Реферат на тему ABombA Essay Research Paper Atom bomb nuclear
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A-Bomb(A) Essay, Research Paper
Atom bomb nuclear weapon manhattan project albert einsteinJust before the beginning of World War II, Albert Einstein wrote a letter to President Franklin D. Roosevelt. Urged by Hungarian-born physicists Leo Szilard, Eugene Wingner, and Edward Teller,Einstein told Roosevelt about Nazi German efforts to purify Uranium-235 which might be used tobuild an atomic bomb. Shortly after that the United States Government began work on theManhattan Project. The Manhattan Project was the code name for the United States effort todevelop the atomic bomb before the Germans did. “The first successful experiments in splitting auranium atom had been carried out in the autumn of 1938 at the Kaiser Wilhelm Institute inBerlin”(Groueff 9) just after Einstein wrote his letter. So the race was on. Major General WilhelmD. Styer called the Manhattan Project “the most important job in the war . . . an all-out effort tobuild an atomic bomb.”(Groueff 5) It turned out to be the biggest development in warfare andscience’s biggest development this century. The most complicated issue to be addressed by the scientists working on the Manhattan Projectwas “the production of ample amounts of ‘enriched’ uranium to sustain a chain reaction.”(Outlaw 2)At the time, Uranium-235 was hard to extract. Of the Uranium ore mined, only about 1/500 th ofit ended up as Uranium metal. Of the Uranium metal, “the fissionable isotope of Uranium(Uranium- 235) is relatively rare, occurring in Uranium at a ratio of 1 to 139.”(Szasz 15)Separating the one part Uranium-235 from the 139 parts Uranium-238 proved to be a challenge. “No ordinary chemical extraction could separate the two isotopes. Only mechanical methodscould effectively separate U-235 from U-238.”(2) Scientists at Columbia University solved thisdifficult problem. A “massive enrichment laboratory/plant”(Outlaw 2) was built at Oak Ridge, Tennessee. H. C. Urey, his associates, and colleagues at Columbia University designed a system that “worked onthe principle of gaseous diffusion.”(2) After this process was completed, “Ernest O. Lawrence(inventor of the Cyclotron) at the University of California in Berkeley implemented a processinvolving magnetic separation of the two isotopes.”(2) Finally, a gas centrifuge was used to furtherseparate the Uranium-235 from the Uranium-238. The Uranium-238 is forced to the bottombecause it had more mass than the Uranium-235. “In this manner uranium-235 was enriched fromits normal 0.7% to weapons grade of more than 90%.”(Grolier 5)This Uranium was then transported to “the Los Alamos, N. Mex., laboratory headed by J. RobertOppenheimer.”(Grolier 5) “Oppenheimer was the major force behind the Manhattan Project. Heliterally ran the show and saw to it that all of the great minds working on this project made theirbrainstorms work. He oversaw the entire project from its conception to its completion.”(Outlaw 3)Once the purified Uranium reached New Mexico, it was made into the components of a gun-typeatomic weapon. “Two pieces of U-235, individually not large enough to sustain a chain reaction,were brought together rapidly in a gun barrel to form a supercritical mass that explodedinstantaneously.”(Grolier 5) “It was originally nicknamed ‘Thin Man’(after Roosevelt, but laterrenamed ‘Little Boy’ (for nobody) when technical changes shortened the proposed gunbarrel.”(Szasz 25) The scientists were so confident that the gun-type atomic bomb would work”no test was conducted, and it was first employed in military action over Hiroshima, Japan, onAug. 6, 1945.”(Grolier 5)Before the Uranium-235 “Little Boy” bomb had been developed to the “point of seeming assuredof success,”(Grolier 5) another bomb was proposed. The Uranium-238 that had been earlier ruledout as an option was being looked at. It could capture a free neutron without fissioning andbecome Uranium-239. “But the Uranium-239 thus produced is unstable (radioactive) and decaysfirst to neptunium-239 and then to plutonium-239.”(Grolier 5) This proved to be useful becausethe newly created plutonium-239 is fissionable and it can “be separated from uranium by chemicaltechniques,”(6) which would be far simpler than the physical processes to separate theUranium-235 from the Uranium-238. Once again the University of Chicago, under Enrico Fermi’s direction built the first reactor. “Thisled to the construction of five large reactors at Hanford, Wash., where U-238 was irradiated withneutrons and transmuted into plutonium.”(6) The plutonium was sent to Los Alamos. The problem to overcome in the development of the plutonium bomb was an isotope of plutonium. The scientists feared this isotope would cause premature detonation and most of the plutoniumwould blow apart before it could all fission. “To overcome this so-called ‘defect of nature, ‘ theplutonium had to be brought into a supercritical mass far faster than conventional ballistics couldachieve.”(Grolier 6)Physicist Seth Neddermeyer and mathematician John von Neumann devised the theory of”implosion.” A subcritical sphere of plutonium was surrounded by chemical high-explosives. The5,300 pounds of explosives were all “carefully shaped as ‘lenses.’ When these were detonated,they focused the blast wave so as to compress the plutonium instantly into a supercriticalmass.”(Szasz 25) This was much more complex, and many people doubted that it would work. There was a debate at Los Alamos about whether to test the new plutonium ‘implosion’ bombbefore it was actually dropped. “Harvard explosives expert George B. Kistiakowsky andOppenheimer both argued for such a test, but initially Groves was opposed. He was afraid that ifthe test failed, the precious plutonium would be scattered all across the countryside.”(Szasz 26)Brigadier General Leslie R. Groves, the man the army placed in charge, was eventually persuaded. Hanford’s plutonium production was increasing fast enough so that a test would cause little delay intime. They feared that if they dropped the untested plutonium bomb and it failed to work, “theenemy would find themselves owners of a ‘gift’ atomic weapon.”(Szasz 26) The final agreement forthe test was that the bomb would be placed in “a gigantic, 214-ton, cylinder-shaped tank (called’Jumbo’).”(Szasz 26) If the plutonium correctly fissioned, the tank would be vaporized. If it did notwork correctly, the conventional explosives would be contained in the tank and the plutoniumwould stay in the tank. After further development of the implosion design and fears that “Jumbo”would dramatically distort all “their complicated instrumentation-the raison d’ tre for thetest,”(Szasz 36) the world’s largest pressure tank was not used. On Monday, July 16, 1945, at 5:29:45 A.M., Mountain War Time, the plutonium bomb ignited atthe Trinity site, a remote site in the New Mexico desert. “The explosion created s brilliant flash thatwas seen in three states.”(Szasz 83) There were many reports from civilians from all over thatdescribed the experience. People who saw it said it looked like the sun had risen for a few minutesand then went back down. Others thought they had seen a large plane or meteor crash. A sheepherder who was laying sleeping on a cot fifteen miles away was blown off. “The SmithsonianObservatory on Burro Mountain confirmed a shock but noted that the vibrations were unlike anyearthquake ever recorded.”(Szasz 84) An eight year-old boy was awakened and ran for hisMethodist parents, and they considered if this might be the end of the world. The most powerful statement that has been cited in practically every coverage of the atomic bombis Georgia Green’s experience. She was being driven to Albuquerque. “What was that?” she askedher brother-in-law, who was driving. This was very unusual because Georgia Green was blind. Brigadier General Farrell wrote a letter for the Secretary of War. “‘No man-made phenomenon ofsuch tremendous power had ever occurred before . . . Thirty seconds after the explosion came,first, the air blast pressing hard against people and things, to be followed almost immediately by thestrong, sustained, awesome roar which warned of doomsday and made us feel that we puny thingswere blasphemous to dare tamper with forces heretofore reserved to the Almighty. Words areinadequate tools for the job of acquainting those not present with the physical, mental andpsychological effects.”(Groueff 355)Upon witnessing the explosion, reactions among the bomb’s creators were mixed. Their missionhad been successfully accomplished, however, they questioned whether “the equilibrium in naturehad been upset — as if humankind had become a threat to the world it inhabited.”(Outlaw 3)Oppenheimer was ecstatic about the success of the bomb, but quoted a fragment from BhagavadGita. “I am become Death, the destroyer of worlds.” Many people who were involved in thecreation of the atomic bomb signed petitions against dropping the bomb. The atomic bomb has been used twice in warfare. The Uranium bomb nicknamed “Little Boy,”which weighed over 4.5 tons, was dropped over Hiroshima on August 6, 1945. At 0815 hoursthe bomb was dropped from the Enola Gay. It missed Ground Zero at 1,980 feet by only 600feet. “At 0816 hours, in the flash of an instant, 66,000 people were killed and 69,000 people wereinjured by a 10 kiloton atomic explosion.”(Outlaw 4) [See blast ranges diagram]Nagasaki fell to the same treatment as Hiroshima on August 9, 1945. The plutonium bomb, “FatMan,” was dropped on the city. It missed its intended target by over one and a half miles. “Nagasaki’s population dropped in one split-second from 422,000 to 383,000. 39,000 werekilled, over 25,000 were injured. That blast was less than 10 kilotons as well. Physicists who havestudied the atomic explosions conclude that the bombs utilized “only 0.1% of their respectiveexplosive capabilities.”(Outlaw 4)Controversy still exists about dropping the two atomic bombs on Japan. Arguments defending theJapanese claim “the atomic bomb did not win the war in the Pacific; at best, it hastened Japaneseacceptance of a defeat that was viewed as inevitable.”(Grolier 8) Other arguments state that theUnited States should have warned the Japanese, or that we should have invited them to a publicdemonstration. “In retrospect that U.S. use of the atomic bomb may have been the first act of thecold war.”(Grolier 8) On the other side, advocates claimed that the invasion of the Japaneseislands could and would result in over one million military casualties plus the civilian losses basedon previous invasions of Japanese occupied islands. ============================================================================ – Diagram for Plutonium Bomb – ——————————– [Gravity Bomb - Implosion Model] ——————————– -> Cutaway Sections Visible ============================================================================ / / / _________________/_______________________ | : ||: : | [2]——-> | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | :______||:_____________________________: | |/_______||/______________________________| | : |:| / | | : |:| / | | :__________|:| / |:_ | :__________:| / |___ |______________| / | | / |_______|__________________/ |_____________________________| / / / / _______________ / ___/ ___ /____ __/ __ ____ [3]_______________________________ ___| / __/ __ / / / / / ___________ / / __/_____________ ./ /__ ___ /================= ___ __ . [4]——-> ___||___|====|[[[[[|||||||]]]]]|====|___||___ / / |=o=o=o=o=o=o=o=o=| .’ / _______ _______/ `. : |___ |*| ___| : .’ | _________________ |*| _________________/ | `. : | ___________ ___ |*| / ___ ___________ | : : |__/ / _*//_/ / __| : : |______________:|:____:: **::****:|:******** .’ /:|||||||||||||’`|;..:::::::::::..;|’`|||||||*|||||: `. [7]———-> ||||||’ .:::; | ___ | ;:::. `|||||*|| : |:|||||||||’ .::’ ..:::::::::::.. /`::. `|||*|||||:| : : |:|||||||’ .::’ .:::” “:::. `::. `|***|:| : : |:|||||’ .:: .::” | [9] | /“::: /::. `|||*|:| : [8]————>::’ .::’ |_________|/ `::: `::. `|* `. |’ .::’ ::’ [9] . . . [9] /::: `::. *|:/ .’ : :’ :::’.::’ . . / `::.`::: *:/ : : | .::’.::’____ [10] . [10] /____`::.`::.*| : : | ::: ::: | . . . | ::: :::*| :
: | ::: :: [9] | . . ..:.. . . | [9] :: :::*| : : ::: :: | . :_____________________________[11] `. `:: ::: ____| . . . |____ ::: ::’/ .’ : :; `::. / . [10] [10] . .::’ ::/ : `. :. `::. / . . . .::’ .:/ .’ : :. `:::/ [9] _________ [9] :::’ .:/ : `. ::. `:::. /| | .:::’ .::/ .’ : :/ `:::./ | [9] | .:::’ :/ : `:=========::. `::::… …::::’ .::/=========:’ `: ::./ “`:::::::::”’ .::/ :’ `. | |/ .’ `. :::…:::/ .’ `. .’ `. .’ `:. .:’ `::. .::’ `::.. ..::’ `:::.. ..:::’ `::::::… ..::::::’ [12]——————> `:____:::::::::::____:’ “`::::_____::::”’ ============================================================================ – 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) ============================================================================ [Gravity Bomb Model] —————————- -> Cutaway Sections Visible / / / _________________/_______________________ | : ||: : | [2]——-> | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | : ||: : | | :______||:_____________________________: | |/_______||/______________________________| | | / | | | / | | | / | | | / |___ |______________| / | | / |_______|__________________/ |_____________________________| / / _________________ / _/ _ / __/ __ / / /__ _/ _ __ [3]_______________________________ _| / / / / / / / ___________ | / __/_____________ | | |_ ___ /================= ___ _| | [4]———> _||___|====|[[[[[[[|||]]]]]]]|====|___||_ | | |—————–| | | | | |o=o=o=o=o=o=o=o=o| | | _______________/ | | | |__ |: __| | | | ______________ |: ______________/ | | | | ________________|: /________________ | | | |/ |::::|: ::::| | | [6]———————-> |::::|: ::::| | | |::::|: ::::| | | | | |::==|: == | | |::__: :/__::| | | | | |:: : : ::| | | [7]—————————-> _/ ::| | | | | ________/ |:: ::|/ ________/ | | | | ||:: | |_/ _/|::_ _ _ _ _::|_/ _| | [9]————————–>_=_=_=_=_::| | | | | :::._______.::: | | | | .:::| |:::.. | | | | ..:::::’| |`:::::.. | | [6]—————->.::::::’ || || `::::::. | | .::::::’ | || || | `::::::. | | /| | .::::::’ | || || | `::::::. | | | | | .:::::’ | || | | |.:::::’ | || || | `:::::.| | | | ||::::’ | |`. .’| | `::::|| | [11]___________________________ “ ” __________________________[11] : | | :: / ::/ | | | | | :_________|_|/__ __/|_|_________:/ | | / | | | __________ ___:___ __________ | | | || | | | | |:::::::| | | | | [12] /|: | | | | |:::::::| | | | | | / |: | | | | |:::::::| | | | | |—-> / /|: | | | | |:::::::| | / / |: | | | | |:::::::| | | | | | / |: | | | | |:::: | / /|: | | | | |:::::::| | | | | | / / |: | | | | `:::::::’ | | | | | _/ / /: : | | | `: “ ” :’ | | | | | / / .. | | |: `: :’ | | |->| / / : | | ::: `. .’ | |/ / ^ | ::::. `. .’ .:::: / | | /| | _::::::. `. .’ .::::::_/ | |_______| | ::::::. `. .’ .::: |_________:::::.. ` ….. ‘ ..:::::/_________| | ::::::::…….::::::::/ | | | `. .’ `. .’ `. .’ `:. .:’ `::. .::’ `::.. ..::’ `:::.. ..:::’ `::::::… ..::::::’ [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) === – Breakdown of the Atomic Bomb’s Blast Zones – ———————————————- . . . . . . . . [5] [4] [5] . . . . . . . . . . [3] _ [3] . . . [2] . . . _._ . . . . . . . [4] . .[2]. [1] .[2]. . [4] . . . . . . . -.- . . . [2] . . . [3] – [3] . . . . . . . [5] . [4] . [5] . . . . . . ============================================================================ – Diagram Outline – ——————— [1] Vaporization Point —————— Everything is vaporized by the atomic blast. 98% fatalities. Overpress=25 psi. Wind velocity=320 mph. [2] Total Destruction —————– All structures above ground are destroyed. 90% fatalities. Overpress=17 psi. Wind velocity=290 mph. [3] Severe Blast Damage ——————- Factories and other large-scale building collapse. Severe damage to highway bridges. Rivers sometimes flow countercurrent. 65% fatalities, 30% injured. Overpress=9 psi. Wind velocity=260 mph. [4] Severe Heat Damage —————— Everything flammable burns. People in the area suffocate due to the fact that most available oxygen is consumed by the fires. 50% fatalities, 45% injured. Overpress=6 psi. Wind velocity=140 mph. [5] Severe Fire & Wind Damage ————————- Residency structures are severely damaged. People are blown around. 2nd and 3rd-degree burns suffered by most survivors. 15% dead. 50% injured. Overpress=3 psi. Wind velocity=98 mph. —————————————————————————- – Blast Zone Radii – ———————- [3 different bomb types]____________________________________________________________________________ ______________________ ______________________ ______________________ | | | | | | | -[10 KILOTONS]- | | -[1 MEGATON]- | | -[20 MEGATONS]- | |———————-| |———————-| |———————-| | Airburst – 1,980 ft | | Airburst – 8,000 ft | | Airburst – 17,500 ft | |______________________| |______________________| |______________________| | | | | | | | [1] 0.5 miles | | [1] 2.5 miles | | [1] 8.75 miles | | [2] 1 mile | | [2] 3.75 miles | | [2] 14 miles | | [3] 1.75 miles | | [3] 6.5 miles | | [3] 27 miles | | [4] 2.5 miles | | [4] 7.75 miles | | [4] 31 miles | | [5] 3 miles | | [5] 10 miles | | [5] 35 miles | | | | | | | |______________________| |______________________| |______________________|____________________________________________________________________________ Philip Shuman United States History Fourth Period June 9, 1995 Second Semester Term Paper Bibliography Szasz, Ferenc Morton. The Day The Sun Rose Twice. Albuquerque: University of New Mexico Press, 1956 Grolier Electronic Publishing, Inc. Academic American Encyclopedia. Copied from the PRODIGY service 05/16/95 20:16 1995 Batchelder, R.C. The Irreversible Decision. Houghton Mifflin Company Boston, The Riverside Press Cambridge, 1962 York, Herbert Frank. The Advisors: Oppenheimer, Teller, and The Superbomb. San Francisco: W.H. Freeman and Company, 1976 Taylor, Alan John Percivale. The Second World War. New York: G.P. Putnam’s Sons, 1975 Groueff, Stephane. Manhattan Project. Boston: Little, Brown and Company, 1967 Outlaw Labs. downloaded from P-80 Systems, 304-744-2253