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Extragalactic origin of gamma-ray bursts. Revision 1

Description: Detectors of gamma-rays carried by satellites and later by high-flying balloons showed the existence of events lasting from fifteen milliseconds to about a hundred seconds, arriving from all directions in space. A few hundred events have been observed in a little more than a decade. The energy of gamma-rays range from a few kilovolts to millions of volts. Recent evidence indicates that considerable energy may be carried at least in some cases even above 10 MeV. But the bulk of the energy appeared to be emitted between 100 and 200 keV. The observed intensities range between 10/sup -3/ and 10/sup -7/ ergs/cm/sup 2/. The simple facts about intensity distribution are compatible with two extreme assumptions but exclude intermediate hypotheses. Either the events occur in our own galaxy in a region smaller than the thickness of the galaxy or they are of extragalactic origin and come from distant galaxies. Practically all attempted explanations have made the former explanation which requires that a mass of approximately 10/sup 20/ grams impinges on a neutron star (assuming a near to 100% conversion of gravitational energy available on the surface of the neutron star or 10/sup 20/ ergs/gram into gamma-rays which, of course, is unrealistic). In case of an extragalactic origin, the neutron star must attract and convert, as we shall see, about 2 x 10/sup 30/ grams or 10/sup -3/ of the solar mass. It is perhaps the size of such events which deterred a detailed discussion of this alternative. Montgomery Johnson and I have tried to assume these big collisions, explore the consequences, and I shall talk about this extragalactic hypothesis.
Date: November 2, 1984
Creator: Johnson, M. & Teller, E.
Partner: UNT Libraries Government Documents Department

On the extragalactic origin of gamma-ray bursts

Description: A theory to explain the origin of extragalactic gamma ray bursts is presented. Collisions of black dwarf and neutron stars with a subsequent fragmentation of the dwarf producing relativistic particle accelerations toward the neutron star and a resulting turbulent flow of material at the neutron star surface is postulated. (DWL)
Date: November 2, 1984
Creator: Johnson, M. & Teller, E.
Partner: UNT Libraries Government Documents Department

Peaceful uses of fusion

Description: Applications a thermonuclear energy for peaceful and constructive purposes are surveyed. Developments and problems in the release and control of fusion energy are reviewed. It is pointed out that the future of thermonuclear power reactors will depend upon the construction of a machine that produces more electric energy than it consumes. The fuel for thermonuclear reactors is cheap and practically inexhaustible. Thermonuclear reactors produce less dangerous radioactive materials than fission reactors and when once brought under control are not as likely to be subject to dangerous excursions. The interaction of the hot plasma with magnetic fields opens the way for the direct production of electricity. It is possible that explosive fusion energy released underground may be harnessed for the production of electricity before the same feat is accomplished in controlled fusion processes. Applications of underground detonations of fission devices in mining and for the enhancement of oil flow in large low--specific-yield formations are also suggested.
Date: July 1, 1958
Creator: Teller, E.
Partner: UNT Libraries Government Documents Department

Jahn-Teller effect: its history and applicability

Description: The interactions between Teller, Renner, Jahn and Landau which led to the formulation of the Jahn-Teller effect are discussed. The applicability of Jahn-Teller type of theory to superconductivity and the explanation proposed by the use of Goldstone particles are assessed.
Date: August 31, 1981
Creator: Teller, E.
Partner: UNT Libraries Government Documents Department

Nuclear energy for the third millennium

Description: The major energy sources of today are expected to last for only a small fraction of the millennium starting three years hence. In the plans of most people, nuclear energy has been ruled out for four separate reasons: 1. The danger of radioactivity from a reactor accident or from reactor products during a long period after reactor shutdown; 2. The proposed fuels, U-235 and also Pu-239, as obtained by presently available procedures will serve only for a limited duration; 3. Energy from nuclear reactors will be more expensive than costs of present alternatives; 4. The possibility of misusing the products for military purposes is an unacceptable danger. The development described below 1 attempts to meet all four objections. Specifically, we propose a structure as an example of future reactors that is deployed two hundred meters underground in loose and dry earth. The reactor is designed to function for thirty years, delivering electrical power on demand up to a level of thousand electrical megawatts. From the time that the reactor is started to the time of its shutdown thirty years later, the functioning is to be completely automatic. This is an obviously difficult condition to fulfill. The most important factor in making it possible is to design and operate the reactor without moving mechanical parts. At the start, the reactor functions on thermal neutrons within a structure containing uranium enriched in U-235 or having an addition of plutonium. That part of the reactor is to deliver energy for approximately one year after which a neighboring portion of the reactor containing thorium has been converted into Th-233 which rather rapidly decays into fissile U-233. This part of the assembly works on fission by fast neutrons. It will heat-up if insufficient thermal energy is withdrawn from the reactor`s core, under the negative feedback ...
Date: October 1, 1997
Creator: Teller, E.
Partner: UNT Libraries Government Documents Department

Global warming and ice ages: I. prospects for physics based modulation of global change

Description: It has been suggested that large-scale climate changes, mostly due to atmospheric injection of greenhouse gases connected with fossil-fired energy production, should be forestalled by internationally-agreed reductions in, e.g., electricity generation. The potential economic impacts of such limitations are obviously large: greater than or equal to $10{sup 11}/year. We propose that for far smaller - less than 1% - the mean thermal effects of greenhouse gases may be obviated in any of several distinct ways, some of them novel. These suggestions are all based on scatterers that prevent a small fraction of solar radiation from reaching all or part of the Earth. We propose research directed to quite near-term realization of one or more of these inexpensive approaches to cancel the effects of the greenhouse gas injection. While the magnitude of the climatic impact of greenhouse gases is currently uncertain, the prospect of severe failure of the climate, for instance at the onset of the next Ice Age, is undeniable. The proposals in this paper may lead to quite practical methods to reduce or eliminate all climate failures.
Date: August 15, 1996
Creator: Teller, E.; Wood, L. & Hyde, R.
Partner: UNT Libraries Government Documents Department

Completely automated nuclear reactors for long-term operation

Description: The authors discuss new types of nuclear fission reactors optimized for the generation of high-temperature heat for exceedingly safe, economic, and long-duration electricity production in large, long-lived central power stations. These reactors are quite different in design, implementation and operation from conventional light-water-cooled and -moderated reactors (LWRs) currently in widespread use, which were scaled-up from submarine nuclear propulsion reactors. They feature an inexpensive initial fuel loading which lasts the entire 30-year design life of the power-plant. The reactor contains a core comprised of a nuclear ignitor and a nuclear burn-wave propagating region comprised of natural thorium or uranium, a pressure shell for coolant transport purposes, and automatic emergency heat-dumping means to obviate concerns regarding loss-of-coolant accidents during the plant`s operational and post-operational life. These reactors are proposed to be situated in suitable environments at {approximately}100 meter depths underground, and their operation is completely automatic, with no moving parts and no human access during or after its operational lifetime, in order to avoid both error and misuse. The power plant`s heat engine and electrical generator subsystems are located above-ground.
Date: January 1, 1996
Creator: Teller, E.; Ishikawa, M. & Wood, L.
Partner: UNT Libraries Government Documents Department

Problem free nuclear power and global change

Description: Nuclear fission power reactors represent a solution-in-principle to all aspects of global change possibly induced by inputting of either particulate or carbon or sulfur oxides into the Earth`s atmosphere. Of proven technological feasibility, they presently produce high- grade heat for electricity generation, space heating and industrial process-driving around the world, without emitting greenhouse gases or atmospheric particulates. However, a substantial number of major issues currently stand between nuclear power implemented with light- water reactors and widespread substitution for large stationary fossil fuel-fired systems, including long-term fuel supply, adverse public perceptions regarding both long-term and acute operational safety, plant decommissioning, fuel reprocessing, radwaste disposal, fissile materials diversion to military purposes and - perhaps more seriously - cost. We describe a GW-scale, high-temperature nuclear reactor heat source that can operate with no human intervention for a few decades and that may be widely acceptable, since its safety features are simple, inexpensive and easily understood. We provide first-level details of a reactor system designed to satisfy these requirements. Such a back-solving approach to realizing large-scale nuclear fission power systems potentially leads to an energy source capable of meeting all large-scale stationary demands for high- temperature heat. If widely employed to support such demands, it could, for example, directly reduce present-day world-wide CO{sub 2} emissions by two-fold; by using it to produce non-carbonaceous fuels for small mobile demands, a second two-fold reduction could be attained. Even the first such reduction would permit continued slow power-demand growth in the First World and rapid development of the Third World, both without any governmental suppression of fossil fuel usage.
Date: August 15, 1997
Creator: Teller, E.; Wood, L.; Nuckolls, J.; Ishikawa, M. & Hyde, R.
Partner: UNT Libraries Government Documents Department

Cosmic bombardment V: Threat object-dispersing approaches to active planetary defense

Description: Earth-impacting comets and asteroids with diameters {approx}0.03 - 10 km pose the greatest threats to the terrestrial biosphere in terms of impact frequency-weighted impact consequences, and thus are of most concern to designers of active planetary defenses. Specific gravitational binding energies of such objects range from 10{sup -7} to 10{sup -2} J/gm, and are small compared with the specific energies of 1x10{sup 3} to 3x10{sup 3} J/gm required to vaporize objects of typical composition or the specific energies required to pulverize them, which are 10{sup -1} to 10 J/gm. All of these are small compared to the specific kinetic energy of these objects in the Earth- centered frame, which is 2x10{sup 5} to 2x10{sup 6} J/gm. The prospect naturally arises of negating all such threats by deflecting, pulverizing or vaporizing the objects. Pulverization-with-dispersal is an attractive option of reasonable defensive robustness. Examples of such equipments - which employ no explosives of any type - are given. Vaporization is the maximally robust defensive option, and may be invoked to negate threat objects not observed until little time is left until Earth-strike, and pulverization-with-dispersal has proven inadequate. Physically larger threats may be vaporized with nuclear explosives. No contemporary technical means of any kind appear capable of directly dispersing the -100 km diameter scale Charon- class cometary objects recently observed in the outer solar system, although such objects may be deflected to defensively useful extents. Means of implementing defenses of each of these types are proposed for specificity, and areas for optimization noted. Biospheric impacts of threat object debris are briefly considered, for bounding purposes. Experiments are suggested on cometary and asteroidal objects.
Date: May 24, 1995
Creator: Teller, E.; Wood, L.; Ishikawa, M. & Hyde, R.
Partner: UNT Libraries Government Documents Department

Three Problems: Nuclear Energy, National Defense and International Cooperation

Description: A little more than half a century into the Nuclear Age, we cannot look back on a peaceful period, but we can say that the second (nuclear) half of the century has seen much less violence than the first half with its two violent wars. Also the second half of the century has seen the fortunate ending of the Cold War. But as to the future, we are left with three great questions. (1) How can the world be provided with ample energy? (2) How can we avoid the potentially devastating sudden applications of new destructive technologies? And finally, (3) How can we preserve the development of the world's new potentialities without producing a continuation of violent conflicts? The development of nuclear reactors appears to provide a most interesting new initiative to make energy available to every one. The reality of this promise is at least indicated by progress in France where electricity now is 80% ''nuclear.'' Unfortunately, fear of radioactivity and fear of weapons proliferation has turned public opinion in many parts of the world against nuclear energy. The fear of radioactivity seems to be exaggerated, as indicated, for instance, in the recent international conference in Vienna on the consequences of Chernobyl. The conference concluded that most of the anticipated difficulties (cancer and congenital malformation) have been grossly exaggerated. In my opinion, both the worry about radioactivity and the worry about massive military use of reactor products can be solved. There remain further real difficulties connected with expense and the availability of expertise that may be needed to handle nuclear reactors that may be absent in many parts of the world. I believe that all these problems can be solved. The three major accidents, Windscale in England in 1957, Three-Mile Island in Pennsylvania in 1979, and Chernobyl in Russia ...
Date: September 6, 1999
Creator: Teller, E.
Partner: UNT Libraries Government Documents Department

Equations of State of Elements Based on the Generalized Fermi-Thomas Theory

Description: The Fermi-Thomas model has been used to derive the equation of state of matter at high pressures and at various temperatures. Calculations have been carried out both without and with the exchange terms. Discussion of similarity transformations lead to the virial theorem and to correlation of solutions for different Z-values.
Date: April 30, 1949
Creator: Feynman, R.P.; Metropolis, N. & Teller, E.
Partner: UNT Libraries Government Documents Department

High energy-density physics: From nuclear testing to the superlasers

Description: We describe the role for the next-generation ``superlasers`` in the study of matter under extremely high energy density conditions, in comparison to previous uses of nuclear explosives for this purpose. As examples, we focus on three important areas of physics that have unresolved issues which must be addressed by experiment: Equations of state, hydrodynamic mixing, and the transport of radiation. We will describe the advantages the large lasers will have in a comprehensive experimental program.
Date: October 20, 1995
Creator: Campbell, E.M.; Holmes, N.C.; Libby, S.B.; Remington, B.A. & Teller, E.
Partner: UNT Libraries Government Documents Department

High energy-density physics: From nuclear testing to the superlasers

Description: The authors describe the role for the next-generation ``superlasers`` in the study of matter under extremely high energy density conditions, in comparison to previous uses of nuclear explosives for this purpose. As examples, the authors focus on three important areas of physics that have unresolved issues which must be addressed by experiment: equations of state, turbulent hydrodynamics, and the transport of radiation. They describe the advantages the large lasers will have in a comprehensive experimental program.
Date: August 14, 1995
Creator: Teller, E.; Campbell, E.M.; Holmes, N.C.; Libby, S.B. & Remington, B.A.
Partner: UNT Libraries Government Documents Department

Critical dimensions of water-tamped slabs and spheres of active material

Description: The magnitude and distribution of the fission rate per unit area produced by three energy groups of moderated neutrons reflected from a water tamper into one side of an infinite slab of active material is calculated approximately in section II. This rate is directly proportional to the current density of fast neutrons from the active material incident on the water tamper. The critical slab thickness is obtained in section III by solving an inhomogeneous transport integral equation for the fast-neutron current density into the tamper. Extensive use is made of the formulae derived in The Mathematical Development of the End-Point Method by Frankel and Goldberg. In section IV slight alterations in the theory outlined in sections II and III were made so that one could approximately compute the critical radius of a water-tamper sphere of active material. The derived formulae were applied to calculate the critical dimensions of water-tamped slabs and spheres of solid UF{sub 6} leaving various (25) isotope enrichment fractions.
Date: August 6, 1946
Creator: Greuling, E.; Argo, H.; Chew, G.; Frankel, M. E.; Konopinski, E. J.; Marvin, C. et al.
Partner: UNT Libraries Government Documents Department