Nuclear Holocaust in a Terrorist
Age
My Purpose
• To underscore the importance of keeping
track of weapons grade Uranium as a
deterrent to nuclear terrorism
• To explain how we are vulnerable to
sufficiently determined terrorists both at
home and abroad, who would seek to
smuggle weapons grade uranium fuel into
or out of our country.
My Purpose
• To highlight the problems created by the
downfall of the former Soviet Union.
The Science of Uranium and
Plutonium
• Uranium is one of the most abundant
elements in the Earth’s core.
– Mined as uranium ore “pitchblende”
– Element #92 (92 protons in its nucleus)
– Forms: several isotopes:
»
92U
238
–non fissionable (99%) – 146 neutrons
»
92U
235
– fissionable (0.7%) – 143 neutrons
The Science of Uranium and
Plutonium
– Pure uranium is
separated chemically
from pitchblende and
is available in
Fluorides, Oxides
(yellow cake) and
other forms
The Science of Uranium and
Plutonium
• Plutonium
– First isolated by Glenn T. Seaborg at U of Cal.
(Berkeley) in 1940.
– Many isotopes are known. Most particularly 94Pu239 (94
protons/145 neutrons)
– A warm metal because of radioactive decay. Used for
heating.
The Science of Uranium and
Plutonium
• Fission of Uranium
• To produce plutonium
238
239
92U
92U
239 +
93N
β-
239
94Pu
(half-life 24,100 years)
+ β-
The Science of Uranium and
Plutonium
• Radioactive Decay of
Uranium
• All fission products are
radioactive. Some with
half-lives of thousands
of years.
The Science of Uranium and
Plutonium
• How to separate
fissionable U235 from
non-fissionable U238
– Gaseous Diffusion
– Electromagnetic
separation
• Highly enriched U235
sufficient for making
bombs is >80%
(HEU)
The Science of Uranium and
Plutonium
• The Chain Reaction
– Primary neutrons
=>secondary neutrons
=>tertiary neutrons
– In each fission event,
mass is converted into
a very large amount of
energy
The Science of Uranium and
Plutonium
• The Chain Reaction
– Critical Mass
(density) is the
minimum mass
necessary for a
sustained
uncontrollable nuclear
chain reaction.
The Science of Uranium and
Plutonium
• How much do
we need to
make a bomb?
– A sustained
chain reaction
implies no more
than one
secondary
fission event per
primary fission
event (a nuclear
reactor)
Bomb
Type
Bare
Sphere
Bare
Sphere
(with
tamper)
235
U
92
(Kg)
239
P
94
(Kg)
56
11
15
5
History
• 6.6 Byr ago-Uranium is believed to be
formed in a supernova.
• 1789 Element 92 is discovered in
pitchblende by German pharmacist Martin
Heinrich Klaproth
History
• 1896- Uranium
discovered to be
radioactive by Antoine
Becquerel. Uranium is
named after the newly
discovered planet,
Uranus
History
• 1905-Albert Einstein
discovers famous
equation from special
relativity that speaks
of the equivalence of
mass and energy
E=mc2
History
• 1907 Ernest Rutherford
converts nitrogen to
oxygen in the first manmade nuclear reaction
• 1932-James Chadwick
proposes “the neutron”.
His ideas inspire Enrico
Fermi (US) and Otto
Hahn and Fritz
Straussman (Ger).
History
• 1938-1939: The idea
of a fission-induced
chain reaction is
conceived by Leo
Szilard. He begins
work with Fermi and
others at the
University of Chicago
Fermi
Szilard
History
• Bohr and other
leading scientists
have escaped Naziheld countries and
start to work for the
allies.
– Bohr expresses
concern that Nazis can
develop a nuclear
weapon.
History
• Szilard, Edward
Teller, and Einstein
collaborate on a letter
to President
Roosevelt advising
him of this capability.
This begins project
“Manhattan”.
History:The German Manhattan
Project
• Werhner Heisenberg
attempts Berman
bomb to split uranium.
– It is believed he did
not understand the
difference between a
reactor and a bomb
History:The German Manhattan
Project
• It is believed that the German project
failed for several reasons:
– Deliberate attempts to sabotage the projects
by scientists
– Many of Germany’s best scientists were
Jewish
•
•
•
•
Albert Einstein
Edward Teller
Niels Bohr
Enrico Fermi’s wife
History:The German Manhattan
Project
• It is believed that the German project
failed for several reasons:
– Lack of availability of HEU
• Stores in Finland and Norway were destroyed by
resistance and British commandos.
– The project was poorly organized and
research was decentralized.
History: The German Manhattan
Project
• September 1941, Niels
Bohr meets with
Heisenberg in
Copenhagen where
Heisenberg shares his
ideas.
• February 1942,
Heisenberg admits to
Nazi war minister Albert
Speer that a fission bomb
is not possible for many
years to come.
Nonetheless, the Nazis
begin work on a
dispersing bomb.
History: The Manhattan Project
• Dec. 6, 1941: US congress commits $2B to the
Manhattan Project
• 1940-1941: Plans are in full swing
– A HEU separation plant at Oak Ridge, Tenn.
– A Pu production facility at Hanover, Wash.
– Headquarters and main physics experiments at LANL
(a converted boys school), in Nevada.
– J. Robert Oppenheimer heads research on the project
after Einstein refuses. General Leslie Groves is in
charge.
– An entire military-industrial-and academic research
complex is created, which is still in existence.
History: Challenges to be
Overcome
• 1. How to purify the fuel?
–
92U
235
and 94Pu239 at Oak
Ridge
• Magnetic Separation:
(Calutrons) many wires
needed- “racetracks”
• Copper and Silver
borrowed from the US
Mint.
• 10% of all US electric
power used for 2 years
all to produce only 7g of
HEU.
• Final HEU used on
“Little Boy”
History: Challenges to be
Overcome
• The X-10 reactor at Oak
Ridge uses neutrons
released from U235 to
turn U238 into Pu. Similar
to reactors at Hanover.
• S-50 plant at Oak Ridge
separated the isotopes by
convection with steam
coming from the K-25
plant (right).
History: Challenges to be
Overcome
• 2. How to achieve
critical mass?
– The Gun approach
• HEU slugs are
slammed together at
high enough speeds in
a “gun” device.
• “Little Boy” dropped on
Hiroshima, Aug. 6,
1945 used 60 kg of
HEU
• Gun bombs may use
either U or Pu with a
tamper
History: Challenges to be
Overcome
• 2. How to achieve
critical mass?
– The Implosion
approach: Critical
density is achieved by
implosion of a shock
wave in a spherical
core similar to the
implosion of a massive
star to produce a
supernova
History: Challenges to be
Overcome
• 2. How to achieve critical
mass?
• The shock wave is
produced by detonation
of dynamite
• Because of the escape of
neutrons, implosion
devices may only use Pu.
• “Fat Man” dropped on
Nagasaki on Aug. 9,
1945; 6.2 kg of Pu; yield:
21-23 kT of TNT.
History: Challenges to be
Overcome
• “Gadget” –an implosion
bomb test detonation
atop a 150 ft tower on
July 16, 1945 in New
Mexico 210 miles from
Alamogordo in a place
called “Journada Del
Muerto” (Journey of
Death) code named
“Trinity”.
• Heat-radiation melted
sand created a new
mineral “Trinitite”.
Analysis of an Atomic Explosion
• In the first few milliseconds there is a bright flash
followed by an outward rushing shock wave
traveling at the speed of sound.
• Thermal X-Rays produced by either one of two
mechanisms
• Directly from decay of U235 or Pu239
• Indirectly by the slow down of electrons (β particles) which
are also direct by-products of decay.
Trinity explosion
Google Video
Analysis of an Atomic Explosion
• An atomic fireball or “mushroom cloud” is
created and rises.
• Outward flow of air is followed by inward
flow into ensuing firestorm.
• Debris from ground is lifted up into the
fir4eball then falls back to Earth as
“radioactive fallout”-the silent killer.
• Fireball rises into the air then dissipates.
History
• August 1945. Japan surrenders
History: Post WWII: The Cold War
Heats Up
• 1946: Work begins in a fusion bomb-the
hydrogen bomb.
• 1949: Soviet Union detonates their own
atomic explosion: Klaus Fuchs smuggles
secrets with help from Julius and Ether
Rosenberg. Fuchs is deported. The
Rosenbergs were executed.
History: Post WWII: The Cold War
Heats Up
• Edward Teller takes
over production of a
“hydrogen bomb”,
inappropriately called
the “Atomic Bomb” or
“A-Bomb”
History: Post WWII: The Cold War
Heats Up
• 9 May, 1951: “Operation Greenhouse”
produces “George” which confirmed that a
fission device could produce the
conditions necessary for a hydrogen
fusion bomb.
• 1 Nov. 1952: “Operation Ivy” produces
“Mike”, the first two-stage thermonuclear
fusion device: 1H2 + 1H3 => 2He4 + n
History: Post WWII: The Cold War
Heats Up
• 1950’s – 1960’s: New concepts in fission
primary and fusion secondaries
developed. Delivery systems changed
from planes to ICBM’s to MIRV’s.
• U.S. leads the world with over 1100 test
detonations.
History: Post WWII: The Cold War
Heats Up
• “Atoms for Peace” program: Both
superpowers agree to produce 100’s of
nuclear reactors for themselves and for 50
other nations.
• Export restrictions were lifter in response to
demands for longer-lived fuel.
• Reactors were supplied with bomb grade HEU
(≥80% 92U235)
• 10 Metric tons of HEU still resides in nations that
do not posses nuclear weapons. Enough for 150200 gun-type devices, as of 2005.
History: Post WWII: The Cold War
Heats Up
• 1957: IAEA organized as an independent
nuclear watchdog agency.
• 1963: “Limited Test Ban Treaty” limits
nuclear testing to underground where
detection methods are limited to seismic
studies and radioactive effluent in in the
air.
History: Post WWII: The Cold War
Heats Up
• 1968: “Nuclear Non-Proliferation Treaty”
limited the spread of nuclear weapons to 5
nations: U.S., Russia, U.K., France, and
China.
• 188 nation agree.
• Several rogue states have defied it (Israel, North
Korea, and Pakistan). Iran threatens to join the list.
History: Post WWII: The Cold War
Heats Up
• 1970’s: U.S. takes steps to prevent
diversion of bomb grade fuel.
• Conversion of American designed reactors to run
on LEU.
» 41 reactors to date have been retrofitted.
• High powered research reactors still need HEU.
• 1980’s: A new spirit of openness
“Glasnost” and “Perestroika”
History: The fall of the Soviet
Union: End of the Cold War
• 1991: The installation of democracy in for
former Soviet Union is greeted with
economic collapse.
• Many former members of the Soviet bloc
became independent states
(Turkmenistan, Uzbekistan, Belarus, …)
History: The fall of the Soviet
Union: End of the Cold War
• Soviet record keeping is very poor.
• 18 incidents of nuclear smuggling between 1993
and 2004 were reported by the IAEA.
• Incidents were reported only after material was
discovered, and so no one is exactly sure how
much if any HEU is missing.
• Breaches have been plainly evident.
• US works with Russia to secure some 600 tons of
HEU and 30,000 weapons.
What Is Happening Now? : The
Problem
• The Russian government appears
unconcerned about its lax security and
dangers posed by terrorists.
• Putins’ government is increasingly resistant to
visits by foreigners to its nuclear programs.
• 50 tons in civilian use support 140 reactors for
scientific and industrial use, and for medical
purposes.
• 50% in Russia alone, with much of this in or near
urban areas.
What Is Happening Now? : The
Problem
• Today, it is feared that Al-Qaeda might
acquire HEU and detonate a crude guntype device before authorities can
respond.
• 10 metric tons resides in nations that will not
develop nuclear weapons. This is enough for 150200 gun-type devices, as of 2005.
What Is Happening Now? : A TwoFold Solution
• 1. Eliminate the use of HEU wherever
possible.
• 2. Dilute all accumulated stocks with LEU
that is not useable in weapons.
• In the 1990’s U.S. begins to cooperate
with Russia in securing and eliminating
HEU stockpiles.
• Since 1999, US has been buying and
blending down 7 tons of civilian HEU.
What Is Happening Now? : A TwoFold Solution
• Some of this is spent reactor fuel, which is
80% HEU, but is still radioactive, and
therefore is “self-protective”.
• After 9/11, congress intensifies pressure o
the DOE to step up its efforts to secure
civilian HEU worldwide.
• Repatriate all used and unused Russian civilian
HEU by 2010
• Repatriate all spent US fuel by 2019
What Is Happening Now? : A TwoFold Solution
After 9/11, congress intensifies pressure o
the DOE to step up its efforts to secure
civilian HEU worldwide.
• Retrofit all US civilian research reactors to LEU
fuel by 2014
• Much progress has been made in retrofitting
Russian civilian reactors but more needs to be
done.
What Is Happening Now? : A TwoFold Solution
• The IAEA estimates that 80% of the world’s
aging research reactor fleet could be
decommissioned with HEU stores bringing in
approximately $20M/ton for dilution to LEU.
• “If the U.S. and its allies were to take seriously
the challenge of preventing nuclear terrorism,
civilian HEU could be eliminated …. in 5-8 years.
Continued delay in completing this task only
extends the window of opportunity to would-be
terrorists”
Glaser and Von Hippel: SciAm (2006)
What’s Happening Now?: Uranium
Smuggling: How Do We Stop It?
• The use of HEU overseas by foreign
governments is the responsibility of the
Department of Energy (DOE)
• Detection of nuclear smuggling is the
responsibility of the Department of
Homeland Security (DHS).
• We need effective intelligence.
What’s Happening Now?: Uranium
Smuggling: How Do We Stop It?
• U.S. outfits border crossing stations in
former Soviet bloc countries.
• Several agencies are involved
» DOE: Second Line of Defense Program (SLOD)
» DHS
» Department of State
• 39 sites
• 200 attempts uncovered in 2004, yet breaches are
still possible.
What’s Happening Now?: Uranium
Smuggling: How Do We Stop It?
• In 2003, DOE (SLOD/Mega Ports
Initiative): Ports all over the world receive
x-ray scanners and ultra-sensitive
radiation detectors.
• Detection Techniques – active
• X-ray imaging exposes lead enclosures
• Detection Techniques – passive
• Gamma ray and neutron imaging induce a small
amount of fusion
What’s Happening Now?: Uranium
Smuggling: How Do We Stop It?
• Once detected, a suspicious container can
be searched by inspectors with belt-worn
radiation pagers.
• Smugglers could carry sources for a dirty
bomb, a dispersant driven by a
conventional weapon that disperses
radioactive material such as Cs137, or Sr90.
• These had been scavenged from radio-isotope
thermal generators left in the wilds of the former
Soviet Union.
What’s Happening Now?: Uranium
Smuggling: How Do We Stop It?
• Sources are detected and categorized by
their spectra (counts versus energy, in
Kev)
• These material are efficient, but not foolproof.
What’s Happening Now?: Uranium
Smuggling: Weaknesses in the System
• If sufficiently determined terrorists are able
to elude detection, it will bee in a manner
that we cannot expect. Our methods are a
deterrent, but are not foolproof.
• Fissionable materials from a nuclear
weapon, yet not feasible for dirty bombs
would be hard to detect.
What’s Happening Now?: Uranium
Smuggling: Weaknesses in the System
• Smugglers could place shielding around
nuclear materials or attempt to disquise
them with normally radioactive materials,
or “interference cargo”. These include:
•
•
•
•
•
Fertilizer
Kitty litter
Television sets
Granite slabs
Road Salt
• Smoke
Detectors
•Glazed ceramics
•Medical Isotopes
What’s Happening Now?: Uranium
Smuggling: Weaknesses in the System
• “If we are successful in doing so for long
enough … these efforts will have been of
great benefit to the nation”
Kouzes Amer. Scientist (2005)