A neutron bomb, or enhanced radiation weapon (ERW), is a type of nuclear weapon designed specifically to release a large portion of its energy as energetic neutron radiation rather than explosive energy. Although their extreme blast and heat effects are not eliminated, it is the enormous radiation released by ERWs that is meant to be a major source of casualties. The levels of neutron radiation released are able to penetrate, in certain cases, through thicker materials than explosive energy can.
The term enhanced radiation refers only to the burst of neutron radiation released at the moment of detonation, not to any enhancement of residual radiation in fallout as in the theoretical case of a cobalt bomb.
The "usual" nuclear weapon yield—expressed as kT TNT equivalent—is not a measure of a neutron weapon's destructive power. It refers only to the energy released (mostly heat and blast), and does not express the lethal effect of neutron radiation on living organisms. Compared to a fission bomb with the identical explosive yield, a neutron bomb would emit about ten times[1] the amount of neutron radiation. In a fission bomb, radiation pulse energy is approximately 5% of entire energy released; in the neutron bomb it would be closer to 50%.
Three types of ERW were built by the United States.[6] The W66 warhead, for the anti-ICBM Sprint missile system, was deployed in 1975 and retired the next year, along with the missile system. The W70 Mod 3 warhead was developed for the short-range, tactical Lance missile, and the W79 Mod 0 was developed for artillery shells. The latter two types were retired by President George H. W. Bush in 1992, following the end of the Cold War.[7][8] The last W70 Mod 3 warhead was dismantled in 1996,[9] and the last W79 Mod 0 was dismantled by 2003, when the dismantling of all W79 variants was completed.[10]
Besides the United States and Soviet Union, France and China are understood to have tested neutron or enhanced radiation bombs in the past, with France apparently leading the field with an early test of the technology in 1967[11] and an "actual" neutron bomb in 1980.[12] The 1999 Cox Report indicates that China is able to produce neutron bombs,[13] although no country is currently known to deploy them.
Neutron bombs could be used as strategic anti-ballistic missile weapons or as tactical weapons intended for use against armored forces; in fact, the US neutron bomb was originally conceived as a weapon that could stop Soviet armored divisions from overrunning Western Europe without[citation needed] destroying Western Europe in the process. In the late 1970s, Leonid Brezhnev described the neutron bomb as the ultimate capitalist bomb[15], because it destroyed people not property.[citation needed]
ER weapons are meant to kill a much higher percentage of enemy personnel inside such protected environments through the release of a higher percentage of their yield in the form of neutron ionizing radiation, against which even tank armor is not very effective.
The effective range of a nuclear weapon against tanks is determined by the lethal range of the radiation, although this is also reduced by the armor. By emitting large amounts of lethal radiation of one of the most penetrating kinds, ER warheads maximize the lethal range of a nuclear warhead against armored targets, while keeping low explosive yield. At the same time, modest fallout shelters of ordinary design would presumably protect civilian populations.
A radiation dose of 6 Sv is normally considered lethal. It will kill at least half of those who are exposed to it in a matter of weeks, but no effect is noticeable for several hours.
Many of those hit with 10-50 Sv of radiation, although their eventual death is certain, will initially experience only a brief bout of nausea followed by a temporary recovery (the latent, or "walking ghost", phase[16]) lasting hours to days. In this time, affected armored units are capable of considerable advancement into the enemy territory, so their immediate military value does not decrease much.
For a dose above 50 Sv, immediate disorientation is experienced and death within 48 hours. A dose that quickly kills humans is estimated at ca. 800 Sv.[17]
Contents[hide] |
[edit] Detailed description
An ERW is a fission-fusion thermonuclear weapon (hydrogen bomb) in which the burst of neutrons generated by a fusion reaction is intentionally allowed to escape the weapon, rather than being absorbed by its other components. The weapon's X-ray mirrors and radiation case, made of uranium or lead in a standard bomb, are instead made of chromium or nickel so that the neutrons can escape.The term enhanced radiation refers only to the burst of neutron radiation released at the moment of detonation, not to any enhancement of residual radiation in fallout as in the theoretical case of a cobalt bomb.
The "usual" nuclear weapon yield—expressed as kT TNT equivalent—is not a measure of a neutron weapon's destructive power. It refers only to the energy released (mostly heat and blast), and does not express the lethal effect of neutron radiation on living organisms. Compared to a fission bomb with the identical explosive yield, a neutron bomb would emit about ten times[1] the amount of neutron radiation. In a fission bomb, radiation pulse energy is approximately 5% of entire energy released; in the neutron bomb it would be closer to 50%.
[edit] Long-term storage problem
A neutron bomb requires considerable amounts of tritium, which has a half-life of approximately 12.32 years,[2] compounding the difficulties of extended storage. For a weapon to remain effective over time, tritium components would have to be periodically replaced.[edit] History
Conception of the neutron bomb is generally credited to Samuel T. Cohen of the Lawrence Livermore National Laboratory, who developed the concept in 1958.[3] Testing was authorized and carried out in 1963 at an underground Nevada test facility.[4] Development was subsequently postponed by President Jimmy Carter in 1978 following protests against his administration's plans to deploy neutron warheads in Europe. President Ronald Reagan restarted production in 1981.[5]Three types of ERW were built by the United States.[6] The W66 warhead, for the anti-ICBM Sprint missile system, was deployed in 1975 and retired the next year, along with the missile system. The W70 Mod 3 warhead was developed for the short-range, tactical Lance missile, and the W79 Mod 0 was developed for artillery shells. The latter two types were retired by President George H. W. Bush in 1992, following the end of the Cold War.[7][8] The last W70 Mod 3 warhead was dismantled in 1996,[9] and the last W79 Mod 0 was dismantled by 2003, when the dismantling of all W79 variants was completed.[10]
Besides the United States and Soviet Union, France and China are understood to have tested neutron or enhanced radiation bombs in the past, with France apparently leading the field with an early test of the technology in 1967[11] and an "actual" neutron bomb in 1980.[12] The 1999 Cox Report indicates that China is able to produce neutron bombs,[13] although no country is currently known to deploy them.
[edit] Use of neutron bomb
Neutron bombs are purposely designed with explosive yields lower than other nuclear weapons.[citation needed] This is because neutrons are absorbed by air, so a high-yield neutron bomb is not able to radiate neutrons beyond its blast range and so would have no destructive advantage over a normal hydrogen bomb. This intense pulse of high-energy neutrons is intended as the principal killing mechanism, not the fallout, heat or blast. Although neutron bombs are commonly believed to "leave the infrastructure intact", current designs have explosive yields in the kiloton range,[14] the detonation of which would cause considerable destruction through blast and heat effects.Neutron bombs could be used as strategic anti-ballistic missile weapons or as tactical weapons intended for use against armored forces; in fact, the US neutron bomb was originally conceived as a weapon that could stop Soviet armored divisions from overrunning Western Europe without[citation needed] destroying Western Europe in the process. In the late 1970s, Leonid Brezhnev described the neutron bomb as the ultimate capitalist bomb[15], because it destroyed people not property.[citation needed]
[edit] Use against armor
One of the uses for which this weapon was conceived is large-scale anti-tank weaponry. Armored fighting vehicles offer a relatively high degree of protection against heat and blast, the primary destructive mechanisms of normal nuclear weapons. That is, military personnel inside a tank can be expected to survive an "ordinary" nuclear explosion at relatively close range, while the vehicle's Nuclear/Biological/Chemical protection systems ensure a high degree of operability even in a nuclear fallout environment.ER weapons are meant to kill a much higher percentage of enemy personnel inside such protected environments through the release of a higher percentage of their yield in the form of neutron ionizing radiation, against which even tank armor is not very effective.
The effective range of a nuclear weapon against tanks is determined by the lethal range of the radiation, although this is also reduced by the armor. By emitting large amounts of lethal radiation of one of the most penetrating kinds, ER warheads maximize the lethal range of a nuclear warhead against armored targets, while keeping low explosive yield. At the same time, modest fallout shelters of ordinary design would presumably protect civilian populations.
[edit] Secondary radioactivity
The neutron flux can induce significant amounts of short-lived secondary radioactivity in the environment near the burst point. The alloys used in steel armor can develop radioactivity that is dangerous for 24–48 hours.[edit] Operational difficulties
One problem with using radiation as a tactical anti-personnel weapon is a requirement of giant overdose. To have a meaningful military effect, a radiation dose has to be administered exceeding the lethal level many times.A radiation dose of 6 Sv is normally considered lethal. It will kill at least half of those who are exposed to it in a matter of weeks, but no effect is noticeable for several hours.
Many of those hit with 10-50 Sv of radiation, although their eventual death is certain, will initially experience only a brief bout of nausea followed by a temporary recovery (the latent, or "walking ghost", phase[16]) lasting hours to days. In this time, affected armored units are capable of considerable advancement into the enemy territory, so their immediate military value does not decrease much.
For a dose above 50 Sv, immediate disorientation is experienced and death within 48 hours. A dose that quickly kills humans is estimated at ca. 800 Sv.[17]
[edit] Use against ballistic missiles
As an anti-ballistic missile weapon, an ER warhead was developed for the Sprint missile system as part of the Safeguard Program to protect United States cities and missile silos from incoming Soviet warheads by damaging their electronic components with the intense neutron flux.[edit] See also
[edit] References
- ^ Kistiakovsky, George (Sep 1978). "The folly of the neutron bomb". Bulletin of the Atomic Scientists 34: 27. Retrieved 11 February 2011.
- ^ Comprehensive Review and Critical Evaluation of the Half-Life of Tritium, National Institute of Standards and Technology
- ^ Robert D. McFadden (December 1, 2010). "Samuel T. Cohen, Neutron Bomb Inventor, Dies at 89". New York Times. Retrieved 2010-12-02. "After the war, he joined the RAND Corporation and in 1958 designed the neutron bomb as a way to strike a cluster of enemy forces while sparing infrastructure and distant civilian populations."
- ^ "About: Chemistry article", by Anne Marie Helmenstine, Ph. D
- ^ "On this Day: 7 April". BBC. 1978-04-07. Retrieved 2010-07-02. "Jimmy Carter's successor, Ronald Reagan, changed US policy and gave the order for the production of neutron warheads to start in 1981. ..."
- ^ Nuclear Weapon News and Background
- ^ Christopher Ruddy (June 15, 1997). "Bomb inventor says U.S. defenses suffer because of politics". Tribune-Review. Retrieved 2010-07-03. "With the fall of the Berlin Wall and the end of communism as we knew it, the Bush administration moved to dismantle all of our tactical nuclear weapons, including the Reagan stockpile of neutron bombs. In Cohen's mind, America was brought back to Square One. Without tactical weapons like the neutron bomb, America would be left with two choices if an enemy was winning a conventional war: surrender, or unleash the holocaust of strategic nuclear weapons."
- ^ Types of Nuclear Weapons
- ^ March 13, 1996
- ^ National Nuclear Security Administration - Homepage
- ^ BBC News: Neutron bomb: Why 'clean' is deadly
- ^ UK parliamentary question on whether condemnation was considered by Thatcher government [1]
- ^ U.S. National Security and Military/Commercial Concerns with the People's Republic of China [2]
- ^ List of All U.S. Nuclear Weapons
- ^ National security for a new era: globalization and geopolitics after Iraq, Donald Snow
- ^ Nuclear Fact:Fallout, Jake Moilanen, NRE 301 final project.
- ^ First source says 8000 rad of fast neutron radiation, the second source explains it can be converted to 800 Sv by assuming Q=10: (1) Nuclear Fact:Fallout, (2) Measures Relative to the Biological Effect of Radiation Exposure.
[edit] Further reading
- Cohen, Sam, The Truth About the Neutron Bomb: The Inventor of the Bomb Speaks Out, William Morrow & Co., 1983, ISBN 0-688-01646-4
- Cohen, Sam, "Shame: Confessions of the Father of the Neutron Bomb", Xlibris Corporation, 2000, ISBN 0-7388-2230-2
[edit] External links
- Strategic Implications of Enhanced Radiation Weapons
- What is a neutron bomb?
- Nuclear Files.org Definition and history of the neutron bomb
