ISSN:0031-9228    

DOI:10.1063/1.2807827

出版商:AIP    

年代:1996

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.881601

出版商:AIP    

年代:1996

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.881557

出版商:AIP    

年代:1996

数据来源: AIP

摘要:

There aren't many hydroxyl molecules (OH) in the troposphere, but the few that are there certainly make their presence known. More than any other species in the troposphere (the atmospheric layer between Earth's surface and an altitude of 8–18 km), the OH radical determines the lifetimes of such common atmospheric constituents as carbon monoxide, methane and sulfur dioxide. Yet, because of its short atmospheric lifetime (a single molecule sticks around less than one second) and low concentrations (a few tenths of a part per trillion, compared, for example to carbon dioxide levels, which are a few hundred parts per million), the OH radical has defied accurate measurement. Not any more.

ISSN:0031-9228    

DOI:10.1063/1.881544

出版商:AIP    

年代:1996

数据来源: AIP

摘要:

The symmetrization postulate of quantum mechanics asserts that the multiparticle wavefunction for any collection of identical particles must be either wholly symmetric or wholly antisymmetric under the exchange of labels between any two particles. In nonrelativistic quantum mechanics, this postulate is a somewhatad hocassumption tacked onto the theory; wholly symmetric or antisymmetric wave functions are not the only ways of preserving the indistinguishability of identical particles.

ISSN:0031-9228    

DOI:10.1063/1.881531

出版商:AIP    

年代:1996

数据来源: AIP

摘要:

The proliferation in recent years of the number of techniques for studying surface magnetism is partly attributable to the increasing importance of surface magnetism in the multibillion‐dollar recording industry—in the design of ultrahigh‐density storage devices and possible applications of giant and colossal magneto resistance in metallic thin film multilayers, for example. To many physicists, however, surface magnetism has a more fundamental importance: Bulk magnetism is the quintessential example of long‐range ordering, and crystalline symmetry—on which theories of bulk magnetism depend—is broken at the surface. As such, surface magnetism provides physicists with an opportunity to investigate the mechanisms of magnetic ordering between the well‐understood limits of atomic and bulk‐matter magnetism.

ISSN:0031-9228    

DOI:10.1063/1.881545

出版商:AIP    

年代:1996

数据来源: AIP

摘要:

Nuclear history has opened up remarkably since the end of the cold war and the collapse of the Soviet Union. The Soviet nuclear program and the history of the US‐Soviet nuclear arms race can now be studied in quite a new way, thanks to information from Russian archives and from participants in the program itself.

ISSN:0031-9228    

DOI:10.1063/1.881526

出版商:AIP    

年代:1996

数据来源: AIP

摘要:

In feudal times, society was viewed as being made up of three estates, a “trinity,” functioning under the king's beneficence: the Lords Spiritual, the Lords Temporal and the Peasants. For all of its modern aspirations, Stalin's Soviet society of the 1940s and '50s was, in fact, feudal. Certainly that was true of the nuclear community. The respect reserved for the clergy in feudal times went to the security services. The nuclear nobility, the designers, lived well and were accorded full honors. And then there were those who did the tough and dirty work, the peasants. Some were recent graduates in chemistry or physics; no one was concerned by the serious overdoses of radiation that many received. Others were engineers, pursuing one blind alley after another with no time for the ordered exploration of alternatives. Still others were prisoners and soldiers, building the foundations and infrastructure that supported the program. They all were “peasants” in this scheme of things.

ISSN:0031-9228    

DOI:10.1063/1.881546

出版商:AIP    

年代:1996

数据来源: AIP

摘要:

In April 1947, a former Wall Street banker. Admiral Lewis Strauss, became a member of the newly established Atomic Energy Commission. At the time, both General Leslie Groves and J. Robert Oppenheimer believed that the Soviets were still a decade away from nuclear success; Naval Intelligence estimated the earliest date for a Soviet nuclear weapon as 1952, five years hence. Nevertheless, just one week after Strauss's appointment, he asked Secretary of Defense James E. Forrestal if any measures had been taken for the long‐range detection (LRD) of a hypothetical Soviet atomic bomb test, and the one‐time banker was surprised by the answer: No. Although he had little scientific knowledge of atomic weapons effects, Strauss felt intuitively that the military could and should have such a detection capability. He therefore pressed his deep concern to the military. The Office of Naval Research responded immediately.

ISSN:0031-9228    

DOI:10.1063/1.881547

出版商:AIP    

年代:1996

数据来源: AIP

摘要:

The creation of atomic weapons, and later thermonuclear weapons, was an event of such epochal significance in the 20th century that its history has preoccupied scientists worldwide and the international community at large. Those who have participated directly in nuclear weapons programs do not, and cannot, remain aloof from revealing the facts of that history. Of special interest is the early history of thermonuclear weapons development in the US and the USSR, the first countries to detonate this most dreadful species of nuclear weapon. In these three articles I present a brief survey and analysis of the principal events that make up that early history.

ISSN:0031-9228    

DOI:10.1063/1.881548

出版商:AIP    

年代:1996

数据来源: AIP