Nuclear-weapons design and testing
China's nuclear arsenal has long been an enigma. It is a small force, based almost exclusively on land-based ballistic missiles, maintained at a low level of alert and married to a no-first-use doctrine – all choices that would seem to invite attack in a crisis. Chinese leaders, when they have spoken about nuclear weapons, have articulated ideas that sound odd to the Western ear. Mao Zedong's oft-quoted remark that ‘nuclear weapons are a paper tiger’ seems to be bluster or madness. China's nuclear forces are now too important to remain a mystery. Yet Westerners continue to disagree about basic factual information concerning one of the world's most important nuclear-weapons states. This Adelphi book documents and explains the evolution of China's nuclear forces in terms of historical, bureaucratic and ideological factors. There is a strategic logic at work, but that logic is mediated through politics, bureaucracy and ideology. The simplest explanation is that Chinese leaders, taken as a whole, have tended to place relatively little emphasis on the sort of technical details that dominated US discussions regarding deterrence. Such profound differences in thinking about nuclear weapons could lead to catastrophic misunderstanding in the event of a military crisis between Beijing and Washington.
A Convenient Spy: Wen Ho Lee and the Politics of Nuclear Espionage
No espionage case in recent decades has been anything like the Wen Ho Lee affair. As Dan Stober and Ian Hoffman describe in "A Convenient Spy," an astonishingly inept investigation of a crime that may never have occurred ended in a national disgrace. A weapons-code scientist at Los Alamos National Laboratory, Lee was hunted as a spy for China, indicted on fifty-nine counts, and held in detention for nine months as a threat to the entire nation. But after pleading guilty to just one count, he went home -- with an unusual and emotional apology from a federal judge. Prosecutors' claims that Lee had stolen America's "crown jewels" of nuclear security simply evaporated. Yet Lee's motives have never been satisfactorily explained, and his often-repeated excuse that he was just backing up his work files does not stand up to scrutiny. As Stober and Hoffman report, Lee's lies and his unexplained connections to foreign scientists spanned eighteen years. He was a security nightmare. Tapping at his keyboard, he assembled a private collection of the computer programs used to design America's nuclear weapons, then left them vulnerable to hackers and foreign intelligence services for years. The FBI's belated discovery that he had also put the codes on portable cassette tapes launched a frenzied worldwide search that eventually carried agents to the Los Alamos landfill. And yet today, the tapes have never been found. In 1995, Lee was just another American, a Taiwanese immigrant striving to support a family he cherished and to make a name for himself in scientific circles. Unknown to him, however, scientists working in the secret world of nuclear-weapons intelligence examined purloinedChinese documents, studied spy reports, and wondered: Had China stolen the secrets of the W88, America's most advanced nuclear weapon? Scientific hunches rapidly evolved into a criminal investigation aimed at Lee. He had been overheard by the FBI while telephoning a spy suspect, and he was warmly embraced by a high-ranking Chinese nuclear-weapons official whom he wasn't supposed to know. The FBI noted that he was "ethnic Chinese." And in this uncertain period after the Cold War, many politicians played up China as a threatening new enemy. Energy Secretary and vice presidential hopeful Bill Richardson was eager to fire Lee and appear decisive in protecting national security. In this stormy confluence of intelligence and politics, Lee became a convenient spy. But was he guilty? Dan Stober and Ian Hoffman tell the story of the Wen Ho Lee fiasco dramatically and authoritatively, providing an objective account that no partisan version of the story can match.
An Evaluation of Seismic Decoupling and Underground Nuclear Test Monitoring Using High-Frequency Seismic Data (Paper 5R0913)
An effective solution to the problem of the detection and identification of low-yield coupled and fully decoupled underground nuclear explosions appears available via use of high-frequency seismic data ranging up to 30 or 40 Hz. In order to evaluate detection-identification capabilities when using such data, it is necessary to estimate (1) spectral characteristics and relative amplitudes of both P and S waves from explosions and earthquakes over the frequency band from 5 to 40 Hz, (2) signal transmission characteristics over this band through pertinent types of earth structure, and (3) recording system and ground noise characteristics over this frequency band. In this study, each of these topics is considered in turn as they relate to detection and discrimination of the signals from low-yield coupled and decoupled explosions in the regional and teleseismic distance ranges. Estimates of the capabilities of specific hypothetical networks to detect and identify (insofar as signal-to-noise ratio is an important factor in identification) explosions within the USSR are then considered. These estimates of signal detection capability provide the central focus for the study as they serve to translate diverse and rather complex sets of observational data and theory into concrete predictions of monitoring capability. Following the assessment of detection capabilities, the problem of identification of small events is considered, with particular emphasis on discrimination at regional distances where the network is calculated to provide signals of high signal-to-noise ratio. The principal results and conclusions of this study are as follows: (1) seismic system noise can be suppressed to levels well below ground noise at quiet sites up to frequencies at least as high as 30–40 Hz when using presently available hardware; (2) average amplitudes of high-frequency noise in a variety of geological environments are very low and change little with time or season; (3) transmission of high-frequency P and S wave signals in the regional distance range in stable continental areas and shields is nearly as efficient as at 1 Hz, with effective Q factors in shield areas being about 9000 and 4000 for high-frequency Pn and Sn, respectively, while the effective Q for Pn waves in tectonic areas is about 1000; (4) a properly designed and deployed network of 25 simple three-component nonarray stations internal to the USSR and 15 similar stations surrounding the USSR is predicted to be capable of multistation detection at high signal-to-noise ratio of fully decoupled 1-kt explosions located at all potential decoupling sites within the USSR; (5) by inference from the quantitative agreement of empirical observations and theoretical predictions, when using lower-frequency data over a great range of explosion yields, we conclude that procedures based on the use of both detectable P and S waves will serve to identify explosion-generated seismic signals at least as small as those expected from a fully decoupled 1-kt explosion.