)
Uranium Bomb
/\
/ \ <---------------------------[1]
/ \
_________________/______\_________________
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[2]-------> | : ||: : |
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| : ||: : |
| : ||: : |
| : ||: : |
| :______||:_____________________________: |
|/_______||/______________________________\|
\ ~\ | | /
\ |\ | | /
\ | \ | | /
\ | \ | | /
\ |___\ |______________| /
\ | \ |~ \ /
\|_______\|_________________\_/
|_____________________________|
/ \
/ _________________ \
/ _/ \_ \
/ __/ \__ \
/ / \ \
/__ _/ \_ __\
[3]_______________________________ \ _|
/ / \ \ \
/ / \/ \ \
/ / ___________ \ \
| / __/___________\__ \ |
| |_ ___ /=================\ ___ _| |
[4]---------> _||___|====|[[[[[[[|||]]]]]]]|====|___||_ <--------[4]
| | |-----------------| | |
| | |o=o=o=o=o=o=o=o=o| <-------------------[5]
| | \_______________/ | |
| |__ |: :| __| |
| | \______________ |: :| ______________/ | |
| | ________________\|: :|/________________ | |
| |/ |::::|: :|::::| \| |
[6]----------------------> |::::|: :|::::| <---------------------[6]
| | |::::|: :|::::| | |
| | |::==|: :|== <------------------------[9]
| | |::__\: :/__::| | |
| | |:: ~: :~ ::| | |
[7]----------------------------> \_/ ::| | |
| |~\________/~\|:: ~ ::|/~\________/~| |
| | ||:: <-------------------------[8]
| |_/~~~~~~~~\_/|::_ _ _ _ _::|\_/~~~~~~~~\_| |
[9]-------------------------->_=_=_=_=_::| | |
| | :::._______.::: | |
| | .:::| |:::.. | |
| | ..:::::'| |`:::::.. | |
[6]---------------->.::::::' || || `::::::.<---------------[6]
| | .::::::' | || || | `::::::. | |
/| | .::::::' | || || | `::::::. | |
| | | .:::::' | || <-----------------------------[10]
| | |.:::::' | || || | `:::::.| |
| | ||::::' | |`. .'| | `::::|| |
[11]___________________________ ``~'' __________________________[11]
: | | \:: \ / ::/ | |
| | | \:_________|_|\/__ __\/|_|_________:/ | |
/ | | | __________~___:___~__________ | | |
|| | | | | |:::::::| | | | |
[12] /|: | | | | |:::::::| | | | |
|~~~~~ / |: | | | | |:::::::| | | | |
|----> / /|: | | | | |:::::::| <-----------------[10]
| / / |: | | | | |:::::::| | | | |
| / |: | | | | |::::<-----------------------------[13]
| / /|: | | | | |:::::::| | | | |
| / / |: | | | | `:::::::' | | | |
| _/ / /:~: | | | `: ``~'' :' | | |
| | / / ~.. | | |: `: :' :| | |
|->| / / : | | ::: `. .' <----------------[11]
| |/ / ^ ~\| \ ::::. `. .' .:::: / |
| ~ /|\ | \_::::::. `. .' .::::::_/ |
|_______| | \::::::. `. .' .:::<-----------------[6]
|_________\:::::.. `~.....~' ..:::::/_________|
| \::::::::.......::::::::/ |
| ~~~~~~~~~~~~~~~~~~~~~~~ |
`. .'
`. .'
`. .'
`:. .:'
`::. .::'
`::.. ..::'
`:::.. ..:::'
`::::::... ..::::::'
[14]------------------> `:____:::::::::::____:' <-----------------[14]
```::::_____::::'''
~~~~~
- Diagram Outline -
---------------------
[1] - Tail Cone
[2] - Stabilizing Tail Fins
[3] - Air Pressure Detonator
[4] - Air Inlet Tube(s)
[5] - Altimeter/Pressure Sensors
[6] - Lead Shield Container
[7] - Detonating Head
[8] - Conventional Explosive Charge
[9] - Packing
[10] - Uranium (U-235) [Plutonium (See other diagram)]
[11] - Neutron Deflector (U-238)
[12] - Telemetry Monitoring Probes
[13] - Receptacle for U-235 upon detonation
to facilitate supercritical mass.
[14] - Fuses (inserted to arm bomb)
Atomic Fission
There are 2 types of atomic explosions that can be facilitated by
U-235; fission and fusion. Fission, simply put, is a nuclear reaction in
which an atomic nucleus splits into fragments, usually two fragments
of comparable mass, with the evolution of approximately 100 million to
several hundred million volts of energy. This energy is expelled
explosively and violently in the atomic bomb. A fusion reaction is
invariably started with a fission reaction, but unlike the fission
reaction, the fusion (Hydrogen) bomb derives its power from the fusing
of nuclei of various hydrogen isotopes in the formation of helium
nuclei. Being that the bomb in this file is strictly atomic, the other
aspects of the Hydrogen Bomb will be set aside for now.
The massive power behind the reaction in an atomic bomb arises from
the forces that hold the atom together. These forces are akin to, but
not quite the same as, magnetism.
Atoms are comprised of three sub-atomic particles. Protons and
neutrons cluster together to form the nucleus (central mass) of the
atom while the electrons orbit the nucleus much like planets around a
sun. It is these particles that determine the stability of the atom.
Most natural elements have very stable atoms which are impossible to
split except by bombardment by particle accelerators. For all practical
purposes, the one true element whose atoms can be split
comparatively easily is the metal Uranium. Uranium's atoms are
unusually large, henceforth, it is hard for them to hold together firmly.
This makes Uranium-235 an exceptional candidate for nuclear fission.
Diagram of a Chain Reaction
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|
[1]------------------------------> o
. o o .
. o_0_o . <-----------------------[2]
. o 0 o .
. o o .
|
\|/
~
. o o. .o o .
[3]-----------------------> . o_0_o"o_0_o .
. o 0 o~o 0 o .
. o o.".o o .
|
/ | \
|/_ | _\|
~~ | ~~
|
o o | o o
[4]-----------------> o_0_o | o_0_o <---------------[5]
o~0~o | o~0~o
o o ) | ( o o
/ o \
/ [1] \
/ \
/ \
/ \
o [1] [1] o
. o o . . o o . . o o .
. o_0_o . . o_0_o . . o_0_o .
. o 0 o . <-[2]-> . o 0 o . <-[2]-> . o 0 o .
. o o . . o o . . o o .
/ | \
|/_ \|/ _\|
~~ ~ ~~
. o o. .o o . . o o. .o o . . o o. .o o .
. o_0_o"o_0_o . . o_0_o"o_0_o . . o_0_o"o_0_o .
. o 0 o~o 0 o . <--[3]--> . o 0 o~o 0 o . <--[3]--> . o 0 o~o 0 o .
. o o.".o o . . o o.".o o . . o o.".o o .
. | . . | . . | .
/ | \ / | \ / | \
: | : : | : : | :
: | : : | : : | :
\:/ | \:/ \:/ | \:/ \:/ | \:/
~ | ~ ~ | ~ ~ | ~
[4] o o | o o [5] [4] o o | o o [5] [4] o o | o o [5]
o_0_o | o_0_o o_0_o | o_0_o o_0_o | o_0_o
o~0~o | o~0~o o~0~o | o~0~o o~0~o | o~0~o
o o ) | ( o o o o ) | ( o o o o ) | ( o o
/ | \ / | \ / | \
/ | \ / | \ / | \
/ | \ / | \ / | \
/ | \ / | \ / | \
/ o \ / o \ / o \
/ [1] \ / [1] \ / [1] \
o o o o o o
[1] [1] [1] [1] [1] [1]
Diagram Outline
1.Incoming Neutron
2.Uranium-235
3.Uranium-236
4.Barium Atom
5.Krypton Atom
Uranium
Uranium is a heavy metal, heavier than gold, and not only does it have
the largest atoms of any natural element, the atoms that comprise
Uranium have far more neutrons than protons. This does not enhance
their capacity to split, but it does have an important bearing on their
capacity to facilitate an explosion.
There are two isotopes of Uranium. Natural Uranium consists mostly
of isotope U-238, which has 92 protons and 146 neutrons
(92+146=238). Mixed with this isotope, one will find a 0.6%
accumulation of U-235, which has only 143 neutrons. This isotope,
unlike U-238, has atoms that can be split, thus it is termed
"fissionable" and useful in making atomic bombs. Being that U-238 is
neutron-heavy, it reflects neutrons, rather than absorbing them like its
brother isotope, U-235. (U-238 serves no function in an atomic
reaction, but its properties provide an excellent shield for the U-235 in
a constructed bomb as a neutron reflector. This helps prevent an
accidental chain reaction between the larger U-235 mass and its
`bullet' counterpart within the bomb. Also note that while U-238 cannot
facilitate a chain-reaction, it can be neutron-saturated to produce
Plutonium (Pu-239). Plutonium is fissionable and can be used in place
of Uranium-235 {albeit, with a different model of detonator} in an
atomic bomb.
Both isotopes of Uranium are naturally radioactive. Their bulky atoms
disintegrate over a period of time. Given enough time, (over 100,000
years or more) Uranium will eventually lose so many particles that it
will turn into the metal lead. However, this process can be
accelerated. This process is known as the chain reaction. Instead of
disintegrating slowly, the atoms are forcibly split by neutrons forcing
their way into the nucleus. A U-235 atom is so unstable that a blow
from a single neutron is enough to split it and henceforth bring on a
chain reaction. This can happen even when a critical mass is present.
When this chain reaction occurs, the Uranium atom splits into two
smaller atoms of different elements, such as Barium and Krypton.
When a U-235 atom splits, it gives off energy in the form of heat and
Gamma radiation, which is the most powerful form of radioactivity and
the most lethal. When this reaction occurs, the split atom will also
give off two or three of its `spare' neutrons, which are not needed to
make either Barium or Krypton. These spare neutrons fly out with
sufficient force to split other atoms they come in contact with. [See
chart below] In theory, it is necessary to split only one U-235 atom,
and the neutrons from this will split other atoms, which will split
more...so on and so forth. This progression does not take place
arithmetically, but geometrically. All of this will happen within a
millionth of a second.
The minimum amount to start a chain reaction as described above is
known as SuperCritical Mass. The actual mass needed to facilitate
this chain reaction depends upon the purity of the material, but for
pure U-235, it is 110 pounds (50 kilograms), but Uranium is never
quite pure, so in reality more will be needed.
Uranium is not the only material used for making atomic bombs.
Another material is the element Plutonium, in its isotope Pu-239.
Plutonium is not found naturally (except in minute traces) and is
always made from Uranium. The only way to produce Plutonium from
Uranium is to process U-238 through a nuclear reactor. After a period
of time, the intense radioactivity causes the metal to pick up extra
particles, so that more and more of its atoms turn into Plutonium.
Extraction
Uranium-235 is very difficult to extract. In fact, for every 25,000 tons of
Uranium ore that is mined from the earth, only 50 tons of Uranium
metal can be refined from that, and 99.3% of that metal is U-238
which is too stable to be used as an active agent in an atomic
detonation. To make matters even more complicated, no ordinary
chemical extraction can separate the two isotopes since both U-235
and U-238 possess precisely identical chemical characteristics. The
only methods that can effectively separate U-235 from U-238 are
mechanical methods.
Refinement
U-235 is slightly, but only slightly, lighter than its counterpart, U-238.
A system of gaseous diffusion is used to begin the separating process
between the two isotopes. In this system, Uranium is combined with
fluorine to form Uranium Hexafluoride gas. This mixture is then
propelled by low- pressure pumps through a series of extremely fine
porous barriers. Because the U-235 atoms are lighter and thus
propelled faster than the U-238 atoms, they could penetrate the
barriers more rapidly. As a result, the U-235's concentration became
successively greater as it passed through each barrier. After passing
through several thousand barriers, the Uranium Hexafluoride contains
a relatively high concentration of U-235 -- 2% pure Uranium in the
case of reactor fuel, and if pushed further could (theoretically) yield up
to 95% pure Uranium for use in an atomic bomb.
Once the process of gaseous diffusion is finished, the Uranium must
be refined once again. Magnetic separation of the extract from the
previous enriching process is then implemented to further refine the
Uranium. This involves electrically charging Uranium Tetrachloride gas
and directing it past a weak electromagnet. Since the lighter U-235
particles in the gas stream are less affected by the magnetic pull,
they can be gradually separated from the flow.
Following the first two procedures, a third enrichment process is then
applied to the extract from the second process. In this procedure, a
gas centrifuge is brought into action to further separate the lighter
U-235 from its heavier counter-isotope. Centrifugal force separates the
two isotopes of Uranium by their mass. Once all of these procedures
have been completed, all that need be done is to place the properly
molded components of Uranium-235 inside a warhead that will
facilitate an atomic detonation.
Detonation
Supercritical mass for Uranium-235 is defined as 110 lbs (50 kgs) of
pure Uranium.
Depending on the refining process(es) used when purifying the U-235
for use, along with the design of the warhead mechanism and the
altitude at which it detonates, the explosive force of the A-bomb can
range anywhere from 1 kiloton (which equals 1,000 tons of TNT) to 20
megatons (which equals 20 million tons of TNT -- which, by the way,
is the smallest strategic nuclear warhead we possess today. {Point in
fact -- One Trident Nuclear Submarine carries as much destructive
power as 25 World War II's}).
Plutonium
Plutonium will not start a fast chain reaction by itself, but this difficulty
is overcome by having a neutron source, a highly radioactive material
that gives off neutrons faster than the Plutonium itself. In certain types
of bombs, a mixture of the elements Beryllium and Polonium is used
to bring about this reaction. Only a small piece is needed. The
material is not fissionable in and of itself, but merely acts as a
catalyst to the greater reaction.
While Uranium is an ideally fissionable material, it is not the only one.
Plutonium can be used in an atomic bomb as well. By leaving U-238
inside an atomic reactor for an extended period of time, the U-238
picks up extra particles (neutrons especially) and gradually is
transformed into the element Plutonium.
Detonation
Plutonium is fissionable, but not as easily fissionable as Uranium.
While Uranium can be detonated by a simple 2-part gun-type device,
Plutonium must be detonated by a more complex 32-part implosion
chamber along with a stronger conventional explosive, a greater
striking velocity and a simultaneous triggering mechanism for the
conventional explosive packs. Along with all of these requirements
comes the additional task of introducing a fine mixture of Beryllium
and Polonium to this metal while all of these actions are occurring.
Supercritical mass for Plutonium is defined as 35.2 lbs (16 kgs). This
amount needed for a supercritical mass can be reduced to a smaller
quantity of 22 lbs (10 kgs) by surrounding the Plutonium with a U-238
casing.
Altimeter
An ordinary aircraft altimeter uses a type of Aneroid Barometer which
measures the changes in air pressure at different heights. However,
changes in air pressure due to the weather can adversely affect the
altimeter's readings. It is far more favorable to use a radar (or radio)
altimeter for enhanced accuracy when the bomb reaches Ground Zero.
While Frequency Modulated-Continuous Wave (FM CW) is more
complicated, the accuracy of it far surpasses any other type of
altimeter. Like simple pulse systems, signals are emitted from a radar
aerial (the bomb), bounced off the ground and received back at the
bomb's altimeter. This pulse system applies to the more advanced
altimeter system, only the signal is continuous and centered around a
high frequency such as 4200 MHz. This signal is arranged to steadily
increase at 200 MHz per interval before dropping back to its original
frequency.
As the descent of the bomb begins, the altimeter transmitter will send
out a pulse starting at 4200 MHz. By the time that pulse has returned,
the altimeter transmitter will be emitting a higher frequency. The
difference depends on how long the pulse has taken to do the return
journey. When these two frequencies are mixed electronically, a new
frequency (the difference between the two) emerges. The value of this
new frequency is measured by the built-in microchips. This value is
directly proportional to the distance travelled by the original pulse, so
it can be used to give the actual height.
In practice, a typical FM CW radar today would sweep 120 times per
second. Its range would be up to 10,000 feet (3000 m) over land and
20,000 feet (6000 m) over sea, since sound reflections from water
surfaces are clearer.
The accuracy of these altimeters is within 5 feet (1.5 m) for the higher
ranges. Being that the ideal airburst for the atomic bomb is usually set
for 1,980 feet, this error factor is not of enormous concern.
The high cost of these radar-type altimeters has prevented their use in
commercial applications, but the decreasing cost of electronic
components should make them competitive with barometric types
before too long.
Air Pressure Detonator
The air pressure detonator can be a very complex mechanism, but for
all practical purposes, a simpler model can be used. At high altitudes,
the air is of lesser pressure. As the altitude drops, the air pressure
increases. A simple piece of very thin magnetized metal can be used
as an air pressure detonator. All that is needed is for the strip of metal
to have a bubble of extremely thin metal forged in the center and have
it placed directly underneath the electrical contact which will trigger
the conventional explosive detonation. Before setting the strip in place,
push the bubble in so that it will be inverted.
Once the air pressure has achieved the desired level, the magnetic
bubble will snap back into its original position and strike the contact,
thus completing the circuit and setting off the explosive(s).
Detonating Head
The detonating head (or heads, depending on whether a Uranium or
Plutonium bomb is being used as a model) that is seated in the
conventional explosive charge(s) is similar to the standard-issue
blasting cap. It merely serves as a catalyst to bring about a greater
explosion. Calibration of this device is essential. Too small of a
detonating head will only cause a colossal dud that will be doubly
dangerous since someone's got to disarm and re-fit the bomb with
another detonating head. (an added measure of discomfort comes
from the knowledge that the conventional explosive may have
detonated with insufficient force to weld the radioactive metals. This
will cause a supercritical mass that could go off at any t
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