Radiological Warfare: Unseen Threats and Strategic Impacts of Nuclear Contamination

By Fouad Sabry

What is Radiological Warfare

Radiological warfare is any form of warfare involving deliberate radiation poisoning or contamination of an area with radiological sources.

How you will benefit

(I) Insights, and validations about the following topics:

Chapter 1: Radiological warfare

Chapter 2: Little Boy

Chapter 3: Nuclear weapon

Chapter 4: Nuclear fission

Chapter 5: Neutron bomb

Chapter 6: Nuclear fallout

Chapter 7: Dirty bomb

Chapter 8: Cobalt bomb

Chapter 9: Nuclear technology

Chapter 10: Nuclear weapon design

(II) Answering the public top questions about radiological warfare.

Who this book is for

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of Radiological Warfare.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: May 31, 2024

Book preview

Chapter 1: Radiological warfare

Radiological warfare is any form of warfare involving the intentional poisoning or pollution of a region with radioactive materials.

Typically, radioactive weapons are classified as weapons of mass destruction (WMDs), A salted bomb is a nuclear weapon containing a substantial amount of radiologically inert salting material. The radiological warfare agents are formed by the neutron capture of the nuclear weapon's neutron radiation by the salting materials. This eliminates the need to store highly radioactive material, as it is produced by the bomb's explosion. The resulting fallout is more intense than that of conventional nuclear weapons and can render a region uninhabitable for an extended length of time.

Neutron capture converts cobalt-59 to cobalt-60 in the cobalt bomb, which is an example of a radiological warfare weapon. Initially, the gamma radiation of nuclear fission products from an equivalently sized clean fission-fusion-fission bomb is significantly more intense than cobalt-60: 15,000 times more intense at 1 hour, 35 times more intense at 1 week, 5 times more intense at 1 month, and almost equal at 6 months. The cobalt-60 fallout is eight times more intense than fission after one year and one hundred fifty times more intense after five years. After around 75 years, the extremely long-lived isotopes created by fission would once again surpass cobalt-60.

If the effects of thermal radiation and blast wave need to be maximized for an area, an air burst is chosen (i.e. formation of mach stem, and not shielded by terrain). Neutron radiation from both fission and fusion weapons will irradiate the detonation site, triggering neutron activation of the material there. Additionally, fission bombs will contribute to the bomb residue. Neutron activation of air will not produce isotopes relevant for radiological warfare. By detonating them at or near the surface, the ground will be evaporated, become radioactive, and generate substantial fallout as it cools and condenses into particles.

A dirty bomb or radiological dispersal device, whose objective is to distribute radioactive dust across an area, is a radiological weapon of much lower technology than those previously mentioned. The release of radioactive material may not involve a unique weapon or side effects like a blast explosion and may not directly kill people from its radiation source, but it might render entire areas or structures inhospitable to human life. Radioactive material may be slowly disseminated over a vast region, making it difficult for victims to initially recognize a radiological attack, especially if radioactivity detectors have not been set beforehand.

{End Chapter 1}

Chapter 2: Little Boy

Little Boy was the name of the atomic bomb used to destroy the Japanese city of Hiroshima on August 6, 1945, during World War II. It was the first nuclear weapon ever used in combat. The bomb was dropped by Colonel Paul W. Tibbets Jr., commander of the 509th Composite Group, and Captain Robert A. Lewis, pilots of the Boeing B-29 Superfortress Enola Gay. It exploded with the force of approximately 15 kilotons of TNT (63 TJ), causing significant destruction and fatalities throughout the city. The Hiroshima bombing was the second nuclear explosion caused by humans in history, following the Trinity nuclear test.

During World War II, Lieutenant Commander Francis Birch's team at the Manhattan Project's Los Alamos Laboratory redesigned their abandoned Thin Man nuclear bomb into Little Boy. It was a gun-type fission weapon, similar to Thin Man, but its explosive force was obtained from the nuclear fission of uranium-235, whereas Thin Man was based on plutonium-239. Fission was achieved by propelling a hollow cylinder (the bullet) with nitrocellulose propellant powder at a solid cylinder of the same material (the target). It had 64 kilograms (141 pounds) of highly enriched uranium, although less than one kilogram experienced nuclear fission. Its components were manufactured at three separate facilities so that no one would have a copy of the entire design. In contrast to the implosion design, which required complex coordination of shaped explosive charges, the gun-type design was believed so likely to function that it was never tested before its initial deployment at Hiroshima.

After the end of the war, it was not anticipated that the ineffective Little Boy design would be used again, thus numerous drawings and designs were destroyed. Midway through 1946, the Hanford Site reactors began to suffer from the Wigner effect, the dislocation of atoms in a solid induced by neutron radiation, and plutonium became scarce; thus, Sandia Base manufactured six Little Boy assemblies. In 1947, the Navy Bureau of Ordnance produced an additional 25 Little Boy assemblies for use by the Lockheed P2V Neptune nuclear strike aircraft, which could be launched from aircraft carriers of the Midway-class. All Little Boy units were decommissioned at the end of January 1951.

During World War II, physicist Robert Serber dubbed the first two atomic bomb prototypes based on their shapes: Thin Man and Fat Man. The Thin Man was a long, thin device whose name was derived from the Dashiell Hammett novel and film series of the same name. It was named after Kasper Gutman, a corpulent character in Dashiell Hammett's 1930 novel The Maltese Falcon, portrayed by Sydney Greenstreet in the 1941 film adaptation. Little Boy was given the name Thin Man by others as a reference to its design.

Since it was recognized that uranium-235 was fissionable, it was the first material pursued in the construction of the bomb. As the first design created (and the first to see battle), it is sometimes referred to as the Mark I.

Little Boy was a condensed version of Thin Man, The earlier design for gun-type fission weapons.

Thin Man, 17 foot (5.2 m) in length, intended to use plutonium, Therefore, it was also capable of employing enriched uranium.

After Emilio G.'s research, the Thin Man concept was abandoned.

Segrè and his P-5 Group at Los Alamos on the newly reactor-produced plutonium from Oak Ridge and the Hanford site showed that it contained impurities in the form of the isotope plutonium-240.

This has a significantly higher spontaneous fission rate and radioactivity than the cyclotron-produced plutonium used for the original observations, Moreover, its incorporation into reactor-produced plutonium (necessary for bomb production due to required amounts) appeared inevitable.

This indicated that the background fission rate of the plutonium was so high that it was extremely probable that the plutonium would self-detonate and explode upon the formation of a critical mass.

The Little Boy measured 120 inches (300 cm) in length, had a diameter of 28 inches (71 cm), and weighed around 4,500 kg (4,400 kg).

Following the gun principle, the uranium-235 inside the weapon was separated into two parts: the projectile and the target. The projectile was a hollow cylinder that accounted for sixty percent of its overall mass (38.5 kg [85 lb]). It consisted of a stack of nine uranium rings, each 6.25 inches (159 mm) in diameter with a 4-inch (100 mm) bore in the center and a total length of 7 inches (180 mm), pressed into the front end of a 16.25-inch (413-mm) long thin-walled projectile. Behind these rings, the remaining space in the projectile was filled by a tungsten carbide disc with a steel rear. The projectile slug was propelled 42 inches (1,100 mm) along the 72-inch (1,800 mm) long, 6.5-inch (170 mm) wide smooth-bore gun barrel upon ignition. The insert for the slug was a 7-inch long, 4-inch diameter cylinder with a 1-inch (25 mm) axial hole. The projectile represented forty percent of the entire fissile mass (25.6 kg or 56 lb). The insert consisted of a stack of six washer-like uranium discs that were somewhat thicker than the projectile rings and slid over a 1-inch rod. This rod then protruded from the front of the bomb case after passing through the tungsten carbide tamper plug, impact-absorbing anvil, and nose plug backstop. This entire target assembly was secured with locknuts at both ends.

Every published description and illustration of the Little Boy mechanism for the first fifty years after 1945 thought that a small, solid bullet was shot into the middle of a bigger, stationary target. In Little Boy, however, critical mass considerations dictated that the larger, hollow piece would be the projectile. The built fissile core had uranium-235 in excess of two critical masses. This necessitated that one of the two components have a critical mass greater than one, with the bigger component avoiding criticality prior to assembly through form and little contact with the neutron-reflecting tungsten carbide tamper.

A hole in the center of the bigger piece scattered the mass and increased the surface area, allowing more fission neutrons to escape and so avoiding a chain reaction from occurring prematurely.

The fuzing device was meant to activate at the most devastating altitude, 580 meters according to calculations (1,900 ft). It utilized a three-level interlocking mechanism:

To safeguard the safety of the aircraft, a timer prevented the bomb from detonating until at least fifteen seconds after release, or one-fourth of the projected fall time. The timer was activated when the electrical pull-out plugs connecting it to the aircraft detached as the bomb detonated, switching it to its internal 24-volt battery and commencing the timer. At the end of 15 seconds, the bomb would be 3,600 feet (1,100 m) away from the aircraft, at which point the radar altimeters were activated and control was transferred to the barometric stage.

The barometer stage served to delay activation of the radar altimeter firing command circuit until approaching explosion altitude. As ambient air pressure increased during descent, a thin metallic membrane covering a vacuum chamber distorted gradually (a similar construction is still in use today in antique wall barometers). The barometric fuze was deemed insufficiently precise to detonate the bomb at the proper ignition height since local air pressure varied. When the bomb reached the intended height for this stage (reportedly 2,000 meters; 6,561.6 feet), the membrane closed a circuit and activated the radar altimeters. The barometer stage was introduced out of concern that external radar signals could prematurely ignite the bomb.

Multiple redundant radar altimeters were utilized to accurately determine the final altitude. When the altimeters detected the proper height, the firing switch closed, igniting the three BuOrd Mk15, Mod 1 Navy gun primers in the breech plug and detonating the charge consisting of four silk powder bags, each holding 2 pounds (0.9 kilograms) of WM slotted-tube cordite. This caused the uranium bullet to be propelled toward the opposite end of the gun barrel at a muzzle velocity of 300 meters per second (980 feet per second). The chain reaction began approximately 10 milliseconds later and lasted less than 1 microsecond. The radar altimeters were modified U.S. Army Air Corps APS-13 tail warning radars, often known as Archie, which are typically used to warn a fighter pilot of an oncoming aircraft from behind.

The designations for the Little Boy pre-assemblies were L-1, L-2, L-3, L-4, L-5, L-6, L-7, and L-11. In test drops, L-1, L-2, L-5, and L-6 were consumed. On July 23, 1945, the first drop test was conducted with L-1. Colonel Paul W. Tibbets, commander of the 509th Composite Group, dropped it over the ocean near Tinian in order to test the radar altimeter aboard the B-29 subsequently dubbed Big Stink. On July 24 and 25, the L-2 and L-5 units were used to conduct two further drop tests over the ocean in order to test all components. Both missions were piloted by Tibbets, but this time the bomber was the one that became known as Jabit. On July 29, L-6 was used as a dress rehearsal. Major Charles W. Sweeney flew the B-29 Next Objective to Iwo Jima, where emergency procedures for loading the bomb onto a reserve aircraft were performed. On July 31, this drill was repeated, but this time L-6 was reloaded onto a different B-29, Enola Gay, piloted by Tibbets, and a test