The Discovery of Fission The Manhattan Project An Overview Prepared by Dr. Chris McGowan Dean, College of Science, Technology and Agriculture Southeast.

The Discovery of FissionThe Discovery of FissionThe Manhattan ProjectThe Manhattan Project

An OverviewAn Overview

Prepared by Dr. Chris McGowanPrepared by Dr. Chris McGowan

Dean, College of Science, Technology and AgricultureDean, College of Science, Technology and Agriculture

Southeast Missouri State UniversitySoutheast Missouri State University

Henri BecquerelHenri Becquerel

Discovered Discovered Radioactivity in 1896.Radioactivity in 1896.

Observed that Observed that Uranium salts would Uranium salts would expose photographic expose photographic film even when film even when covered with opaque covered with opaque paper.paper.

Pierre and Pierre and Marie CurieMarie Curie

Began work on the Began work on the new radioactivity.new radioactivity.

Discovered Radium Discovered Radium and Polonium.and Polonium.

Marie is the only Marie is the only person to win two person to win two Nobel Prizes in two Nobel Prizes in two different scientific different scientific fields.fields.

Types of RadiationTypes of Radiation

Alpha, Alpha, 4422αα, a helium nucleus, , a helium nucleus,

massive, easily stopped by skin.massive, easily stopped by skin. Beta, Beta, 00

-1-1ββ, an electron, low mass, can , an electron, low mass, can penetrate skin.penetrate skin.

Gamma, Gamma, 0000γγ, light with energies , light with energies

overlapping with x-rays, no mass, overlapping with x-rays, no mass, can penetrate through body.can penetrate through body.

James ChadwickJames Chadwick

Discovered the neutron Discovered the neutron in 1932.in 1932.

The neutron is a particle The neutron is a particle that has the same mass that has the same mass as a proton with zero as a proton with zero charge.charge.

Frederic and Irene Frederic and Irene Joliot-CurieJoliot-Curie

27271313Al + Al + 44

22αα → → 30301515P + P + 11

00nn

Discovered Artificial Discovered Artificial Radioactivity.Radioactivity.

Missed fission.Missed fission.

Enrico FermiEnrico Fermi

Bombarded almost Bombarded almost every element in the every element in the Periodic Table with Periodic Table with neutrons.neutrons.

Also missed fission.Also missed fission. Defected to the US Defected to the US

when he accepted when he accepted the Nobel Prize.the Nobel Prize.

Lise Meitner, Otto Hahn, Lise Meitner, Otto Hahn, Fritz StrassmanFritz Strassman

Meitner and Hahn and had worked Meitner and Hahn and had worked together for several years on various together for several years on various aspects of radioactivity. They also aspects of radioactivity. They also were bombarding uranium with were bombarding uranium with neutrons trying to make transuranic neutrons trying to make transuranic elements.elements.

Meitner was Jewish and fled Germany Meitner was Jewish and fled Germany in 1938. She first went to Holland, in 1938. She first went to Holland, then to Copenhagen where Niels Bohr then to Copenhagen where Niels Bohr worked, and ultimately to Sweden. worked, and ultimately to Sweden.

Meitner and Hahn were in daily Meitner and Hahn were in daily contact through the mail and contact through the mail and continued to collaborate.continued to collaborate.

In one experiment, Hahn and In one experiment, Hahn and

Strassman were trying to isolate a Strassman were trying to isolate a new element they thought would be new element they thought would be similar to barium by trying to co-similar to barium by trying to co-precipitate the new element with precipitate the new element with barium carbonate.barium carbonate.

At the end of a paper they stated that At the end of a paper they stated that the element appeared to be barium.the element appeared to be barium.

The paper was picked up on Dec. 22, The paper was picked up on Dec. 22, 1938 by Paul Rosbaud and published 1938 by Paul Rosbaud and published Jan. 6, 1939.Jan. 6, 1939.

Paul RosbaudPaul Rosbaud Director of Springer Director of Springer

Verlagen, the Verlagen, the publisher of publisher of Naturewissenshaften.Naturewissenshaften.

Was a British Secret Was a British Secret Service operative code Service operative code named “The Griffin”.named “The Griffin”.

Another paper was Another paper was supposed to be supposed to be published but he had published but he had it switched for the it switched for the Hahn and Strassman Hahn and Strassman paper.paper.

Otto FrischOtto Frisch

Lise Meitner’s nephew Lise Meitner’s nephew who worked with Bohr.who worked with Bohr.

On Xmas Eve, 1938, he On Xmas Eve, 1938, he and Meitner figured and Meitner figured out that Hahn and out that Hahn and Strassman had split Strassman had split the uranium atom.the uranium atom.

They recognized the They recognized the huge amount of energy huge amount of energy that was released.that was released.

E=mcE=mc22

As a result of the Theory of Relativity, As a result of the Theory of Relativity, 1905, Albert Einstein had proposed that 1905, Albert Einstein had proposed that matter could be converted to energy matter could be converted to energy and energy to matter.and energy to matter.

If this proved accurate, then the energy If this proved accurate, then the energy produced by the fission of one uranium produced by the fission of one uranium atom would be over 1000 times that atom would be over 1000 times that produce by burning one carbon atom.produce by burning one carbon atom.

Chain Reaction (?)Chain Reaction (?)

The following is an example of one of The following is an example of one of the many possible fission reactions.the many possible fission reactions.

Fission products are very radioactive Fission products are very radioactive as they have far too many neutrons in as they have far too many neutrons in their nuclei.their nuclei.

1100n + n + 235235

9292U U → → 1421425656Ba + Ba + 9191

3636Kr + 3 Kr + 3 1100nn

Niels BohrNiels Bohr Brought news of Brought news of

fission to the US at the fission to the US at the Fifth Washington Fifth Washington Conference on Conference on Theoretical Physics.Theoretical Physics.

Several researchers Several researchers went back to their labs went back to their labs and confirmed the and confirmed the work and reported work and reported back before the back before the conference was over.conference was over.

Leo Szilard Leo Szilard andand

Albert Albert EinsteinEinstein

Szilard Composed a letter to Franklin Szilard Composed a letter to Franklin Roosevelt.Roosevelt.

Einstein signed the letter dated Aug. 2, Einstein signed the letter dated Aug. 2, 1939.1939.

This letter leads ultimately to the This letter leads ultimately to the Manhattan Project which began in 1942.Manhattan Project which began in 1942.

Glenn SeaborgGlenn Seaborg

Discovered Discovered plutonium at U.C. plutonium at U.C. Berkeley, Feb. Berkeley, Feb. 23, 1941.23, 1941.

239239Pu also Pu also undergoes fission undergoes fission and is made from and is made from 238238U.U.

Plutonium ProductionPlutonium Production

2382389292U + U + 11

00n n → → 2392399292UU

2392399292U → U → 239239

9393Np + Np + 00-1-1ββ t t1/21/2= 23.5 min= 23.5 min

2392399393Np → Np → 239239

9494Pu + Pu + 00-1-1β β t t1/21/2= 2.35 = 2.35

daysdays

General Leslie General Leslie GrovesGroves

Military Director Military Director of the Manhattan of the Manhattan Project.Project.

Famous for Famous for building the building the PentagonPentagon

Wanted to be a Wanted to be a field generalfield general

J. Robert J. Robert OppenheimerOppenheimer

Scientific Director of Scientific Director of the Manhattan the Manhattan Project.Project.

A physicist at UC A physicist at UC BerkeleyBerkeley

Dated a woman who Dated a woman who was a member of was a member of the communist party the communist party

Iowa State Iowa State CollegeCollege

Frank Spedding Frank Spedding Purified uranium Purified uranium metal.metal.

Over two million Over two million tons of uranium tons of uranium were produced in a were produced in a clapboard building clapboard building known as “Little known as “Little Ankeny”.Ankeny”.

University of University of ChicagoChicago

Enrico Fermi built the first nuclear Enrico Fermi built the first nuclear reactor, CP-1, in a squash court under reactor, CP-1, in a squash court under the football stadium. The first sustained the football stadium. The first sustained chain reaction occurred on Dec. 2, 1942.chain reaction occurred on Dec. 2, 1942.

Nuclear ReactorsNuclear Reactors

Fuel – fissionable material usually Fuel – fissionable material usually enriched enriched 235235U. CP-1 used uranium U. CP-1 used uranium metal from Iowa State.metal from Iowa State.

Moderator – slows down the neutrons Moderator – slows down the neutrons usually graphite, heavy water, or usually graphite, heavy water, or water. CP-1 used graphite.water. CP-1 used graphite.

Control Rods – absorb neutrons Control Rods – absorb neutrons usually boron or cadmium. CP-1 usually boron or cadmium. CP-1 used cadmium.used cadmium.

Oak RidgeOak Ridge

Secret City on the Clinch River near Secret City on the Clinch River near Knoxville, Tennessee.Knoxville, Tennessee.

Primary purpose was to enrich Primary purpose was to enrich 235235U.U. Also built a graphite reactor at X-10 Also built a graphite reactor at X-10

to study the production of plutonium.to study the production of plutonium.

X-10X-10

Y-12Y-12 Magnetic separation of Magnetic separation of 235235U from U from 238238U at Oak Ridge.U at Oak Ridge. The work was overseen by E. O. Lawrence from U. The work was overseen by E. O. Lawrence from U.

C. Berkeley.C. Berkeley.

K-25K-25

Gaseous diffusion plant at Oak Ridge Gaseous diffusion plant at Oak Ridge for enrichment of for enrichment of 235235U.U.

Based on Graham’s Law of Effusion Based on Graham’s Law of Effusion and the oddity that UFand the oddity that UF66 is a gas. is a gas.

HanfordHanford

Secret City on the Columbia River in Secret City on the Columbia River in Washington State.Washington State.

A series of nuclear reactors designed A series of nuclear reactors designed to produce plutonium.to produce plutonium.

A chemical plant to purify plutonium.A chemical plant to purify plutonium.

Los Los AlamosAlamos

Secret City in the Sangre de Christo Secret City in the Sangre de Christo Mountains in New Mexico.Mountains in New Mexico.

The purpose was to design and build The purpose was to design and build the bombs.the bombs.

Tickling the Tickling the Tail of the Tail of the

DragonDragon

The exact size of The exact size of the critical mass the critical mass was determined by was determined by Otto Frisch at Los Otto Frisch at Los Alamos.Alamos.

Klaus FuchsKlaus Fuchs

Born in Germany and Born in Germany and came to Los Alamos as came to Los Alamos as part of the British part of the British MissionMission

Worked on the explosive Worked on the explosive lenslens

An ardent communist An ardent communist who leaked information who leaked information to the Russiansto the Russians

Gun Gun DesignDesign

This design worked with uranium.This design worked with uranium. A 2000 lb TNT Blockbuster bomb was A 2000 lb TNT Blockbuster bomb was

used as the “trigger”.used as the “trigger”.

Implosion Implosion DesignDesign

This design was required for plutonium.This design was required for plutonium. Impurities of Impurities of 240240Pu would release too many Pu would release too many

neutrons and cause premature detonation in neutrons and cause premature detonation in the gun design. This would lower the yield.the gun design. This would lower the yield.

Trinity SiteTrinity Site

The gun design was simple and the The gun design was simple and the scientists did not feel that testing scientists did not feel that testing was necessary.was necessary.

The implosion device was much more The implosion device was much more complicated and needed to be complicated and needed to be tested.tested.

The chosen site was in the Jornado The chosen site was in the Jornado del Muerto Valley near Alamogordo del Muerto Valley near Alamogordo New Mexico and code named Trinity.New Mexico and code named Trinity.

GadgetGadget

The Dawn of The Dawn of the Nuclear the Nuclear

AgeAge

The first nuclear The first nuclear explosion occurred explosion occurred at 5:29:45 am on at 5:29:45 am on July 16, 1945 at July 16, 1945 at Trinity.Trinity.

Edward Teller described wearing double Edward Teller described wearing double welders glasses and was not impressed until welders glasses and was not impressed until he removed his hands from around the he removed his hands from around the glasses.glasses.

Fermi was holding pieces of paper in his hand Fermi was holding pieces of paper in his hand and waited for the shock wave to estimate and waited for the shock wave to estimate the output. He later commented on missing the output. He later commented on missing both fission and the first nuclear explosion.both fission and the first nuclear explosion.

To Use or Not to UseTo Use or Not to Use With the end of the war in Europe on May With the end of the war in Europe on May

8, 1945, discussion began on whether or 8, 1945, discussion began on whether or not to use the bombs.not to use the bombs.

Japan had never been a threat to develop Japan had never been a threat to develop a bomb.a bomb.

Groves definitely wanted to use the Groves definitely wanted to use the bombs.bombs.

Szilard started a petition, signed by many Szilard started a petition, signed by many of the scientists involved in the project, to of the scientists involved in the project, to not drop the bombs. The petition was not drop the bombs. The petition was never delivered to Truman.never delivered to Truman.

509509thth Composite Composite

GroupGroup

B-29 Bomber Group was constituted and B-29 Bomber Group was constituted and refitted to carry the atomic bombs.refitted to carry the atomic bombs.

Special training took place stateside Special training took place stateside before transferring to Tinian Island.before transferring to Tinian Island.

The commander was Colonel Paul The commander was Colonel Paul TibbetsTibbets

Little Boy and Fat ManLittle Boy and Fat Man

HiroshimHiroshimaa

Aug. 6, 1945, Little Boy was dropped by Aug. 6, 1945, Little Boy was dropped by the Enola Gay piloted by Col. Paul Tibbets.the Enola Gay piloted by Col. Paul Tibbets.

Equivalent to 12-15 kilotons of TNT.Equivalent to 12-15 kilotons of TNT. 70,000 immediate deaths, 140,000 by the 70,000 immediate deaths, 140,000 by the

end of the year.end of the year.

NagasakiNagasaki

August 9, 1945, Fat Man was droped by August 9, 1945, Fat Man was droped by Bocks Car piloted by Maj. Charles Sweeney.Bocks Car piloted by Maj. Charles Sweeney.

Equivalent to 21 kilotons of TNT.Equivalent to 21 kilotons of TNT. 40,000 immediate deaths, 70,000 by the 40,000 immediate deaths, 70,000 by the

end of the year.end of the year.

VJ-DayVJ-Day

Japan surrenders Japan surrenders unconditionally unconditionally on Aug. 14, 1945.on Aug. 14, 1945.

Surrender signed Surrender signed in Tokyo Harbor in Tokyo Harbor aboard the USS aboard the USS Missouri on Sept. Missouri on Sept. 2.2.

After the WarAfter the War

The US conducts tests on Bikini Atoll.The US conducts tests on Bikini Atoll. Able test recreated a Pearl Harbor style Able test recreated a Pearl Harbor style

attack using a single plutonium bomb.attack using a single plutonium bomb. Today, you can dive on some of the Today, you can dive on some of the

sunken ships in the lagoon.sunken ships in the lagoon. The Bikinians cannot yet return.The Bikinians cannot yet return.

Art work by Grant PowellArt work by Grant Powell

Edward Edward TellerTeller

Edward Teller Edward Teller pushed for pushed for further work on further work on a fusion based a fusion based bomb.bomb.

Known as the Known as the Father of the Father of the Hydrogen Bomb.Hydrogen Bomb.

Stanislaw Stanislaw UlamUlam

Recognized that Recognized that radiation could radiation could create the create the pressure that pressure that would cause would cause fusion.fusion.

Led to the design Led to the design of a staged of a staged thermonuclear thermonuclear device.device.

The Fusion The Fusion ReactionReaction

Requires a Requires a plutonium plutonium bomb as a bomb as a trigger.trigger.

MikeMike

First staged fusion explosion occurred on First staged fusion explosion occurred on Eniwetok Atoll on Nov. 1, 1952.Eniwetok Atoll on Nov. 1, 1952.

Mike used liquid deuterium as a fuel.Mike used liquid deuterium as a fuel. The output of 10.4 megatons of TNT The output of 10.4 megatons of TNT

exceeded all of the explosives used in exceeded all of the explosives used in WW II including both atomic bombs.WW II including both atomic bombs.

Modern Thermonuclear Modern Thermonuclear WarheadWarhead

Modern weapons use LiD as a fuel.Modern weapons use LiD as a fuel. As many as 20 warheads may sit on As many as 20 warheads may sit on

a single ICBM.a single ICBM.

The United States is the The United States is the only country to have used a only country to have used a nuclear weapon in anger.nuclear weapon in anger.

Fat Man and Mike Fat Man and Mike superimposedsuperimposed

over New York City over New York City