W88

The W88 is a United States thermonuclear warhead, with an estimated yield of 475 kiloton (kt), and is small enough to fit on MIRVed missiles. The W88 was designed at the Los Alamos National Laboratory in the 1970s. In 1999 the director of Los Alamos who had presided over its design described it as "the most advanced U.S. nuclear warhead." [Harold M. Agnew, "Letter: Looking for Spies in Nuclear Kitchen", "Wall Street Journal" (17 May 1999), p. A27. [http://www.fas.org/irp/ops/ci/agnewwsj.html] ]

The Trident II SLBM can be armed with up to 8 W88 (475 kt) warheads (Mark 5) or 8 W76 (100 kt) warheads (Mark 4), but it is limited to 4 warheads under SORT.

Design revelations

Information about the W88 has implied that it is a variation of the standard Teller-Ulam design for thermonuclear weapons.

In 1999, a reporter for the "San Jose Mercury News" reported that the U.S. W88 nuclear warhead, a small MIRVed warhead used on the Trident II SLBM, had a prolate (egg- or watermelon-shaped) "primary" (code-named "Komodo") and a spherical "secondary" (code-named "Cursa") inside a specially-shaped radiation case (known as the "peanut" for its shape). A story four months later in "The New York Times" by William Broad reported that in 1995, a supposed double agent from the People's Republic of China delivered information indicating that China knew these details about the W88 warhead as well, supposedly through espionage (this line of investigation eventually resulted in the abortive trial of Wen Ho Lee). If these stories are true, it would indicate a variation of the Teller-Ulam design which would allow for the miniaturization required for small MIRVed warheads. [Dan Stober and Ian Hoffman, "A convenient spy: Wen Ho Lee and the politics of nuclear espionage" (New York: Simon & Schuster, 2001). ISBN 0-7432-2378-0] [Howard Morland, "The holocaust bomb: A question of time" (February 2003) [http://www.fas.org/sgp/eprint/morland.html] ] [William J. Broad, "Spies versus sweat, the debate over China's nuclear advance," "New York Times" (7 September 1999), p. 1.]

The value of a prolate "primary" lies apparently in the fact that a MIRV warhead is limited by the diameter of the "primary" — if a prolate "primary" can be made to work properly, then the MIRV warhead can be made considerably smaller yet still deliver a high-yield explosion — a W88 warhead manages to yield up 475 kt with a physics package 68.9 in (1.75 m) long, with a maximum diameter of 21.8 in (0.55 m), and weighing probably less than 800 lb (360 kg). [ [http://nuclearweaponarchive.org/Usa/Weapons/W88.html Nuclear Weapon Archive] ] Smaller warheads can allow a nation to fit more of them onto a single missile, as well as improve in more basic flight properties such as speed, mileage, and range.

The calculations for a nonspherical "primary" are apparently orders of magnitude harder than for a spherical "primary" (a spherically symmetric simulation is one dimensional, while an axially symmetric simulation is two dimensional; simulations typically divide up each dimension into discrete segments, so a one dimensional simulation might involve only 100 points, while a similarly accurate two dimensional simulation would require 10,000), which would likely be the reason they would be desirable for a country like the People's Republic of China (which already developed its own nuclear and thermonuclear weapons), especially since they were no longer conducting nuclear testing which would provide valuable design information. [Christopher Cox, chairman, "Report of the United States House of Representatives Select Committee on U.S. National Security and Military/Commercial Concerns with the People's Republic of China" (1999), esp. Ch. 2, "PRC Theft of U.S. Thermonuclear Warhead Design Information". [http://www.house.gov/coxreport/] ]

ee also

*List of nuclear weapons

References

External links

* [http://nuclearweaponarchive.org/Usa/Weapons/W88.html Nuclear weapons archive on the W88]
* [http://www.globalsecurity.org/wmd/systems/w88.htm Globalsecurity.org on the W88]
* [http://www.senate.gov/~gov_affairs/080599_china_espionage_statement.htm "Department of Energy, FBI, and Department of Justice Handling of the Espionage Investigation into the Compromise of Design Information on the W-88 Warhead"] statement by U.S. Senate Governmental Affairs Committee heads.