Cold fusion

International Nuclear Information System (INIS)

Koster, J.

1989-01-01

In this contribution the author the phenomenom of so-called cold fusion, inspired by the memorable lecture of Moshe Gai on his own search for this effect. Thus much of what follows was presented by Dr. Gai; the rest is from independent reading. What is referred to as cold fusion is of course the observation of possible products of deuteron-deuteron (d-d) fusion within deuterium-loaded (dentended) electrodes. The debate over the two vanguard cold fusion experiments has raged under far more public attention than usually accorded new scientific phenomena. The clamor commenced with the press conference of M. Fleishmann and S. Pons on March 23, 1989 and the nearly simultaneous wide circulation of a preprint of S. Jones and collaborators. The majority of work attempting to confirm these observations has at the time of this writing yet to appear in published form, but contributions to conferences and electronic mail over computer networks were certainly filled with preliminary results. To keep what follows to a reasonable length the author limit this discussion to the searches for neutron (suggested by ref. 2) or for excessive heat production (suggested by ref. 1), following a synopsis of the hypotheses of cold fusion

Review for 'Nattoh' model and experimental findings during cold fusion

International Nuclear Information System (INIS)

Matsumoto, Takaaki

1993-01-01

A review is described for the Nattoh model that provides the framework of the mechanisms of cold fusion. The model classifies the reactions into two categories: fundamental and associated reactions. The former involves the new 'hydrogen-catalyzed' fusion reaction and the chain-reactions of hydrogens. And extremely exciting physics are involved in the latter. Furthermore experimental findings are described. (author)

Cold fusion research

International Nuclear Information System (INIS)

1989-11-01

I am pleased to forward to you the Final Report of the Cold Fusion Panel. This report reviews the current status of cold fusion and includes major chapters on Calorimetry and Excess Heat, Fusion Products and Materials Characterization. In addition, the report makes a number of conclusions and recommendations, as requested by the Secretary of Energy

Cold fusion in perspective

International Nuclear Information System (INIS)

Sanford, L.

1989-01-01

Since early April a great deal of excitement has been created over the Fleischmann/Pons cold fusion experiment, which if it performs as advertised, could turn out to be mankind's best hope of heading off the energy crisis scheduled for early in the next century. Dozens of groups around the world are now attempting to duplicate the experiment to see if Fleischmann and Pons' discovery is an experimental mistake, an unknown electrochemical effect or a new kind of fusion reaction. This article puts the experiment into the perspective of today and looks at how it might affect the energy scene tomorrow if it should turn out to be commercially exploitable. (author)

Cold fusion

International Nuclear Information System (INIS)

Suh, Suk Yong; Sung, Ki Woong; Kang, Joo Sang; Lee, Jong Jik

1995-02-01

So called 'cold fusion phenomena' are not confirmed yet. Excess heat generation is very delicate one. Neutron generation is most reliable results, however, the records are erratic and the same results could not be repeated. So there is no reason to exclude the malfunction of testing instruments. The same arguments arise in recording 4 He, 3 He, 3 H, which are not rich in quantity basically. An experiment where plenty of 4 He were recorded is attached in appendix. The problem is that we are trying to search cold fusion which is permitted by nature or not. The famous tunneling effect in quantum mechanics will answer it, however, the most fusion rate is known to be negligible. The focus of this project is on the theme that how to increase that negligible fusion rate. 6 figs, 4 tabs, 1512 refs. (Author)

Cold fusion

Energy Technology Data Exchange (ETDEWEB)

Suh, Suk Yong; Sung, Ki Woong; Kang, Joo Sang; Lee, Jong Jik [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-02-01

So called `cold fusion phenomena` are not confirmed yet. Excess heat generation is very delicate one. Neutron generation is most reliable results, however, the records are erratic and the same results could not be repeated. So there is no reason to exclude the malfunction of testing instruments. The same arguments arise in recording {sup 4}He, {sup 3}He, {sup 3}H, which are not rich in quantity basically. An experiment where plenty of {sup 4}He were recorded is attached in appendix. The problem is that we are trying to search cold fusion which is permitted by nature or not. The famous tunneling effect in quantum mechanics will answer it, however, the most fusion rate is known to be negligible. The focus of this project is on the theme that how to increase that negligible fusion rate. 6 figs, 4 tabs, 1512 refs. (Author).

The status of 'cold fusion'

International Nuclear Information System (INIS)

Nagel, David J.

1998-01-01

The questions raised by reports of nuclear reactions at low energies, so called 'cold fusion', are not yet answered to the satisfaction of many scientists. Further experimental investigations of these and related questions seems desirable, at least for scientific if not practical reasons. Properly conducted, such investigations would be indistinguishable from normal research. They would yield information germane to accepted areas of scientific inquiry and technological utility

Fusion chain reaction - a chain reaction with charged particles

International Nuclear Information System (INIS)

Peres, A.; Shvarts, D.

1975-01-01

When a DT-plasma is compressed to very high density, the particles resulting from nuclear reactions give their energy mostly to D and T ions, by nuclear collisions, rather than to electrons as usual. Fusion can thus proceed as a chain reaction, without the need of thermonuclear temperatures. In this paper, we derive relations for the suprathermal ion population created by a fusion reaction. Numerical integration of these equations shows that a chain reaction can proceed in a cold infinite DT-plasma at densities above 8.4x10 27 ions.cm -3 . Seeding the plasma with a small amount of 6 Li reduces the critical density to 7.2x10 27 ions.cm -3 (140000times the normal solid density). (author)

Cold fusion in symmetric 90Zr induced reactions

International Nuclear Information System (INIS)

Keller, J.G.; Schmidt, K.H.; Hessberger, F.P.; Muenzenberg, G.; Reisdorf, W.; Clerc, H.G.; Sahm, C.C.

1985-08-01

Excitation functions for evaporation residues were measured for the reactions 90 Zr+ 89 Y, 90 Zr, 92 Zr, 96 Zr, and 94 Mo. Deexcitation only by γ radiation was found for the compound nuclei 179 Au, 180 Hg, 182 Hg, and 184 Pb. The cross sections for this process were found to be considerably larger than predicted by a statistical-model calculation using standard parameters for the γ-strength function. Fusion probabilities as well as fusion-barrier distributions were deduced from the measured cross sections. There are strong nuclear structure effects in subbarrier fusion. For energies far below the fusion barrier the increase of the fusion probabilities with increasing energy is found to be much steeper than predicted by WKB calculations. As a by-product of this work new α-spectroscopic information could be obtained for neutron deficient isotopes between Ir and Pb. (orig.)

Cold fusion saga: Lesson in science

International Nuclear Information System (INIS)

Lewenstein, B.V.

1992-01-01

A news conference at the University of Utah on March 23, 1989, ignited an explosion of scientific tempers almost as intense as the topic up for discussion - nuclear fusion. Two electrochemists, B. Stanley Pons and Martin Fleischmann, announced they had discovered a method for creating nuclear fusion at room temperature, using simple equipment available in any high school laboratory. This could mean unlimited supplies of cheap electricity in the future. The announcement set off a chain reaction involving the news media and scientists worldwide, notes Bruce V. Lewenstein of Cornell University. For the first six weeks of the saga, Lewenstein recalls, competing claims, counterclaims, and interpretations led to what many headline writers referred to as fusion confusion. Media attention faded gradually, but scientific attention didn't. Over the next two years, laboratory experiments, scientific reports, meetings, and panels kept the issue boiling. The cold-fusion saga, while more intense than some scientific research, followed familiar paths, Lewenstein believes. News coverage, political maneuvering, competition among scientists, parent rights, arguments about the interpretation of experiments - all points of contention - are normal, indeed, one might almost say integral, to modern science, he says. This is the stuff science is made of, he adds. And for those disturbed by the implications, Lewenstein cautions that cold-fusion may be the harbinger for other high-profile science, such as high-temperature superconductors

Cold fusion anomalies more perplexing than ever

International Nuclear Information System (INIS)

Dagani, R.

1989-01-01

This article addresses the debate over research on cold fusion. Analysis is made of the research efforts that have taken place since cold fusion was first thought to have been discovered in Utah. Research in the Soviet Union on the cold fusion phenomenon is also discussed

Recent cold fusion claims: are they valid?

International Nuclear Information System (INIS)

Kowalski, Ludwik

2006-01-01

Cold fusion consists of nuclear reactions occurring in solid metals loaded with hydrogen. Considerable progress has been made in that area in the last ten years. This 2004 paper summarizes recent claims without attempting to evaluate their validity. The manuscript was submitted to seven physics journals. Unfortunately, the editors rejected it without the benefit of the usual peer-review process. (author)

Cold versus hot fusion deuterium branching ratios

International Nuclear Information System (INIS)

Fox, H.; Bass, R.

1995-01-01

A major source of misunderstanding of the nature of cold nuclear fusion has been the expectation that the deuterium branching ratios occurring within a palladium lattice would be consistent with the gas-plasma branching ratios. This misunderstanding has led to the concept of the dead graduate student, the 1989's feverish but fruitless search for neutron emissions from cold fusion reactors, and the follow-on condemnation of the new science of cold fusion. The experimental facts are that in a properly loaded palladium lattice, the deuterium fusion produces neutrons at little above background, a greatly less-than-expected production of tritium (the tritium desert), and substantially more helium-4 than is observed in hot plasma physics. The experimental evidence is now compelling (800 reports of success from 30 countries) that cold nuclear fusion is a reality, that the branching ratios are unexpected, and that a new science is struggling to be recognized. Commercialization of some types of cold fusion devices has already begun

Highlights of papers presented at the workshop on cold fusion phenomena

International Nuclear Information System (INIS)

1989-09-01

This report contains highlights of formal oral papers presented at the Workshop on Cold Fusion Phenomena, hosted by Los Alamos National Laboratory and held May 23--25, 1989, in Santa Fe, New Mexico. General topics covered are: physics of fusion reactions; neutron and gamma-ray spectroscopy; colorimetry; and applicable condensed-matter physics, electrochemistry, and analytical chemistry

Cold Fusion Has Now Come Out of the Cold

Science.gov (United States)

Storms, Edmund

2003-10-01

The phenomenon called cold fusion or LENR (Low-Energy-Nuclear-Reaction) has now achieved a level of reproducibility and understanding that warrants re-examination of the claims. A summary of what is known and want is being done worldwide to obtain more knowledge will be given. Rather than disappearing as better data are obtained, the effects are becoming more reproducible and of greater magnitude. Justification for this claim can be obtained at www.LENR-CANR.org. The phenomenon is too important to ignore any longer even though it conflicts with conventional theory.

Barrier for cold-fusion production of superheavy elements

International Nuclear Information System (INIS)

Ichikawa, Takatoshi; Iwamoto, Akira; Moeller, Peter; Sierk, Arnold J.

2005-01-01

We estimate the fusion-barrier height B fu (two-body) for approaching ions in cold-fusion reactions in a model where the projectile deformation and quadrupole zero-point vibrational energy are taken into account. This barrier height is defined as the barrier energy at the target and projectile separation distance where an original oblate deformation of projectile and/or target caused by a repulsive Coulomb force turns into a large prolate deformation caused by the attractive nuclear force as the target and projectile come closer. The instability develops before touching because the attractive short-range nuclear force overcomes the repulsive Coulomb force and the shape-stabilizing effect of shell structure. The shell structure of the doubly magic 208 Pb target is sufficiently strong that its shape remains very close to spherical in all cases studied here. The fusion potential for approaching ions in the two-body channel is calculated in the macroscopic-microscopic model with the quadrupole vibrational zero-point energy obtained in the WKB approximation. We compare our results with data from 10 experimental cold-fusion reactions and with the Bass barriers. Differences and similarities between the Yukawa-plus-exponential model and the Bass model are discussed. We also calculate five-dimensional potential-energy surfaces for the single compound system and show that well-established fission and fusion valleys are both present. For heavy systems, B fu (two-body) becomes lower than the fission barrier just beyond the ground state of the compound system. In the vicinity of this transition, the optimum collision energy for formation of evaporation residues can be expected to depend in a delicate fashion on the interplay among B fu (two-body) , the fusion valley, the fission barrier of the compound system, and the one- and two-neutron separation energies S 1n and S 2n . We discuss these issues in detail and calculate fission-barrier heights. Except for reactions in which

Cold fusion valleys for the synthesis of Z=118 isotopes

International Nuclear Information System (INIS)

Gherghescu, R.

2005-01-01

Cold fusion reactions are investigated with the goal to synthesize Z=118 isotopes with neutron numbers N=162, 168, 172, 176. Potential energy surfaces are calculated as the result of dynamic minimization with independent deformations of the target and projectile, small semi-axis of the projectile and distance between centers as degrees of freedom. An advanced binary macroscopic-microscopic method is used to obtain the deformation energy and the Werner-Wheeler approximation yield the mass tensor. Charge asymmetry is varied for the same mass asymmetry channel which belongs to a given energy valley. The highest penetrability values are obtained for cold fusion channels with Sn, Te and Xe isotopes as projectiles

Cold fusion

International Nuclear Information System (INIS)

Bush, R.T.

1991-01-01

The transmission resonance model (TRM) is combined with some electrochemistry of the cathode surface and found to provide a good fit to new data on excess heat. For the first time, a model for cold fusion not only fits calorimetric data but also predicts optimal trigger points. This suggests that the model is meaningful and that the excess heat phenomenon claimed by Fleischmann and Pons is genuine. A crucial role is suggested for the overpotential and, in particular, for the concentration overpotential, i.e., the hydrogen overvoltage. Self-similar geometry, or scale invariance, i.e., a fractal nature, is revealed by the relative excess power function. Heat bursts are predicted with a scale invariance in time, suggesting a possible link between the TRM and chaos theory. The model describes a near-surface phenomenon with an estimated excess power yield of ∼1 kW/cm 3 Pd, as compared to 50 W/cm 3 of reactor core for a good fission reactor. Transmission resonance-induced nuclear transmutation, a new type of nuclear reaction, is strongly suggested with two types emphasized: transmission resonance-induced neutron transfer reactions yielding essentially the same end result as Teller's hypothesized catalytic neutron transfer and a three-body reaction promoted by standing de Broglie waves. In this paper suggestions for the anomalous production of heat, particles, and radiation are given

Once more about cold nuclear fusion

International Nuclear Information System (INIS)

Brudanin, V.B.; Bystritsky, V.M.; Egorov, V.G.

1989-01-01

The results of the experiments on the search for cold nuclear d-d fusion in chemically pure titanium are given both for electrolysis of heavy water D 2 O and for titanium saturation with gaseous deuterium. The saturation took place at the temperature of 77K and pressure of 50 and 150 atm. A round of experiments with temperature varying from 1 to 600 atm was carried out. The limiting values of the partial rate of the nuclear reaction of d-d fusion with neutron production were obtained per deuteron (at the 95% confidence level): λ f ≤4x10 -25 s -1 (experiment with electrolysis), λ f ≤7x10 -28 s -1 (experiment with gaseous deuterium). 7 refs.; 5 figs.; 2 tabs

Synthesis of superheavy elements by cold fusion

Energy Technology Data Exchange (ETDEWEB)

Hofmann, S [Gesellschaft fuer Schwerionenforschung (GSI), Helmholtzzentrum fuer Schwerionenforschung Gmbh (Germany)

2009-12-31

The nuclear shell model predicts that the next doubly magic shell-closure beyond {sup 208}Pb is at the proton number Z=114, 120, or 126 and at the neutron number N=172 or 184. The outstanding aim of experimental investigations is the exploration of this region of spherical 'Super Heavy Elements' (SHEs). Using cold fusion reactions which are based on lead and bismuth targets, the new elements from 107 to 112 were synthesized at GSI in Darmstadt, Germany. Some of these results were confirmed at RIKEN in Wako, Japan, where also a relatively neutron-deficient isotope of element 113 was synthesized. In hot fusion reactions of {sup 48}Ca projectiles with actinide targets, a more neutron-rich isotope of element 112 and the new elements from 113 to 116 and even 118 were produced at FLNR in Dubna, Russia. Recently, part of these hot fusion data, which represent the first identification of nuclei located on the predicted island of SHEs, were confirmed in two independent experiments. The decay data reveal that for the heaviest elements, the dominant decay mode is alpha emission rather than fission. The decay properties as well as reaction cross-sections are compared with results of theoretical studies.

Cold-fusion as safe and hazardless energy-source of the 21st century

International Nuclear Information System (INIS)

Gupta, R.C.; Gupta, Sushant

2012-01-01

Out of the two processes for nuclear-energy; nuclear-fission is plagued with problem of nuclear-radiation hazard, whereas though nuclear-fusion is safe but almost impossible to be done on earth specially at room- temperature. In 1989, two scientists Fleischmann and Pons in USA proposed a table-top, room temperature electrolysis-experiment of heavy-water with palladium-electrode; this is commonly called cold-fusion wherein nuclear-fusion is said to be taking place. This created a big storm and controversy in the scientific community. Initially the cold-fusion was heavily criticized and several objections (such as: non-reproducibility, non-observation of telltale signature of nuclear-reaction) were raised. The research-work of McKubre and others have clarified the objections and have established that for cold-fusion to take place certain threshold conditions (such as purity of electrode, current-density, deuterium to palladium loading ratio) needs to be satisfied. In due course of time, the Truth prevailed and the cold-fusion got more and more support by many scientists in several countries including India (BARC historic role has been appreciated worldwide). Biggest objection, however, was lack of a proper theory for how Coulomb-repulsion is overcome in cold-fusion. A possible explanation for how the Coulomb-repulsion is overcome, is given in this paper; which is based on a new-found Gupta-Dinu effect, which is a natural outcome of special-relativity via modification in Lorentz force formula. The recent nuclear-accidents have raised international-opinion against nuclear-fission, whereas sin-like hot-fusion on earth is not possible. Now it seems that ultimately it is the cold-fusion which will provide hazardless neat and cheap energy for the 21 st century and India could play a leading role in this direction. (author)

Cold fusion

International Nuclear Information System (INIS)

Seo, Suk Yong; You, Jae Jun

1996-01-01

Nearly every technical information is chased in the world. All of them are reviewed and analyzed. Some of them are chosen to study further more to review every related documents. And a probable suggestion about the excitonic process in deuteron absorbed condensed matter is proposed a way to cold fusion. 8 refs. (Author)

Cold fusion method

International Nuclear Information System (INIS)

Takahashi, Akihito.

1994-01-01

A Pt wire electrode is supported from the periphery relative to a Pd electrode by way of a polyethylene or teflon plate in heavy water, and electrolysis is applied while varying conditions successively in a sawteeth fashion at an initial stage, and after elapse of about one week, a pulse current is supplied to promote nuclear reaction and to generate excess heat greater than a charged electric power. That is, small amount of neutron emission is increased and electrolytic cell temperature is elevated by varying the electrolysis conditions successively in the sawteeth fashion at the initial stage. In addition, when the pulse electric current is supplied after elapse of about one week, the electrolytic cell temperature is abnormally elevated, so that the promotion of nuclear reaction phenomenon and the generation of excess heat greater than the charged electric power are recognized. Then, a way to control power level and time fluctuation of cold fusion is attained, thereby contributing to development of a further method for generating excess heat as desired. In addition, it contributes to a development for a method of obtaining such an excess heat that can be taken as a new energy. (N.H.)

Does cold nuclear fusion exist?

International Nuclear Information System (INIS)

Brudanin, V.B.; Bystritskij, V.M.; Egorov, V.G.; Shamsutdinov, S.G.; Shyshkin, A.L.; Stolupin, V.A.; Yutlandov, I.A.

1989-01-01

The results of investigation of cold nuclear fusion on palladium are given both for electrolysis of heavy water D 2 O and mixture D 2 O + H 2 O) (1:1) and for palladium saturation with gaseous deuterium. The possibility of existance of this phenomenon was examined by detection of neutrons and gamma quanta from reactions: d + d → 3 He + n + 3.27 MeV, p + d → 3 He + γ + 5.5 MeV. Besides these reactions were identified by measuring the characteristic X radiation of palladium due to effect of charged products 3 He, p, t. The upper limits of the intensities of hypothetical sources of neutrons and gamma quanta at the 95% confidence level were obtained to be Q n ≤ 2x10 -2 n/sxcm 3 Pd, Q γ ≤ 2x10 -3 γ/sxcm 3 Pd. 2 refs.; 4 figs.; 2 tabs

Cold fusion: Need to keep door wide open

International Nuclear Information System (INIS)

Jones, S.E.

1992-01-01

Steven E. Jones of Brigham Young University in Provo, Utah, began work on cold fusion in 1986. Although insisting his work is markedly different from that of Stanley Pons and Martin Fleischmann at the nearby University of Utah, he nevertheless was tarred by the same brush that besmirched their sensational revelations in 1989. Whereas we were searching for tiny nuclear effects, they were looking for heat production, he explains. In no way, he insists, does his work substantiate the bold claims of heat generation by cold fusion in an electrochemical cell. In fact, Jones doublts Fleischmann and Pons' claims and sees evidence of either self-deception or hype in their actions. He adds, For useful energy production, thermonuclear (hot) fusion remains for more promising than that cold fusion claims of Pons and Fleischmann. But at the same time, Jones finds it necessary to appeal for tolerance for researchers brave enough to continue in the now unfashionable field of cold fusion

Cold fusion reactors and new modern physics

OpenAIRE

Huang Zhenqiang Huang Yuxiang

2013-01-01

The author of the "modern physics classical particle quantization orbital motion model general solution", referred to as the “new modern physics” a book. “The nuclear force constraint inertial guidance cold nuclear fusion collides” patent of invention referred to as the “cold nuclear fusion reactor” detailed technical data. Now provide to you, hope you help spread and the mainstream of modern physics of academic and fusion engineering academic communication. We work together to promote the c...

Cold fusion catalyzed by muons and electrons

International Nuclear Information System (INIS)

Kulsrud, R.M.

1990-10-01

Two alternative methods have been suggested to produce fusion power at low temperature. The first, muon catalyzed fusion or MCF, uses muons to spontaneously catalyze fusion through the muon mesomolecule formation. Unfortunately, this method fails to generate enough fusion energy to supply the muons, by a factor of about ten. The physics of MCF is discussed, and a possible approach to increasing the number of MCF fusions generated by each muon is mentioned. The second method, which has become known as ''Cold Fusion,'' involves catalysis by electrons in electrolytic cells. The physics of this process, if it exists, is more mysterious than MCF. However, it now appears to be an artifact, the claims for its reality resting largely on experimental errors occurring in rather delicate experiments. However, a very low level of such fusion claimed by Jones may be real. Experiments in cold fusion will also be discussed

Mission to Mars by catalyzed nuclear reactions of the commercialized cold fusion power

International Nuclear Information System (INIS)

Woo, Tae Ho

2016-01-01

The chemical compound source is deficient to reach to the power as much as the journey to Mars, unless the massive equipment is installed like the nuclear fusion reactor. However, there is very significant limitations of making up the facility due to the propellant power. Therefore, the light and cheap energy source, Low energy nuclear reactions (LENRs), powered rocket has been proposed. In this paper, the power conditions by LENRs are analyzed. After the successful Apollo mission to Moon of the National Aeronautics and Space Administration (NASA) in the U.S. government, the civilian companies have proposed for the manned mission to Mars for the commercial journey purposes. The nuclear power has been a critical issue for the energy source in the travel, especially, by the LENR of LENUCO, Champaign, USA. As the velocity of the rocket increases, the mass flow rate decreases. It could be imaginable to take the reasonable velocity of spacecraft. The energy of the travel system is and will be created for the better one in economical and safe method. There is the imagination of boarding pass for spacecraft ticket shows the selected companies of cold fusion products. In order to solve the limitations of the conventional power sources like the chemical and solar energies, it is reasonable to design LENR concept. Since the economical and safe spacecraft is very important in the long journey on and beyond the Mars orbit, a new energy source, LENR, should be studied much more

Mission to Mars by catalyzed nuclear reactions of the commercialized cold fusion power

Energy Technology Data Exchange (ETDEWEB)

Woo, Tae Ho [Yonsei University, Wonju (Korea, Republic of)

2016-05-15

The chemical compound source is deficient to reach to the power as much as the journey to Mars, unless the massive equipment is installed like the nuclear fusion reactor. However, there is very significant limitations of making up the facility due to the propellant power. Therefore, the light and cheap energy source, Low energy nuclear reactions (LENRs), powered rocket has been proposed. In this paper, the power conditions by LENRs are analyzed. After the successful Apollo mission to Moon of the National Aeronautics and Space Administration (NASA) in the U.S. government, the civilian companies have proposed for the manned mission to Mars for the commercial journey purposes. The nuclear power has been a critical issue for the energy source in the travel, especially, by the LENR of LENUCO, Champaign, USA. As the velocity of the rocket increases, the mass flow rate decreases. It could be imaginable to take the reasonable velocity of spacecraft. The energy of the travel system is and will be created for the better one in economical and safe method. There is the imagination of boarding pass for spacecraft ticket shows the selected companies of cold fusion products. In order to solve the limitations of the conventional power sources like the chemical and solar energies, it is reasonable to design LENR concept. Since the economical and safe spacecraft is very important in the long journey on and beyond the Mars orbit, a new energy source, LENR, should be studied much more.

Cold nuclear fusion

Energy Technology Data Exchange (ETDEWEB)

Tsyganov, E.N., E-mail: edward.tsyganov@coldfusion-power.com [Cold Fusion Power, International (United States); Bavizhev, M.D. [LLC “Radium”, Moscow (Russian Federation); Buryakov, M.G. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation); Dabagov, S.B. [RAS P.N. Lebedev Physical Institute, Leninsky pr. 53, 119991 Moscow (Russian Federation); National Research Nuclear University MEPhI, Kashirskoe shosse 31, 115409 Moscow (Russian Federation); Golovatyuk, V.M.; Lobastov, S.P. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation)

2015-07-15

If target deuterium atoms were implanted in a metal crystal in accelerator experiments, a sharp increase in the probability of DD-fusion reaction was clearly observed when compared with the reaction’s theoretical value. The electronic screening potential, which for a collision of free deuterium atoms is about 27 eV, reached 300–700 eV in the case of the DD-fusion in metallic crystals. These data leads to the conclusion that a ban must exist for deuterium atoms to be in the ground state 1s in a niche filled with free conduction electrons. At the same time, the state 2p whose energy level is only 10 eV above that of state 1s is allowed in these conditions. With anisotropy of 2p, 3p or above orbitals, their spatial positions are strictly determined in the lattice coordinate system. When filling out the same potential niches with two deuterium atoms in the states 2p, 3p or higher, the nuclei of these atoms can be permanently positioned without creating much Coulomb repulsion at a very short distance from each other. In this case, the transparency of the potential barrier increases dramatically compared to the ground state 1s for these atoms. The probability of the deuterium nuclei penetrating the Coulomb barrier by zero quantum vibration of the DD-system also increases dramatically. The so-called cold nuclear DD-fusion for a number of years was registered in many experiments, however, was still rejected by mainstream science for allegedly having no consistent scientific explanation. Finally, it received the validation. Below, we outline the concept of this explanation and give the necessary calculations. This paper also considers the further destiny of the formed intermediate state of {sup 4}He{sup ∗}.

Conventional physics can explain cold fusion excess heat

Science.gov (United States)

Chubb, S. R.

In 1989, when Fleischmann, Pons and Hawkins (FP), claimed they had created room temperature, nuclear fusion in a solid, a firestorm of controversy erupted. Beginning in 1991, the Office of Naval Research began a decade-long study of the FP excess heat effect. This effort documented the fact that the excess heat that FP observed is the result of a form of nuclear fusion that can occur in solids at reduced temperature, dynamically, through a deuteron (d)+d□4He reaction, without high-energy particles or □ rays. A key reason this fact has not been accepted is the lack of a cogent argument, based on fundamental physical ideas, justifying it. In the paper, this question is re-examined, based on a generalization of conventional energy band theory that applies to finite, periodic solids, in which d's are allowed to occupy wave-like, ion band states, similar to the kinds of states that electrons occupy in ordinary metals. Prior to being experimentally observed, the Ion Band State Theory (IBST) of cold fusion predicted a potential d+d□4He reaction, without high energy particles, would explain the excess heat, the 4He would be found in an unexpected place (outside heat-producing electrodes), and high-loading, x□1, in PdDx, would be required.

Some considerations of ''cold fusion'' including the calculation of fusion rates in molecules of hydrogen isotopes

International Nuclear Information System (INIS)

Cowley, S.C.; Kulsrud, R.M.

1989-11-01

We calculate the fusion reaction rates in molecules of hydrogen isotopes. The rates are calculated analytically (for the first time) as an asymptotic expansion in the ratio of the electron mass to the reduced mass of the nucleii. The fusion rates of the P-D, D-D, and D-T reactions are given for a variable electron mass by a simple analytic formula. However, we do not know any mechanism by which a sufficiently localized electron in solid can have an 'effective mass' large enough to explain the result of Fleischman and Pons (FP). This calculation indicates that P-D rates should exceed D-D rates for D-D fusion rates less than approximately 10 -23 per molecule per second. The D-D fusion rate is enhanced by a factor of 10 5 at 10,000 degree K if the excited vibrational states are populated with a Boltzmann distribution and the rotational excitations suppressed. The suggestion that experimental results could be explained by bombardment of cold deuterons by kilovolt deuterons is shown to be an unlikely from an energetic point of view. 12 refs., 3 figs., 1 tab

A theoretical study of cold nuclear fusion using barrier penetration approach

International Nuclear Information System (INIS)

Gupta, S.K.; Gupta, R.K.

1989-06-01

The cold nuclear fusion process is investigated in terms of barrier penetration calculations by considering both the deuteron-molecule and colliding deuteron-deuteron atoms. Atomic collisions with strongly screened interatomic potential and the resonant state formation can bring agreement with present experimental results. Analysis of the data in terms of the reaction rates is also discussed. (author). 13 refs, 1 tab

Effect of deformations on the compactness of odd-Z superheavy nuclei formed in cold and hot fusion reactions

Science.gov (United States)

Kaur, Gurjit; Sandhu, Kirandeep; Sharma, Manoj K.

2018-03-01

Using the extended fragmentation theory, the compactness of hot and cold fusion reactions is analyzed for odd-Z nuclei ranging Z = 105- 117. The calculations for the present work are carried out at T = 0MeV and ℓ = 0 ħ, as the temperature and angular momentum effects remain silent while addressing the orientation degree of freedom (i.e. compact angle configuration). In the hot fusion, 48Ca (spherical) + actinide (prolate) reaction, the non-equatorial compact (nec) shape is obtained for Z = 113 nucleus. On the other hand, Z > 113 nuclei favor equatorial compact (ec) configuration. The distribution of barrier height (VB) illustrate that the ec-shape is obtained when the magnitude of quadrupole deformation of the nucleus is higher than the hexadecupole deformation. In other words, negligible or small -ve β4-deformations support ec configurations. On the other hand, large (+ve) magnitude of the β4-deformation suggests that the configuration appears for compact angle θc < 90 °, leading to nec structure. Similar deformation effects are observed for Bi-induced reactions, in which not belly-to-belly compact (nbbc) configurations are seen at θc = 42 °. In addition to the effect of β2 and β4-deformations, the exclusive role of octupole deformations (β3) is also analyzed. The β3-deformations do not follow the reflection symmetry as that of β2 and β4, leading to the possible occurrence of compact configuration within 0° to 180° angular range.

A dynamical theory of incomplete fusion reactions: The breakup-fusion reaction approach

International Nuclear Information System (INIS)

Udagawa, T.

1984-01-01

A dynamical theory of partial fusion reactions is presented, which may fill the gap between direct and compound nuclear reaction theories. With the new theory one can calculate partial fusion taking place in three-body (and many more) channels reached via direct reactions, e.g., breakup and knockout reactions. The authors present first the results for the cross section for such reactions, taking as an example breakup followed by fusion. They then discuss a physical picture which emerges from their theory, namely that the partial fusion reactions, particularly of the massive-transfer type, take place in a so-called deep peripheral region. It is also shown that the deep peripheral character of such processes diminishes as the mass of the fused system decreases, so that the reactions essentially evolve to the usual peripheral character. Finally, comparisons are made of results of numerical calculations with experimental data, taking as an example the /sup 159/Tb(/sup 14/N,α) reaction with E/sub lab/ = 95 MeV

Mechanisms of cold fusion: comprehensive explanations by the Nattoh model

International Nuclear Information System (INIS)

Matsumoto, Takaaki

1995-01-01

The phenomena of cold fusion seem to be very complicated; inconsistent data between the production rates of heat, neutrons, tritiums and heliums. Our thoughts need to drastically change in order to appropriately understand the mechanisms of cold fusion. Here, a review is described for the Nattoh model, that has been developed extensively to provide comprehensive explanations for the mechanisms of cold fusion. Important experimental findings that prove the model are described. Furthermore several subjects including impacts on other fields are also discussed. (author)

Introducing the book 'Cold fusion and the future'

International Nuclear Information System (INIS)

Rothwell, Jed

2006-01-01

Cold fusion will be the ideal source of energy, provided its introduction can be handled properly. A few cells have shown power density and temperatures suitable for real-world applications. Once these cells can be replicated on demand, commercial development will be straightforward. Manufacturing should not be too demanding, so thousands of companies will compete, and costs will fall quickly. The transition from fossil fuel to cold fusion will be rapid. Many extraordinary new applications will become possible, and seemingly intractable problems such as global warming may be fixed. Some examples will be presented. Public support is essential to funding research, and commercialization. 'Cold Fusion and the Future' is the title of a new book by this author. This paper discusses a few of the topics in the book

Nuclear transmutation. The reality of cold fusion

International Nuclear Information System (INIS)

Mizuno, Tadahiko

1997-01-01

The book is introducing the quest on the way to reality of cold fusion. Another point of author is interaction between the quest and social impacts. After the first report on cold fusion by M. Fleischmann and S. Pons on March 1989, the inspired author started a series of following experiments based on his own characteristic background of electrochemistry. The first experiment from March 25 to April 7, 1989 did not show any indications on neutrons, gamma rays, tritium, and heat. The second experiment was initiated at the underground experimental hall of the linear accelerator facilities. This means the shielding of noises coming from outsides. The neutron of about 2.45 MeV was observed after the 1-month continuation of the experiment. The intensity of neutron was nearly 10 to 20 times of the background noise. Furthermore, there were no changes of signals on heat and tritium before and after the experiments. The closed cell experiment was conducted to keep reliability of the experiment. The experiment started on June 1990. In this case, Tritium signals of 100 times of background noise were observed, however, no meaningful signal on neutrons. Anomalous heat was observed after March 24, 1991, where the electric current was increased up to 6 A. On the other hand, there were no appreciable change in neutron and tritium signals. The solid electrolysis was used in the experiment after May 1992, for its high temperature characteristics, where anomalous heat was observed with a certain probability. The experimental system was upgraded in diagnostic methods after 1994. As a result, particular isotopes related to fission reaction were detected. This fact indicates some kinds of transmutations at very local area of the solid surfaces. The author has also pointed out many reactions for a series of this scientific results responded by, for example, well known professors, scientific societies, mass media, and international conferences. Consequently the reactions had almost smeared

Neutron measurements in search of cold fusion

International Nuclear Information System (INIS)

Anderson, R.E.; Goulding, C.A.; Johnson, M.W.; Butterfield, K.B.; Gottesfeld, S.; Baker, D.A.; Springer, T.E.; Garzon, F.H.; Bolton, R.D.; Leonard, E.M.; Chancellor, T.

1990-01-01

We have conducted a research for neutron emission from cold fusion systems of the electrochemical type and, to a lesser extent, the high-pressure gas cell type. Using a high-efficiency well counter and an NE 213 scintillator, the experiments were conducted on the earth's surface and in a shielded cave approximately 50 ft underground. After approximately 6500 h of counting time, we have obtained no evidence for cold fusion processes leading to neutron production. However, we have observed all three types of neutron data that have been presented as evidence for cold fusion: large positive fluctuations in the neutron counting rate, weak peaks near 2.5 MeV in the neutron energy spectrum, and bursts of up to 145 neutrons in 500-μs intervals. The data were obtained under circumstances that clearly show our results to be data encountered as a part of naturally occurring neutron background, which is due primarily to cosmic rays. Thus, observing these types of data does not, of itself, provide evidence for the existence of cold fusion processes. Artifacts in the data that were due to counter misbehavior were also to lead to long-term ''neutron bursts'' whose time duration varied from several hours to several days. We conclude that any experiments which attempt to observe neutron emission must include strong steps to ensure that the experiments deal adequately with both cosmic-ray processes and counter misbehavior. 13 refs., 14 figs

Cold fusion - todays situation

International Nuclear Information System (INIS)

Malmqvist, K.

1993-01-01

A brief review of the history of cold fusion is given. It is noted that it is not possible to draw any definite conclusions about all the experimental and theoretical details, but that some of the results presented do not seem to be reached according to the normal scientific methods. 6 figs

Fusion - still out in the cold

International Nuclear Information System (INIS)

Townsley, Mike.

1989-01-01

Scepticism over the claims made by Professors Martin Fleischman and Stanley Pons about cold fusion is expressed. The background to their experiment and announcement of their results is given. Other research teams have failed to repeat the experiment which claims that deuterium nuclei fused in a special electrochemical cell. If tritium is also produced, as is claimed, this would have important military implications as tritium is used in hydrogen bombs. Failing cold fusion, there is always the JET project but after 10 years and an expenditure of Pound 600 million that has failed to produce a net energy gain it would be better to spend the money developing renewable energy sources. (U.K.)

Current status of cold fusion

International Nuclear Information System (INIS)

Tsarev, V.A.

1992-01-01

This paper reports that the term cold fusion (CF) was known up to March 1989 as the synonym of muon-catalyzed fusion, suggested by A.D. Sakharov more than 40 years ago. Broad use of this term for the last two years is associated with other kind of phenomena: fusion at ambient room temperature of nuclei of hydrogen isotopes embedded into crystal lattice. Nowadays only few remember the unbelievable resonance in the whole world, caused by the first claims of CF from Utah and associated with hopes of a simple and ecologically safe solution to the energy problems confronting humanity. The range of the interest reflected also the receptivity of our society for scientific ideas and wide development of telecommunication media. Extraordinary simplicity of CF experiments (in sharp contrast with hug complexity and high cost of thermonuclear researches) stimulated fast involvement of a large number of specialists of various profiles. Participation of small groups and even individual enthusiasts disposing of only simplest physical and chemical equipment became possible. Figuratively speaking, everybody with a pair of strong hands and a spade had a chance to find his nugget of gold in this Klondike. As a result: passion, rush and a very nonuniform composition of participants in this race for cold fusion, far from being all property prepared and having sense of responsibility

Window of cold nuclear fusion and biased-pulse electrolysis experiment

International Nuclear Information System (INIS)

Takahashi, Akito; Jida, Toshiyuki; Maekawa, Fujio; Sugimoto, Hisashi; Yoshida, Shigeo

1989-01-01

Based on the electron screening effect and the excitation of deuteron harmonic oscillators in palladium lattice, theoretical aspects are given to explain the cold fusion phenomena and the possibility of nuclear heating. A narrow window is proposed to meet ≅ 10 watts per cubic centimeter for the nuclear heating, by the hypothetical excitation-screening model. A relatively wide window is feasible to meet a few fusion events per second per cc under the non-stationary conditions of deuteron-charging and discharging. For stationary lattice conditions, the probability of cold fusion is not feasible at all. To confirm the cold fusion phenomena, a heavy water electrolysis experiment was carried out using biased-pulse-electrolytic currents, expecting the enhancement of cold fusion events under charging and discharging of deuterons. For the neutron detection, a cross-checking system between a recoil-proton scintillation detector and a 3 He thermal neutron detector was employed to see coincident time-patterns of neutron emission from an electrolysis cell. To check the energy of emitted neutrons, pulse height spectrum of the recoil-proton detector was monitored. Up to the D-charging time of 300 hr, neutron yields of 1-2 n/s/cc were obtained for time-intervals of 60-200 hr. From the recoil-proton spectra, it was confirmed that 2.45 MeV neutrons by the D(d, n) 3 He fusion branch were emitted. The observed time-patterns of neutron emission suggest the existence of cold fusion under the charging and discharging conditions. (orig.)

Fusion reaction spectra produced by anisotropic fast ions in the PLT tokamak

International Nuclear Information System (INIS)

Heidbrink, W.W.

1984-02-01

For beam-target fusion reactions, collimated measurements of the energy spectrum of one of the reaction products can provide information on the degree of anisotropy of the reacting beam ions. Measurements of the spectrum of 15 MeV protons produced by reactions between energetic 3 He ions and relatively cold deuterons during fast wave minority heating in the PLT tokamak indicate that the velocity distribution of fast 3 He ions is peaked perpendicular to the tokamak magnetic field

Nuclear structure in cold rearrangement processes in fission and fusion

Energy Technology Data Exchange (ETDEWEB)

Armbruster, P.

1998-11-01

In fission and fusion of heavy nuclei large numbers of nucleons are rearranged at a scale of excitation energy very small compared to the binding energy of the nuclei. The energies involved are less than 40 MeV at nuclear temperatures below 1.5 MeV. The shapes of the configurations in the rearrangement of a binary system into a monosystem in fusion, or vice versa in fission, change their elongations by as much as 8 fm, the radius of the monosystem. The dynamics of the reactions macroscopically described by a potential energy surface, inertia parameters, dissipation, and a collision energy is strongly modified by the nuclear structure of the participating nuclei. Experiments showing nuclear structure effects in fusion and fission of the heaviest nuclei are reviewed. The reaction kinematics and the multitude of isotopes involved are investigated by detector techniques and by recoil spectrometers. The advancement of the latter allows to find very small reaction branches in the range of 10{sup -5} to 10{sup -10}. The experiments reveal nuclear structure effects in all stages of the rearrangement processes. These are discussed pointing to analogies in fusion and fission on the microscopic scale, notwithstanding that both processes macroscopically are irreversible. Heavy clusters, as 132Sn, 208Pb, nuclei with closed shell configurations N=82,126, Z=50,82 survive in large parts of the nuclear rearrangement. They determine the asymmetry in the mass distribution of low energy fission, and they allow to synthesise superheavy elements, until now up to element 112. Experiments on the cold rearrangement in fission and fusion are presented. Here, in the range of excitation energies below 12 MeV the phenomena are observed most convincingly. (orig.)

Conventional sources of fast neutrons in 'cold fusion' experiments

International Nuclear Information System (INIS)

Cribier, M.; Spiro, M.; Favier, J.

1989-04-01

In 'cold fusion' experiments with heavy water a source of neutrons is the dissociation of deuterium induced by alpha particles emitted by natural occurring radioisotopes. We evaluate the rate of fast neutron emission as a function of the concentration of U, Th, Rn in contact with deuterium and discuss the possibility that the neutrons claimed to have been observed in 'cold fusion' experiments could be due to this conventional source

Cold nuclear fusion. Germany 2012

Energy Technology Data Exchange (ETDEWEB)

Petrescu, Florian Ion

2012-07-01

Nuclear fusion is the process by which two or more atomic nuclei join together, or ''fuse'', to form a single heavier nucleus. During this process, matter is not conserved because some of the mass of the fusing nuclei is converted to energy which is released. The binding energy of the resulting nucleus is greater than the binding energy of each of the nuclei that fused to produce it. Fusion is the process that powers active stars. Creating the required conditions for fusion on Earth is very difficult, to the point that it has not been accomplished at any scale for protium, the common light isotope of hydrogen that undergoes natural fusion in stars. In nuclear weapons, some of the energy released by an atomic bomb (fission bomb) is used for compressing and heating a fusion fuel containing heavier isotopes of hydrogen, and also sometimes lithium, to the point of ''ignition''. At this point, the energy released in the fusion reactions is enough to briefly maintain the reaction. Fusion-based nuclear power experiments attempt to create similar conditions using far lesser means, although to date these experiments have failed to maintain conditions needed for ignition long enough for fusion to be a viable commercial power source.

Cold valleys in fusion and fission

International Nuclear Information System (INIS)

Misicu, S.

2003-01-01

The cold fission configuration after the preformation of the fragments resembles a short-lived dinuclear or quasi-molecular system. The most conceivable scission configuration is given by two fission fragments in touching with the symmetry axes aligned (pole-pole orientation). This conclusion was based on the simple argument that this configuration offers the optimal tunneling time, i.e. the difference between the Coulomb barrier and the decay energy Q is minimal. Other orientations are apparently precluded in cold spontaneous fission and should be regarded as quasi-fission doorways in the synthesis of superheavy elements by cold fusion. (orig.)

The DD Cold Fusion-Transmutation Connection

Science.gov (United States)

Chubb, Talbot A.

2005-12-01

LENR theory must explain dd fusion, alpha-addition transmutations, radiationless nuclear reactions, and three-body nuclear particle reactions. Reaction without radiation requires many-body D Bloch+ periodicity in both location and internal structure dependencies. Electron scattering leads to mixed quantum states. The radiationless dd fusion reaction is 2-D Bloch+ -> {}4 He Bloch2+. Overlap between {}4 He Bloch2+ and surface Cs leads to alpha absorption. In the Iwamura et al. studies active deuterium is created by scattering at diffusion barriers.

Measurement of inertial confinement fusion reaction rate

International Nuclear Information System (INIS)

Peng Xiaoshi; Wang Feng; Tang Daorun; Liu Shenye; Huang Tianxuan; Liu Yonggang; Xu Tao; Chen Ming; Mei Yu

2011-01-01

Fusion reaction rate is an important parameter for measuring compression during the implosion in inertial confinement fusion experiment. We have developed a system for fusion reaction history measurement with high temporal resolution. The system is composed of plastic scintillator and nose cone, optical system and streak camera. We have applied this system on the SG-III prototype for fusion reaction rate measuring. For the first time, fusion reaction rate history have been measured for deuterium-tritium filled targets with neutrons yields about 10 10 . We have analyzed possible influence factor during fusion reaction rate measuring. It indicates that the instrument measures fusion reaction bang time at temporal resolutions as low as 30 ps.(authors)

Introducing the book 'Cold fusion and the future'

Energy Technology Data Exchange (ETDEWEB)

Rothwell, Jed

2006-07-01

Cold fusion will be the ideal source of energy, provided its introduction can be handled properly. A few cells have shown power density and temperatures suitable for real-world applications. Once these cells can be replicated on demand, commercial development will be straightforward. Manufacturing should not be too demanding, so thousands of companies will compete, and costs will fall quickly. The transition from fossil fuel to cold fusion will be rapid. Many extraordinary new applications will become possible, and seemingly intractable problems such as global warming may be fixed. Some examples will be presented. Public support is essential to funding research, and commercialization. 'Cold Fusion and the Future' is the title of a new book by this author. This paper discusses a few of the topics in the book.

Experiments in cold fusion

International Nuclear Information System (INIS)

Palmer, E.P.

1986-01-01

The work of Steve Jones and others in muon-catalyzed cold fusion of deuterium and hydrogen suggests the possibility of such fusion catalyzed by ions, or combinations of atoms, or more-or-less free electrons in solid and liquid materials. A hint that this might occur naturally comes from the heat generated in volcanic action in subduction zones on the earth. It is questionable whether the potential energy of material raised to the height of a midocean ridge and falling to the depth of an ocean trench can produce the geothermal effects seen in the volcanoes of subduction zones. If the ridge, the trench, the plates, and the asthenosphere are merely visible effects of deeper density-gradient driven circulations, it is still uncertain that observed energy-concentration effects fit the models

Present knowledge of nuclear cold fusion

International Nuclear Information System (INIS)

Violante, V.; Tripodi, P.; Lombardi, C.

2001-01-01

The nuclear cold fusion, disclosed with clamour in 1989, was successively deemed by most people a blunder. However, the research activities went on, even if softly, and they have been producing more convincing and reproducible results, as well as theoretical models capable of explaining the noticeable anomalies of this phenomenon with respect to the hot fusion. Then, now the demonstration of the phenomenon may be considered valid and accepted. More time is needed to know whether and how this new process may be exploitable to produce energy on an industrial scale [it

A REALISTIC EXAMINATION OF COLD FUSION CLAIMS 24 YEARS LATER

Energy Technology Data Exchange (ETDEWEB)

Shanahan, K.

2012-10-22

On March 29, 1989, chemists Martin Fleischmann and Stanley Pons announced they had discovered an effect whose explanation was required to lie in the realm of nuclear reactions. Their claim, and those subsequent to it of roughly similar nature, became known as ‘cold fusion’. Research continues to this day on this effect, but what has become clear is that whatever it is, it is not a conventional fusion process. Thus the ‘cold fusion’ moniker is somewhat inappropriate and many current researchers in the field prefer the term “Low Energy Nuclear Reactions (LENR)”, although other terms have been coined for it as well. the results developed out of the LENR research do in fact show something is happening to produce signals which might be interpreted as supporting nuclear reactions (which is what encourages and sustains LENR researchers), but which can also be interpreted via a set of unique and interesting conventional processes. The focus of this document is to describe and address recent objections to such processes so that subsequent LENR research can be guided to develop information that will determine whether either set of explanations has merit. It is hoped that criteria delineated herein will aid the USDOE and other agencies in determining if LENR proposals are meritorious and worthy of support or not.

Some theories of cold nuclear fusion

International Nuclear Information System (INIS)

Preparata, G.

1991-01-01

In this paper a review is presented of the main theoretical attempts to describe the phenomenology of cold fusion, whose general structure begins to clearly unravel. The main conclusion is that the approaches that are likely to be of relevance must invoke processes where the elementary components (nuclei and electrons) of condensed matter act in a coherent fashion

LENR/"Cold Fusion" and Modern Physics: A Crisis Within a Crisis

Science.gov (United States)

Mallove, Eugene F. E.

2004-03-01

The primary theorists in the field of Cold Fusion/LENR have generally assumed that the excess heat phenomena is commensurate with nuclear ash (such as helium), whether already identified or presumed to be present but not yet found, and moreover that it can be explained by hydrided metal lattice structures acting coherently. Though this was an excellent initial hypothesis, the commensurate nuclear ash hypothesis has not been proved, and appears to be approximately correct in only a few experiments. At the same time, compelling evidence has also emerged for other microphysical sources of energy that were unexpected by accepted physics. The exemplars have been the work Dr. Randell Mills and his colleagues at BlackLight Power Corporation and Dr. Paulo and Alexandra Correa in Canada.This has led to a crisis within a crisis: Neither "cold fusion" nor "Modern Physics" will be able to explain the full range of experimental data now available---not even the data within "mainstream" cold fusion/LENR per se--- by insisting that the fundamental paradigms of Modern Physics are without significant flaw. The present crisis is of magnitude comparable to the Copernican Revolution. Neither Modern Physics nor Cold Fusion/LENR will survive in their present forms when this long delayed revolution has run its course.

Preliminary results of cold fusion studies using a five module high current electrolytic cell (Paper No. A2)

International Nuclear Information System (INIS)

Nayar, M.G.; Mitra, S.K.; Raghunathan, P.; Krishnan, M.S.; Malhotra, S.K.; Gaonkar, D.G.; Sikka, S.K.; Shyam, A.; Chitra, V.

1989-01-01

A high current modular palladium-nickel electrolytic cell was designed and operated to observe cold fusion reactions. The cathode was made up of palladium (25 per cent)-silver and the anode was made up of porous nickel. Using NaOD in D 2 O (20 per cent) as an electrolyte, the electrolyser was operated continuously at a current of 60 to 65 amps and applied voltage of ∼ 12.5V. The deuterium and oxygen gases produced were carried out of the cell to a recombination unit consisting of burner and condenser. The resultant heavy water was recycled back to the electrolyser. Measurement of the neutron output and tritium content of the electrolyte during and after electrolysis conclusively showed occurrence of cold fusion reactions. Gross neutron to tritium yield ratio was observed to be ∼ 10 -9 which should be taken as a lower limit, because a considerable quantity of tritium carried away by the gas stream could not recovered and taken into account. (M.G.B.). 2 tabs., 2 figs

High temperature superconductivity and cold fusion

International Nuclear Information System (INIS)

Rabinowitz, M.

1990-01-01

There are numerous historical and scientific parallels between high temperature superconductivity (HTSC) and the newly emerging field of cold fusion (CF). Just as the charge carrier effective mass plays an important role in SC, the deuteron effective mass may play a vital role in CF. A new theory including effects of proximity, electron shielding, and decreased effective mass of the fusing nuclei can account for the reported CF results. A quantum-gas model that covers the range from low temperature to superhigh temperature SC indicates an increased T c with reduced dimensionality. A reduced dimensionality effect may also enhance CF. A relation is shown between CF and the significant cluster-impact fusion experiments

Investigation of neutron emission in a cold fusion experiment in palladium

International Nuclear Information System (INIS)

Szustakowski, M.; Farny, J.; Muniak, M.; Nowak, A.; Parys, P.; Skrzeczanowski, W.; Socha, R.; Teter, J.; Wolski, J.; Wolowski, J.; Woryna, E.

1989-01-01

This paper reports on the experiments dealing with performance of nuclear fusion at room temperature actually which create a great sensation and are carried out in various laboratories. This interest arises from the results achieved by Fleischmann and Pons, and it results from their paper that there exists a possibility of obtaining an ignition owing to nuclear fusion reactions during usual electrochemical process--namely the electrolysis of D O with use of the system of Pd-Pt electrodes. From this reason the measurements of the yield and behavior of neutron emission give the information about processes of interest. At the IPPLM the cold fusion experiments have been conducted from the beginning of April 1989. In the first experiment the reliable evidence of neutron emission was obtained. A number of irregularly repeated neutron pulses of the level of 10 5 per pulse was recorded. The measurements of the neutron emission, in this experiment, were performed with the use of three independent methods employing the 2.5 MeV neutron spectrometer, the scintillation neutron detector as well as the nuclear track detector. neutron emission had been first recorded after 106 hours of the electrolysis process of D 2 O

Reaction mechanisms in heavy ion fusion

Directory of Open Access Journals (Sweden)

Lubian J.

2011-10-01

Full Text Available We discuss the reaction mechanisms involved in heavy ion fusion. We begin with collisions of tightly bound systems, considering three energy regimes: energies above the Coulomb barrier, energies just below the barrier and deep sub-barrier energies. We show that channel coupling effects may influence the fusion process at above-barrier energies, increasing or reducing the cross section predicted by single barrier penetration model. Below the Coulomb barrier, it enhances the cross section, and this effect increases with the system’s size. It is argued that this behavior can be traced back to the increasing importance of Coulomb coupling with the charge of the collision partners. The sharp drop of the fusion cross section observed at deep sub-barrier energies is addressed and the theoretical approaches to this phenomenon are discussed. We then consider the reaction mechanisms involved in fusion reactions of weakly bound systems, paying particular attention to the calculations of complete and incomplete fusion available in the literature.

Fusion hindrance in reactions with very heavy ions: Border between normal and hindered fusion

International Nuclear Information System (INIS)

Shen Caiwan; Li Qingfeng; Boilley, David; Shen Junjie; Abe, Yasuhisa

2011-01-01

The fusion hindrance in heavy-ion collisions is studied in the framework of the two-center liquid drop model. It appears that the neck and the radial degrees of freedom might both be hampered by an inner potential barrier on their path between the contact configuration to the compound nucleus. Heavy-ion reactions with and without the two kinds of fusion hindrance are classified through systematic calculations. It is found that the number of reactions without radial fusion hindrance is much smaller than that without neck fusion hindrance, and for both kinds of fusion hindrance the number of reactions without fusion hindrance at small mass-asymmetry parameter α is smaller than that at large α. In the formation of a given compound nucleus, if a reaction with α c is not hindered, then other reactions with α>α c are also not hindered, as is well known experimentally.

Condensed matter nuclear science: Proceedings of the 11. international conference on cold fusion

International Nuclear Information System (INIS)

Biberian, Jean-Paul

2006-01-01

The tenth International Conference on Cold Fusion, ICCF 10, was held in Cambridge and then it appeared to the chairman Jean-Paul Biberian that the ideal choice for the venue of ICCF 11 would be Marseille. He considers that the field had matured and it was obvious that a scientific demonstration of Cold Fusion had been made. He realizes that a lot more is needed to be accomplished in the field of research and technology, but the answers to many of the questions of scientific community are available. It is known for sure that the phenomenon announced in 1989 by Martin Fleischmann and Stan Pons was real. Discoveries since their announcement, in particular the discovery that hydrogen, not only deuterium, may be nuclear active under certain conditions. It had been shown that the simple D + D producing helium reaction was not the only reaction channel. One had observed fission and transmutation beyond doubts, but there are probably more reactions than one currently knows. Several important new results were presented during the conference. The team headed by Irving Dardik confirmed that the super-waves they used in their electrolytic experiment help introducing more heat. Also Iwamura et al. showed new transmutation effects in their experiments of diffusion of deuterium gas through a complex structure of palladium and calcium oxide. A team of Russian scientists claimed that their experiments showed the existence of light monopoles. Czerski and Huke who were working in high-energy physics, discovered CMNS when they lowered the energy of the deuterium beam. They demonstrated that the cross section of the deuterium with deuterated metals was much higher than expected. They came to the conclusion that they were doing indeed cold fusion. Another important contribution was the one from the Vysotskii team from Ukraine, who confirmed their biological transmutation experiments. On the theory front there appears to be many problems. The initial idea of the necessity of high

Recent theoretical and experimental evidence on the cold fusion of elementary particles

International Nuclear Information System (INIS)

Santilli, R.M.

1993-01-01

Recent experiments have shown the apparent existence of the cold fusion/chemical synthesis of protons and electrons into neutrons (plus neutrinos), much along Rutherford's original conception. These findings have received indirect, yet significant experimental confirmations in Bose-Einstein correlations, superconductivity and other fields to warrant additional studies. In this paper we present a quantitative theoretical study of the apparent tendency of all massive particles to form a bound state at small distances which is enhanced at low energy. The study is centrally dependent on the isominkowskian geometrization of the expected nonlocal interactions due to total mutual penetrations, and their causal description via the isopoincare symmetry. The cold fusion considered is then made possible by isorenormalizations of the 'intrinsic' characteristics of particles originating from the contact-nonhamiltonian character of the internal nonlocal effects. This latter feature illustrates the reasons why the cold fusion considered is simply beyond the descriptive capacities of relativistic quantum mechanics, but it is fully predicted by its isotopic covering. 23 refs

Cold fusion labeled fiasco of century

International Nuclear Information System (INIS)

Huizenga, J.R.

1992-01-01

The gamble of researchers B. Stanley Pons and Martin Fleischmann to go public with their announcement of excess power from nuclear fusion at room temperature before they had solid evidence of fusion products is the scientific fiasco of the century, charges John R. Huizenga of the University of Rochester. He describes the claims of Pons and Fleischmann as a delusion and as pathological science. It would require belief in miracle after miracle for one to accept their discovery, he charges. Huizenga criticizes the researchers on several counts: they failed to challenge their own findings with control experiments and presentations to colleagues; they rushed to publication with unchecked and inaccurate data; they chose an unconventional method, a public press conference, to release scientific findings; their claims were not easily reproduced by others; and they lobbied Congress for funds before their claims were confirmed by independent researchers. Cold fusion producing excess power is an example of bad science where the normal rules and procedures of the scientific process were violated, Huizenga says

Bookshelf (John R. Huizenga, 'Cold Fusion: the Scientific Fiasco of the Century')

International Nuclear Information System (INIS)

Morrison, Douglas R.O.

1994-01-01

''Cold fusion is dead, isn't it?'' is a question I am often asked. The reply is a strange one, ''Yes, scientifically it is dead, but not from a media point of view or from funding'' In 1989 two electrochemists, Martin Fleischmann and Stanley Pons, claimed sustained nuclear fusion had been achieved in a test-tube with a palladium cathode and deuterium, observing excess heat, neutrons and tritium. A series of encouraging confirmations and successively greater excess heat claims were seized on by the world's media. The US Government set up a panel of some 20 world-class scientists from several disciplines under John Huizenga, distinguished professor of Chemistry and Physics at the University of Rochester. They concluded that there was no present evidence for the discovery of a new nuclear process termed cold fusion. It might be thought that would end cold fusion, but for interesting reasons, it did not entirely. John Huizenga has written a book describing the curious claims and evidence for cold fusion and has given an excellent explanation of the science involved. This was published as a hardback book of 236 pages, telling the story up to the end of June 1990. Again one might think it was the end of the cold fusion story. Now he has written about what happened in the next two years in a paperback book which contains an epilogue of 51 pages. If you thought the first year was extraordinary, the next two years described in the new edition were even more incredible! In the main part of the book, the basic science is simply and clearly explained. The number of ''miracles'' required for each results or theory is described - a ''miracle'' is a gross violation of previous knowledge and experimental results such as energy conservation. Thus some theories are classified as ''triple miracles''. It might be thought that people who claimed to have observed cold fusion

Cold fusion - no end of discussion

International Nuclear Information System (INIS)

Seifritz, W.

1991-01-01

In March 1989, Stanley Pons and Martin Fleischmann from the University of Utah/USA reported that they had discovered sporadic heat releases of non-chemical character in electro-chemical cells using palladium electrodes and heavy water. In the meantime, a series of new papers have been published in which similar effects and various explanations were described, although a number of qualified international research instituts could not confirm these findings. The subject matter 'cold fusion' is analysed critically. (orig.) [de

Conventional Physics can Explain Excess Heat in the Fleischmann-Pons Cold Fusion Effect

Science.gov (United States)

Chubb, Scott

2011-03-01

In 1989, when Fleischmann and Pons (FP) claimed they had created room temperature, nuclear fusion in a solid, a firestorm of controversy erupted. Beginning in 1991, the Office of Naval Research began a decade-long study of the FP excess heat effect. This effort documented the fact that the excess heat that FP observed is the result of a form of nuclear fusion that can occur in solids at reduced temperature, dynamically, through a deuteron (d)+d?helium-4 reaction, without high-energy particles or ? rays. This fact has been confirmed at SRI and at a number of other laboratories (most notably in the laboratory of Y. Arata, located at Osaka University, Japan). A key reason this fact has not been accepted is the lack of a cogent argument, based on fundamental physical ideas, justifying it. In the paper, this question is re-examined, based on a generalization of conventional energy band theory that applies to finite, periodic solids, in which d's are allowed to occupy wave-like, ion band states, similar to the kinds of states that electrons occupy in ordinary metals. Prior to being experimentally observed, the Ion Band State Theory of cold fusion predicted a potential d+d?helium-4 reaction, without high energy particles, would explain the excess heat, the helium-4 would be found in an unexpected place (outside heat- producing electrodes), and high-loading, x?1, in PdDx, would be required.

Fusion and reactions of exotic nuclei

Directory of Open Access Journals (Sweden)

Sánchez-Benítez A.M.

2011-10-01

Full Text Available Close to the drip lines, the scattering cross sections of halo nuclei show a different behaviour as compared to the tightly bound projectiles of the stability line. Several experiments carried out in the last decade have been dedicated to investigate the competition between transfer, breakup and fusion channels at energies around and below the Coulomb barrier. The rather complex scenario gives rise to conflicting conclusions concerning the effect of breakup and transfer on reaction dynamics and the sub-barrier fusion process. In this work we discuss recent experimental findings in fusion and reactions of 6He halo nucleus at energies around the Coulomb barrier.

Fusion enhancement in the reactions of neutron-rich nuclei

International Nuclear Information System (INIS)

Bian Baoan; Zhang Fengshou; Zhou Hongyu

2009-01-01

The neutron-rich fusion reactions are investigated systematically using the improved isospin dependent quantum molecular dynamics model. By studying the systematic dependence of fusion barrier on neuron excess, we find the enhancement of the fusion cross sections for neutron-rich nuclear reactions that give the lowered static Coulomb barriers. The calculated fusion cross sections agree quantitatively with the experimental data. We further discuss the mechanism of the fusion enhancement of the cross sections for neutron-rich nuclear reactions by analyzing the dynamical lowering of the Coulomb barrier that is attributed to the enhancement of the N/Z ratio at the neck region.

Applications of Skyrme energy-density functional to fusion reactions spanning the fusion barriers

International Nuclear Information System (INIS)

Liu Min; Wang, Ning; Li Zhuxia; Wu Xizhen; Zhao Enguang

2006-01-01

The Skyrme energy density functional has been applied to the study of heavy-ion fusion reactions. The barriers for fusion reactions are calculated by the Skyrme energy density functional with proton and neutron density distributions determined by using restricted density variational (RDV) method within the same energy density functional together with semi-classical approach known as the extended semi-classical Thomas-Fermi method. Based on the fusion barrier obtained, we propose a parametrization of the empirical barrier distribution to take into account the multi-dimensional character of real barrier and then apply it to calculate the fusion excitation functions in terms of barrier penetration concept. A large number of measured fusion excitation functions spanning the fusion barriers can be reproduced well. The competition between suppression and enhancement effects on sub-barrier fusion caused by neutron-shell-closure and excess neutron effects is studied

Reaction mechanisms for the synthesis of the heaviest elements from heavy ion reactions

International Nuclear Information System (INIS)

Gaeggeler, H.W.

1988-10-01

This review paper concerns fusion reactions with light heavy-ions, cold fusion, transfer reactions using light heavy-ions or heavy ions. In two appendices, methods for the separation and detection of nuclides in the domain of heaviest elements are described and a comment on the discovery of the element 104 is given. 51 figs., 10 tabs., 335 refs

Some experiments on cold fusion by deuterium hydrogen gas infusion in titanium metal alloy

International Nuclear Information System (INIS)

Mestnik Filho, J.; Geraldo, L.P.; Pugliese, R.; Saxena, R.N.; Morato, S.P.; Fulfaro, R.

1990-05-01

New results on cold fusion are reported where three different experimental situations have been tried: a) deuterium gas loaded titanium; b) deuterium gas loaded Ti 0.8 Zr 0.2 CrMn alloy and c) titanium and the Ti 0.8 Zr 0.2 CrMn alloy loaded with a mixture of deuterium and hydrogen gases. With these experiments, new thermodynamical non equilibrium conditions were achieved and the possibility of cold fusion between protons and deuterons was also tested. Three independent neutron detectors and one NaI(Tl) were utilized. Despite some large values reported in the literature for the fusion rate, an upper limit of only 8 x 10 -24 fusions/sper deuterium pair or per deuterium-hydrogen pair was determined within the attained accuracy. (author) [pt

Role of the press in cold fusion saga

International Nuclear Information System (INIS)

Lindley, D.

1992-01-01

Press reports of cold-fusion discoveries in Utah and the pending publication of them in Nature magazine caught the associate editor of Nature, David Lindley, by surprise. Like most people, he had never heard of cold fusion. He learned that two papers, one from Steven Jones at Brigham Young University and one from Stanley Pons and Martin Fleischmann of the University of Utah, had been submitted to Nature and were undergoing the magazine's peer-review process. For weeks, Lindley was bombarded by reporters wanting daily progress reports. Many of the reporters considered the peer review a fuddy-duddy procedure meant primarily to impose conformity and suppress revolutionary ideas. In the end, Nature decided to publish the paper by Jones but not the one by Pons and Fleischmann. Because of the doubts cast on Pons and Fleischmann's findings, Nature's decision created no great public stir, Lindley recalls. But it did help reinforce in the authors the belief that they were heretics whom the establishment was out to destroy. Like politicians struggling at the polls, they blamed everyone but themselves, Lindley says. Above all, they blaimed the two all-time favorites - the media and the establishment

The role of chain carriers in fusion reaction kinetics

International Nuclear Information System (INIS)

Harms, A.A.; Krenciglowa, E.M.

1980-01-01

The role of chain carriers as contributors to multiplicative closed cycles in advanced fusion fuels is examined. Emphasis is placed on rate processes which can be used to characterize critical/supercritical/subcritical tendencies of arbitrary closed fusion cycles. Temporal trajectories for the chain carriers which describe both increasing and decreasing multiplicative processes have been found to exist and identified according to their fusion fuel cycle characteristics. Practical criteria to ensure the attainment of steady-state fusion reaction processes have been formulated in terms of fusion reaction rate relationships. (author)

Observation of tritium in cold fusion experiments

International Nuclear Information System (INIS)

Krishnan, M.S.; Malhotra, S.K.; Gaonkar, D.G.; Sadhukhan, H.K.

1990-01-01

This paper describes the results of tritium measurements carried out during the electrolysis of heavy water in different electrolysers employing palladium and titanium as cathodes. The tritium level of electrolytes have been found to be many orders of magnitudes higher than what can be explained on the basis of isotope enrichment and evaporation during electrolysis. The neutron measurement results have also been included and these observations have been attributed to the phenomenon of cold fusion. (author). 6 refs., 1 tab

LLNL (Lawrence Livermore National Laboratory) research on cold fusion

Energy Technology Data Exchange (ETDEWEB)

Thomassen, K I; Holzrichter, J F [eds.

1989-09-14

With the appearance of reports on Cold Fusion,'' scientists at the Lawrence Livermore National Laboratory (LLNL) began a series of increasingly sophisticated experiments and calculations to explain these phenomena. These experiments can be categorized as follows: (a) simple experiments to replicate the Utah results, (b) more sophisticated experiments to place lower bounds on the generation of heat and production of nuclear products, (c) a collaboration with Texas A M University to analyze electrodes and electrolytes for fusion by-products in a cell producing 10% excess heat (we found no by-products), and (d) attempts to replicate the Frascati experiment that first found neutron bursts when high-pressure deuterium gas in a cylinder with Ti chips was temperature-cycled. We failed in categories (a) and (b) to replicate either the Pons/Fleischmann or the Jones phenomena. We have seen phenomena similar to the Frascati results, (d) but these low-level burst signals may not be coming from neutrons generated in the Ti chips. Summaries of our experiments are described in Section II, as is a theoretical effort based on cosmic ray muons to describe low-level neutron production. Details of the experimental groups' work are contained in the six appendices. At LLNL, independent teams were spontaneously formed in response to the early announcements on cold fusion. This report's format follows this organization.

Can 250+ fusions per muon be achieved?

International Nuclear Information System (INIS)

Jones, S.E.

1987-01-01

Nuclear fusion of hydrogen isotopes can be induced by negative muons (μ) in reactions such as: μ - + d + t → α + n + μ - . This reaction is analagous to the nuclear fusion reaction achieved in stars in which hydrogen isotopes (such as deuterium, d, and tritium, t) at very high temperatures first penetrate the Coulomb repulsive barrier and then fuse together to produce an alpha particle (α) and a neutron (n), releasing energy. The muon in general reappears after inducing fusion so that the reaction can be repeated many (N) times. Thus, the muon may serve as an effective catalyst for nuclear fusion. Muon-catalozed fusion is unique in that it proceeds rapidly in deuterium-tritium mixtures at relatively cold temperatures, e.g., room temperature. The need for plasma temperatures to initiate fusion is overcome by the presence of the muon

Basic study of cold fusion. 1. The development of excess heat measurement system in electrolysis

International Nuclear Information System (INIS)

Asaoka, Yoshiyuki; Fujita, Tomonari

1994-01-01

We have an opportunity ripe to investigate the cold fusion phenomena. In order to declare the subjects to be examined, the precision calorimetry system was developed to try to reproduce the phenomena. The electrolysis of heavy water with palladium cathode was conducted based on the thought that it is important to confirm the cold fusion phenomena. For precision excess power measurement, the closed cell with recombiner and flow-calorimetry were adopted. The obtained accuracy for the excess power measurement of the system was ±0.2 W at up to 9 W of applied power. This is enough for the excess power reported as the cold fusion phenomena. For farther investigation, measurement of loading ratio of deuterium in the palladium cathode, maintenance of high deuterium loading and analysis of the palladium cathode are to be conducted. (author)

Fusion reaction using low energy neutron-excess nucleus beam

International Nuclear Information System (INIS)

Fukuda, Tomokazu

1994-01-01

The present state and the plan of the experiment of measuring the fusion reaction near barriers by using neutron-excess nucleus beam, which has been advanced at RIKEN are reported. One of the purposes of this experiment is the feasibility investigation of the fusion reaction by using neutron-excess nuclei, which is indispensable for synthesizing superheavy elements. It is intended to systematically explore some enhancing mechanism in the neutron-excess nuclei which are unfavorable in beam intensity. This research can become the good means to prove the dynamic behavior of the neutrons on the surfaces of nuclei in reaction. The fusion reaction of 27 Al + Au was measured by using the stable nucleus beam of 27 Al, and the results are shown. In order to know the low energy fusion reaction of 11 Li and 11 Be which are typical halo nuclei, the identification by characteristic α ray of composite nuclei is carried out in 7,9,11 Li + 209 Bi and 9,10,11 Be + 208 Pb. A new detector having high performance, New MUSIC, is being developed. As the experiment by using this detector, the efficient measurement of the fusion reaction by using heavy neutron-excess nuclei up to Ni is considered. An example of 8 Li + α → 11 B + n reaction for celestial body physics is mentioned. (K.I.)

How does the carbon fusion reaction happen in stars?

International Nuclear Information System (INIS)

Tang, X.; Bucher, B.; Fang, X.; Notani, M.; Tan, W.P.; Mooney, P.; Li, Y.; Esbensen, H.; Jiang, C.L.; Rehm, K.E.; Lin, C.J; Brown, E.

2012-01-01

The 12 C + 12 C fusion reaction is one of the most important reactions in the stellar evolution. Due to its complicated reaction mechanism, there is great uncertainty in the reaction rate which limits our understanding of various stellar objects, such as massive stellar evolution, explosions on neutron stars, and supernovae from accreting white dwarf stars. In this paper, I will review the challenges in the study of carbon burning. I will also report recent results from our studies: 1) an upper limit for the 12 C + 12 C fusion cross sections, 2) measurement of the 12 C + 12 C at deep sub-barrier energies, and 3) a new measurement of the 12 C( 12 C, n) reaction. The outlook for the studies of the astrophysical heavy-ion fusion reactions will also be presented

Fusion Reactions and Matter-Antimatter Annihilation for Space Propulsion

Science.gov (United States)

2005-07-13

FUSION REACTIONS AND MATTER- ANTIMATTER ANNIHILATION FOR SPACE PROPULSION Claude DEUTSCH LPGP (UMR-CNRS 8578), Bât. 210, UPS, 91405 Orsay...REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE šFusion Reactions And Matter- Antimatter Annihilation For Space Propulsion 5a...which is possible with successful MCF or ICF. Appropriate vessel designs will be presented for fusion as well as for antimatter propulsion. In

Cold fusion, mass media and actual science

Energy Technology Data Exchange (ETDEWEB)

Orefice, A. (Milan Univ. (Italy))

1990-03-01

The peculiar affair of cold nuclear fusion, a recent and exemplary pattern of today's scientific and public habits, is considered. An overview is proposed on the contemporary approach to science and technology, both of the mass media and research worlds. It shows how mass media with its power of suggestion and ability to raise financial resources can lead many researchers into unpredictable - if not irresponsible behaviour. Yet, an eccess of empiricism may often induce researchers to rely rather on serendipity than on deeper meditation.

Study of fusion reactions forming Cf nuclei

International Nuclear Information System (INIS)

Khuyagbaatar, J.; Hinde, D. J.; Du Rietz, R.; Carter, I. P.; Dasgupta, M.; Duellmann, C. E.; Evers, M.; Wakhle, A.; Williams, E.; Yakushev, A.

2013-01-01

The formation of a compound nucleus in different projectile and target combinations is a powerful method for investigating the fusion process. Recently, the dominance of quasi-fission over fusion-fission has been inferred for 34 S+ 208 Pb in comparison to 36 S+ 206 Pb; both reactions lead to the compound nucleus 242 Cf*.The mass and angle distributions of the fission fragments from these reactions were studied in order to further investigate the presence of quasi-fission. (authors)

How does the carbon fusion reaction happen in stars?

Directory of Open Access Journals (Sweden)

X. Tang

2013-09-01

Full Text Available The 12C + 12C fusion reaction is one of the most important reactions in the stellar evolution. Due to its compli-cated reaction mechanism, there is great uncertainty in the reaction rate which limits our understanding of vari-ous stellar objects, such as explosions on the surface of neutron stars, white dwarf (type Ia supernovae, and massive stellar evolution. In this paper, I will review the challenges in the study of carbon burning. I will also report recent re-sults from our studies: 1 an upper limit for the 12C + 12C fusion cross sections, 2 measurement of the 12C + 12C at deep sub-barrier energies, 3 a new measurement of the 12C(12C, n reaction. The outlook for the studies of the astrophysical heavy-ion fusion reactions will also be presented.

Subsequent development of the normal temperature fusion reaction. Joon kakuyugo sonogo no shinten

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, T. (Hokkaido University, Sapporo (Japan). Faculty of Engineering)

1991-04-24

This paper reports on a NATTOH model made public in May 1989 by T. Matsumoto who took notice of abnormality of the normal temperature fusion reaction. The NATTO model is based on a chain reaction by hydrogen with a hydrogen-catalyzed fusion reaction which is the normal temperature fusion reaction as an elementary process. If a high temperature fusion reaction is a small-size simulation of the fusion reaction rising on the surface of the sparkling star like the sun, the normal temperature fusion reaction can be a small-size simulation of the phenomena in the last years of the star in the far distance of the space. This gives reality to the normal temperature fusion reaction. The reaction mechanism of the normal temperature fusion reaction is almost being clarified by a NATTOH model. There remain problems on a possibility of generation of unknown radioactive rays and identification of radioactive wastes, but it seems that a prospect of commercialization can be talked about now. As for the utilization as energy, sea water may be used as it is. 10 ref., 5 figs.

Neutron detector for fusion reaction-rate measurements

International Nuclear Information System (INIS)

Lerche, R.A.; Phillion, D.W.; Tietbohl, G.L.

1993-01-01

We have developed a fast, sensitive neutron detector for recording the fusion reaction-rate history of inertial-confinement fusion (ICF) experiments. The detector is based on the fast rise-time of a commercial plastic scintillator (BC-422) and has a response 7 neutrons

Biases in cold fusion data; and reply

International Nuclear Information System (INIS)

Freedman, Stuart; Krakauer, Daniel; Jones, S.E.; Decker, D.L.; Tolley, H.D.

1990-01-01

These two letters represent a criticism of a claim to have observed ''cold'' nuclear fusion and the original scientists' rebuttal of the claims against them. The first authors suggest that data presented has a peculiar characteristic, which, they claim, indicates a systematic bias in the data collection process, and thus calls the claimed observation into dispute. In reply, the original workers list a huge range of checks they made, before and after receiving the criticism, making allowances for all sorts of external parameters capable of affecting their results. (UK)

The cross sections of fusion-evaporation reactions: the most promising route to superheavy elements beyond Z=118

Science.gov (United States)

Jadambaa, Khuyagbaatar

2017-11-01

The synthesis of superheavy elements beyond oganesson (Og), which has atomic number Z = 118, is currently one of the main topics in nuclear physics. An absence of sufficient amounts of target material with atomic numbers heavier than californium (Z = 98) forces the use of projectiles heavier than 48Ca (Z = 20), which has been successfully used for the discoveries of elements with Z = 114 - 118 in complete fusion reactions. Experimental cross sections of 48Ca with actinide targets behave very differently to "cold" and "hot" fusion-evaporation reactions, where doubly-magic lead and deformed actinides are used as targets, respectively. The known cross sections of these reactions have been analysed compared to calculated fission barriers. It has been suggested that observed discrepancies between the cross sections of 48Ca-induced and other fusionevaporation reactions originate from the shell structure of the compound nucleus, which lies in the island of the stability. Besides scarcely known data on other reactions involving heavier projectiles, the most promising projectile for the synthesis of the elements beyond Og seems to be 50Ti. However, detailed studies of 50Ti, 54Cr, 58Fe and 64Ni-induced reactions are necessary to be performed in order to fully understand the complexities of superheavy element formation.

Social Aspects of Cold Fusion: 23 Years Later

Directory of Open Access Journals (Sweden)

Kowalski L.

2012-04-01

Full Text Available The field of Cold Fusion, now called Condensed Matter Nuclear Science (CMNS, re- mains controversial. The original 1989 claim made by M. Fleischmann and S. Pons was that a chemical process in an electrolytic cell could initiate a nuclear reaction–fusion of two deuterium nuclei. More recent CMNS claims, made by experimental scientists, are: emission of charged nuclear projectiles during electrolysis; accumulation of 4 He; production of radioactive isotopes; and transmutation of elements. In the US, CMNS claims have been evaluated in two Department of Energy (DOE investigations, in 1989 and 2004, as summarized in this article. These investigations did not lead to any resolu- tion of the controversy. Scientists and adminstrators are not ideal; competition among them, as among other groups of people, tends to have both positive and negative influ- ences.

Search for evidence of nuclear involvement in the fatal explosion of a 'cold fusion' experiment

International Nuclear Information System (INIS)

Grant, P.M.; Whipple, R.E.; Andresen, B.D.; Russo, R.E.; Bazan, F.; Brunk, J.L.; Wong, K.M.

1995-01-01

Forensic analyses of debris from the fatal explosion of an electrochemical 'cold fusion' cell at SRI International were conducted at LLNL at the request of Cal-OSHA. One investigation focused on the possibility of conventional nuclear reaction mechanisms contributing to the total energy inventory of the incident. Selected metal components of the electrolysis apparatus were subjected to nondestructive γ-ray spectrometry with high-sensitivity, low-background Ge detector systems. The anticipated analytes in these studies were radioactivation products potentially induced in the explosion residue by either fast or thermal neutrons. The results of this investigation were negative within the temporal constraints of the incident and the analytical sensitivities of the instrumentation. (author) 5 refs.; 1 fig.; 2 tabs

Cluster expression in fission and fusion in high-dimensional macroscopic-microscopic calculations

International Nuclear Information System (INIS)

Iwamoto, Akira; Ichikawa, Takatoshi; Moller, Peter; Sierk, Arnold J.

2004-01-01

We discuss the relation between the fission-fusion potential-energy surfaces of very heavy nuclei and the formation process of these nuclei in cold-fusion reactions. In the potential-energy surfaces, we find a pronounced valley structure, with one valley corresponding to the cold-fusion reaction, the other to fission. As the touching point is approached in the cold-fusion entrance channel, an instability towards dynamical deformation of the projectile occurs, which enhances the fusion cross section. These two 'cluster effects' enhance the production of superheavy nuclei in cold-fusion reactions, in addition to the effect of the low compound-system excitation energy in these reactions. Heavy-ion fusion reactions have been used extensively to synthesize heavy elements beyond actinide nuclei. In order to proceed further in this direction, we need to understand the formation process more precisely, not just the decay process. The dynamics of the formation process are considerably more complex than the dynamics necessary to interpret the spontaneous-fission decay of heavy elements. However, before implementing a full dynamical description it is useful to understand the basic properties of the potential-energy landscape encountered in the initial stages of the collision. The collision process and entrance-channel landscape can conveniently be separated into two parts, namely the early-stage separated system before touching and the late-stage composite system after touching. The transition between these two stages is particularly important, but not very well understood until now. To understand better the transition between the two stages we analyze here in detail the potential energy landscape or 'collision surface' of the system both outside and inside the touching configuration of the target and projectile. In Sec. 2, we discuss calculated five-dimensional potential-energy landscapes inside touching and identify major features. In Sec. 3, we present calculated

Selected aspects of fusion reactions

International Nuclear Information System (INIS)

Lacroix, D.

2003-01-01

In this lecture, we present selected aspects of nuclear fusion. The importance of the initial geometry of the reaction and its relation to fusion barrier are first discussed. The effect of deformation leading to the notion of barrier distribution is then illustrated. After a brief overview of the advantages of macroscopic theories, the dynamics of nuclear system under large amplitude motion is reviewed. The di-nuclear concept is presented to understand the competition between fusion and quasi-fission. This concept is then generalized to account for the dissipative dynamics in multidimensional collective space. The last part of this lecture is devoted to new aspects encountered with radioactive beams specific properties of very extended neutron rich system, influence of pygmy or soft dipole resonances and charge exchange far from stability are discussed. (author)

Cold-cap reactions in vitrification of nuclear waste glass: experiments and modeling

International Nuclear Information System (INIS)

Chun, Jaehun; Pierce, David A.; Pokorny, Richard; Hrma, Pavel R.

2013-01-01

Cold-cap reactions are multiple overlapping reactions that occur in the waste-glass melter during the vitrification process when the melter feed is being converted to molten glass. In this study, we used differential scanning calorimetry (DSC) to investigate cold-cap reactions in a high-alumina high-level waste melter feed. To separate the reaction heat from both sensible heat and experimental instability, we employed the run/rerun method, which enabled us to define the degree of conversion based on the reaction heat and to estimate the heat capacity of the reacting feed. Assuming that the reactions are nearly independent and can be approximated by the nth order kinetics, we obtained the kinetic parameters using the Kissinger method combined with least squares analysis. The resulting mathematical simulation of the cold-cap reactions provides a key element for the development of an advanced cold-cap model

Lenr and "cold Fusion" Excess Heat:. Their Relation to Other Anomalous Microphysical Energy Experiments and Emerging New Energy Technologies

Science.gov (United States)

Mallove, Eugene F.

2005-12-01

During the past 15 years, indisputable experimental evidence has built up for substantial excess heat (far beyond ordinary chemical energy) and low-energy nuclear reaction phenomena in specialized heavy hydrogen and ordinary hydrogen-containing systems.1 The primary theorists in the field that is properly designated Cold Fusion/LENR have generally assumed that the excess heat phenomena is commensurate with nuclear ash (such as helium), whether already identified or presumed to be present but not yet found. That was an excellent initial hypothesis. However, the commensurate nuclear ash hypothesis has not been proved, and appears to be approximately correct in only a few experiments. During this same period, compelling evidence although not as broadly verified as data from cold fusion/LENR has also emerged for other microphysical sources of energy that were previously unexpected by accepted physics. The exemplar of this has been the "hydrino" physics work of Dr. Randall Mills and his colleagues at Black-Light Power Corporation, which was a radical outgrowth from the cold fusion field that emerged publicly in May 1991.2 Even more far-reaching is the work in vacuum energy extraction pioneered by Dr. Paulo and Alexandra Correa, which first became public in 1996.3 This vacuum energy experimentation began in the early 1980s and has been reduced to prototype technological devices, such as the patented PAGDTM (pulsed abnormal glow discharge) electric power generator, as well as many published experiments that can be performed in table-top fashion to verify the Correa Aetherometry (non-luminiferous or non-electromagnetic aether measurement science).4 In an era when mainstream science and its media is all agog about dark matter and dark energy composing the vast bulk of the universe, there is a great need to reconcile, if possible, the significant bodies of evidence from these three major experimental and theoretical streams: cold fusion/LENR, hydrino physics, and

Experimental studies on cold fusion and hydrogen-metal

International Nuclear Information System (INIS)

Locou, P.

2007-01-01

The cold fusion is a nuclear fusion realized in pervading conditions of temperature and pressure. My own process is parallel to that of the team of the University of Los Angeles, but shaped in 1996 within my personal and private Laboratory: A small cylinder in which we replace the air by some deuterium to the gas state in - 33 d egree (the deuterium is some hydrogen with a neutron, which we find in quantity in the sea water). We introduce a crystal there, extremely rare - the property of which is to emit continuously one thousand times dose of successful energy and it during several years without outside pyro, natural excitement - electric - that is it creates an electric field in the slightest change in temperature. We carry then the whole in + 7 d egree, what generates in some seconds a 200 000 volt electric field, an intense enough field to separate the pits of the deuterium of their electrons and to admit them to collide with those of the crystal. There is a fusion of protons between them (positive particles of the pit (core)) and a emission of neutrons, which do not merge. It is this emission which serves for measuring the quantity of energy produced by the fusion (merger). We so managed to produce some energy in unlimited quantity, allowing us to feed our installation with electric current in total autarky, and to reduce so our costs of functioning to divers domains. This crystal is exceptional in its applications and to give it the name would return has to break our current headway: the thorough problem, in this current period of takeover by the financial bodies of the possible patents, brought to us to the biggest caution as regards our results. And, as we look for no outside financing, we do not need to submit ourselves to the requirements lauded by the scientific Community, only our results are strictly estimated. For example we can make estimate our bars or patches of Hydrogen - Metal: a simple spectroscopy in YEW will give as result, only, the element H

Fusion reaction product diagnostics in ASDEX

International Nuclear Information System (INIS)

Bosch, H.S.

1987-01-01

A diagnostic method was developed to look for the charged fusion products from the D(D,p)T-reactions in the divertor tokamak ASDEX. With a semi-conductor detector it was possible to evaluate the ion temperature in thermal plasmas from the proton energy spectra as well as from the triton spectra. In lower-hybrid wave heated plasmas non-thermal (fast) ions were observed. These ions create fusion products with a characteristically different energy spectrum. (orig.)

First dedicated in-beam X-ray measurement in heavy-ion fusion reactions

Energy Technology Data Exchange (ETDEWEB)

Berner, C. [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); RIKEN, Research Group for Superheavy Elements (Japan); Henning, W. [Argonne National Laboratory, Physics Division (United States); RIKEN, Research Group for Superheavy Elements (Japan); Muecher, D.; Gernhaeuser, R.; Hellgartner, S.; Maier, L. [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); Morita, K.; Morimoto, K.; Kaji, D.; Wakabayashi, Y.; Baba, H. [RIKEN, Research Group for Superheavy Elements (Japan); Lutter, R. [Ludwig-Maximilians-Universitaet, Muenchen (Germany)

2016-07-01

We report on an experiment aiming at in-beam X-ray spectroscopy of heavy and superheavy elements (SHE). The goal is to establish K-X-ray spectroscopy as a sensitive tool to identify SHE produced in fusion reactions. SHE, formed after cold or hot fusion, are usually identified via the alpha-decay products, which have to be connected to well-known elements. However, various theories predict spontaneous fission as the dominant decay mode for the daughter nuclides. Additionally, half-lives of these elements are expected to increase to values impeding the identification of SHE solely by their decay. The in-beam identification of the characteristic X-rays would precisely allow to identify the charge number of the produced SHE. Experiments were performed at the RIKEN Nishina Centre for Accelerator based Science by using the gas-filled magnet separator GARIS for superheavy element detection. A high-purity, low-energy planar germanium LEGe-detector was adapted to the GARIS system at the target place for the first time in order to measure the element-characteristic, prompt X-ray emission.

Effects of reaction channels in subbarrier fusion reactions

International Nuclear Information System (INIS)

Dasso, C.H.

1984-01-01

In this lecture we consider some aspects of fusion reactions between heavy ions at bombarding energies which are below or close to that of the Coulomb barrier. This problem has been traditionally confronted with simple barrier penetration calculations. So we start with a very brief review of what we can call the ''conventional'' procedure. (orig.)

Screening effects on 12C+12C fusion reaction

Science.gov (United States)

Koyuncu, F.; Soylu, A.

2018-05-01

One of the important reactions for nucleosynthesis in the carbon burning phase in high-mass stars is the 12C+12C fusion reaction. In this study, we investigate the influences of the nuclear potentials and screening effect on astrophysically interesting 12C+12C fusion reaction observables at sub-barrier energies by using the microscopic α–α double folding cluster (DFC) potential and the proximity potential. In order to model the screening effects on the experimental data, a more general exponential cosine screened Coulomb (MGECSC) potential including Debye and quantum plasma cases has been considered in the calculations for the 12C+12C fusion reaction. In the calculations of the reaction observables, the semi-classical Wentzel-Kramers-Brillouin (WKB) approach and coupled channel (CC) formalism have been used. Moreover, in order to investigate how the potentials between 12C nuclei produce molecular cluster states of 24Mg, the normalized resonant energy states of 24Mg cluster bands have been calculated for the DFC potential. By analyzing the results produced from the fusion of 12C+12C, it is found that taking into account the screening effects in terms of MGECSC is important for explaining the 12C+12C fusion data, and the microscopic DFC potential is better than the proximity potential in explaining the experimental data, also considering that clustering is dominant for the structure of the 24Mg nucleus. Supported by the Turkish Science and Research Council (TÜBİTAK) with (117R015)

A view on reactions of complete fusion

International Nuclear Information System (INIS)

Delchev, I.I.; Petkov, I.J.

1978-11-01

Complete fusion reactions are analysed within the framework of a theoretical model. Energy density interaction potentials are made use of and are renormalized for the purpose. A large number of heavy ion reactions are studied and the calculated critical angular moments are compared with experimental data

Design of a fusion reaction-history measurement system with high temporal resolution

International Nuclear Information System (INIS)

Peng Xiaoshi; Wang Feng; Liu Shenye; Jiang Xiaohua; Tang Qi

2010-01-01

In order to accurately measure the history of fusion reaction for experimental study of inertial confinement fusion, we advance the design of a fusion reaction-history measurement system with high temporal resolution. The diagnostic system is composed of plastic scintillator and nose cone, an optical imaging system and the system of optic streak camera. Analyzing the capability of the system indicated that the instrument measured fusion reaction history at temporal resolution as low as 55ps and 40ps correspond to 2.45MeV DD neutrons and 14.03MeV DT neutrons. The instrument is able to measure the fusion reaction history at yields 1.5 x 10 9 DD neutrons, about 4 x 10 8 DT neutrons are required for a similar quality signal. (authors)

Plasma nuclear fusion method

International Nuclear Information System (INIS)

Yamazaki, Shunpei; Miyanaga, Shoji; Wakaizumi, Kazuhiro; Takemura, Yasuhiko.

1990-01-01

Nuclear fusion reactions are attained by plasma gas phase reactions using magnetic fields and microwaves, and the degree of the reactions is controlled. That is, deuterium (D 2 ) is introduced into a plasma container by utilizing the resonance of microwaves capable of generating plasmas at high density higher by more than 10 - 10 3 times as compared with the high frequency and magnetic fields, and an electric energy is applied to convert gaseous D 2 into plasmas and nuclear fusion is conducted. Further, the deuterium ions in the plasmas are attracted to a surface of a material causing nuclear fusion under a negatively biased electric field from the outside (typically represented by Pd or Ti). Then, deuterium nuclei (d) or deuterium ions collide to the surface of the cathode on the side of palladium to conduct nuclear reaction at the surface or the inside (vicinity) thereof. However, a DC bias is applied as an external bias with the side of the palladium being negative. The cold nuclear fusion was demonstrated by placing a neutron counter in the vicinity of the container and confirming neutrons generated there. (I.S.)

Recent developments in heavy-ion fusion reactions around the Coulomb barrier

Directory of Open Access Journals (Sweden)

Hagino K.

2016-01-01

Full Text Available The nuclear fusion is a reaction to form a compound nucleus. It plays an important role in several circumstances in nuclear physics as well as in nuclear astrophysics, such as synthesis of superheavy elements and nucleosynthesis in stars. Here we discuss two recent theoretical developments in heavy-ion fusion reactions at energies around the Coulomb barrier. The first topic is a generalization of the Wong formula for fusion cross sections in a single-channel problem. By introducing an energy dependence to the barrier parameters, we show that the generalized formula leads to results practically indistinguishable from a full quantal calculation, even for light symmetric systems such as 12C+12C, for which fusion cross sections show an oscillatory behavior. We then discuss a semi-microscopic modeling of heavy-ion fusion reactions, which combine the coupled-channels approach to the state-of-the-art nuclear structure calculations for low-lying collective motions. We apply this method to subbarrier fusion reactions of 58Ni+58Ni and 40Ca+58Ni systems, and discuss the role of anharmonicity of the low-lying vibrational motions.

Microscopic study on dynamic barrier in fusion reactions

International Nuclear Information System (INIS)

Wu Xizhen; Tian Junlong; Zhao Kai; Li Zhuxia; Wang Ning

2004-01-01

The authors briefly review the fusion process of very heavy nuclear systems and some theoretical models. The authors propose a microscopic transport dynamic model, i.e. the Improved Quantum Molecular Dynamic model, for describing fusion reactions of heavy systems, in which the dynamical behavior of the fusion barrier in heavy fusion systems has been studied firstly. The authors find that with the incident energy decreasing the lowest dynamic barrier is obtained which approaches to the adiabatic static barrier and with increase of the incident energy the dynamic barrier goes up to the diabatic static barrier. The authors also indicate that how the dynamical fusion barrier is correlated with the development of the configuration of fusion partners along the fusion path. Associating the single-particle potentials obtained at different stages of fusion with the Two Center Shell Model, authors can study the time evolution of the single particle states of fusion system in configuration space of single particle orbits along the fusion path. (author)

Cold fusion in the context of a scientific revolution in physics: History and economic ramifications

International Nuclear Information System (INIS)

Lewis, Edward

2006-01-01

Scientific revolutions have occurred in an approximately 80 year periodicity since 1500. Economic depressions have occurred at an approximately 40-50 year periodicity since 1790, and the economic depressions are a result of the scientific revolutions. The field of cold fusion is a part of a scientific revolution in physics. Understanding cold fusion phenomena in the broader historical context is helpful for understanding the development of the field and the significance of the phenomena technologically and economically. This paper includes a short history of science and of the recent scientific revolution, and includes predictions about the economic consequences of the development of the paradigm. (author)

Detailed determination of the fusion nuclear radius in reactions involving weakly bound projectiles

International Nuclear Information System (INIS)

Gomez Camacho, A.; Aguilera, E. F.; Quiroz, E. M.

2007-01-01

A detailed determination of the fusion radius parameter is performed within the Distorted Wave Born Approximation for reactions involving weakly bound projectiles. Specifically, a simultaneous X 2- analysis of elastic and fusion cross section data is done using a Woods-Saxon potential with volume and surface parts. The volume part is assumed to be responsible for fusion reactions while the surface part for all other direct reactions. It is proved that in order to fit fusion data, particularly for energies below the Coulomb barrier where fusion is enhanced, it is necessary to have a value of around 1.4 fm for the fusion radial parameter of the fusion potential (W F ). This value is much higher than that frequently used in Barrier Penetration models (1.0 fm). The calculations are performed for reactions involving the weakly bound projectile 9 Be with several medium mass targets. (Author)

Quasi-elastic scattering an alternative tool for mapping the fusion barriers for heavy-ion induced fusion reaction

International Nuclear Information System (INIS)

Behera, B.R.

2016-01-01

Heavy element synthesis through heavy-ion induced fusion reaction is an active field in contemporary nuclear physics. Exact knowledge of fusion barrier is one of the essential parameters for planning any experiments for heavy element production. Theoretically there are many models available to predict the exact barrier. Though these models are successful for predicting the fusion of medium mass nuclei, it somehow fails for predicting the exact location of barrier for fusion of heavy nuclei. Experimental determination of barrier for such reactions is required for future experiments for the synthesis of heavy elements. Traditionally fusion barrier is determined taking a double derivative of fusion excitation function. However, such method is difficult in case of fusion of heavy nuclei due to its very low fusion/capture cross section and its experimental complications. Alternatively fusion barrier can be determined by measuring the quasi-elastic cross section at backward angles. This method can be applied for determining the fusion barrier for the fusion of heavy nuclei. Experimental determination of fusion barrier by different methods and comparison of the fusion excitation function and quasi-elastic scattering methods for the determination of fusion barrier are reviewed. At IUAC, New Delhi recently a program has been started for the measurement of fusion barrier through quasi-elastic scattering methods. The experimental facility and the first results of the experiments carried out with this facility are presented. (author)

Fusion dynamics in 40Ca induced reactions

International Nuclear Information System (INIS)

Prasad, E.; Hinde, D.J.; Williams, E.

2017-01-01

Synthesis of superheavy elements (SHEs) and investigation of their properties are among the most challenging research topics in modern science. A non-compound nuclear process called quasi fission is partly responsible for the very low production cross sections of SHEs. The formation and survival probabilities of the compound nucleus (CN) strongly depend on the competition between fusion and quasi fission. A clear understanding of these processes and their dynamics is required to make reliable predictions of the best reactions to synthesise new SHEs. All elements beyond Nh are produced using hot fusion reactions and beams of 48 Ca were used in most of these experiments. In this context a series of fission measurements have been carried out at the Australian National University (ANU) using 40;48 Ca beams on various targets ranging from 142 Nd to 249 Cf. Some of the 40 Ca reactions will be discussed in this symposium

Recent developments in fusion and direct reactions with weakly bound nuclei

International Nuclear Information System (INIS)

Canto, L.F.; Gomes, P.R.S.; Donangelo, R.; Lubian, J.; Hussein, M.S.

2015-01-01

In this Report we give a balanced account of the experimental and theoretical advances acquired over the last decade in the field of near-barrier fusion reactions induced by weakly bound stable and unstable nuclei. The elastic scattering and breakup reactions of these systems are also extensively reviewed as they play an important role in the fusion process. We review several theoretical tools used in the description of the data. The concepts of Complete Fusion (CF), Incomplete Fusion (ICF) and Total Fusion (TF), which is the sum of CF and ICF, are discussed and recent work on the calculation of these quantities is reviewed. The Continuum Discretized Coupled Channels (CDCC) method and its semiclassical version are described in detail and their limitations are pointed out. More importantly, we describe the salient features of the conclusions reached from the more than 40 measurements made, over a decade, of near-barrier fusion, elastic scattering and breakup reactions, and confront these data with the CDCC or other methods appropriate for these processes at the energy regime in question.

Nuclear Waste Vitrification Efficiency: Cold Cap Reactions

International Nuclear Information System (INIS)

Kruger, A.A.; Hrma, P.R.; Pokorny, R.

2011-01-01

The cost and schedule of nuclear waste treatment and immobilization are greatly affected by the rate of glass production. Various factors influence the performance of a waste-glass melter. One of the most significant, and also one of the least understood, is the process of batch melting. Studies are being conducted to gain fundamental understanding of the batch reactions, particularly those that influence the rate of melting, and models are being developed to link batch makeup and melter operation to the melting rate. Batch melting takes place within the cold cap, i.e., a batch layer floating on the surface of molten glass. The conversion of batch to glass consists of various chemical reactions, phase transitions, and diffusion-controlled processes. These include water evaporation (slurry feed contains as high as 60% water), gas evolution, the melting of salts, the formation of borate melt, reactions of borate melt with molten salts and with amorphous oxides (Fe 2 O 3 and Al 2 O 3 ), the formation of intermediate crystalline phases, the formation of a continuous glass-forming melt, the growth and collapse of primary foam, and the dissolution of residual solids. To this list we also need to add the formation of secondary foam that originates from molten glass but accumulates on the bottom of the cold cap. This study presents relevant data obtained for a high-level-waste melter feed and introduces a one-dimensional (1D) mathematical model of the cold cap as a step toward an advanced three-dimensional (3D) version for a complete model of the waste glass melter. The 1D model describes the batch-to-glass conversion within the cold cap as it progresses in a vertical direction. With constitutive equations and key parameters based on measured data, and simplified boundary conditions on the cold-cap interfaces with the glass melt and the plenum space of the melter, the model provides sensitivity analysis of the response of the cold cap to the batch makeup and melter

Effect of projectile structure on evaporation residue yields in incomplete fusion reactions

CERN Document Server

Babu, K S; Sudarshan, K; Shrivastava, B D; Goswami, A; Tomar, B S

2003-01-01

The excitation functions of heavy residues, representing complete and incomplete fusion products, produced in the reaction of sup 1 sup 2 C and sup 1 sup 3 C on sup 1 sup 8 sup 1 Ta have been measured over the projectile energy range of 5 to 6.5 MeV/nucleon by the recoil catcher method and off-line gamma-ray spectrometry. Comparison of the measured excitation functions with those calculated using the PACE2 code based on the statistical model revealed the occurrence of incomplete fusion reactions in the formation of alpha emission products. The fraction of incomplete fusion cross sections in the sup 1 sup 2 C + sup 1 sup 8 sup 1 Ta reaction was found to be higher, by a factor of approx 2, than that in the sup 1 sup 3 C + sup 1 sup 8 sup 1 Ta reaction. The results have been discussed in terms of the effect of alpha cluster structure of the projectile on incomplete fusion reactions.

Plasma fluctuations and confinement of fusion reaction products

International Nuclear Information System (INIS)

Coppi, B.; Pegoraro, F.

1981-01-01

The interaction between the fluctuations that can be excited in a magnetically confined plasma and the high-energy-particle population produced by fusion reactions is analyzed in view of its relevance to the process of thermonuclear ignition. The spectrum of the perturbations that, in the absence of fusion reaction products, would be described by the incompressible ideal magnetohydrodynamic approximation is studied considering finite value of the plasma pressure relative ot the magnetic pressure. The combined effects of the magnetic field curvature and shear are taken into account and the relevant spectrum is shown to consist of a continuous portion, that could be identified as a mixture of shear-Alfven and interchange oscillations, and a discrete unstable part corresponding to the so-called ballooning modes. The rate of diffusion of the fusion reaction products induced by oscillations in the continuous part of the spectrum, as estimated from the appropriate quasi-linear theory, is found to be significantly smaller than could be expected if normal modes (i.e., nonconvective solutions) were excited. However, a relatively wide intermediate region is identified where opalescent fluctuations, capable of achieving significant amplitudes and corresponding to a quasi-discrete spectrum, can be excited

Prediction of new tightly bound-states of H2+(d2+) and ''cold fusion''-experiments

International Nuclear Information System (INIS)

Barut, A.O.

1989-06-01

It is suggested that in the ''cold-fusion'' experiments of Fleischmann and Pons new tightly-bound molecular states of D 2 + are formed with binding energies predicted to be of the order of 50 keV accounting for the heat released without appreciable fusion. Other tests of the suggested mechanism are proposed and the derivation of the new energy levels is given. (author). 3 refs

Cold fusion 1: the discovery that never was

International Nuclear Information System (INIS)

Close, F.

1991-01-01

In this first of two articles chronicalling the claims to have produced ''cold fusion'' in 1989, the author, a nuclear physicist, explores the evidence against the claim. A brief description is offered of the experimental work that led to the claim and a critique of research methods and lack of proper scientific procedures is offered. The work of many reputable scientific teams across the globe, especially that done at Harwell Laboratory, to replicate the results produced negative results. The author suggests that what positive results exist, subsequent to the original claim, are anecdotal and done by less professionally qualified workers, and can consequently be dismissed. (UK)

Observations on the biological cold fusion or the biological transmutation of elements

International Nuclear Information System (INIS)

Komaki, Hisatoki

1993-01-01

In previous paper, the author, with Prof. Dr. C. Louis KERVRAN, suggested the probable occurrence of the biological cold fusion or the biological transmutation of elements. In order to confirm the phenomena, under the more controlled condition, potassium, magnesium, iron and calcium were determined in cells of Aspergillus niger IFO 4066, Penicillium chrysogenum IFO 4689, Rhizopus nigricans IFO 5781, Mucor rouxii IFO 0396, Saccharomyces cerevisiae IFO 0308, Torulopsis utilis IFO 0396, Saccharomyces ellipsoideus IFO 0213 and Hansenula anomala IFO 0118 cultured in normal medium and media deficient in one of potassium, magnesium iron or calcium. Values of potassium 1890-2650 μg, magnesium 380-510 μg, iron 95-120 μg, and calcium 60-95 μg were obtained per g dried cells cultured in each deficient medium, while potassium 8650-11050 μg, magnesium 1920-2160 μg, iron 510-680 μg, and calcium 380-450 μg were found per g dried cells obtained by cultivation in the normal medium. The author would like to suggest the probable occurrence of the phenomena relevant to biological cold fusion. (author)

Fusion reaction around the Coulomb barrier with neutron-rich nuclei

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Atsushi [Institute of Physical and Chemical Research, Wako, Saitama (Japan)

1997-07-01

Two fusion reactions with neutron-rich nuclei are reported in this work. On the first reaction: {sup 9,10,11}Be+{sup 209}Bi, the fusion cross sections around the coulomb barrier were measured by determing {alpha} disintegration from compound nucleus Fr. In the field of 10-100 mb, the same total fusion cross sections were obtained. The phenomenon {sup 11}Be(neutron halo nucleus) alone increased and decreased was not observed. The fusion cross sections of {sup 27,29,31}Al+{sup 197}Au system were determined by using 130 kcps and 30 kcps of beam strength of {sup 29,31}Al, respectively. The value of {sup 27}Al was reproduced by calculation, but that of {sup 29}Al increased around barrier which could not be explained by CCDEF calculation. (S.Y.)

Many-body treatment of subbarrier fusion reactions

Energy Technology Data Exchange (ETDEWEB)

Iwamoto, Akira; Kondratyev, V. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Bonasera, A.

1998-07-01

The subbarrier fusion of heavy-ions at energies around the Coulomb barrier is studied by using semiclassical mean-field theory. The paths connecting entrance and exit subbarrier fusion reaction channels are found by incorporating the Wick transformation into the mean-field kinetic equation. The polarization and deformation of nuclei is shown to lower the barrier height. It is demonstrated that preequilibrium nucleon exchange in classically forbidden region gives rise to the nonlocal effects lowering the effective barrier further at small relative distance. (author)

Fusion barrier distributions in 28,30Si + 124Sn reactions

International Nuclear Information System (INIS)

Danu, L.S.; Nayak, B.K.; Biswas, D.C.; Saxena, A.; Thomas, R.G.; Mirgule, E.T.; Choudhury, R.K.

2009-01-01

The coupling of various degrees of freedom such as static deformation, inelastic excitation and nucleon transfer with the relative motion gives rise to a distribution of barrier in heavy ion induced fusion reactions. The barrier distribution is a fingerprint of the reaction characterizing the important channel couplings. The relative importance of various couplings in fusion reaction is of topical interest. In an earlier study with deformed projectiles 28,30 Si on 115 In target, it was observed that the barrier distributions get affected due to coulomb reorientation of the deformed projectile nuclei in the field of target nucleus thus giving rise to fusion hindrance at sub-barrier energies. In that study, we considered deformed projectile rotational and positive Q-value transfer channel couplings to relative motion in fusion for investigation of Coulomb reorientation and no inelastic coupling of the 115 In target was considered. In the present work, we have extended the measurements with 124 Sn target and inelastic coupling of target has been considered in the coupled channel calculations. The fusion barrier distributions for 28,30 Si + 124 Sn systems have been obtained by quasi-elastic scattering measurements at backward angles and the results compared with the predictions of coupled channel calculations

Recent results on fusion and direct reactions with weakly bound stable nuclei

International Nuclear Information System (INIS)

Shrivastava, A.

2011-01-01

Recent measurements of fusion and direct reactions in case of weakly bound stable nuclei at extreme sub-barrier energies using a sensitive off beam technique are presented. First section deals with deep sub-barrier fusion cross-section measurement for 67 Li + 198 Pt followed by the study of fragment capture reaction of 7 Li + 198 Pt. Deviation in the slope of the fusion excitation function, as observed in case of medium heavy systems, is absent in the present asymmetric systems at these low energies. This study shows the absence of fusion hindrance, suggesting modifications in models that explain deep sub-barrier fusion data to incorporate weakly bound asymmetric systems

Electron beam welding using fusion and cold wire fill

International Nuclear Information System (INIS)

Kuncz, F.F.

1977-01-01

A straight-fusion (self-filler) welding technique generally poses no problem for electron beam welding. However, where control of penetration is a critical item and burn-through cannot be tolerated, this technique may not be satisfactory. To assure against beam-spike burn-through on a 1/4-inch deep weld joint, a low-power root-fusion pass, supplemented by numerous filler passes, was selected. However, this technique proved to have numerous problems. Voiding and porosity showed frequently in the first applications of this cold-wire filler process. Taper-out cratering, bead-edge undercutting, and spatter were also problems. These imperfections, however, were overcome. Employment of a circle generator provided the necessary heating of the joint walls to eliminate voids. The moving beam spot also provided a stirring action, lessening porosity. Taper-out cratering was eliminated by adjusting the timing of the current cutoff and wire-feed cutoff. Undercutting, bead height, and spatter were controlled by beam defocus

Diagnostic technique for measuring fusion reaction rate for inertial confinement fusion experiments at Shen Guang-III prototype laser facility

International Nuclear Information System (INIS)

Wang Feng; Peng Xiao-Shi; Liu Shen-Ye; Xu Tao; Kang Dong-Guo

2013-01-01

A study is conducted using a two-dimensional simulation program (Lared-s) with the goal of developing a technique to evaluate the effect of Rayleigh-Taylor growth in a neutron fusion reaction region. Two peaks of fusion reaction rate are simulated by using a two-dimensional simulation program (Lared-s) and confirmed by the experimental results. A neutron temporal diagnostic (NTD) system is developed with a high temporal resolution of ∼ 30 ps at the Shen Guang-III (SG-III) prototype laser facility in China, to measure the fusion reaction rate history. With the shape of neutron reaction rate curve and the spherical harmonic function in this paper, the degree of Rayleigh-Taylor growth and the main source of the neutron yield in our experiment can be estimated qualitatively. This technique, including the diagnostic system and the simulation program, may provide important information for obtaining a higher neutron yield in implosion experiments of inertial confinement fusion

Semi empirical model for astrophysical nuclear fusion reactions of 1≤Z≤15

International Nuclear Information System (INIS)

Manjunatha, H.C.; Seenappa, L.; Sridhar, K.N.

2017-01-01

The fusion reaction is one of the most important reactions in the stellar evolution. Due to the complicated reaction mechanism of fusion, there is great uncertainty in the reaction rate which limits our understanding of various stellar objects. Low z elements are formed through many fusion reactions such as "4He+"1"2C→"1"6O, "1"2C+"1"2C→"2"0Ne+"4He, "1"2C+"1"2C→"2"3Na, "1"2C+"1"2C→"2"3Mg, "1"6O+"1"6O→"2"8Si+"4He, "1"2C+"1H→"1"3N and "1"3C+"4He→"1"6O. A detail study is required on Coulomb and nuclear interaction in formation of low Z elements in stars through fusion reactions. For astrophysics, the important energy range extends from 1 MeV to 3 MeV in the center of mass frame, which is only partially covered by experiments. In the present work, we have studied the basic fusion parameters such as barrier heights (V_B), positions (R_B), curvature of the inverted parabola (ħω_1) for fusion barrier, cross section and compound nucleus formation probability (P_C_N) and fusion process in the low Z element (1≤Z≤15) formation process. For each isotope, we have studied all possible projectile-target combinations. We have also studied the astrophysical S(E) factor for these reactions. Based on this study, we have formulated the semi empirical relations for barrier heights (V_B), positions (R_B), curvature of the inverted parabola and hence for the fusion cross section and astrophysical S(E) factor. The values produced by the present model compared with the experiments and data available in the literature. (author)

Thermal, thermoelectric, and cathode poisoning effects in cold fusion experiments

International Nuclear Information System (INIS)

Keesing, R.G.; Greenhow, R.C.; Cohler, M.D.; McQuillan, A.J.

1991-01-01

This paper reports on an unsuccessful attempt to repeat the observations by Fleischmann and Pons of cold nuclear fusion in deuterium-charged palladium; no excess heat is found, nor is any gamma or neutron activity identified. Peltier heating at the palladium/platinum junction is investigated, but no effects are seen; the possibility remains, however, that a large Peltier coefficient may arise for deuterium concentrations that render the palladium-deuterium semiconducting. Finally, the effects of poisoning the palladium with cyanide were investigated

Competition between fusion and quasi-fission in heavy ion induced reactions

International Nuclear Information System (INIS)

Back, B.B.

1986-09-01

Quantitative analyses of angular distributions and angle-mass correlations have been applied to the U + Ca reaction to obtain upper limit estimates for the cross sections for complete fusion near or below the interaction barrier. Extrapolating to the systems Ca + Cm and Ca + Es using the well established scaling properties of the extra push model, an estimate of the cross sections relevant to the efforts of synthesizing super-heavy elements in the region Z = 116 and N = 184 via heavy-ion fusion reactions are obtained. A simple evaporation calculation using properties of the super heavy elements shows that the failure to observe super-heavy elements with the Ca + Cm reaction is consistent with estimates of the complete fusion process. 33 refs., 9 figs., 1 tab

Tunnelling effect enhanced by lattice screening as main cold fusion mechanism: An brief theoretical overview

International Nuclear Information System (INIS)

Frisone, F.

2007-01-01

In this paper are illustrated the main features of tunneling traveling between two deuterons within a lattice. Considering the screening effect due lattice electrons we compare the d-d fusion rate evaluated from different authors assuming different screening efficiency and different d-d potentials. Then, we propose a effective potential which describe very well the attractive contribute due to plasmon exchange between two deuterons and by means of it we will compute the d-d fusion rates for different energy values. Finally the good agreement between theoretical and experimental results proves the reality of cold fusion phenomena and the reliability of our model

The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

International Nuclear Information System (INIS)

Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H.

2002-01-01

The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H 2 O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction

Fusion reactions initiated by laser-accelerated particle beams in a laser-produced plasma

International Nuclear Information System (INIS)

Labaune, C.; Baccou, C.; Loisel, G.; Yahia, V.; Depierreux, S.; Goyon, C.; Rafelski, J.

2013-01-01

The advent of high-intensity-pulsed laser technology enables the generation of extreme states of matter under conditions that are far from thermal equilibrium. This in turn could enable different approaches to generating energy from nuclear fusion. Relaxing the equilibrium requirement could widen the range of isotopes used in fusion fuels permitting cleaner and less hazardous reactions that do not produce high-energy neutrons. Here we propose and implement a means to drive fusion reactions between protons and boron-11 nuclei by colliding a laser-accelerated proton beam with a laser-generated boron plasma. We report proton-boron reaction rates that are orders of magnitude higher than those reported previously. Beyond fusion, our approach demonstrates a new means for exploring low-energy nuclear reactions such as those that occur in astrophysical plasmas and related environments. (authors)

Fast Neutral reactions in cold interstellar clouds

International Nuclear Information System (INIS)

Graff, M.M.

1989-01-01

The dynamics of exothermic neutral reactions between radical species have been examined, with particular attention to reactivity at the very low energies characteristic of cold interstellar clouds. Long-range interactions (electrostatic and spin-orbit) were considered within in the adiabatic capture-infinite order sudden approximation (ACIOSA). Analytic expressions have been developed for cross sections and rate constants of exothermic reactions between atoms and dipolar radicals at low temperatures. A method for approximating the adiabatic potential surface for the reactive state will be presented. The reaction systems O+OH and O+CH are both predicted to be fast at low temperatures. The systems C+CH and C+OH are expected to be nonreactive at low temperatures, and upper limits of rate constants for these reactions have been estimated. General predictions are made for other reaction systems. Implications for interstellar chemistry will be discussed

Effect of projectile on incomplete fusion reactions at low energies

Directory of Open Access Journals (Sweden)

Sharma Vijay R.

2017-01-01

Full Text Available Present work deals with the experimental studies of incomplete fusion reaction dynamics at energies as low as ≈ 4 - 7 MeV/A. Excitation functions populated via complete fusion and/or incomplete fusion processes in 12C+175Lu, and 13C+169Tm systems have been measured within the framework of PACE4 code. Data of excitation function measurements on comparison with different projectile-target combinations suggest the existence of ICF even at slightly above barrier energies where complete fusion (CF is supposed to be the sole contributor, and further demonstrates strong projectile structure dependence of ICF. The incomplete fusion strength functions for 12C+175Lu, and 13C+169Tm systems are analyzed as a function of various physical parameters at a constant vrel ≈ 0.053c. It has been found that one neutron (1n excess projectile 13C (as compared to 12C results in less incomplete fusion contribution due to its relatively large negative α-Q-value, hence, α Q-value seems to be a reliable parameter to understand the ICF dynamics at low energies. In order to explore the reaction modes on the basis of their entry state spin population, the spin distribution of residues populated via CF and/or ICF in 16O+159Tb system has been done using particle-γ coincidence technique. CF-α and ICF-α channels have been identified from backward (B and forward (F α-gated γspectra, respectively. Reaction dependent decay patterns have been observed in different α emitting channels. The CF channels are found to be fed over a broad spin range, however, ICF-α channels was observed only for high-spin states. Further, the existence of incomplete fusion at low bombarding energies indicates the possibility to populate high spin states

Effect of projectile on incomplete fusion reactions at low energies

Science.gov (United States)

Sharma, Vijay R.; Shuaib, Mohd.; Yadav, Abhishek; Singh, Pushpendra P.; Sharma, Manoj K.; Kumar, R.; Singh, Devendra P.; Singh, B. P.; Muralithar, S.; Singh, R. P.; Bhowmik, R. K.; Prasad, R.

2017-11-01

Present work deals with the experimental studies of incomplete fusion reaction dynamics at energies as low as ≈ 4 - 7 MeV/A. Excitation functions populated via complete fusion and/or incomplete fusion processes in 12C+175Lu, and 13C+169Tm systems have been measured within the framework of PACE4 code. Data of excitation function measurements on comparison with different projectile-target combinations suggest the existence of ICF even at slightly above barrier energies where complete fusion (CF) is supposed to be the sole contributor, and further demonstrates strong projectile structure dependence of ICF. The incomplete fusion strength functions for 12C+175Lu, and 13C+169Tm systems are analyzed as a function of various physical parameters at a constant vrel ≈ 0.053c. It has been found that one neutron (1n) excess projectile 13C (as compared to 12C) results in less incomplete fusion contribution due to its relatively large negative α-Q-value, hence, α Q-value seems to be a reliable parameter to understand the ICF dynamics at low energies. In order to explore the reaction modes on the basis of their entry state spin population, the spin distribution of residues populated via CF and/or ICF in 16O+159Tb system has been done using particle-γ coincidence technique. CF-α and ICF-α channels have been identified from backward (B) and forward (F) α-gated γspectra, respectively. Reaction dependent decay patterns have been observed in different α emitting channels. The CF channels are found to be fed over a broad spin range, however, ICF-α channels was observed only for high-spin states. Further, the existence of incomplete fusion at low bombarding energies indicates the possibility to populate high spin states

Concerning the modelling of systems in terms of Quantum Electrodynamics: the special case of 'Cold Fusion'

International Nuclear Information System (INIS)

Abyaneh, Morteza; Fleischmann, Martin; Del Giudice, Emilio; Vitiello, Giuseppe

2006-01-01

A question we are asked repeatedly is: 'what are the causes of the opposition to your belief in the reality of 'Cold Fusion?'. This question is normally asked in the context of the statement that Quantum Mechanics shows that this phenomenon is impossible (a view that we share). Our answer is always based on the statement 'but what about the modelling of such systems in terms of QED?' which is always met by the insistence that Quantum Mechanics shows that Cold Fusion is impossible. We conclude that scientists do not understand QED or, if they have some understanding of this subject, then this must be subject to some major misconceptions. This pointless dialogue (perhaps more correctly described as two monologues conducted in parallel) and the insistence on the primacy of Quantum Mechanics in the modelling of systems in the Natural Sciences is unfortunate because it obscures the outcome of the investigations in the more normal fields of the Natural Sciences (more normal than Cold Fusion). A brief outline of the work which has led to the formulation of the concept of coherence will therefore be given under the aegis of the revolutions in our understanding of the Natural Sciences which has taken place since the latter part of the 19. Century. The main illustration of the way we can demonstrate the applicability of these concepts will be based on the study of nucleation and phase growth. The development of micro-electrode substrates allows us to study the statistics of the formation of the first nucleus; it will be shown that these statistics are strictly in line with concepts developed from QED coherence. We conclude that QED coherence is not just a concept to be confined to sub-atomic physics, cosmology etc. but that it pervades the modelling of the whole of the Natural Sciences including that of 'Cold Fusion'. Some of the major steps which have taken place in the development of this subject area will be illustrated

To the non-local theory of cold nuclear fusion.

Science.gov (United States)

Alexeev, Boris V

2014-10-01

In this paper, we revisit the cold fusion (CF) phenomenon using the generalized Bolzmann kinetics theory which can represent the non-local physics of this CF phenomenon. This approach can identify the conditions when the CF can take place as the soliton creation under the influence of the intensive sound waves. The vast mathematical modelling leads to affirmation that all parts of soliton move with the same velocity and with the small internal change of the pressure. The zone of the high density is shaped on the soliton's front. It means that the regime of the 'acoustic CF' could be realized from the position of the non-local hydrodynamics.

On the production of heavy elements by cold fusion

International Nuclear Information System (INIS)

Armbruster, P.

1985-01-01

After a short historical introduction (Section 1), this article presents new insights into the mechanism limiting the fusion of heavy nuclides (Section 2). Fusion is finally limited by the increasing Coulomb forces in the formation process of a compound system, as well as in its deexcitation. Moreover, nuclear structure effects in all stages of evaporation residue (EVR) formation are shown to be of importance. The wide field of fusion reaction studies and possible experimental techniques is projected onto the task of element synthesis, and only those aspects that are of relevance here are covered. The better understanding of EVR formation (Section 2) and the new experimental techniques (Section 3) that enabled the production of elements 107-109 (Section 4) are also discussed. In Section 5 ground-state properties and the nuclear structure of the heaviest isotopes, together with their production cross sections, are discussed. Finally, an outlook on how eventually to go beyond Z = 109 is given

Classical simulations of heavy-ion fusion reactions and weakly ...

Indian Academy of Sciences (India)

82, No. 5. — journal of. May 2014 physics pp. 879–891. Classical simulations of heavy-ion fusion reactions and weakly-bound projectile breakup reactions ... on the collision energy and the moment of inertia of the deformed nucleus. ... where each individual nucleus consists of a number of protons and neutrons, in some.

The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

Energy Technology Data Exchange (ETDEWEB)

Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H. [The University of Illinois, Urbana (United States)

2002-05-01

The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H{sub 2}O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction.

Process and device for energy production from thermonuclear fusion reactions

International Nuclear Information System (INIS)

Bussard, R.W.; Coppi, Bruno.

1977-01-01

An energy generating system is described using a fusion reaction. It includes several contrivances for confining a plasma in an area, a protective device around a significant part of each of these confinement contrivances, an appliance for introducing a fusion reaction fuel in each of the confinements so that the plasma may be formed. Each confinement can be separated from the protective device so that it may be replaced by another. The system is connected to the confinements, to the protective devices or to both. It enables the thermal energy to be extracted and transformed into another form, electric, mechanical or both [fr

Stochastic semi-classical description of sub-barrier fusion reactions

Directory of Open Access Journals (Sweden)

Ayik Sakir

2011-10-01

Full Text Available A semi-classical method that incorporates the quantum effects of the low-lying vibrational modes is applied to fusion reactions. The quantum effect is simulated by stochastic sampling of initial zero-point fluctuations of the surface modes. In this model, dissipation of the relative energy into non-collective excitations of nuclei can be included straightforwardly. The inclusion of dissipation is shown to increase the agreement with the fusion cross section data of Ni isotopes.

''Solid-state fusion'' effects

International Nuclear Information System (INIS)

Thompson, D.T.

1990-01-01

The ''Solid-State Fusion'' or ''Cold Fusion'' phenomenon, including excess heat generation and the production of nuclear particles, was first reported by Professors Martin Fleischmann and B. Stanley Pons in March 1989. The phenomenon described (the anomalous effects observed when deuterium oxide (heavy water) is electrolysed using a palladium cathode and a platinum anode in the presence of lithium deuteroxide) has many fascinating facets, not least of which is the fact that investigators are unable to produce the effects ''on demand''. Many of the experimental variables which seem to be significant were described and discussed at the ''First Annual Conference on Cold Fusion'' which was held in Salt Lake City, Utah, USA, from 29th to 31st March 1990. The information presented at the conference is summarised here. Some papers addressed the excess heat effects observed, some the nuclear particles, and others the theoretical aspects. These are reviewed. At the end of the conference Fleischmann summarised all the areas where apparent evidence for solid state fusion had been obtained during the past year, namely: excess enthalpy, bursts in enthalpy; tritium, bursts in tritium; neutrons, bursts in neutrons; X-rays, gamma rays and bursts in these. He recommended that emphasis should now be concentrated on confirming reaction products, such as He 4 . New theories were emerging, but one year was too short a time in which to evaluate them fully. (author)

Potential design modifications for the High Yield Lithium Injection Fusion Energy (HYLIFE) reaction chamber

International Nuclear Information System (INIS)

Pitts, J.H.; Hovingh, J.; Meier, W.R.; Monsler, M.J.; Powell, E.G.; Walker, P.E.

1979-01-01

Generation of electric power from inertial confinement fusion requires a reaction chamber. One promising type, the High Yield Lithium Injection Fusion Energy (HYLIFE) chamber, includes a falling array of liquid lithium jets. These jets act as: (1) a renewable first wall and blanket to shield metal components from x-ray and neutron exposure, (2) a tritium breeder to replace tritium burned during the fusion process, and (3) an absorber and transfer medium for fusion energy. Over 90% of the energy produced in the reaction chamber is absorbed in the lithium jet fall. Design aspects are included

Constraining statistical-model parameters using fusion and spallation reactions

Directory of Open Access Journals (Sweden)

Charity Robert J.

2011-10-01

Full Text Available The de-excitation of compound nuclei has been successfully described for several decades by means of statistical models. However, such models involve a large number of free parameters and ingredients that are often underconstrained by experimental data. We show how the degeneracy of the model ingredients can be partially lifted by studying different entrance channels for de-excitation, which populate different regions of the parameter space of the compound nucleus. Fusion reactions, in particular, play an important role in this strategy because they fix three out of four of the compound-nucleus parameters (mass, charge and total excitation energy. The present work focuses on fission and intermediate-mass-fragment emission cross sections. We prove how equivalent parameter sets for fusion-fission reactions can be resolved using another entrance channel, namely spallation reactions. Intermediate-mass-fragment emission can be constrained in a similar way. An interpretation of the best-fit IMF barriers in terms of the Wigner energies of the nascent fragments is discussed.

Spectroscopic study of 126I via incomplete fusion reaction

International Nuclear Information System (INIS)

Kanagalekar, B.A.; Das, Pragya; Kumar, Vinod; Kumar, R.; Singh, R.P.; Muralithar, S.; Bhowmik, R.K.

2006-01-01

The experiment at Inter University Accelerator Centre consisted of identifying the yrast high-spin states of 126 I using the incomplete fusion reaction 124 Sn ( 10 B, α4n) 126 I at beam energy of 70 MeV

Sonoluminescence: an IRaser creating cold fusion neutrons?

International Nuclear Information System (INIS)

Prevenslik, T.V.

1996-01-01

Sonoluminescence can be explained by treating the bubbles as IRasers with standing waves in resonance with the bubble dimensions. Since the IRaser resonant radiation is required to satisfy wave boundary conditions, the water molecules lining the bubble walls undergo a continuous population inversion as the bubble collapses. By stimulated processes, the Planck energy accumulates as the K b T energy of radiation photons is pumped from the surroundings through the rotational state of the water molecule. Bubble collapse occurs almost isothermally with the high IR absorptivity of the water molecule permitting the Planck energy to accumulate to 2∼6 eV only to be released by VIS-UV photon emission because of the low absorptivity of water at VIS-UV frequencies. As the IRaser cavity dimensions collapse to the spacing between water molecules at liquid density, soft x-rays at about 2 keV are predicted. But, this is less than 10 keV necessary for cold fusion so that no neutrons is directly expected yet. Therefore, it is suggested that UV laser enhancement is used to accumulate further bubble collapse energy

Kinetic advantage of controlled intermediate nuclear fusion

International Nuclear Information System (INIS)

Guo Xiaoming

2012-01-01

The dominated process of controlled fusion is to let nuclei gain enough kinetic energy to overcome Coulomb barrier. As a result, a fusion scheme can consider two factors in its design: to increase kinetic energy of nuclei and to alter the Coulomb barrier. Cold Fusion and Hot fusion are all one-factor schemes while Intermediate Fusion is a twofactors scheme. This made CINF kinetically superior. Cold Fusion reduces deuteron-deuteron distance, addressing Coulomb barrier, and Hot Fusion heat up plasma into extreme high temperature, addressing kinetic energy. Without enough kinetic energy made Cold Fusion skeptical. Extreme high temperature made Hot Fusion very difficult to engineer. Because CIFN addresses both factors, CIFN is a more promising technique to be industrialized.

Incomplete fusion reactions in 16O+159Tb system: Spin distribution measurements

Directory of Open Access Journals (Sweden)

Sharma Vijay R.

2015-01-01

Full Text Available In order to explore the reaction modes on the basis of their entry state spin population, an experiment has been done by employing particle-γ coincidence technique carried out at the Inter University Accelerator Centre, New Delhi. The preliminary analysis conclusively demonstrates, spin distribution for some reaction products populated via complete and/or incomplete fusion of 16O with 159Tb system found to be distinctly different. Further, the existence of incomplete fusion at low bombarding energies indicates the possibility to populate high spin states.

Temporal relationships between colds, upper respiratory viruses detected by polymerase chain reaction, and otitis media in young children followed through a typical cold season.

Science.gov (United States)

Winther, Birgit; Alper, Cuneyt M; Mandel, Ellen M; Doyle, William J; Hendley, J Owen

2007-06-01

Otitis media is a frequent complication of a viral upper respiratory tract infection, and the reported co-incidence of those diseases increases with assay sensitivity and sampling density. We determined the incidence of otitis-media complications in young children when referenced to cold-like illnesses and to concurrent virus recovery from the nasopharynx. A total of 60 children from 24 families were followed from October 2003 through April 30, 2004, by daily parental recording of illness signs, weekly pneumatic otoscopic examinations, and periodic polymerase chain reaction assay of collected nasal fluids for common viruses. One hundred ninety-nine cold-like illnesses were observed, but a sample for virus assay was not collected concurrent with 71 episodes. Of the remainder, 73% of cold-like illnesses were temporally related to recovery of 1 or a combination of the assayed viruses, with rhinovirus predominating. For non-cold-like illness periods, 54 (18%) of 297 assays were positive for virus, and the virus frequency distribution was similar to that for cold-like illnesses. There were 93 diagnosed otitis-media episodes; 65 (70%) of these occurred during a cold-like illness. For the 79 otitis-media episodes with available nasal samples, 61 (77%) were associated with a positive virus result. In this population, the otitis-media complication rate for a cold-like illness was 33%. A cold-like illness was not a prerequisite for polymerase chain reaction detection of viruses in the nose and nasopharynx of young children. Viral detection by polymerase chain reaction in the absence of a cold-like illness is associated with complications in some subjects. Otitis media is a complication of viral infection both with and without concurrent cold-like illnesses, thus downwardly biasing coincidence estimates that use cold-based illnesses as the denominator.

Fusion-fission dynamics and perspectives of future experiments

International Nuclear Information System (INIS)

Zagrebaev, V.I.; Itkis, M.G.; Oganessian, Yu.Ts.

2003-01-01

The paper is focused on reaction dynamics of superheavy-nucleus formation and decay at beam energies near the Coulomb barrier. The aim is to review the things we have learned from recent experiments on fusion-fission reactions leading to the formation of compound nuclei with Z ≥ 102 and from their extensive theoretical analysis. Major attention is paid to the dynamics of formation of very heavy compound nuclei taking place in strong competition with the process of fast fission (quasifission). The choice of collective degrees of freedom playing a fundamental role and finding the multidimensional driving potential and the corresponding dynamic equation regulating the whole process are discussed. A possibility of deriving the fission barriers of superheavy nuclei directly from performed experiments is of particular interest here. In conclusion, the results of a detailed theoretical analysis of available experimental data on the 'cold' and 'hot' fusion-fission reactions are presented. Perspectives of future experiments are discussed along with additional theoretical studies in this field needed for deeper understanding of the fusion-fission processes of very heavy nuclear systems

Reaching to a featured formula to deduce the energy of the heaviest particles producing from the controlled thermonuclear fusion reactions

Science.gov (United States)

Majeed, Raad H.; Oudah, Osamah N.

2018-05-01

Thermonuclear fusion reaction plays an important role in developing and construction any power plant system. Studying the physical behavior for the possible mechanism governed energies released by the fusion products to precise understanding the related kinematics. In this work a theoretical formula controlled the general applied thermonuclear fusion reactions is achieved to calculating the fusion products energy depending upon the reactants physical properties and therefore, one can calculate other parameters governed a given reaction. By using this formula, the energy spectrum of 4He produced from T-3He fusion reaction has been sketched with respect to reaction angle and incident energy ranged from (0.08-0.6) MeV.

Breakup-fusion analyses of light ion induced stripping reactions to both bound and unbound regions

International Nuclear Information System (INIS)

Lee, Y.J.

1987-01-01

The breakup-fusion theory developed recently by our group at the University of Texas has been very successful in explaining observed continuum spectra of particles emitted from breakup type reactions, such as (d,p), (h,p), (h,d), (α,p), and (α,t) reactions. The aim of the present work is to extend the breakup-fusion formalism to calculate the usual stripping reaction, in which a nucleon or a nucleon-cluster is transferred into abound orbit in the target nucleus. With this extension, it is now possible to calculate the spectra of particles emitted from stripping type reactions. We particularly explore the possibility of using the breakup-fusion theory as a spectroscopic tool to obtain information about single particle states in both bound and unbound regions. For this purpose, we extend the theory so as to include the spin-orbit interaction between the transferred particle and the target which has been neglected in all the breakup-fusion studies made in the past. We then apply the thus extended breakup-fusion theory to analyze data of (d,p) and (α,t) reactions. The results of the calculations fit the observed spectra very well and the BF method is shown indeed to be useful for extracting information about the single particle states observed as bumps in both the continuum and discrete regions

Charge-exchange and fusion reaction measurements during compression experiments with neutral beam heating in the Tokamak Fusion Test Reactor

International Nuclear Information System (INIS)

Kaita, R.; Heidbrink, W.W.; Hammett, G.W.

1986-04-01

Adiabatic toroidal compression experiments were performed in conjunction with high power neutral beam injection in the Tokamak Fusion Test Reactor (TFTR). Acceleration of beam ions to energies nearly twice the injection energy was measured with a charge-exchange neutral particle analyzer. Measurements were also made of 2.5 MeV neutrons and 15 MeV protons produced in fusion reactions between the deuterium beam ions and the thermal deuterium and 3 He ions, respectively. When the plasma was compressed, the d(d,n) 3 He fusion reaction rate increased a factor of five, and the 3 He(d,p) 4 He rate by a factor of twenty. These data were simulated with a bounce-averaged Fokker-Planck program, which assumed conservation of angular momentum and magnetic moment during compression. The results indicate that the beam ion acceleration was consistent with adiabatic scaling

Direct inner shell ionization accompanying heavy ion fusion reactions

International Nuclear Information System (INIS)

Sujkowski, Z.

1987-07-01

51 V+ 40 Ar (180 MeV) fusion reaction is studied by means of K X-ray-particle-γ-ray coincidences. K X-ray yields associated with various evaporation residues are determined separately for two ionization processes: the direct ionization by the projectile prior to the nuclear interaction and the postcollisional ionization due to the internal conversion of γ-rays. Implications for possible measurements of nuclear reaction times are discussed. 24 refs., 9 figs., 2 tabs. (author)

Energy dependence of fusion evaporation-residue cross sections in the 28Si+12C reaction

International Nuclear Information System (INIS)

Vineyard, M.F.; Mateja, J.F.; Beck, C.; Atencio, S.E.; Dennis, L.C.; Frawley, A.D.; Henderson, D.J.; Janssens, R.V.F.; Kemper, K.W.; Kovar, D.G.; Maguire, C.F.; Padalino, S.J.; Prosser, F.W.; Stephans, G.S.F.; Tiede, M.A.; Wilkins, B.D.; Zingarelli, R.A.

1993-01-01

Fusion evaporation-residue cross sections for the 28 Si+ 12 C reaction have been measured in the energy range 18≤E c.m. ≤136 MeV using time-of-flight techniques. Velocity distributions of mass-identified reaction products were used to identify evaporation residues and to determine the complete-fusion cross sections at high energies. The data are in agreement with previously established systematics which indicate an entrance-channel mass-asymmetry dependence of the incomplete-fusion evaporation-residue process. The complete-fusion evaporation-residue cross sections and the deduced critical angular momenta are compared with earlier measurements and the predictions of existing models

Search for a nuclear signature of the electrolytically induced cold fusion

International Nuclear Information System (INIS)

Wojtkowska, J.; Glowacki, S.; Jaskola, M.; Moroz, Z.; Ratynski, W.; Kedzierzawski, P.; Zoltowski, P.

1990-01-01

The neutron flux from the Pd-Pt electrolytic cell filled with D 2 O+D 2 SO 4 and D 2 O+LiOD was measured to search for the ''cold fusion'' induced in the deuterium stored in the palladium electrode. The fast-neutron ''long counter'', the scintillation detector with the NE - 213 liquid scintillator and with the PSD gamma-neutron distinguishing system and the scintillation detector of fast-neutron and/or gamma-ray bursts were used. No direct correlation was observed between the neutron flux measured in the presence or absence of the electrolysis. The upper limit is given for the neutron flux induced by the process under study. (author)

Evaluation of charged-particle reactions for fusion applications

International Nuclear Information System (INIS)

White, R.M.; Resler, D.A.; Warshaw, S.I.

1991-01-01

New evaluations of the total reaction cross sections for 2 H(d,n) 3 He, 2 H(d,p) 3 H, 3 H(t,2n) 4 He, 3 H(d,n) 4 He, and 3 He(d,p) 4 He have been completed. These evaluations are based on all known published data from 1946 to 1990 and include over 1150 measured data points from 67 references. The purpose of this work is to provide a consistent and well-documented set of cross sections for use in calculations relating to fusion energy research. A new thermonuclear data file, TDF, and a library of FORTRAN subprograms to read the file have been developed. Calculated from the new evaluations, the TDF file contains information on the Maxwellian-averaged reaction rates as a function of reaction and plasma temperature and the Maxwellian-averaged average energy of the interacting particles and reaction products. Routines are included that provide thermally-broadened spectral information for the secondary reaction products. 67 refs., 18 figs

Fusion and nonfusion phenomena in the 6Li+40Ca reaction at 156 MeV

International Nuclear Information System (INIS)

Brzychczyk, J.; Freindl, L.; Grotowski, K.

1982-01-01

Reaction products from 6 Li-induced reactions on 40 Ca at 156 MeV have been studied using the dE x E identification as well as the inclusive γ-ray method. The complete fusion cross-section has been found to be σsub(f)=(77 +- 11)mb. The Z distribution of fusion evaporation residues is compared with statistical model predictions. The Z spectrum of reaction products shows a maximum at 15 6 Li break-up. (author)

Fusion and nonfusion phenomena in the 6Li+40Ca reaction at 156 MeV

International Nuclear Information System (INIS)

Brzychczyk, J.; Freindl, L.; Grotowski, K.; Majka, Z.; Micek, S.; Planeta, R.; Uniwersytet Jagiellonski, Krakow; Albinska, M.; Buschmann, J.; Klewe-Nebenius, H.; Gils, H.J.; Rebel, H.; Zagromski, S.

1984-01-01

Reaction products from 6 Li-induced reactions on 40 Ca at 156 MeV have been studied using the dExE idenitification as well as the inclusive γ-ray method. The complete fusion cross section has been found to be sigmasub(F)=67 +- 20 mb. The Z-distribution of fusion evaporation residues is compared with statistical model predictions. The Z-spectrum of reaction products shows a maximum at 15 6 Li-break-up processes. (orig.)

Investigation of the influence of incomplete fusion on complete fusion of {sup 12}C-induced reactions at {approx} 4-7.2 MeV/nucleon

Energy Technology Data Exchange (ETDEWEB)

Amanuel, F.K. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy); Zelalem, B.; Chaubey, A.K. [Addis Ababa University, Department of Physics, P.O.Box 1176, Addis Ababa (Ethiopia); Agarwal, Avinash [Bareilly College, Department of Physics, Bareilly (India); Rizvi, I.A.; Maheshwari, Anjana; Ahmed, Tauseef [Aligarh Muslim University, Department of Physics, Aligarh (India)

2011-12-15

In this paper, we present the results of our investigation of reaction dynamics leading to incomplete fusion of heavy ions at moderate excitation energies, especially the influence of incomplete fusion on complete fusion of {sup 12}C -induced reactions at specific energies {approx} 4-7.2M eV/nucleon. Excitation functions of various reaction products populated via complete and/or incomplete fusions of a {sup 12}C projectile with {sup 93}Nb, {sup 59}Co and {sup 52}Cr targets were measured at several specific energies {approx} 4-7.2 MeV/nucleon, using a recoil catcher technique, followed by off-line {gamma}-ray spectrometry. The measured excitation functions were compared with theoretical values obtained using the PACE4 statistical model code. For representative non-{alpha}-emitting channels in the {sup 12}C + {sup 93}Nb system, the experimentally measured excitation functions were, in general, found to be in good agreement with the theoretical predictions. However, for {alpha}-emitting channels in the {sup 12}C + {sup 93}Nb, {sup 12}C + {sup 59}Co, and {sup 12}C + {sup 52}Cr systems, the measured excitation functions were higher than the predictions of the theoretical model code, which may be credited to incomplete fusion reactions at these energies. An attempt was made to estimate the incomplete fusion fraction for the present systems, which revealed that the fraction was sensitive to the projectile energy and mass asymmetry of the entrance channel. (orig.)

Influence of collective nonideal shielding on fusion reaction in partially ionized classical nonideal plasmas

Science.gov (United States)

Lee, Myoung-Jae; Jung, Young-Dae

2017-04-01

The collective nonideal effects on the nuclear fusion reaction process are investigated in partially ionized classical nonideal hydrogen plasmas. The effective pseudopotential model taking into account the collective and plasma shielding effects is applied to describe the interaction potential in nonideal plasmas. The analytic expressions of the Sommerfeld parameter, the fusion penetration factor, and the cross section for the nuclear fusion reaction in nonideal plasmas are obtained as functions of the nonideality parameter, Debye length, and relative kinetic energy. It is found that the Sommerfeld parameter is suppressed due to the influence of collective nonideal shielding. However, the collective nonideal shielding is found to enhance the fusion penetration factor in partially ionized classical nonideal plasmas. It is also found that the fusion penetration factors in nonideal plasmas represented by the pseudopotential model are always greater than those in ideal plasmas represented by the Debye-Hückel model. In addition, it is shown that the collective nonideal shielding effect on the fusion penetration factor decreases with an increase of the kinetic energy.

Experimental Cross Sections for Reactions of Heavy Ions and 208Pb, 209Bi, 238U, and 248Cm Targets

International Nuclear Information System (INIS)

Patin, Joshua B.

2002-01-01

The study of the reactions between heavy ions and 208 Pb, 209 Bi, 238 U, and 248 Cm targets was performed to look at the differences between the cross sections of hot and cold fusion reactions. Experimental cross sections were compared with predictions from statistical computer codes to evaluate the effectiveness of the computer code in predicting production cross sections. Hot fusion reactions were studied with the MG system, catcher foil techniques and the Berkeley Gas-filled Separator (BGS). 3n- and 4n-exit channel production cross sections were obtained for the 238 U( 18 O,xn) 256-x Fm, 238 U( 22 Ne,xn) 260-x No, and 248 Cm( 15 N,xn) 263-x Lr reactions and are similar to previous experimental results. The experimental cross sections were accurately modeled by the predictions of the HIVAP code using the Reisdorf and Schaedel parameters and are consistent with the existing systematics of 4n exit channel reaction products. Cold fusion reactions were examined using the BGS. The 208 Pb( 48 Ca,xn) 256-x No, 208 Pb( 50 Ti,xn) 258-x Rf, 208 Pb( 51 V,xn) 259-x Db, 209 Bi( 50 Ti,xn) 259-x Db, and 209 Bi( 51 V,xn) 260-x Sg reactions were studied. The experimental production cross sections are in agreement with the results observed in previous experiments. It was necessary to slightly alter the Reisdorf and Schaedel parameters for use in the HIVAP code in order to more accurately model the experimental data. The cold fusion experimental results are in agreement with current 1n- and 2n-exit channel systematics

Fusion energy

International Nuclear Information System (INIS)

Gross, R.A.

1984-01-01

This textbook covers the physics and technology upon which future fusion power reactors will be based. It reviews the history of fusion, reaction physics, plasma physics, heating, and confinement. Descriptions of commercial plants and design concepts are included. Topics covered include: fusion reactions and fuel resources; reaction rates; ignition, and confinement; basic plasma directory; Tokamak confinement physics; fusion technology; STARFIRE: A commercial Tokamak fusion power plant. MARS: A tandem-mirror fusion power plant; and other fusion reactor concepts

Fusion cross sections for 6,7Li + 24Mg reactions at energies below and above the barrier

International Nuclear Information System (INIS)

Ray, M.; Mukherjee, A.; Pradhan, M. K.; Kshetri, Ritesh; Sarkar, M. Saha; Dasmahapatra, B.; Palit, R.; Majumdar, I.; Joshi, P. K.; Jain, H. C.

2008-01-01

Measurement of fusion cross sections for the 6,7 Li + 24 Mg reactions by the characteristic γ-ray method has been done at energies from below to well above the respective Coulomb barriers. The fusion cross sections obtained from these γ-ray cross sections for the two systems are found to agree well with the total reaction cross sections at low energies. The relatively large difference between total cross sections and measured fusion cross sections at higher energies is consistent with the fact that other channels, in particular breakup, open up with an increase of bombarding energy. The breakup channel, however, appears not to have any influence on fusion cross sections. The critical angular momenta (l cr ) deduced from the fusion cross sections are found to have an energy dependence similar to other Li-induced reactions

Study of α-particle multiplicity in 16O+196Pt fusion-fission reaction

International Nuclear Information System (INIS)

Kapoor, K.; Kumar, A.; Bansal, N.

2016-01-01

Study of dynamics of fusion-fission reaction is one of the interesting parts of heavy-ion-induced nuclear reaction. Extraction of fission time scales using different probes is of central importance for understanding the dynamics of fusion-fission process. In the past, extensive theoretical and experimental efforts have been made to understand the various aspects of the heavy ion induced fusion-fission reactions. Compelling evidences have been obtained from the earlier studies that the fission decay of hot nuclei is protracted process i.e. slowed down relative to the expectations of the standard statistical model, and large dynamical delays are required due to this hindrance. Nuclear dissipation is assumed to be responsible for this delay and more light particles are expected to be emitted during the fission process. One of neutron multiplicity measurements have been performed for the 16,18 O+ 194,198 Pt populating the CN 210,212,214,216 Rn and observed fission delay due to nuclear viscosity. In order to have complete understanding for the dynamics of 212 Rn nucleus, we measured the charged particle multiplicity for 16 O+ 196 Pt system. Study of charged particles will give us more information about the emitter in comparison to neutrons as charged particles faces Coulomb barrier and are more sensitive probe for understanding the dynamics of fusion-fission reactions. In the present work, we are reporting some of the preliminary results of charged particle multiplicity

Understanding fuel magnetization and mix using secondary nuclear reactions in magneto-inertial fusion.

Science.gov (United States)

Schmit, P F; Knapp, P F; Hansen, S B; Gomez, M R; Hahn, K D; Sinars, D B; Peterson, K J; Slutz, S A; Sefkow, A B; Awe, T J; Harding, E; Jennings, C A; Chandler, G A; Cooper, G W; Cuneo, M E; Geissel, M; Harvey-Thompson, A J; Herrmann, M C; Hess, M H; Johns, O; Lamppa, D C; Martin, M R; McBride, R D; Porter, J L; Robertson, G K; Rochau, G A; Rovang, D C; Ruiz, C L; Savage, M E; Smith, I C; Stygar, W A; Vesey, R A

2014-10-10

Magnetizing the fuel in inertial confinement fusion relaxes ignition requirements by reducing thermal conductivity and changing the physics of burn product confinement. Diagnosing the level of fuel magnetization during burn is critical to understanding target performance in magneto-inertial fusion (MIF) implosions. In pure deuterium fusion plasma, 1.01 MeV tritons are emitted during deuterium-deuterium fusion and can undergo secondary deuterium-tritium reactions before exiting the fuel. Increasing the fuel magnetization elongates the path lengths through the fuel of some of the tritons, enhancing their probability of reaction. Based on this feature, a method to diagnose fuel magnetization using the ratio of overall deuterium-tritium to deuterium-deuterium neutron yields is developed. Analysis of anisotropies in the secondary neutron energy spectra further constrain the measurement. Secondary reactions also are shown to provide an upper bound for the volumetric fuel-pusher mix in MIF. The analysis is applied to recent MIF experiments [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z Pulsed Power Facility, indicating that significant magnetic confinement of charged burn products was achieved and suggesting a relatively low-mix environment. Both of these are essential features of future ignition-scale MIF designs.

Synthesis and decay process of superheavy nuclei with Z=119-122 via hot-fusion reactions

Energy Technology Data Exchange (ETDEWEB)

Ghahramany, N.; Ansari, A. [Shiraz University, Department of Physics and Biruni Observatory, College of Science, Shiraz (Iran, Islamic Republic of)

2016-09-15

In this research article attempts have been made to calculate the superheavy-nuclei synthesis characteristics including, the potential energy parameters, fusion probability, fusion and evaporation residue (ER) cross sections as well as, decay properties of compound nucleus and the residue nuclei formation probability for elements with Z=119-122 by using the hot-fusion reactions. It is concluded that, although a selection of double magic projectiles such as {sup 48}Ca with high binding energy, simplifies the calculations significantly due to spherical symmetric shape of the projectile, resulting in high evaporation residue cross section, unfortunately, nuclei with Z > 98 do not exist in quantities sufficient for constructing targets for the hot-fusion reactions. Therefore, practically our selection is fusion reactions with titanium projectile because the mass production of target nuclei for experimental purposes is more feasible. Based upon our findings, it is necessary, for new superheavy-nuclei production with Z > 119, to use neutron-rich projectiles and target nuclei. Finally, the maximal evaporation residue cross sections for the synthesis of superheavy elements with Z=119-122 have been calculated and compared with the previously founded ones in the literature. (orig.)

Search for a nuclear signature of the electrolytically induced cold fusion

Energy Technology Data Exchange (ETDEWEB)

Wojtkowska, J; Glowacki, S; Jaskola, M; Moroz, Z; Ratynski, W [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland); Kedzierzawski, P; Zoltowski, P [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland)

1990-01-01

The neutron flux from the Pd-Pt electrolytic cell filled with D{sub 2}O+D{sub 2}SO{sub 4} and D{sub 2}O+LiOD was measured to search for the ``cold fusion`` induced in the deuterium stored in the palladium electrode. The fast-neutron ``long counter``, the scintillation detector with the NE - 213 liquid scintillator and with the PSD gamma-neutron distinguishing system and the scintillation detector of fast-neutron and/or gamma-ray bursts were used. No direct correlation was observed between the neutron flux measured in the presence or absence of the electrolysis. The upper limit is given for the neutron flux induced by the process under study. (author).

Congress turns cold on fusion

International Nuclear Information System (INIS)

Marshall, E.

1984-01-01

A 5% cut in fusion research budgets will force some programs to be dropped in order to keep the large machinery running unless US and European scientists collaborate instead of competing. Legislators became uneasy about the escalating costs of the new devices. The 1984 budget of $470 million for magnetic fusion research is only half the projected cost of the Tokomak Fusion Core Experiment (TFCX) planned to ignite, for the first time, a self-sustaining burn. Planning for the TCFX continued despite the message from Congress. Work at the large institutions at Princeton, MIT, etc. may survive at the expense of other programs, some of which will lose academic programs as well. Scientists point to the loss of new ideas and approaches when projects are cancelled. Enthusiasm is growing for international collaboration

Description of heavy-ion fusion in terms of direct reaction theory

International Nuclear Information System (INIS)

Hong, S.W.

1987-01-01

A direct reaction description of the heavy-ion fusion, proposed by Udagawa, Kim and Tamura, has been successfully used in calculating the fusion cross sections and the spin distributions for a number of systems in the energy regions from the sub-barrier to the above-barrier region. A fusion potential is introduced in this theory and the radius of the fusion potential is treated as an adjustable parameter. The theory is thus a one-parameter theory. The results obtained by Udagawa, Kim and Tamura showed that the radius parameter ranges from 1.4 to 1.5 fm, which is much larger than the radius (1.0 fm) used in other models. A hard evidence is shown to demonstrate the necessity of the long-ranged fusion potential radius in the near-barrier region. In the above-barrier region, the use of the energy-dependent optical potential and the energy-dependent fusion potential radius is proved to be essential in reproducing the measured fusion cross sections. As a further application of the theory, the double folded potential model is utilized to provide the real part of the optical potential. The imaginary part of the optical potential is determined so that not only the elastic scattering but also the fusion cross sections can be reproduced

Comparison of cross sections for C+O reactions in the second regime of complete fusion

International Nuclear Information System (INIS)

Beck, C.; Haas, F.; Freeman, R.M.; Heusch, B.; Coffin, J.P.; Guillaume, G.; Rami, F.; Wagner, P.

1985-01-01

Kinetic energy spectra, angular distributions, and elemental yield distributions have been measured for the 12 C + 16 O, 12 C + 18 O and 13 C + 17 O reaction products over an energy range from 2 to 7 times the Coulomb barrier energy. A careful kinematic analysis of the evaporation residues and comparisons with statistical model calculations show that fusion proceeds with full momentum transfer followed by a statistical decay of the compound nucleus. The competition between complete fusion process and peripheral reactions in the 12 C + 16 O system is less important than for the 12 C + 18 O and 13 C + 17 O reactions. The unexpectedly high 12 C + 16 O complete fusion cross sections are related to the possible occurence of a superdeformation of the 28 Si compound nucleus

Recent experimental results in sub- and near-barrier heavy-ion fusion reactions

Energy Technology Data Exchange (ETDEWEB)

Montagnoli, Giovanna [Dipartimento di Fisica e Astronomia, Universita di Padova (Italy); INFN Sezione di Padova (Italy); Stefanini, Alberto M. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy)

2017-08-15

Recent advances obtained in the field of near and sub-barrier heavy-ion fusion reactions are reviewed. Emphasis is given to the results obtained in the last decade, and focus is mainly on the experimental work performed concerning the influence of transfer channels on fusion cross sections and the hindrance phenomenon far below the barrier. Indeed, early data of sub-barrier fusion taught us that cross sections may strongly depend on the low-energy collective modes of the colliding nuclei, and, possibly, on couplings to transfer channels. The coupled-channels (CC) model has been quite successful in the interpretation of the experimental evidences. Fusion barrier distributions often yield the fingerprint of the relevant coupled channels. Recent results obtained by using radioactive beams are reported. At deep sub-barrier energies, the slope of the excitation function in a semi-logarithmic plot keeps increasing in many cases and standard CC calculations overpredict the cross sections. This was named a hindrance phenomenon, and its physical origin is still a matter of debate. Recent theoretical developments suggest that this effect, at least partially, may be a consequence of the Pauli exclusion principle. The hindrance may have far-reaching consequences in astrophysics where fusion of light systems determines stellar evolution during the carbon and oxygen burning stages, and yields important information for exotic reactions that take place in the inner crust of accreting neutron stars. (orig.)

Why You Should Believe Cold Fusion is Real

Science.gov (United States)

Storms, Edmund K.

2005-03-01

Nuclear reactions are now claimed to be initiated in certain solid materials at an energy too low to overcome the Coulomb barrier. These reactions include fusion, accelerated radioactive decay, and transmutation involving heavy elements. Evidence is based on hundreds of measurements of anomalous energy using a variety of calorimeters at levels far in excess of error, measurement of nuclear products using many normally accepted techniques, observations of many patterns of behavior common to all studies, measurement of anomalous energetic emissions using accepted techniques, and an understanding of most variables that have hindered reproducibility in the past. This evidence can be found at www.LENR-CANR.orgwww.LENR-CANR.org. Except for an accepted theory, the claims have met all requirements normally required before a new idea is accepted by conventional science, yet rejection continues. How long can the US afford to reject a clean and potentially cheap source of energy, especially when other nations are attempting to develop this energy and the need for such an energy source is so great?

New approach to description of fusion-fission dynamics in super-heavy element formation

International Nuclear Information System (INIS)

Zagrebaev, V.I.

2002-01-01

A new mechanism of the fusion-fission process for a heavy nuclear system is proposed, which takes place in the (A 1 , A 2 ) space, where A 1 and A 2 are two nuclei, surrounded by a certain number of shared nucleons ΔA. The nuclei A 1 and A 2 gradually lose (or acquire) their individualities with increasing (or decreasing) a number of collectivized nucleons ΔA. The driving potential in the (A 1 , A 2 ) space is derived, which allows the calculation of both the probability of the compound nucleus formation and the mass distribution of fission and quasi-fission fragments in heavy ion fusion reactions. The cross sections of super-heavy element formation in the 'hot' and 'cold' fusion reactions have been calculated up to Z CN =118. (author)

Search for entrance channel effects in fusion reactions via neutron evaporation

International Nuclear Information System (INIS)

Ajay Kumar; Kaur, J.; Kumar, A.; Singh, G.; Govil, I.M.; Rakesh Kumar; Datta, S.K.; Chatterjee, M.B.; Yogi, B.K.

2001-01-01

It is generally expected that the compound nuclei formed at the given excitation energies and the angular momenta follow a statistical decay pattern independent of a particular reaction that led to fusion. In order to search the entrance channel effects in the decay of compound nucleus, the reaction 16 O + 64 Zn at oxygen beam energy of 91 MeV and 95 MeV are investigated

SU-F-T-140: Assessment of the Proton Boron Fusion Reaction for Practical Radiation Therapy Applications Using MCNP6

Energy Technology Data Exchange (ETDEWEB)

Adam, D; Bednarz, B [University of Wisconsin, Madison, WI (United States)

2016-06-15

Purpose: The proton boron fusion reaction is a reaction that describes the creation of three alpha particles as the result of the interaction of a proton incident upon a 11B target. Theoretically, the proton boron fusion reaction is a desirable reaction for radiation therapy applications in that, with the appropriate boron delivery agent, it could potentially combine the localized dose delivery protons exhibit (Bragg peak) and the local deposition of high LET alpha particles in cancerous sites. Previous efforts have shown significant dose enhancement using the proton boron fusion reaction; the overarching purpose of this work is an attempt to validate previous Monte Carlo results of the proton boron fusion reaction. Methods: The proton boron fusion reaction, 11B(p, 3α), is investigated using MCNP6 to assess the viability for potential use in radiation therapy. Simple simulations of a proton pencil beam incident upon both a water phantom and a water phantom with an axial region containing 100ppm boron were modeled using MCNP6 in order to determine the extent of the impact boron had upon the calculated energy deposition. Results: The maximum dose increase calculated was 0.026% for the incident 250 MeV proton beam scenario. The MCNP simulations performed demonstrated that the proton boron fusion reaction rate at clinically relevant boron concentrations was too small in order to have any measurable impact on the absorbed dose. Conclusion: For all MCNP6 simulations conducted, the increase of absorbed dose of a simple water phantom due to the 11B(p, 3α) reaction was found to be inconsequential. In addition, it was determined that there are no good evaluations of the 11B(p, 3α) reaction for use in MCNPX/6 and further work should be conducted in cross section evaluations in order to definitively evaluate the feasibility of the proton boron fusion reaction for use in radiation therapy applications.

Competition between peripheral and central emission in incomplete fusion reactions

International Nuclear Information System (INIS)

Tricoire, H.

1984-01-01

In the frame of a classical model we show that the emission of fast particles in incomplete fusion reactions may occur either from a PEP emission which happens preferentially at low angular momenta or from an inertial emission with a maximum of the cross section located near the critical angular momentum for complete fusion. The competition of these mechanisms depends crucialy of the interaction between the particle to be emitted and the target nucleus. Numerical calculations are performed with various particle target potentials. Using a proximity potential, one gets results in good agreement with experimental data

Study of heavy ion fusion reaction of 58Ni + 24Mg at 11 MeV/nucleon

International Nuclear Information System (INIS)

Shea, J.Y.

1991-01-01

This thesis presents a study of the heavy ion fusion reaction in which a 58 Ni projectile bombards a 24 Mg target at 11 MeV/nucleon. The incident projectile energy was purposefully chosen so as the system studied to be at the onset of the more complex and interesting phenomenon of incomplete fusion. The physics motivation is to probe the central collision of a heavy, energetic, and asymmetric system by means of both inclusive and exclusive experimental measurements. The experiment was performed at HHIRF (Holifield Heavy Ion Research Facility) by using the coupled accelerators at Oak Ridge National Laboratory. The reaction products were measured by the new open-quotes HILI-Ringclose quotes large solid angle detector system at Oak Ridge National Laboratory. The thesis discusses the physics motivation and the systematics of heavy ion fusion reactions. Details of the design and construction of a new CsI(T1) Ring detector is given. Since this is the first such study performed on the Heavy Ion Light Ion (HILI) detector, an extensive discussion of the calibration procedures and the data reduction methods are given. The fusion reaction data were analyzed in both inclusive and exclusive modes with the result that a valuable new perspective on the deconvolution of the reaction mechanism has been achieved

Application of spin-polarized fuel to fusion reactions

International Nuclear Information System (INIS)

Wakuta, Y.; Nakao, Y.; Honda, T.; Honda, Y.; Nakashima, H.

1990-01-01

Studies on the application of the polarized fuel to the inertial fusion reaction have been carried out. It is shown that the use of the spin-polarized fuel D vector·T vector or D vector· 3 (He)vector reduces the irradiating laser power more than 50% compared with the use of the unpolarized fuel. The depolarization rate of the polarized fuel during the fusing process is found to be almost negligible. (author)

Nuclear phenomena in low-energy nuclear reaction research.

Science.gov (United States)

Krivit, Steven B

2013-09-01

This is a comment on Storms E (2010) Status of Cold Fusion, Naturwissenschaften 97:861-881. This comment provides the following remarks to other nuclear phenomena observed in low-energy nuclear reactions aside from helium-4 make significant contributions to the overall energy balance; and normal hydrogen, not just heavy hydrogen, produces excess heat.

Gamma-ray emission spectrum from thermonuclear fusion reactions without intrinsic broadening

DEFF Research Database (Denmark)

Nocente, M.; Källne, J.; Salewski, Mirko

2015-01-01

First principle calculations of the gamma-ray energy spectrum arising from thermonuclear reactions without intrinsic broadening in fusion plasmas are presented, extending the theoretical framework needed to interpret measurements up to the accuracy level enabled by modern high resolution instrume......First principle calculations of the gamma-ray energy spectrum arising from thermonuclear reactions without intrinsic broadening in fusion plasmas are presented, extending the theoretical framework needed to interpret measurements up to the accuracy level enabled by modern high resolution...... instruments. An analytical formula for the spectrum from Maxwellian plasmas, which extends to higher temperatures than the results previously available in the literature, has been derived and used to discuss the assumptions and limitations of earlier models. In case of radio-frequency injection, numerical...... results based on a Monte Carlo method are provided, focusing in particular on improved relations between the peak shift and width from the reaction and the temperature of protons accelerated by radio-frequency heating.The results presented in this paper significantly improve the accuracy of diagnostic...

Some introductory notes on the problem of nuclear energy by controlled fusion reactions

International Nuclear Information System (INIS)

Pedretti, E.

1988-01-01

Written for scientists and technologist interested in, but unfamiliar with nuclear energy by controlled fusion reactions, this ''sui generis'' review paper attempts to provide the reader, as shortly as possible, with a general idea of the main issues at stake in nuclear fusion research. With the purpose of keeping this paper within a reasonable length, the various subjects are only outlined in their essence, basic features, underlying principles, etc., without entering into details, which are left to the quoted literature. Due to the particular readership of this journal, vacuum problems and/or aspects of fusion research anyhow related with vacuum science and technology are evidentiated. After reviewing fusion reactions' cross sections, fusion by accelerators and muon catalyzed fusion are described, followed by mention of Lawson's criteria and of plasma confinement features. Then, inertial confinement fusion is dealt with, also including one example of laser system (Nova), one of accelerator facility (PBFA-II) and some guesses on the classified Centurion-Halite program. Magnetic confinement fusion research is also reviewed, in particulary reporting one example of linear machine (MFTF-B), two examples of toroidal machines other than Tokamak (ATF and Eta-Beta-II) and various examples of Tokamaks, including PBX and PBX-M; TFTR, JET, JT-60, T-15 and Tore-Supra (large machines); Alcator A, FT, Alcator C/MTX, Alcator C-Mod and T-14 (compact high field machines). Tokamaks under design for ignition experiments (Ignitor, CIT, Ignitex and NET) are also illustrated. Thermal conversion of fusion power and direct generation of electricity are mentioned; conceptual design of fusion power plants are considered and illustrated by four examples (STARFIRE, WILDCAT, MARS and CASCADE). The D 3 He fuel cycle is discussed as an alternative more acceptable than Deuterium-Tritium, and thw Candor proposal is reported. After recalling past experience of the fission power development, some

Formation, separation and detection of evaporation residues produced in complete fusion reactions

CERN Document Server

Sagaidak, R N

2015-01-01

Some aspects of formation, separation and detection of evaporation residues (ERs) produced in complete fusion reactions induced by accelerated heavy ions are considered. These reactions allow to obtain heavy neutron-deficient nuclei and to study their properties. The statistical model analysis of the production cross sections for these nuclei obtained in a wide range of their neutron numbers allows to trace the changes in their macroscopic properties such as fission barriers. The fusion probability of massive projectile and target nuclei is of interest. Empirical estimates of this value allow to verify the predictions of theoretical models for the optimal ways of synthesis of unknown nuclei. Some peculiarities in the separation and detection of ERs in experiments are briefly considered by the example of the Ra ERs produced in the 12 C+Pb reactions. The reliable cross sections for ERs produced in very asymmetric projectile-target combination, such as 12 C+Pb, are important for the em...

Effects of breakup of weakly bound projectile and neutron transfer on fusion reactions around Coulomb barrier

International Nuclear Information System (INIS)

Lin, C.J.; Zhang, H.Q.; Yang, F.; Ruan, M.; Liu, Z.H.; Wu, Y.W.; Wu, X.K.; Zhou, P.; Zhang, C.L.; Zhang, G.L.; An, G.P.; Jia, H.M.; Xu, X.X.

2007-01-01

The excitation functions of quasielastic and elastic scattering at backward angles have been measured for the systems of 16 O+ 152 Sm, 6,7 Li+ 208 Pb and 32 S+ 90,96 Zr. The barrier distributions are extracted from these measured excitation functions and compared with the corresponding fusion barrier distributions. Except some details, the barrier distributions derived from the data of fusion and quasielastic/elastic scattering are almost the same for the tightly bound reaction systems. For the reaction systems with weakly bound projectile, the barrier distributions extracted from quasielastic scattering are obviously different from the fusion barrier distributions. However, the barrier distributions extracted from the excitation functions of the quasielastic scattering plus breakup are almost the same as the one extracted from the complete fusion data. This result means that barrier distribution not only bears the information of nuclear structures but also contains the knowledge of reaction mechanisms. Our results show that the complete fusion of the weakly bound projectile with heavy target is suppressed at the above barrier energies as compared with the model predictions. In addition, the measured barrier distribution of 32 S+ 96 Zr is broaden and extends to lower energy than in the case of 32 S+ 90 Zr due to the coupling of neutron transfer with positive Q-values, which result in a significant enhancement of fusion cross sections at the subbarrier energies

Evaluation of early tissue reactions after lumbar intertransverse process fusion using CT in a rabbit

International Nuclear Information System (INIS)

Shinbo, Jun; Mainil-Varlet, Pierre; Watanabe, Atsuya; Pippig, Suzanne; Koener, Jens; Anderson, Suzanne E.

2010-01-01

The objective of the study was to evaluate tissue reactions such as bone genesis, cartilage genesis and graft materials in the early phase of lumbar intertransverse process fusion in a rabbit model using computed tomography (CT) imaging with CT intensity (Hounsfield units) measurement, and to compare these data with histological results. Lumbar intertransverse process fusion was performed on 18 rabbits. Four graft materials were used: autograft bone (n=3); collagen membrane soaked with recombinant human bone morphogenetic protein-2 (rhBMP-2) (n=5); granular calcium phosphate (n=5); and granular calcium phosphate coated with rhBMP-2 (n=5). All rabbits were euthanized 3 weeks post-operatively and lumbar spines were removed for CT imaging and histological examination. Computed tomography imaging demonstrated that each fusion mass component had the appropriate CT intensity range. CT also showed the different distributions and intensities of bone genesis in the fusion masses between the groups. Each component of tissue reactions was identified successfully on CT images using the CT intensity difference. Using CT color mapping, these observations could be easily visualized, and the results correlated well with histological findings. The use of CT intensity is an effective approach for observing and comparing early tissue reactions such as newly synthesized bone, newly synthesized cartilage, and graft materials after lumbar intertransverse process fusion in a rabbit model. (orig.)

Experiments in order to reproduce cold fusion results

International Nuclear Information System (INIS)

Bimbot, R.; Blain, G.; Boureau, G.; Cieur, M.

1989-01-01

Three experiments have been performed in order to try and reproduce the cold fusion experiments reported by FLEISCHMANN and PONS (D 2 O electrolysis) and by the Frascati Group (D 2 absorption in Ti at liquid nitrogen temperature). In the two electrolysis experiments, a Pd cathode was used together with a Pt anode and a Pd (D 2 ) reference electrode, in acid and basic media. The electrolysis cell was surrounded by four neutron counters filled with an organic scintillator (NE213). The electronics made it possible to discriminate neutrons from gamma rays. The global efficiency for neutron detection was 20%, and the detection threshold was equal to 1 neutron/s/4π. A germanium detector (efficiency 70%) and a NaI crystal were used to record gamma ray spectra. In one of the experiments, tritium was measured in the solution before and after electrolysis. None of the two experiments showed neutron, gamma, or tritium production above background. In the third experiment, deuterium was absorbed in titanium by cooling at liquid nitrogen temperature, and desorbed by warming up at room temperature; both neutron and gamma emissions were recorded during these operations. The results of this experiment were also negative [fr

Fusion cross-sections of 16O+16O reaction in pseudonucleon picture

International Nuclear Information System (INIS)

Mishra, R.C.; Waghmare, Y.R.

1991-01-01

Fusion cross-sections for 16 O+ 16 O reaction are calculated in classical equations of motion approach using the pseudonucleon picture. These calculated fusion cross-sections are very close to measured values than earlier calculated using the same NN interaction. The aim of the paper is to test the pseudonucleon picture. Use of this picture does not require one to consider the number of relative random orientations of the colliding clusters. (author). 22 refs., 2 tabs., 4 figs

Relevance, Realization and stability of a cold layer at the plasma edge for fusion reactors

International Nuclear Information System (INIS)

1990-09-01

The workshop was dedicated to the realization and stability of a cold layer at the plasma edge for fusion reactors. The subjects of the communications presented were: impurity transport, and control, plasma boundary layers, power balance, radiation control and modifications, limiter discharges, tokamak density limit, Asdex divertor discharges, thermal stability of a radiating diverted plasma, plasma stability, auxiliary heating in Textor, detached plasma in Tore Supra, poloidal divertor tokamak, radiation cooling, neutral-particle transport, plasma scrape-off layer, edge turbulence

Hydrogen-Oxygen Reaction Assessment in the HANARO Cold Neutron Source

International Nuclear Information System (INIS)

Choi, Jung Woon; Kim, Hark Rho; Lee, Kye Hong; Han, Young Soo; Kim, Young Ki; Kim, Seok Hoon; Jeong, Jong Tae

2006-04-01

Liquid hydrogen, filled in the moderator cell of the in-pool assembly (IPA), is selected as a moderator to moderate thermal neutrons into cold neutrons for the HANARO Cold Neutron Source. Since the IPA will be installed in the vertical CN hole of the reflector tank at HANARO, the vacuum chamber (VC), the pressure boundary against the reactor, should withstand the detonation pressure so as to avoid any physical damage on the reactor under the hydrogen-oxygen chemical reaction. Accordingly, not only will the vacuum chamber be designed to keep its integrity against the hydrogen accident, but also the hydrogen and vacuum system will be designed with the leak-tight concept and also designed to be surrounded by the inert gas blanket system to prevent any air intrusion into the system. Also, in order to confirm the design concept of the CNS as well as VC integrity against the hydrogen accident, the hydrogen-oxygen chemical reaction is evaluated in this report by several methodologies: AICC methodology, Equivalent TNT detonation methodology, Explosion test result, and Calculation of VC strain under the maximum reflected explosion load

Hydrogen-Oxygen Reaction Assessment in the HANARO Cold Neutron Source

Energy Technology Data Exchange (ETDEWEB)

Choi, Jung Woon; Kim, Hark Rho; Lee, Kye Hong; Han, Young Soo; Kim, Young Ki; Kim, Seok Hoon; Jeong, Jong Tae

2006-04-15

Liquid hydrogen, filled in the moderator cell of the in-pool assembly (IPA), is selected as a moderator to moderate thermal neutrons into cold neutrons for the HANARO Cold Neutron Source. Since the IPA will be installed in the vertical CN hole of the reflector tank at HANARO, the vacuum chamber (VC), the pressure boundary against the reactor, should withstand the detonation pressure so as to avoid any physical damage on the reactor under the hydrogen-oxygen chemical reaction. Accordingly, not only will the vacuum chamber be designed to keep its integrity against the hydrogen accident, but also the hydrogen and vacuum system will be designed with the leak-tight concept and also designed to be surrounded by the inert gas blanket system to prevent any air intrusion into the system. Also, in order to confirm the design concept of the CNS as well as VC integrity against the hydrogen accident, the hydrogen-oxygen chemical reaction is evaluated in this report by several methodologies: AICC methodology, Equivalent TNT detonation methodology, Explosion test result, and Calculation of VC strain under the maximum reflected explosion load.

Multi-Sampling Ionization Chamber (MUSIC) for measurements of fusion reactions with radioactive beams

International Nuclear Information System (INIS)

Carnelli, P.F.F.; Almaraz-Calderon, S.; Rehm, K.E.; Albers, M.; Alcorta, M.; Bertone, P.F.; Digiovine, B.; Esbensen, H.; Fernández Niello, J.; Henderson, D.; Jiang, C.L.; Lai, J.; Marley, S.T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R.C.; Paul, M.; Ugalde, C.

2015-01-01

A detection technique for high-efficiency measurements of fusion reactions with low-intensity radioactive beams was developed. The technique is based on a Multi-Sampling Ionization Chamber (MUSIC) operating as an active target and detection system, where the ionization gas acts as both target and counting gas. In this way, we can sample an excitation function in an energy range determined by the gas pressure, without changing the beam energy. The detector provides internal normalization to the incident beam and drastically reduces the measuring time. In a first experiment we tested the performance of the technique by measuring the 10,13,15 C+ 12 C fusion reactions at energies around the Coulomb barrier

Multi-Sampling Ionization Chamber (MUSIC) for measurements of fusion reactions with radioactive beams

Energy Technology Data Exchange (ETDEWEB)

Carnelli, P.F.F. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Laboratorio TANDAR, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, B1650KNA, San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917, C1033AAJ Buenos Aires (Argentina); Almaraz-Calderon, S. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Rehm, K.E., E-mail: rehm@anl.gov [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Albers, M.; Alcorta, M.; Bertone, P.F.; Digiovine, B.; Esbensen, H. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Fernández Niello, J. [Laboratorio TANDAR, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, B1650KNA, San Martín, Buenos Aires (Argentina); Universidad Nacional de San Martín, Campus Miguelete, B1650BWA San Martín, Buenos Aires (Argentina); Henderson, D.; Jiang, C.L. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Lai, J. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Marley, S.T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R.C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem (Israel); Ugalde, C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2015-11-01

A detection technique for high-efficiency measurements of fusion reactions with low-intensity radioactive beams was developed. The technique is based on a Multi-Sampling Ionization Chamber (MUSIC) operating as an active target and detection system, where the ionization gas acts as both target and counting gas. In this way, we can sample an excitation function in an energy range determined by the gas pressure, without changing the beam energy. The detector provides internal normalization to the incident beam and drastically reduces the measuring time. In a first experiment we tested the performance of the technique by measuring the {sup 10,13,15}C+{sup 12}C fusion reactions at energies around the Coulomb barrier.

Role of hexadecapole deformation of projectile 28Si in heavy-ion fusion reactions near the Coulomb barrier

Science.gov (United States)

Kaur, Gurpreet; Hagino, K.; Rowley, N.

2018-06-01

The vast knowledge regarding the strong influence of quadrupole deformation β2 of colliding nuclei in heavy-ion sub-barrier fusion reactions inspires a desire to quest the sensitivity of fusion dynamics to higher order deformations, such as β4 and β6 deformations. However, such studies have rarely been carried out, especially for deformation of projectile nuclei. In this article, we investigated the role of β4 of the projectile nucleus in the fusion of the 28Si+92Zr system. We demonstrated that the fusion barrier distribution is sensitive to the sign and value of the β4 parameter of the projectile, 28Si, and confirmed that the 28Si nucleus has a large positive β4. This study opens an indirect way to estimate deformation parameters of radioactive nuclei using fusion reactions, which is otherwise difficult because of experimental constraints.

Elastic scattering and fusion studies in the reactions $^{10,11}$Be + $^{64}$Zn

CERN Multimedia

2002-01-01

We propose to measure elastic scattering and fusion excitation functions for the reactions $^{10,11}$Be + $^{64}$Zn at 3.1 MeV/u . The aim of the experiment is to investigate possible effects of the halo structure of the $^{11}$Be nucleus on the reaction mechanisms at energy around the Coulomb barrier. For this purpose a comparison with the reaction induced by the $^{10}$Be nucleus is required.

Application of the high-spin isomer beams to the secondary fusion reaction and the measurement of g-factor

International Nuclear Information System (INIS)

Watanabe, H.; Asahi, K.; Kishida, T.; Ueno, H.; Sato, W.; Yoshimi, A.; Kobayashi, Y.; Kameda, D.; Miyoshi, H.; Fukuchi, T.; Wakabayashi, Y.; Sasaki, T.; Kibe, M.; Hokoiwa, N.; Odahara, A.; Cederwall, B.; Lagergren, K.; Podolyak, Zs.; Ishihara, M.; Gono, Y.

2004-01-01

A technique for providing high-spin isomers as probes of the fusion reaction and the measurement of g-factor has been worked out at RIKEN. In the study of the fusion reaction 12 C( 145m Sm,xn) 157-x Er, the γ rays emitted from the fusion-evaporation residue 154 Er have been successfully observed. The nuclear g-factor of the T 1/2 = 28 ns high-spin isomer in 149 Dy has been measured with the γ-ray TDPAD method

Complete and incomplete fusion dynamics of {sup 6,7}Li + {sup 159}Tb reactions near the Coulomb barrier

Energy Technology Data Exchange (ETDEWEB)

Gautam, Manjeet Singh [Thapar University, School of Physics and Materials Science, Patiala (India); Indus Degree College, Department of Physics, Kinana, Jind, Haryana (India); Grover, Neha; Sharma, Manoj K. [Thapar University, School of Physics and Materials Science, Patiala (India)

2017-01-15

The complete fusion (CF) and incomplete fusion (ICF) cross-sections are estimated for {sup 6,} {sup 7}Li + {sup 159}Tb reactions using the energy-dependent Woods-Saxon potential model (EDWSP model) and dynamical cluster-decay model (DCM). The CF data of the {sup 6}Li + {sup 159}Tb({sup 7}Li + {sup 159}Tb) reaction at above barrier energies is suppressed with reference to expectations of the EDWSP model by 25% (20%) which is smaller than the reported data by ∝ 9% (6%). This suppression is correlated with the projectile breakup effect. The projectiles {sup 6,7}Li are loosely bound systems, which may break up into charged fragments prior to reaching the fusion barrier and subsequently one of the fragment is captured by the target leading to the suppression of fusion data at above barrier energies. The sum of CF and ICF, which is termed as total fusion cross-section (TF), removes the discrepancies between theoretical predictions and the above barrier complete fusion data and hence is adequately explained via the EDWSP model over a wide range of energy spread across the Coulomb barrier. In addition to fusion, the decay mechanism of {sup 6}Li + {sup 159}Tb reaction is studied within the framework of the dynamical cluster-decay model (DCM). The breakup of the projectile ({sup 6}Li) in the entrance channel indicates the presence of ICF, which is investigated further using the collective clusterization approach of DCM. The present theoretical analysis suggests that a larger barrier modification is needed to address the fusion data of chosen reactions in the below barrier energy region. (orig.)

The big experimental manual of Free Energy. Cold Fusion - Tesla-Waves - Space-Quantum-Energy - a.o.; Das grosse Freie Energie Experimentier-Handbuch. Kalte Fusion - Tesla-Wellen - Raum-Quanten-Energie - u.v.m.

Energy Technology Data Exchange (ETDEWEB)

Lay, P.; Chmela, H.; Wiedergut, W.

2004-07-01

The main topics of the lectures are: Experiments on cold fusion; Information on space-quantum energy; phenomena of rotating magnets; advanced electrostatic motors; generation of scalar waves; complex rotating fields and levitation from an advanced view; free energy converters. (GL)

Estimation of the {alpha} particles and neutron distribution generated during a fusion reaction; Evaluation de la distribution des particules {alpha} et des neutrons issus de la reaction de fusion

Energy Technology Data Exchange (ETDEWEB)

Dellacherie, S.

1997-12-01

The respective distributions (or density probabilities) of {alpha} particles and neutrons have been modeled using a Monte-Carlo method for the thermonuclear fusion reaction D + T {yields} {alpha} + n + 17.6 MeV. (N.T.).

Light particle revelation on incomplete fusion reactions

International Nuclear Information System (INIS)

Gillibert, A.

1984-01-01

Incomplete fusion reactions have been studied through light particles emission in the reaction 116 Sn + 16 O at 125 MeV (ALICE facility in Orsay). We measured energy angular distributions and correlations between any two of these particles (α particles, protons, neutrons), while γ multiplicity measurements provide us fuller informations. From collected data, the following pictures can be drawn: - the only fast particles observed are α particles, while protons and neutrons seem to come only from statistical evaporation; - outgoing channels where two α particles are emitted cannot be solely explained by the sequential emission of 8 Be → 2α: about half of the cross section proceeds from statistical evaporation of one α particle. Accordingly, 2αxn channels do not necessarily agree with high value of angular momentum in the entrance channel. From the study of experimental results in the yrast plane, we can assign a large width to the angular momentum distribution [fr

A classical approach in simple nuclear fusion reaction 1H2+1H3 using two-dimension granular molecular dynamics model

International Nuclear Information System (INIS)

Viridi, S.; Kurniadi, R.; Waris, A.; Perkasa, Y. S.

2012-01-01

Molecular dynamics in 2-D accompanied by granular model provides an opportunity to investigate binding between nuclei particles and its properties that arises during collision in a fusion reaction. A fully classical approach is used to observe the influence of initial angle of nucleus orientation to the product yielded by the reaction. As an example, a simplest fusion reaction between 1 H 2 and 1 H 3 is observed. Several products of the fusion reaction have been obtained, even the unreported ones, including temporary 2 He 4 nucleus.

Pulsed fusion space propulsion: Computational Magneto-Hydro Dynamics of a multi-coil parabolic reaction chamber

Science.gov (United States)

Romanelli, Gherardo; Mignone, Andrea; Cervone, Angelo

2017-10-01

Pulsed fusion propulsion might finally revolutionise manned space exploration by providing an affordable and relatively fast access to interplanetary destinations. However, such systems are still in an early development phase and one of the key areas requiring further investigations is the operation of the magnetic nozzle, the device meant to exploit the fusion energy and generate thrust. One of the last pulsed fusion magnetic nozzle design is the so called multi-coil parabolic reaction chamber: the reaction is thereby ignited at the focus of an open parabolic chamber, enclosed by a series of coaxial superconducting coils that apply a magnetic field. The field, beside confining the reaction and preventing any contact between hot fusion plasma and chamber structure, is also meant to reflect the explosion and push plasma out of the rocket. Reflection is attained thanks to electric currents induced in conductive skin layers that cover each of the coils, the change of plasma axial momentum generates thrust in reaction. This working principle has yet to be extensively verified and computational Magneto-Hydro Dynamics (MHD) is a viable option to achieve that. This work is one of the first detailed ideal-MHD analysis of a multi-coil parabolic reaction chamber of this kind and has been completed employing PLUTO, a freely distributed computational code developed at the Physics Department of the University of Turin. The results are thus a preliminary verification of the chamber's performance. Nonetheless, plasma leakage through the chamber structure has been highlighted. Therefore, further investigations are required to validate the chamber design. Implementing a more accurate physical model (e.g. Hall-MHD or relativistic-MHD) is thus mandatory, and PLUTO shows the capabilities to achieve that.

Quantum shielding effects on the Gamow penetration factor for nuclear fusion reaction in quantum plasmas

Science.gov (United States)

Lee, Myoung-Jae; Jung, Young-Dae

2017-01-01

The quantum shielding effects on the nuclear fusion reaction process are investigated in quantum plasmas. The closed expression of the classical turning point for the Gamow penetration factor in quantum plasmas is obtained by the Lambert W-function. The closed expressions of the Gamow penetration factor and the cross section for the nuclear fusion reaction in quantum plasmas are obtained as functions of the plasmon energy and the relative kinetic energy by using the effective interaction potential with the WKB analysis. It is shown that the influence of quantum screening suppresses the Sommerfeld reaction factor. It is also shown that the Gamow penetration factor increases with an increase of the plasmon energy. It is also shown that the quantum shielding effect enhances the deuterium formation by the proton-proton reaction in quantum plasmas. In addition, it is found that the energy dependences on the reaction cross section and the Gamow penetration factor are more significant in high plasmon-energy domains.

Fusion rates for hydrogen isotopic molecules of relevance for ''cold fusion''

International Nuclear Information System (INIS)

Szalewicz, K.; Morgan, J.D. III; Monkhorst, H.J.

1989-01-01

In response to the recent announcements of evidence for room-temperature fusion in the electrolysis of D 2 O, we have analyzed how the fusion rate depends on the reduced mass of the fusing nuclei, the effective mass of a ''heavy'' electron, and the degree of vibrational excitation. Our results have been obtained both by accurately solving the Schroedinger equation for the hydrogen molecule and by using the WKB approximation. We find that in light of the reported d-d fusion rate, the excess heat in the experiment by Fleischmann, Pons, and Hawkins [J. Electroanal. Chem. 261, 301 (1989)] is difficult to explain in terms of conventional nuclear processes

Collinear laser spectroscopy on In isotopes from heavy ion fusion reactions

International Nuclear Information System (INIS)

Ulm, G.

1984-07-01

Indium isotopes 107-111 were produced by 16 O-fusion reactions and investigated in a collinear laser geometry. The hyperfine structure and isotopic shifts are measured and the deduced magnetic dipole moments are in agreement with shell model calculations. The nuclear charge radii are determined from the isotopic shifts. (WL)

Cold fusion research in Italy

International Nuclear Information System (INIS)

Scaramuzzi, F.

1993-01-01

This paper summarizes cold fusion (CF) research in Italy. In Italy, many Agencies and Universities are moderately funding research in CF, and the scientists have made a few attempts to coordinate each other, organizing meetings and conferences. However, the activity has been mostly the fruit of the scientists' initiative, and never a coordinated proposal of Agencies and Universities. No position on the scientific validity of the subject has been officially taken and the funds for CF have been rather modest. The investments in Italy on CF, the figure referring to 1992 amounts to about 0.5 million dollars, not including expenses for personnel. A number of about 70 scientists, mostly working part-time, is committed all around the Country in research on CF. The lack of offical commitment and effective support by the Research Agencies and the Universities has not prevented scientists from being quite active in performing research. On the other side, it has to be acknowledged that no formal vetoes have been interposed to the free initiative of scientists in this field: on the contrary, some of the Agencies and Universities have moderately funded such an effort. The quality of the experiments in Italy has been increasingly good, and the results obtained are rather out standing in the general panorama of CF. But it is time to perform a more coordinated effort, keeping in mind that material science aspects, such as the characteristics of the materials used, play a very important role in the development of this topic. Thus, a much more intense effort is required to obtain a more substantial progress in the field. The increasingly convincing results obtained by the whole CF community, and the example of the Japanese Government and Industry, which appear to be determined to promoting CF research, have changed the panorama of CF. These are now signs that also the Italian scientific authorities could consider favouring research in this field in the near future. (J.P.N.)

Low-energy nuclear reaction of the 14N+169Tm system: Incomplete fusion

Science.gov (United States)

Kumar, R.; Sharma, Vijay R.; Yadav, Abhishek; Singh, Pushpendra P.; Agarwal, Avinash; Appannababu, S.; Mukherjee, S.; Singh, B. P.; Ali, R.; Bhowmik, R. K.

2017-11-01

Excitation functions of reaction residues produced in the 14N+169Tm system have been measured to high precision at energies above the fusion barrier, ranging from 1.04 VB to 1.30 VB , and analyzed in the framework of the statistical model code pace4. Analysis of α -emitting channels points toward the onset of incomplete fusion even at slightly above-barrier energies where complete fusion is supposed to be one of the dominant processes. The onset and strength of incomplete fusion have been deduced and studied in terms of various entrance channel parameters. Present results together with the reanalysis of existing data for various projectile-target combinations conclusively suggest strong influence of projectile structure on the onset of incomplete fusion. Also, a strong dependence on the Coulomb effect (ZPZT) has been observed for the present system along with different projectile-target combinations available in the literature. It is concluded that the fraction of incomplete fusion linearly increases with ZPZT and is found to be more for larger ZPZT values, indicating significantly important linear systematics.

Smooth transition from sudden to adiabatic states in heavy-ion fusion reactions at deep-subbarrier incident energies

International Nuclear Information System (INIS)

Takatoshi, Ichikawa; Kouichi, Hagino; Akira, Iwamoto

2011-01-01

We propose a novel extension of the standard coupled-channel (CC) model in order to account for the steep falloff of fusion cross sections at deep-subbarrier incident energies. We introduce a damping factor in the coupling potential in the CC model, simulating smooth transitions from sudden to adiabatic states in deep- subbarrier fusion reactions. The CC model extended with the damping factor can reproduce well not only the steep falloff of the fusion cross section but also the saturation of the logarithmic derivatives for the fusion cross sections at deep-subbarrier energies for the 16 O+ 208 Pb, 64 Ni+ 64 Ni, and 58 Ni+ 58 Ni reactions at the deep-subbarrier energies. The important point in our model is that the transition takes place at different places for each Eigen channel. We conclude that the smooth transition from the two-body to the adiabatic one-body potential is responsible for the steep falloff of the fusion cross section

Fusion and direct reactions for strongly and weakly bound projectiles

International Nuclear Information System (INIS)

Hugi, M.; Lang, J.; Mueller, R.; Ungricht, E.; Bodek, K.; Jarczyk, L.; Kamys, B.; Magiera, A.; Strzalkowski, A.; Willim, G.

1981-01-01

The interaction of 6 Li, 9 Be and 12 C projectiles with a 28 Si target was investigated by measuring the angular distributions of the elasitcally scattered projectiles and of the emitted protons, deuterons and α-particles. The experiment was perfomred in order to deduce direct and compound nucleus process contributions to the total reaction cross section and to study the influence of the projectile structure on the relative importance of these two mechanisms. Optical model parameters and therefore the total reaction cross section are strongly influenced by the binding energy of the projectile. The parameters of the Glas-Mosel describing the fusion reaction vary smoothly with the atomic number. In the system 9 B + 28 Si around 50% of all reactions are direct processes even at energies near the Coulomb barrier, whereas in the other systeme the direct part amounts to 15% ( 12 C) and 30% ( 6 Li) only. (orig.)

Fusion dynamics of 2020Ne + 20882Pb reaction using static and energy dependent Woods-Saxon potential

International Nuclear Information System (INIS)

Gautam, Manjeet Singh; Kaur, Amandeep; Sharma, Manoj K.

2015-01-01

The present work compares the theoretical predictions based on static Woods-Saxon potential and the EDWSP model along with one dimensional Wong formula. For 20 20 Ne + 208 82 Pb reaction, the theoretical calculations obtained by using static Woods-Saxon potential are substantially smaller than that of experimental data at below barrier energies and explain the fusion data at above barrier energies only. On the other hand, the EDWSP model based calculations adequately describe the observed fusion enhancement of 20 20 Ne + 208 82 Pb reaction in whole range of energy spread across the Coulomb barrier. Furthermore, a wide range of the diffuseness parameter ranging from 0.96 fm to 0.85 fm is required to address the sub-barrier fusion data

Fusion and quasifission studies for the 40Ca+186W,192Os reactions

Science.gov (United States)

Prasad, E.; Hinde, D. J.; Williams, E.; Dasgupta, M.; Carter, I. P.; Cook, K. J.; Jeung, D. Y.; Luong, D. H.; Palshetkar, C. S.; Rafferty, D. C.; Ramachandran, K.; Simenel, C.; Wakhle, A.

2017-09-01

Background: All elements above atomic number 113 have been synthesized using hot fusion reactions with calcium beams on statically deformed actinide target nuclei. Quasifission and fusion-fission are the two major mechanisms responsible for the very low production cross sections of superheavy elements. Purpose: To achieve a quantitative measurement of capture and quasifission characteristics as a function of beam energy in reactions forming heavy compound systems using calcium beams as projectiles. Methods: Fission fragment mass-angle distributions were measured for the two reactions 40Ca+186W and 40C+192Os, populating 226Pu and 232Cm compound nuclei, respectively, using the Heavy Ion Accelerator Facility and CUBE spectrometer at the Australian National University. Mass ratio distributions, angular distributions, and total fission cross sections were obtained from the experimental data. Simulations to match the features of the experimental mass-angle distributions were performed using a classical phenomenological approach. Results: Both 40Ca+186W and 40C+192Os reactions show strong mass-angle correlations at all energies measured. A maximum fusion probability of 60 -70 % is estimated for the two reactions in the energy range of the present study. Coupled-channels calculations assuming standard Woods-Saxon potential parameters overpredict the capture cross sections. Large nuclear potential diffuseness parameters ˜1.5 fm are required to fit the total capture cross sections. The presence of a weak mass-asymmetric quasifission component attributed to the higher angular momentum events can be reproduced with a shorter average sticking time but longer mass-equilibration time constant. Conclusions: The deduced above-barrier capture cross sections suggest that the dissipative processes are already occurring outside the capture barrier. The mass-angle correlations indicate that a compact shape is not achieved for deformation aligned collisions with lower capture barriers

Incomplete fusion studies

International Nuclear Information System (INIS)

Singh, B.P.

2011-01-01

In order to study the incomplete fusion reaction dynamics at energies ≅ 4-7 MeV/nucleon, several experiments have been carried out using accelerator facilities available in India. The measurements presented here cover a wide range of projectile-target combinations and enhance significantly our knowledge about incomplete fusion reaction dynamics. Here, the three sets of measurements have been presented; (i) excitation functions, (ii) forward recoil range distributions and (iii) the spin distributions. The first evidence of these reactions has been obtained from the measurement and analysis of excitation functions for xn/αxn/2αxn-channels. The measured excitation functions have been analyzed within the framework of compound nucleus model. The results obtained indicate the occurrence of fusion incompleteness at low beam energies. However, in order to determine the relative contribution of complete and incomplete fusion reaction processes, the recoil range distributions of the heavy residues have also been measured and analyzed within the framework of breakup fusion model which confirmed the fusion incompleteness in several heavy ion reactions involving α-emitting reaction channels. Further, in order to study the role of l-values in these reactions the spin distributions of the residues populated in case of complete and incomplete channels have been measured and are found to be distinctly different. The analysis of the data on spin distribution measurements indicate that the mean values of driving input angular momenta associated with direct-α-emitting (incomplete fusion) channels are higher than that observed for fusion-evaporation xn or α-emitting (complete fusion) channels, and is found to increase with direct α-multiplicity in the forward cone. One of the important conclusions drawn in the present work is that, there is significant incomplete fusion contribution even at energies slightly above the barrier. Further, the projectile structure has been found to

Fusability and fissionability in 86Kr induced reactions near and below the fusion barrier

International Nuclear Information System (INIS)

Reisdorf, W.; Hessberger, F.P.; Hildenbrand, K.D.; Hofmann, S.; Muenzenberg, G.; Schmidt, K.H.; Schneider, W.F.W.; Suemmerer, K.; Wirth, G.; Kratz, J.V.; Schlitt, K.; Sahm, C.C.

1985-04-01

Evaporation-residue excitation functions for the reactions 86 Kr + sup(70,76)Ge, sup(92,100)Mo, sup(99,102,104)Ru have been measured using activation methods and the velocity filter SHIP. The data span the region from well below the fusion barrier up to and beyond the energy where limitation by fission competition takes place. The data are shown to be compatible with the concept of complete fusion followed by the statistical decay of the equilibrated compound nucleus. Information on both the fusion probability at and below the fusion threshold and the fissionability of the compound nuclei formed is extracted. The model dependence of the extracted fission barriers is discussed in detail. In analogy to studies involving lighter projectiles, strong correlations between the low-energy nuclear-structure properties of the nuclei and the subbarrier fusion probability are found. A relative shift of the fusion barrier to higher energies, that increases with the number of valence neutrons in the target nuclei, is observed. (orig.)

Effects on nuclear fusion reaction on diffusion and thermal conduction in a magnetoplasma

International Nuclear Information System (INIS)

Sakai, Kazuo; Aono, Osamu.

1976-12-01

In spite of the well spread belief in the field of irreversible thermodynamics, vectorial phenomena couple thermodynamically with the scalar phenomena. Transport coefficients concerning the diffusion and the thermal conduction across a strong magnetic field are calculated in the presence of the deuteron-triton fusion reaction on the basis of the gas kinetic theory. When the reaction takes place, the diffusion increases and the thermal conduction decreases. Effects of the reaction exceed those of the Coulomb collision as the temperature is high enough. (auth.)

Study of the role of complete fusion in the reaction of 48Ca and 56Fe with cerium and terbium

International Nuclear Information System (INIS)

Morrissey, D.J.

1978-05-01

48 Ca and 56 Fe beams from the Super HILAC accelerator were used to irradiate thick metal foils of cerium and terbium. Product gamma ray activities were detected offline and individual products were identified by half-life, gamma ray energy and gamma ray abundances. The production cross sections were iteratively fit to charge and mass dispersions to allow correction for parent decay and calculation of mass yields. From the mass yield curves contributions from quasielastic transfer, deep inelastic transfer and complete fusion reaction mechanisms were interred. Complete fusion was made up on contributions from both evaporation residue and fusion-fission products for the 48 Ca induced reactions. However, only fusion-fission products were detected in the 56 Fe induced reactions. Critical angular momenta for fusion were found to be 82 +- 8 h for 48 Ca + 159 Tb and 34 +- 5 h for 56 Fe + 140 Ce, which can be compared with 53 +- 8 h for 12 C + 197 Au (Natowitz, 1970) and 86 +- 5 h for 40 Ar + 165 Ho (Hanappe, 1973). All of these reactions lead to essentially the same compound nucleus and seem to show the dramatic decline in complete fusion for heavy ions larger than 40 Ar. The prediction of this decline was found to be beyond the model calculations of Bass and the critical distance approach of Glas and Mosel

Reaction-rate coefficients, high-energy ions slowing-down, and power balance in a tokamak fusion reactor plasma

International Nuclear Information System (INIS)

Tone, Tatsuzo

1978-07-01

Described are the reactivity coefficient of D-T fusion reaction, slowing-down processes of deuterons injected with high energy and 3.52 MeV alpha particles generated in D-T reaction, and the power balance in a Tokamak reactor plasma. Most of the results were obtained in the first preliminary design of JAERI Experimental Fusion Reactor (JXFR) driven with stationary neutral beam injection. A manual of numerical computation program ''BALTOK'' developed for the calculations is given in the appendix. (auth.)

Energy dependence of fusion evaporation-residue cross sections in the 28Si+28Si reaction

International Nuclear Information System (INIS)

Vineyard, M.F.; Bauer, J.S.; Gosdin, C.H.; Trotter, R.S.; Kovar, D.G.; Beck, C.; Henderson, D.J.; Janssens, R.V.F.; Wilkins, B.D.; Rosner, G.; Chowdhury, P.; Ikezoe, H.; Kuhn, W.; Kolata, J.J.; Hinnefeld, J.D.; Maguire, C.F.; Mateja, J.F.; Prosser, F.W.; Stephans, G.S.F.

1990-01-01

Velocity distributions of mass-identified evaporation residues produced in the 28 Si+ 28 Si reaction have been measured at bombarding energies of 174, 215, 240, 309, 397, and 452 MeV using time-of-flight techniques. These distributions were used to identify evaporation residues and to separate the complete-fusion and incomplete-fusion components. Angular distributions and total cross sections were extracted at all six bombarding energies. The complete-fusion evaporation-residue cross sections and the deduced critical angular momenta are compared with lower energy data and the predictions of existing models

Application of SSNTDs for measurements of fusion reaction products in high-temperature plasma experiments

Energy Technology Data Exchange (ETDEWEB)

Malinowska, A., E-mail: a.malinowska@ipj.gov.p [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Szydlowski, A.; Malinowski, K. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Sadowski, M.J. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Institute of Plasma Physics and Laser Microfusion (IPPLM), 00-908 Warsaw (Poland); Zebrowski, J. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Scholz, M.; Paduch, M.; Zielinska, E. [Institute of Plasma Physics and Laser Microfusion (IPPLM), 00-908 Warsaw (Poland); Jaskola, M.; Korman, A. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland)

2009-10-15

The paper describes the application of SSNTDs of the PM-355 type to diagnostics of reaction products emitted from high-temperature deuterium plasmas produced in Plasma Focus (PF) facilities. Acceleration processes occurring in plasma lead often to the generation of high-energy ion beams. Such beams induce nuclear reactions and contribute to the emission of fast neutrons, fusion protons and alpha particles from PF discharges with a deuterium gas. Ion measurements are of primary importance for understanding the mechanisms of the physical processes which drive the charged-particle acceleration. The main aim of the present studies was to perform measurements of spatial- and energy-distributions of fusion-reaction protons (about 3 MeV) within a PF facility. Results obtained from energy measurements were compared with the proton-energy spectra computed theoretically. The protons were measured by means of a set of ion pinhole cameras equipped with PM-355 detectors, which were placed at different angles relative to the electrode axis of the PF facility.

A 1.5--4 Kelvin detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogens fuels

International Nuclear Information System (INIS)

Alexander, N.; Barden, J.; Fan, Q.; Honig, A.

1990-01-01

A compact cold-transfer apparatus for engaging and retrieving samples at liquid helium temperatures (1.5--4K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target-shells containing highly spin-polarized deuterons in solid HD or D 2 for inertially confined fusion (ICF) experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed. 9 refs., 6 figs

Coupled-channels analyses for 9,11Li + 208Pb fusion reactions with multi-neutron transfer couplings

Science.gov (United States)

Choi, Ki-Seok; Cheoun, Myung-Ki; So, W. Y.; Hagino, K.; Kim, K. S.

2018-05-01

We discuss the role of two-neutron transfer processes in the fusion reaction of the 9,11Li + 208Pb systems. We first analyze the 9Li + 208Pb reaction by taking into account the coupling to the 7Li + 210Pb channel. To this end, we assume that two neutrons are directly transferred to a single effective channel in 210Pb and solve the coupled-channels equations with the two channels. By adjusting the coupling strength and the effective Q-value, we successfully reproduce the experimental fusion cross sections for this system. We then analyze the 11Li + 208Pb reaction in a similar manner, that is, by taking into account three effective channels with 11Li + 208Pb, 9Li + 210Pb, and 7Li + 212Pb partitions. In order to take into account the halo structure of the 11Li nucleus, we construct the potential between 11Li and 208Pb with a double folding procedure, while we employ a Woods-Saxon type potential with the global Akyüz-Winther parameters for the other channels. Our calculation indicates that the multiple two-neutron transfer process plays a crucial role in the 11Li + 208Pb fusion reaction at energies around the Coulomb barrier.

Indirect Study of the 16O+16O Fusion Reaction Toward Stellar Energies by the Trojan Horse Method

Directory of Open Access Journals (Sweden)

Hayakawa S.

2016-01-01

Full Text Available The 16O+16O fusion reaction is important in terms of the explosive oxygen burning process during late evolution stage of massive stars as well as understanding of the mechanism of low-energy heavy-ion fusion reactions. We aim to determine the excitation function for the most major exit channels, α+28Si and p+31P, toward stellar energies indirectly by the Trojan Horse Method via the 16O(20Ne, α28Siα and 16O(20Ne, p31Pα three-body reactions. We report preliminary results involving reaction identification, and determination of the momentum distribution of α-16O intercluster motion in the projectile 20Ne nucleus.

The controlled thermonuclear fusion

International Nuclear Information System (INIS)

Barre, Bertrand

2014-01-01

After some generalities on particle physics, and on fusion and fission reactions, the author outlines that the fission reaction is easier to obtain than the fusion reaction, evokes the fusion which takes place in stars, and outlines the difficulty to manage and control this reaction: one of its application is the H bomb. The challenge is therefore to find a way to control this reaction and make it a steady and continuous source of energy. The author then presents the most promising way: the magnetic confinement fusion. He evokes its main issues, the already performed experiments (tokamak), and gives a larger presentation of the ITER project. Then, he evokes another way, the inertial confinement fusion, and the two main experimental installations (National Ignition Facility in Livermore, and the Laser Megajoule in Bordeaux). Finally, he gives a list of benefits and drawbacks of an industrial nuclear fusion

Microscopic calculation of the molecular-nuclear D+D → sup(3)He+n and D+D → sup(3)H+p reactions at close to zero energies

International Nuclear Information System (INIS)

Frederico, T.; Groote, J.J. de; Hornos, J.E.; Hussein, M.S.

1990-11-01

Microscopic calculations of the astrophysically interesting reactions D+D→sup(3)He+n and D+D→sup(3)H+p are performed using nuclear reaction theory and Born-Oppenheimer type molecular calculation of the D+D initial stage. The sensitivity of the fusion rate to the behaviour of the D+D wave function at close to zero separation is assessed. Relevance of the results to the cold fusion problem is discussed. (author)

A comparison of the radiological impact of energy production by fission and fusion reactions

International Nuclear Information System (INIS)

Rancillac, F.; Despres, A.

1990-04-01

The impacts of respectively a light water reactor and a planned fusion reactor, for which tritium-deuterium fusion reactions will act as energy source have been compared. The comparison is made on the basis of a generated capacity of 1 GWe.year, using the following criteria: fuel inventories, radioactive releases, collective effective dose equivalent commitments to the public and the volume of wastes. The accidental risk is not introduced. Fusion reactor parameters are still subject to uncertainties, which prevent accurate quantification of radionuclide releases (tritium apart) from the nuclear plant. Only orders of magnitude extrapolated from values for the NET tokamak are given. Despite these uncertainties, it would seem more interesting, from the dosimetric point of view, to use fusion reactors to produce electricity, although problems of radioactive releases, handling and long-term storage of radioactive waste would remain. Fusion reactors also generate generate high-level wastes with long-term exposure rates that are lower than those of light water reactors [fr

On a possibility of cold fusion in deuterium-saturated YBa2Cu3O7-x ceramics in superconducting state

International Nuclear Information System (INIS)

Lipson, A.G.; Sakov, D.M.; Toporov, Yu.P.; Gromov, V.V.; Deryagin, B.V.

1991-01-01

A possibility to generate neutrons by deuterated YBa 2 Cu 3 O 7-x ceramics in superconducting (T c ) and normal (T>T c ) states is studied. The presented data points to a relationship between the processes of cold nuclear fusion and high-temperature superconductivity in YBa 2 Cu 3 O 7-x pellets deuterated at T c (77< T<90 K)

Suprathermal fusion reactions in laser-imploded D-T pellets. Applicability to pellet diagnosis and necessity of nuclear data

International Nuclear Information System (INIS)

Tabaru, Y.; Nakao, Y.; Kudo, K.; Nakashima, H.

1995-01-01

The suprathermal fusion reaction is examined on the basis of coupled transport/hydrodynamic calculation. We also calculate the energy spectrum of neutrons bursting from DT pellet. Because of suprathermal fusion and rapid pellet expansion, these neutrons contain fast components whose maximum energy reachs about 40 MeV. The pellet ρR diagnosis by the detection of suprathermal fusion neutrons is discussed. (author)

Dynamics of Db isotopes formed in reactions induced by 238U, 248Cm, and 249Bk across the Coulomb barrier

Science.gov (United States)

Kaur, Gurjit; Sandhu, Kirandeep; Kaur, Amandeep; Sharma, Manoj K.

2018-05-01

The dynamical cluster decay model is employed to investigate the decay of *265Db and *267Db nuclei, formed in the 27Al+238U , 18O+249Bk , and 19F+248Cm hot fusion reactions at energies around the Coulomb barrier. First, the fission dynamics of the 27Al+238U reaction is explored by investigating the fragmentation and preformation yield of the reaction. The symmetric mass distribution of the fission fragments is observed for *265Db nucleus, when static β2 i deformations are used within hot optimum orientation approach. However, the mass split gets broaden for the use of β2 i-dynamical hot configuration of the fragments and becomes clearly asymmetric for the cold-static-deformed approach. Within the application of cold orientations of fragments, a new fission channel is observed at mass asymmetry η =0.29 . In addition to 238U-induced reaction, the work is carried out to address the fission and neutron evaporation cross sections of *267Db nucleus formed via 19F+248Cm and 18O+249Bk reactions, besides a comprehensive analysis of fusion and capture processes. Higher fusion cross sections and compound nucleus formation probabilities (PCN) are obtained for the 18O+249Bk reaction, as larger mass asymmetry in the entrance channel leads to reduced Coulomb factor. Finally, the role of sticking (IS) and nonsticking (INS) moments of inertia is analyzed for the 4 n and 5 n channels of *267Db nuclear system.

Low Energy Nuclear Reactions: 2007 Update

Science.gov (United States)

Krivit, Steven B.

2007-03-01

This paper presents an overview of low energy nuclear reactions, a subset of the field of condensed matter nuclear science. Condensed matter nuclear science studies nuclear effects in and/or on condensed matter, including low energy nuclear reactions, an entirely new branch of science that gained widespread attention and notoriety beginning in 1989 with the announcement of a previously unrecognized source of energy by Martin Fleischmann and Stanley Pons that came to be known as cold fusion. Two branches of LENR are recognized. The first includes a set of reactions like those observed by Fleischmann and Pons that use palladium and deuterium and yield excess heat and helium-4. Numerous mechanisms have been proposed to explain these reactions, however there is no consensus for, or general acceptance of, any of the theories. The claim of fusion is still considered speculative and, as such, is not an ideal term for this work. The other branch is a wide assortment of nuclear reactions that may occur with either hydrogen or deuterium. Anomalous nuclear transmutations are reported that involve light as well as heavy elements. The significant questions that face this field of research are: 1) Are LENRs a genuine nuclear reaction? 2) If so, is there a release of excess energy? 3) If there is, is the energy release cost-effective?

Calculations of Excitation Functions of Some Structural Fusion Materials for ( n, t) Reactions up to 50 MeV Energy

Science.gov (United States)

Tel, E.; Durgu, C.; Aktı, N. N.; Okuducu, Ş.

2010-06-01

Fusion serves an inexhaustible energy for humankind. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. Tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. So, the working out the systematics of ( n, t) reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. In this study, ( n, t) reactions for some structural fusion materials such as 27Al, 51V, 52Cr, 55Mn, and 56Fe have been investigated. The new calculations on the excitation functions of 27Al( n, t)25Mg, 51V( n, t)49Ti, 52Cr( n, t)50V, 55Mn( n, t)53Cr and 56Fe( n, t)54Mn reactions have been carried out up to 50 MeV incident neutron energy. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the new evaluated the geometry dependent hybrid model, hybrid model and the cascade exciton model. Equilibrium effects are calculated according to the Weisskopf-Ewing model. Also in the present work, we have calculated ( n, t) reaction cross-sections by using new evaluated semi-empirical formulas developed by Tel et al. at 14-15 MeV energy. The calculated results are discussed and compared with the experimental data taken from the literature.

Electrochemical 'cold fusion' trials at IPP Garching

International Nuclear Information System (INIS)

Bosch, H.S.; Gernhardt, J.; Karger, F.; Perchermeier, J.; Wurden, G.A.

1989-07-01

Following the report of Fleischmann and Pons, we (The Bavarian Bubble Bottle Team) have attempted to reproduce their claims of cold nuclear fusion, and failed. We note that our measurements would not be able to detect neutrons at the level of Jones et al. Three electrolytic cell experiments were conducted using palladium cathodes and Platinum anodes, in a 0.1 Molar solution of LiD in heavy water, without any signs of neutrons, tritium or gammas above backgrounds, and within ±0.3 Watt accuracy calorimetry, no excess heating. Excess heating at the levels of F P would have been easily detected, if present. Intrinsic tritium, differing from each D 2 O bottle tested, was however observed. The longest duration experiment ran for 21 days, and was an attempt to duplicate the large 'melting incident' of F P . This was terminated on April 28, 1989, by throwing the vacuum-cast 22 gram, deuterium-loaded palladium cathode directly into liquid nitrogen, immediately next to a bare BF 3 counter (backed by 25 cm of moderator), in order to attempt one of the Italian ENEA neutron production variants. No neutrons above backgrounds were seen, while counting for one hour, and also none while the piece warmed to room temperature over the next hour. Post mortem analysis of the darkened, hardened Pd piece showed large crystal grains (up to 2 mmx2 mm), and continuing evolution of gas bubbles at the grain boundaries even four days after the experiment was ended. Eight weeks after loading, the catalytically active palladium piece continued to create heavy water (with exposure to oxygen in the air). (orig.)

Absorption-Fluctuation Theorem for Nuclear Reactions: Brink-Axel, Incomplete Fusion and All That

International Nuclear Information System (INIS)

Hussein, M. S.

2008-01-01

We discuss the connection between absorption, averages and fluctuations in nuclear reactions. The fluctuations in the entrance channel result in the compound-nucleus Hauser-Feshbach cross section, and the fluctuations in the intermediate channels result in modifications of multistep reaction cross sections, while the fluctuations in the final channel result in hybrid cross sections that can be used to describe incomplete fusion reactions. We discuss the latter in detail and comment on the validity of the assumptions used in the development of the Surrogate method. We also discuss the theory of multistep reactions with regards to intermediate state fluctuations and the energy dependence and non-locality of the intermediate-channel optical potentials

The IGNITEX fusion project

International Nuclear Information System (INIS)

Carrera, R.

1987-01-01

The author discusses the recently proposed fusion ignition experiment, IGNITEX. He emphasizes the basic ideas of this concept rather than the specific details of the physics and engineering aspects of the experiment. This concept is a good example of the importance of maintaining an adequate balance between the basic scientific progress in fusion physics and the new technologies that are becoming available in order to make fusion work. The objective of the IGNITEX project is to produce and control ignited plasmas for scientific study in the simplest and least expensive way possible. Being able to study this not-yet-produced regime of plasma operation is essential to fusion research. Two years after the fission nuclear reaction was discovered, a non-self-sustained fission reaction was produced in a laboratory, and in one more year a self-sustained reaction was achieved at the University of Chicago. However, after almost forty years of fusion research, a self-sustained fusion reaction has yet not been produced in a laboratory experiment. This fact indicates the greater difficulty of the fusion experiment. Because of the difficulty involved in the production of a self-sustained fusion reaction, it is necessary to propose such an experiment with maximum ignition margins, maximum simplicity, and minimum financial risk

Inertial confinement fusion reaction chamber and power conversion system study. Final report

International Nuclear Information System (INIS)

Maya, I.; Schultz, K.R.; Bourque, R.F.

1985-10-01

This report summarizes the results of the second year of a two-year study on the design and evaluation of the Cascade concept as a commercial inertial confinement fusion (ICF) reactor. We developed a reactor design based on the Cascade reaction chamber concept that would be competitive in terms of both capital and operating costs, safe and environmentally acceptable in terms of hazard to the public, occupational exposure and radioactive waste production, and highly efficient. The Cascade reaction chamber is a double-cone-shaped rotating drum. The granulated solid blanket materials inside the rotating chamber are held against the walls by centrifugal force. The fusion energy is captured in a blanket of solid carbon, BeO, and LiAlO 2 granules. These granules are circulated to the primary side of a ceramic heat exchanger. Primary-side granule temperatures range from 1285 K at the LiAlO 2 granule heat exchanger outlet to 1600 K at the carbon granule heat exchanger inlet. The secondary side consists of a closed-cycle gas turbine power conversion system with helium working fluid, operating at 1300 K peak outlet temperature and achieving a thermal power conversion efficiency of 55%. The net plant efficiency is 49%. The reference design is a plant producing 1500 MW of D-T fusion power and delivering 815 MW of electrical power for sale to the utility grid. 88 refs., 44 figs., 47 tabs

Comparative studies for different proximity potentials applied to sub-barrier fusion reactions

Energy Technology Data Exchange (ETDEWEB)

Zhang, G.L. [Beihang University, School of Physics and Nuclear Energy Engineering, Beijing (China); Beihang University, Key Laboratory of Micro-Nano Measurement-Manipulation and Physics (Ministry of Education), Beijing (China); Qu, W.W. [Medical College of Soochow University, School of Radiation Medicine and Protection, Soochow (China); Guo, M.F.; Qian, J.Q. [Beihang University, School of Physics and Nuclear Energy Engineering, Beijing (China); Zhang, H.Q. [China Institute of Atomic Energy, Beijing (China); Wolski, R. [Henryk Niewodniczanski Institute of Nuclear Physics PAS, Cracow (Poland)

2016-02-15

Coulomb barrier heights calculated by using 14 different versions of proximity potentials are studied and applied for experimental data of fusion in terms of a recently proposed energy scaling approach. The results show that the descriptions of proximity potentials 77 and 88 for the barrier heights seem to be closest to the values required by the systematics. On the basis of proximity potential 77, the parameterized formulas of the barrier height and radius are obtained. These formulas can calculate the barrier positions and barrier heights reasonably well within the error, respectively. Thus it provides a simple and direct way to calculate the barrier positions and barrier heights for heavy-ion fusion reactions. (orig.)

A survey of selected neutron-activation reactions with short-lived products of importance to fusion reactor technology

International Nuclear Information System (INIS)

Ward, R.C.; Gomes, I.C.; Smith, D.L.

1994-11-01

The status of the cross sections for production of short-lived radioactivities in the intense high-energy neutron fields associated with D-T fusion reactors is investigated. The main concerns relative to these very radioactive isotopes are with radiation damage to sensitive components such as superconducting magnets, the decay-heat problem and the safety of personnel during operation of the facility. The present report surveys the status of nuclear data required to assess these problems. The study is limited to a few high-priority nuclear reactions which appear to be of critical concern in this context. Other reactions of lesser concern are listed but are not treated in the present work. Among the factors that were considered in defining the relevant reactions and setting priorities are: quantities of the elemental materials in a fusion reactor, isotopic abundances within elemental categories, the decay properties of the induced radioactive byproducts, the reaction cross sections, and the nature of the decay radiations. Attention has been focused on radioactive species with half lives in the range from about 1 second to 15 minutes. Available cross-section and reaction-product decay information from the literature has been compiled and included in the report. Uncertainties have been estimated by examining several sets of experimental as well as evaluated data. Comments on the general status of data for various high-priority reactions are offered. On the basis of this investigation, it has been found that the nuclear data are in reasonably good shape for some of the most important reactions but are unacceptable for others. Based on this investigation, the reactions which should be given the greatest attention are: 16 O(n,p) 16 N, 55 Mn(n,p) 55 Cr, 57 Fe(n,p) 57 Mn, 186 W(n,2n) 185m W, and 207 Pb(n,n') 207m Pb. However, the development of fusion power would benefit from an across-the-board refinement in these nuclear data so that a more accurate quantitative

Experimental Cross Sections for Reactions of Heavy Ions and ²⁰⁸Pb, ²⁰⁹Bi, ²³⁸U, and ²⁴⁸Cm Targets

Energy Technology Data Exchange (ETDEWEB)

Patin, Joshua Barnes [Univ. of California, Berkeley, CA (United States)

2002-01-01

The study of the reactions between heavy ions and ²⁰⁸Pb, ²⁰⁹Bi, ²³⁸U, and ²⁴⁸Cm Cm targets was performed to look at the differences between the cross sections of hot and cold fusion reactions. Experimental cross sections were compared with predictions from statistical computer codes to evaluate the effectiveness of the computer code in predicting production cross sections. Hot fusion reactions were studied with the MG system, catcher foil techniques and the Berkeley Gas-filled Separator (BGS). 3n- and 4n-exit channel production cross sections were obtained for the ²³⁸U(¹⁸O,xn)^256-xFm, ²³⁸U(²²Ne,xn)^260-xNo, and ²⁴⁸Cm(¹⁵N,xn)^263-xLr reactions and are similar to previous experimental results. The experimental cross sections were accurately modeled by the predictions of the HIVAP code using the Reisdorf and Schaedel parameters and are consistent with the existing systematics of 4n exit channel reaction products. Cold fusion reactions were examined using the BGS. The ⁴⁸Pb(²³⁸Ca,xn)^256-xNo, ²⁰⁸Pb(⁵⁰Ti,xn)^258-xRf, ²⁰⁸Pb(⁵¹V,xn)^259-xDb, ⁵⁰Bi(²³⁸Ti,xn)^259-xDb, and ²⁰⁹Bi(⁵¹V,xn)^260-xSg reactions were studied. The experimental production cross sections are in agreement with the results observed in previous experiments. It was necessary to slightly alter the Reisdorf and Schaedel parameters for use in the HIVAP code in order to more accurately model the experimental data. The cold fusion experimental results are in agreement with current 1n- and 2n-exit channel systematics.

Low-energy d+d fusion reactions via the Trojan Horse Method

Energy Technology Data Exchange (ETDEWEB)

Tumino, A., E-mail: tumino@lns.infn.it [Laboratori Nazionali del Sud, INFN, and Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); Universita degli Studi di Enna ' Kore' , Enna (Italy); Spitaleri, C. [Laboratori Nazionali del Sud, INFN, and Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); Mukhamedzhanov, A.M. [Cyclotron Institute Texas A and M University, College Station, TX (United States); Typel, S. [Excellence Cluster Universe, Technische Universitaet Muenchen, Garching (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH - Theorie, Darmstadt (Germany); Aliotta, M. [School of Physics and Astronomy, University of Edinburgh, Edinburgh, Scotland (United Kingdom); Scottish Universities Physics Alliance (United Kingdom); Burjan, V. [Nuclear Physics Institute of ASCR, Rez near Prague (Czech Republic); Gimenez del Santo, M. [Departamento de Fisica Nuclear, Universitade de Sao Paulo, Sao Paulo (Brazil); Kiss, G.G. [Laboratori Nazionali del Sud, INFN, and Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); ATOMKI, Debrecen (Hungary); Kroha, V.; Hons, Z. [Nuclear Physics Institute of ASCR, Rez near Prague (Czech Republic); La Cognata, M.; Lamia, L. [Laboratori Nazionali del Sud, INFN, and Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); Mrazek, J. [Nuclear Physics Institute of ASCR, Rez near Prague (Czech Republic); Pizzone, R.G. [Laboratori Nazionali del Sud, INFN, and Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); Piskor, S. [Nuclear Physics Institute of ASCR, Rez (Czech Republic); Rapisarda, G.G.; Romano, S.; Sergi, M.L.; Sparta, R. [Laboratori Nazionali del Sud, INFN, and Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy)

2011-06-06

The bare nucleus S(E) factors for the {sup 2}H(d,p){sup 3}H and {sup 2}H(d,n){sup 3}He reactions have been measured for the first time via the Trojan Horse Method off the proton in {sup 3}He from 1.5 MeV down to 2 keV. This range overlaps with the relevant region for Standard Big Bang Nucleosynthesis as well as with the thermal energies of future fusion reactors and deuterium burning in the Pre-Main-Sequence phase of stellar evolution. This is the first pioneering experiment in quasi free regime where the charged spectator is detected. Both the energy dependence and the absolute value of the S(E) factors deviate by more than 15% from available direct data with new S(0) values of 57.4{+-}1.8 MeVb for {sup 3}H+p and 60.1{+-}1.9 MeVb for {sup 3}He+n. None of the existing fitting curves is able to provide the correct slope of the new data in the full range, thus calling for a revision of the theoretical description. This has consequences in the calculation of the reaction rates with more than a 25% increase at the temperatures of future fusion reactors.

Low-energy d+d fusion reactions via the Trojan Horse Method

International Nuclear Information System (INIS)

Tumino, A.; Spitaleri, C.; Mukhamedzhanov, A.M.; Typel, S.; Aliotta, M.; Burjan, V.; Gimenez del Santo, M.; Kiss, G.G.; Kroha, V.; Hons, Z.; La Cognata, M.; Lamia, L.; Mrazek, J.; Pizzone, R.G.; Piskor, S.; Rapisarda, G.G.; Romano, S.; Sergi, M.L.; Sparta, R.

2011-01-01

The bare nucleus S(E) factors for the 2 H(d,p) 3 H and 2 H(d,n) 3 He reactions have been measured for the first time via the Trojan Horse Method off the proton in 3 He from 1.5 MeV down to 2 keV. This range overlaps with the relevant region for Standard Big Bang Nucleosynthesis as well as with the thermal energies of future fusion reactors and deuterium burning in the Pre-Main-Sequence phase of stellar evolution. This is the first pioneering experiment in quasi free regime where the charged spectator is detected. Both the energy dependence and the absolute value of the S(E) factors deviate by more than 15% from available direct data with new S(0) values of 57.4±1.8 MeVb for 3 H+p and 60.1±1.9 MeVb for 3 He+n. None of the existing fitting curves is able to provide the correct slope of the new data in the full range, thus calling for a revision of the theoretical description. This has consequences in the calculation of the reaction rates with more than a 25% increase at the temperatures of future fusion reactors.

Spin distribution studies: a sensitive probe for in-complete fusion reaction dynamics

International Nuclear Information System (INIS)

Singh, Pushpendra P.; Singh, B.P.; Unnati; Sharma, Bhavna; Sharma, Manoj Kumar; Singh, D.; Afzal Ansari, M.; Prasad, R.; Rakesh Kumar; Golda, K.S.; Muralithar, S.; Singh, R.P.; Bhowmik, R.K.; Bhardwaj, H.D.

2006-01-01

With the view to get the conclusive information on critical angular momentum involvement for various degrees of incomplete fusion, an in-beam particle-gamma coincidence experiment has been performed in 16 O + 169 Tm system at ≅ 5.6 MeV/nucleon. Spin distributions for different reaction products have been measured by studying the relative population of different levels in a rotational band

Influence of hexadecapole deformations of the nuclear shape of subbarrier fusion reactions

International Nuclear Information System (INIS)

Fernandez Niello, J.

1989-01-01

A systematic study of the contribution of hexadecapole deformations to the enhancement of subbarrier fusion cross reactions is carried out. The analysis is based on calculations that cover the full range of values of hexadecapole deformations found in actual nuclear systems. The interplay of this shape degree of freedom with the presence of prolate quadrupole deformations is also contemplated. (Author) [es

1948 AND THE COLD WAR IN MALAYA: SAMPLINGS OF MALAY REACTIONS

Directory of Open Access Journals (Sweden)

Abdul Rahman Haji Ismail

2009-01-01

Full Text Available This paper is a preliminary report of an on-going research on the reactions of the Malays in Malaya to the coming of the Cold War to the region, with particular reference to the importance of the year 1948. For the majority of the Malays, the Cold War was most popularly associated with the Emergency, which British authorities had declared in the effort to quell the armed uprising mounted by the MCP. The vast majority of Malays in Malaya were not interested in the on-going Cold War between the Western bloc led by the United States on the side the Eastern bloc led by the Soviet Union on the other. The preoccupations of the Malays during the immediate post-Pacific War period was nationalism and the concomitant effort to gain independence for Malaya from Britain. In particular, they had been rather anxious that the Malays, who were the native of the land, were not robbed of the custodianship over Malaya and political privileges of the Malays in independent Malaya. Consumed with these issues, the Malays had little interests in external affairs. It was perhaps the lack of Malay support that foredoomed the fate of communism in Malaya.

Dynamic response of thermal neutron measurements in electrochemically produced cold fusion subject to pulsed current

International Nuclear Information System (INIS)

Granada, Jose; Converti, Jose; Mayer, Roberto; Guido, German; Florido, Pablo; Patino, Nestor; Sobehart, Leonardo; Gomez, Silvia; Larreteguy, Axel

1988-01-01

The present work shows the results of measurements performed on electrolytic cells using a high efficiency (22%) neutron detection system in combination with a procedure involving a non-stationary current through the cell's circuit. Cold fusion was produced in electrolytic cells containing LiH dissolved in heavy water with a palladium cathode. The dynamic response to low frequency current pulses was measured. Characteristic patterns showing one or two bumps were obtained in a repeatable fashion. These patterns are strongly dependent on the previous charging history of the cathode. The technique employed seems to be very convenient as a research tool for a systematic study of the different variables governing the phenomenon. (Author)

Experimental investigation of the confinement of d(3He,p)α and d(d,p)t fusion reaction products in JET

DEFF Research Database (Denmark)

Bonheure, Georges; Hult, M.; Gonzalez de Orduna, R.

2012-01-01

In ITER, magnetic fusion will explore the burning plasma regime. Because such burning plasma is sustained by its own fusion reactions, alpha particles need to be confined (Hazeltine 2010 Fusion Eng. Des. 7–9 85). New experiments using d(3He,p)α and d(d,p)t fusion reaction products were performed...... in JET. Fusion product loss was measured from MHD-quiescent plasmas with a charged particle activation probe installed at a position opposite to the magnetic field ion gradient drift (see figure 1)—1.77 m above mid-plane—in the ceiling of JET tokamak. This new kind of escaping ion detector (Bonheure et...... al 2008 Fusion Sci. Technol. 53 806) provides for absolutely calibrated measurements. Both the mechanism and the magnitude of the loss are dealt with by this research. Careful analysis shows measured loss is in quantitative agreement with predictions from the classical orbit loss model. However...

Studies of heavy-ion reactions and transuranic nuclei

International Nuclear Information System (INIS)

Schroeder, W.U.

1993-08-01

This report contain papers on the following topics: The Cold-Fusion Saga; Decay Patterns of Dysprosium Nuclei Produced in 32 S + 118,124 Sn Fusion Reactions; Unexpected Features of Reactions Between Very Heavy Ions at Intermediate Bombarding Energies; Correlations Between Neutrons and Charged Products from the Dissipative Reaction 197 Au+ 208 Pb at E/A = 29 MeV; Dissipative Dynamics of Projectile-Like Fragment Production in the Reaction 209 Bi+ 136 Xe at E/A = 28.2 MeV; Dynamical Production of Intermediate-Mass Fragments in Peripheral 209 Bi+ 136 Xe Collisions at E lab /A = 28.2 MeV; The Rochester 960-Liter Neutron Multiplicity Meter; A Simple Pulse Processing Concept for a Low-Cost Pulse-Shape-Based Particle Identification; A One-Transistor Preamplifier for PMT Anode Signals; A Five-Channel Multistop TDC/Event Handler for the SuperBall Neutron Multiplicity Meter; Construction of the SuperBall -- a 16,000-Liter Neutron Detector for Calorimetric Studies of Intermediate-Energy Heavy-Ion Reactions; A Computer Code for Light Detection Efficiency Calculations for Photo-multipliers of a Neutron Detector; Evaluation of Gd-Loaded Liquid Scintillators for the SuperBall Neutron Calorimeter; and Measurement of the Interaction of Cosmic-Ray μ - with a Muon Telescope

Study of incomplete fusion reaction dynamics in 13C +165 Ho system and its dependence on various entrance channel parameters

Science.gov (United States)

Tali, Suhail A.; Kumar, Harish; Ansari, M. Afzal; Ali, Asif; Singh, D.; Ali, Rahbar; Giri, Pankaj K.; Linda, Sneha B.; Parashari, Siddharth; Kumar, R.; Singh, R. P.; Muralithar, S.

2018-02-01

The excitation functions for the evaporation residues populated in the interaction of 13C +165 Ho system have been measured at projectile energies ≈ 4-7 MeV/nucleon. Stacked foil activation technique followed by off-line γ-ray spectroscopy have been employed in the present work. The experimentally measured cross-sections are analyzed in the frame work of statistical model code PACE4, which takes into account only the complete fusion reaction cross-sections. The evaporation residues populated via xn and pxn channels were found to be in good agreement with the PACE4 predictions, while a significant enhancement in the measured cross-sections over PACE4 predictions is observed in case of α-emitting channels, which may be attributed to the incomplete fusion process. For the better understanding of incomplete fusion dynamics, the incomplete fusion fraction has also been deduced and its sensitivity with various entrance channel parameters like: projectile energy, mass-asymmetry, projectile structure in terms of Qα-value and Coulomb effect has been studied in the present work. The incomplete fusion fraction is found to increase with increasing the projectile energy and a strong projectile structure dependent mass-asymmetry systematic is also observed. The incomplete fusion fraction is also found to be small for more negative Qα-value projectile (13C) induced reactions as compared to less negative Qα-value projectiles (12C, 16O and 20Ne) induced reactions with the same target nucleus 165Ho. An interesting trend is obtained on further investigation of incomplete fusion dependence on Coulomb effect (ZPZT).

Neutron-induced reactions relevant for Inertial-Cofinement Fusion Experiments

Science.gov (United States)

Boswell, Melissa; Devlin, Mathew; Fotiadis, Nikolaos; Merrill, Frank; Nelson, Ronald; Tonchev, Anton

2014-09-01

The typical ignition experiment at the National Ignition Facility ablatively implodes a plastic capsule filled with DT fuel, generating a high flux of 14-MeV neutrons from the d(t,n) α reaction. There is some spread in the energy of these primary 14-MeV neutrons, which is mainly attributable to Doppler shifting from the relative thermal motion of the burning DT fuel. Neutrons created during this reaction have 5--10% chance of scattering before escaping the fuel assembly, losing some fraction of their energy in the scattering process. Neutrons emerging with an energy greater than the reaction energy are generated by a two-step process where neutrons first transfer momentum to a deuteron or tritium ion, these enhanced energy ions then fuse in flight to produce higher energy neutrons; some of these neutrons have energies in excess of 30 MeV. Measuring the fluencies of both the low- and high-energy neutrons is a powerful mechanism for studying the properties of the fuel assembly, and the various parameters important to inertial confinement fusion. We have developed a number of tools to measure the spectral characteristics of the NIF neutron spectrum. Most of these methods rely on exploiting the energy dependence of (n, γ), (n,2n), (n,3n) and (n,p) reactions on a variety o.

Effects of magnetization on fusion product trapping and secondary neutron spectra

International Nuclear Information System (INIS)

Knapp, P. F.; Schmit, P. F.; Hansen, S. B.; Gomez, M. R.; Hahn, K. D.; Sinars, D. B.; Peterson, K. J.; Slutz, S. A.; Sefkow, A. B.; Awe, T. J.; Harding, E.; Jennings, C. A.; Desjarlais, M. P.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Geissel, M.; Harvey-Thompson, A. J.; Porter, J. L.; Rochau, G. A.

2015-01-01

By magnetizing the fusion fuel in inertial confinement fusion (ICF) systems, the required stagnation pressure and density can be relaxed dramatically. This happens because the magnetic field insulates the hot fuel from the cold pusher and traps the charged fusion burn products. This trapping allows the burn products to deposit their energy in the fuel, facilitating plasma self-heating. Here, we report on a comprehensive theory of this trapping in a cylindrical DD plasma magnetized with a purely axial magnetic field. Using this theory, we are able to show that the secondary fusion reactions can be used to infer the magnetic field-radius product, BR, during fusion burn. This parameter, not ρR, is the primary confinement parameter in magnetized ICF. Using this method, we analyze data from recent Magnetized Liner Inertial Fusion experiments conducted on the Z machine at Sandia National Laboratories. We show that in these experiments BR ≈ 0.34(+0.14/−0.06) MG · cm, a ∼ 14× increase in BR from the initial value, and confirming that the DD-fusion tritons are magnetized at stagnation. This is the first experimental verification of charged burn product magnetization facilitated by compression of an initial seed magnetic flux

Fusion barrier distributions from capture and quasi-elastic excitation functions measured in reaction 36S, 48Ca, 64Ni+238U

International Nuclear Information System (INIS)

Kozulin, E. M.

2009-01-01

The subbarrier fusion enhancement in reactions with heavy ions were explained by taking into account coupling between relative motion and intrinsic degrees of freedom of interacting nuclei. The coupling of reaction channels manifests itself in the potential barrier between interacting nuclei giving rise to a distribution of fusion barrier instead of single barrier.Capture and quasi-elastic scattering excitation functions at backward angles were measured for 3 6S , 4 8C a, 6 4N i+2 38U reactions systems at energies close and below the Coulomb barrier (i.e. when the influence of the shell effects on the fusion and characteristics of the decay of the composite system is considerable). Representations of the barrier distributions were extracted from both capture and quasi-elastic data. The experimental representations of barrier distributions were compared with coupled-channel calculations using CCFULL code. The major part of these experiments has been performed at the U-400 accelerator of the Flerov Laboratory of Nuclear Reactions (JINR, Dubna); at the TANDEM-ALPI accelerator of the LNL (INFN, Legnaro, Italy) and at the Accelerator Laboratory of University of Jyvaeskylae (JYFL, Finland) using a time-of-flight spectrometer of fission fragments CORSET (CORrelation SET-up.) The extraction of the masses and Total Kinetic Energy (TKE) of the binary reaction products is based upon the analysis of the two-body velocity In the case of the fusion-fission and quasi-fission processes, the observed peculiarities of mass and energy distributions of the fragments, the ratio between the fusion-fission and quasi-fission cross sections are determined deformations of interaction nuclei and angular momentum carried in the di-nuclear system and the shell structure of the formed fragments. In this work, the high-precision capture and quasi-elastic scattering excitation function data are presented.The influence of projectile and target excitations and nucleon transfer on fusion barrier

Thermonuclear fusion

International Nuclear Information System (INIS)

Weisse, J.

2000-01-01

This document takes stock of the two ways of thermonuclear fusion research explored today: magnetic confinement fusion and inertial confinement fusion. The basic physical principles are recalled first: fundamental nuclear reactions, high temperatures, elementary properties of plasmas, ignition criterion, magnetic confinement (charged particle in a uniform magnetic field, confinement and Tokamak principle, heating of magnetized plasmas (ohmic, neutral particles, high frequency waves, other heating means), results obtained so far (scale laws and extrapolation of performances, tritium experiments, ITER project), inertial fusion (hot spot ignition, instabilities, results (Centurion-Halite program, laser experiments). The second part presents the fusion reactor and its associated technologies: principle (tritium production, heat source, neutron protection, tritium generation, materials), magnetic fusion (superconducting magnets, divertor (role, principle, realization), inertial fusion (energy vector, laser adaptation, particle beams, reaction chamber, stresses, chamber concepts (dry and wet walls, liquid walls), targets (fabrication, injection and pointing)). The third chapter concerns the socio-economic aspects of thermonuclear fusion: safety (normal operation and accidents, wastes), costs (costs structure and elementary comparison, ecological impact and external costs). (J.S.)

Energy related applications of elementary particle physics

International Nuclear Information System (INIS)

Rafelski, J.

1989-01-01

Study of muon catalysis of nuclear fusion and phenomena commonly referred to as cold fusion has been central to our effort. Muon catalyzed fusion research concentrated primarily on the identification of energy efficient production of muons, and the understanding and control of the density dependence of auto-poisoning (sticking) of the catalyst. We have also developed the in-flight fusion description of the tμ-d reaction, and work in progress shows promise in explaining the fusion cycle anomalies and smallness of sticking as a consequence of the dominant role of such reactions. Our cold fusion work involved the exploration of numerous environments for cold fusion reactions in materials used in the heavy water electrolysis, with emphasis on reactions consistent with the conventional knowledge of nuclear physics reactions. We then considered the possibility that a previously unobserved ultra-heavy particle X - is a catalyst of dd fusion, explaining the low intensity neutrons observed by Jones et. al. 29 refs

Muon-catalyzed fusion: A new direction in fusion research

International Nuclear Information System (INIS)

Jones, S.E.

1986-01-01

In four years of intensive research, muon-catalyzed fusion has been raised from the level of a scientific curiosity to a potential means of achieving clean fusion energy. This novel approach to fusion is based on the fact that a sub-atomic particle known as a ''muon'' can induce numerous energy-releasing fusion reactions without the need for high temperatures or plasmas. Thus, the muon serves as a catalyst to facilitate production for fusion energy. The success of the research effort stems from the recent discovery of resonances in the reaction cycle which make the muon-induced fusion process extremely efficient. Prior estimates were pessimistic in that only one fusion per muon was expected. In that case energy balance would be impossible since energy must be invested to generate the muons. However, recent work has gone approximately half-way to energy balance and further improvements are being worked on. There has been little time to assess the full implications of these discoveries. However, various ways to use muon-catalyzed fusion for electrical power production are now being explored

Muon-catalyzed fusion: a new direction in fusion research

International Nuclear Information System (INIS)

Jones, S.E.

1986-01-01

In four years of intensive research, muon-catalyzed fusion has been raised from the level of a scientific curiosity to a potential means of achieving clean fusion energy. This novel approach to fusion is based on the fact that a sub-atomic particle known as a ''muon'' can induce numerous energy-releasing fusion reactions without the need for high temperatures or plasmas. Thus, the muon serves as a catalyst to facilitate production for fusion energy. The success of the research effort stems from the recent discovery of resonances in the reaction cycle which make the muon-induced fusion process extremely efficient. Prior estimates were pessimistic in that only one fusion per muon was expected. In that case energy balance would be impossible since energy must be invested to generate the muons. However, recent work has gone approximately half-way to energy balance and further improvements are being worked on. There has been little time to assess the full implications of these discoveries. However, various ways to use muon-catalyzed fusion for electrical power production are now being explored

Estimates of fission barrier heights for neutron-deficient Po to Ra nuclei produced in fusion reactions

Directory of Open Access Journals (Sweden)

Sagaidak Roman

2017-01-01

Full Text Available The cross section data for fission and evaporation residue production in fusion reactions leading to nuclei from Po to Ra have been considered in a systematic way in the framework of the conventional barrier-passing (fusion model coupled with the statistical model. The cross section data obtained in very asymmetric projectile-target combinations can be described within these models rather well with the adjusted model parameters. In particular, one can scale and fix the macroscopic (liquid-drop fission barrier heights (FBHs for nuclei involved in the de-excitation of compound nuclei produced in the reactions. The macroscopic FBHs for nuclei from Po to Ra have been derived in the framework of such analysis and compared with the predictions of various theoretical models.

Complete fusion excitation function for the 16O + natS reaction

International Nuclear Information System (INIS)

Wang Sufang; Zheng Jiwen; Liu Guoxing

1994-01-01

The complete fusion excitation function for the 16 O + nat S reaction has been measured in the range of 50-75 MeV with a step of 1.0 MeV by using a position sensitive ΔE-E telescope system. The model parameters have been extracted from data analysis. The striking gross structure of the excitation function has been observed. The energies of peaks are at E CM 38,43 and 48 MeV respectively

Nuclear X-ray emission after fusion of heavy ions

Energy Technology Data Exchange (ETDEWEB)

Berner, Christian; Muecher, Dennis; Gernhaeuser, Roman; Faestermann, Thomas [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); Henning, Walter [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); Argonne National Laboratory (United States); Morita, Kosuke; Morimoto, Kouji; Kaji, Daija [RIKEN, Research Group for Superheavy Elements (Japan)

2015-07-01

The goal is to establish in-beam K-X-ray spectroscopy as a sensitive tool to identify super heavy elements (SHEs) produced in fusion reactions via their proton number. SHEs, formed after cold or hot fusion, are usually identified via the alpha-decay products, which have to be connected to well-known elements. In case of hot fusion, the daughter nuclei quickly undergo spontaneous fission, so that the identification of the produced SHEs is difficult. Using the hot fusion approach in our first test experiments, the resultant products will be analysed by the gas-filled GARIS separator at the RILAC facility at RIKEN. As the X-ray detector is required to have superior energy and timing resolution to best identify the rare events at highest masses and to supress random coincidences as sufficient as possible, we chose a thin and planar geometry, which also reduces the damage caused by fast neutrons. We show first measurements using the MINIBALL Ge array at Munich. Additionally we report on our feasibility studies and on first tests using the new detector at high count rates together with a powerful DAQ system and transistor reset preamplifiers.

Fusion evaporation residues and the distribution of reaction strength in 16O + 40Ca and 28Si + 28Si reactions

International Nuclear Information System (INIS)

Kolata, J.J.; Hinnefeld, J.; Kovar, D.G.

1985-01-01

In measurements performed previously at ANL, studying the two entrance channels 16 O + 40 Ca and 28 Si + 28 Si which form the same compound nucleus 56 Ni, it was found that at higher bombarding energies (E/sub Lab/ > 5-7 MeV/nucleon) the distributions of reaction strength was dramatically different. Although the total reaction cross section behaviors for the two entrance channels are similar, the total evaporation residue (ER) cross sections for 28 Si + 28 Si decrease rapidly with increasing bombarding energies and up to the highest energy studied show no evidence for incomplete fusion processes. For 16 O + 40 Ca the ER cross section remains constant at approximately 1 barn with increasing bombarding energy and shows evidence of increasing contributions from incomplete fusion. To better understand this apparent dependence on the mass asymmetry in the entrance channel, coincidence measurements between evaporation residue-like products and heavy ions on the opposite side of the beam were performed for the two systems at E/sub Lab/ = 8 MeV/nucleon

Molecular resonances, fusion reactions and surface transparency of interaction between heavy ions

International Nuclear Information System (INIS)

Abe, Yasuhisa.

1980-01-01

A review of the Band Crossing Model is given, including recent results on the 16 O + 16 O system. Surface Transparency is discussed in the light of the recent development in our understanding of the fusion reaction mechanisms and by calculating the number of open channels available to direct reactions. The existence of the Molecular Resonance Region is suggested in several systems by the fact that Band Crossing Region overlaps with the Transparent Region. A systematic study predicts molecular resonances in the 14 C + 14 C and 12 C + 14 C systems as prominent as those observed in the 16 O + 16 O and 12 C + 16 O systems

Kinetics of Cold-Cap Reactions for Vitrification of Nuclear Waste Glass Based on Simultaneous Differential Scanning Calorimetry - Thermogravimetry (DSC-TGA) and Evolved Gas Analysis (EGA)

Energy Technology Data Exchange (ETDEWEB)

Rodriguez, Carmen P.; Pierce, David A.; Schweiger, Michael J.; Kruger, Albert A.; Chun, Jaehun; Hrma, Pavel R.

2013-12-03

For vitrifying nuclear waste glass, the feed, a mixture of waste with glass-forming and modifying additives, is charged onto the cold cap that covers 90-100% of the melt surface. The cold cap consists of a layer of reacting molten glass floating on the surface of the melt in an all-electric, continuous glass melter. As the feed moves through the cold cap, it undergoes chemical reactions and phase transitions through which it is converted to molten glass that moves from the cold cap into the melt pool. The process involves a series of reactions that generate multiple gases and subsequent mass loss and foaming significantly influence the mass and heat transfers. The rate of glass melting, which is greatly influenced by mass and heat transfers, affects the vitrification process and the efficiency of the immobilization of nuclear waste. We studied the cold-cap reactions of a representative waste glass feed using both the simultaneous differential scanning calorimetry thermogravimetry (DSC-TGA) and the thermogravimetry coupled with gas chromatography-mass spectrometer (TGA-GC-MS) as complementary tools to perform evolved gas analysis (EGA). Analyses from DSC-TGA and EGA on the cold-cap reactions provide a key element for the development of an advanced cold-cap model. It also helps to formulate melter feeds for higher production rate.

On the implementation of a chain nuclear reaction of thermonuclear fusion on the basis of the p+11B process

Science.gov (United States)

Belyaev, V. S.; Krainov, V. P.; Zagreev, B. V.; Matafonov, A. P.

2015-07-01

Various theoretical and experimental schemes for implementing a thermonuclear reactor on the basis of the p+11B reaction are considered. They include beam collisions, fusion in degenerate plasmas, ignition upon plasma acceleration by ponderomotive forces, and the irradiation of a solid-state target from 11B with a proton beam under conditions of a Coulomb explosion of hydrogen microdrops. The possibility of employing ultra-short high-intensity laser pulses to initiate the p+11B reaction under conditions far from thermodynamic equilibrium is discussed. This and some other weakly radioactive thermonuclear reactions are promising owing to their ecological cleanness—there are virtually no neutrons among fusion products. Nuclear reactions that follow the p+11B reaction may generate high-energy protons, sustaining a chain reaction, and this is an advantage of the p+11B option. The approach used also makes it possible to study nuclear reactions under conditions close to those in the early Universe or in the interior of stars.

Neutrons and fusion

International Nuclear Information System (INIS)

Maynard, C.W.

1976-01-01

The production of energy from fusion reactions does not require neutrons in the fundamental sense that they are required in a fission reactor. Nevertheless, the dominant fusion reaction, that between deuterium and tritium, yields a 14 MeV neutron. To contrast a fusion reactor based on this reaction with the fission case, 3 x 10 20 such neutrons produced per gigawatt of power. This is four times as many neutrons as in an equivalent fission reactor and they carry seven times the energy of the fission neutrons. Thus, they dominate the energy recovery problem and create technological problems comparable to the original plasma confinement problem as far as a practical power producing device is concerned. Further contrasts of the fusion and fission cases are presented to establish the general role of neutrons in fusion devices. Details of the energy deposition processes are discussed and those reactions necessary for producing additional tritium are outlined. The relatively high energy flux with its large intensity will activate almost any materials of which the reactor may be composed. This activation is examined from the point of view of decay heat, radiological safety, and long-term storage. In addition, a discussion of the deleterious effects of neutron interactions on materials is given in some detail; this includes the helium and hydrogen producing reactions and displacement rate of the lattice atoms. The various materials that have been proposed for structural purposes, for breeding, reflecting, and moderating neutrons, and for radiation shielding are reviewed from the nuclear standpoint. The specific reactions of interest are taken up for various materials and finally a report is given on the status and prospects of data for fusion studies

Numerical simulation by a random particle method of Deuterium-Tritium fusion reactions in a plasma*

Directory of Open Access Journals (Sweden)

Charles Fréderique

2013-01-01

Full Text Available We propose and we justify a Monte-Carlo algorithm which solves a spatially homogeneous kinetic equation of Boltzmann type that models the fusion reaction between a deuterium ion and a tritium ion, and giving an α particle and a neutron. The proposed algorithm is validated with the use of explicit solutions of the kinetic model obtained by replacing the fusion cross-section by a Maxwellian cross section. On propose et on justifie un algorithme de type Monte-Carlo permettant de résoudre un modèle cinétique homogène en espace de type Boltzmann modélisant la réaction de fusion entre un ion deutérium et un ion tritium, et donnant une particule α et un neutron. L’algorithme proposé est par ailleurs validé via des solutions explicites du modèle cinétique obtenues en remplaçant la section efficace de fusion par une section efficace maxwellienne.

Coupled-channel calculation for cross section of fusion and barrier distribution of {}^{16,17,18}O + {}^{16}O reactions

Science.gov (United States)

Fereidonnejad, R.; Sadeghi, H.; Ghambari, M.

2018-03-01

In this work, the effect of multi-phonon excitation on heavy-ion fusion reactions has been studied and fusion barrier distributions of energy intervals near and below the Coulomb barrier have been studied for 16,17,18O + 16O reactions. The structure and deformation of nuclear projectiles have been studied. Given the adaptation of computations to experimental data, our calculations predict the behavior of reactions in intervals of energy in which experimental measurements are not available. In addition the S-factor for these reactions has been calculated. The results showed that the structure and deformation of a nuclear projectile are important factors. The S-factor, obtained in the coupled-channel calculations for the {}^{16}O + {}^{16}O, {}^{17}O +{}^{16}O and {}^{18}O +{}^{16}O reactions, showed good agreement with the experimental data and had a maximum value at an energy near 5, 4.5 and 4 MeV, respectively.

The cross sections of fusion-evaporation reactions: the most promising route to superheavy elements beyond Z=118

Directory of Open Access Journals (Sweden)

Jadambaa Khuyagbaatar

2017-01-01

Full Text Available The synthesis of superheavy elements beyond oganesson (Og, which has atomic number Z = 118, is currently one of the main topics in nuclear physics. An absence of sufficient amounts of target material with atomic numbers heavier than californium (Z = 98 forces the use of projectiles heavier than 48Ca (Z = 20, which has been successfully used for the discoveries of elements with Z = 114 - 118 in complete fusion reactions. Experimental cross sections of 48Ca with actinide targets behave very differently to “cold” and “hot” fusion-evaporation reactions, where doubly-magic lead and deformed actinides are used as targets, respectively. The known cross sections of these reactions have been analysed compared to calculated fission barriers. It has been suggested that observed discrepancies between the cross sections of 48Ca-induced and other fusionevaporation reactions originate from the shell structure of the compound nucleus, which lies in the island of the stability. Besides scarcely known data on other reactions involving heavier projectiles, the most promising projectile for the synthesis of the elements beyond Og seems to be 50Ti. However, detailed studies of 50Ti, 54Cr, 58Fe and 64Ni-induced reactions are necessary to be performed in order to fully understand the complexities of superheavy element formation.

Atomic fusion, Gerrard atomic fusion

International Nuclear Information System (INIS)

Gerrard, T.H.

1980-01-01

In the approach to atomic fusion described here the heat produced in a fusion reaction, which is induced in a chamber by the interaction of laser beams and U.H.F. electromagnetic beams with atom streams, is transferred to a heat exchanger for electricity generation by a coolant flowing through a jacket surrounding the chamber. (U.K.)

Examination of a proposed phonon-coupling mechanism for cold fusion

International Nuclear Information System (INIS)

Crawford, O.H.

1992-01-01

In this paper the proposed nuclear energy in an atomic lattice (NEAL) mechanism for nuclear fusion in a cathode during electrolysis of D 2 O is examined. In this mechanism, coupled harmonic motion of deuterons is supposed to lead to a reduction in the width of the Coulomb barrier for proton-deuteron (p-d) fusion in palladium, thereby substantially increasing the fusion rate. Instead, it is argued that deuteron-deuteron coupling does not have an important effect and that interaction with phonons does not enhance the p-d fusion rate

Nuclear dynamics in heavy ion induced fusion-fission reactions

International Nuclear Information System (INIS)

Kapoor, S.S.

1992-01-01

Heavy ion induced fission and fission-like reactions evolve through a complex nuclear dynamics encountered in the medium energy nucleus-nucleus collisions. In the recent years, measurements of the fragment-neutron and fragment-charged particle angular correlations in heavy ion induced fusion-fission reactions, have provided new information on the dynamical times of nuclear deformations of the initial dinuclear complex to the fission saddle point and the scission point. From the studies of fragment angular distributions in heavy ion induced fission it has been possible to infer the relaxation times of the dinuclear complex in the K-degree of freedom and our recent measurements on the entrance channel dependence of fragment anisotropies have provided an experimental signature of the presence of fissions before K-equilibration. This paper reviews recent experimental and theoretical status of the above studies with particular regard to the questions relating to dynamical times, nuclear dissipation and the effect of nuclear dissipation on the K-distributions at the fission saddle in completely equilibrated compound nucleus. (author). 19 refs., 9 figs

Massachusetts Institute of Technology Plasma Fusion Center, 1988--1989 report to the President

International Nuclear Information System (INIS)

1989-07-01

This report discusses the following topics on fusion energy: cold fusion; alcator confinement experiments; applied plasma physics research; fusion systems; coherent electromagnetic wave generation; and fusion technology and engineering

Some fusion perspectives

International Nuclear Information System (INIS)

McNally, J.R. Jr.

1977-01-01

Some of the concepts of nuclear fusion reactions, advanced fusion fuels, environmental impacts, etc., are explored using the following general outline: I. Principles of Fusion (Nuclear Fuels and Reactions, Lawson Condition, n tau vs T, Nuclear Burn Characteristics); II. Magnetic Mirror Possibilities (the Ion Layer and Electron Layer, Exponential Build-up at MeV energies, Lorentz trapping at GeV energies); III. Pellet Fuel Fusion Prospects (Advanced Pellet Fuel Fusion Prospects, Burn Characteristics and Applications, Excitation-heating Prospects for Runaway Ion Temperatures). Inasmuch as the outline is very skeletal, a significant research and development effort may be in order to evaluate these prospects in more detail and hopefully ''harness the H-bomb'' for peaceful applications, the author concludes. 28 references

Extricate of incomplete fusion reactions at 4-7 MeV/A System:19F+159Tb

International Nuclear Information System (INIS)

Unnati; Mandal, S.K.; Yadav, A.; Singh, D.P.; Goswami, S.; Singh, B.P.; Sharma, M.K.

2015-01-01

Probing of heavy ion interactions and extricating of incomplete fusion (ICF) reactions at low energy regime is a topic of current interest. The main points of such studies is to explore the effect of various entrance channel parameters, viz., (i) the projectile energy, (ii) the mass asymmetry of interacting partners, and (iii) the input angular momenta imparted into the system. It is also pointed out that a separation of CF (Complete Fusion) from ICF is important for meaningful interpretation towards the splitting of nuclei. Further, considerable efforts are being employed to synthesize super heavy nuclei, the presence of various competing channels may add complexity to the synthesis of super heavy nuclei and obstruct the formation of such nuclei. Although, it is now possible to investigate reaction mechanism involved in formation of such nuclei but experimental studies are limited

Influence of the entrance channel in the fusion reaction 318 MeV 74Ge+74Ge

International Nuclear Information System (INIS)

Zhu, L.H.; Cinausero, M.; Angelis, G. de; De Poli, M.; Fioretto, E.; Gadea, A.; Napoli, D.R.; Prete, G.; Lucarelli, F.

1998-01-01

Entrance channel effects in the fusion of heavy ions have been studied by using the 74 Ge+ 74 Ge reaction at 318 MeV. The population of the yrast superdeformed band in 144 Gd shows an increase when compared with the results obtained in the more asymmetric 48 Ti+ 100 Mo reaction at 215 MeV. The relative yields of the different evaporation residues produced in the 74 Ge+ 74 Ge and in the 48 Ti+ 100 Mo reactions are very similar, with the exception of the 145,144 Gd residual nuclei (3n and 4n decay channels) which are populated with a larger yield in the symmetric reaction. Statistical model calculations reproduce qualitatively such effect if a fission delay is explicitly taken into account. Effects related to fusion barrier fluctuations seem to be important in determining the spin distributions of the compound nucleus. The spectra of the high energy γ-rays emitted in the 74 Ge+ 74 Ge reaction have been measured as a function of the γ-ray multiplicity as well as in coincidence with selected evaporation residues. They are reproduced by standard statistical model calculations with GDR parameters taken from systematics, demonstrating that, in agreement with dynamical model prediction, the emission of γ-rays from the dinucleus formed in the earlier stage of the collision is unimportant. (orig.)

Application of the water gas shift reaction to fusion fuel exhaust streams

International Nuclear Information System (INIS)

McKay, A.M.; Cheh, C.H.; Glass, R.W.

1983-10-01

In a Fusion Fuel Clean Up (FCU) system, impurities will be removed from the fusion reactor exhaust and neutral beam line streams. Tritium in this impurity stream will be recovered and recycled to the fuel stream. In one flowsheet configuration of the Tritium Systems Test Assembly (TSTA), tritium is recovered from a simulated impurity stream via uranium hot metal beds and recycled to an isotope separation system. This study has shown, however, that the catalyzed water gas shift reaction, by which (H,D,T) 2 O and CO are converted to (H,D,T) 2 and CO 2 is a better method of (H,D,T) 2 O reduction than the hot metal beds. Catalytic reactors were designed, built and tested to provide data for the design of a prototype reactor to replace the hot metal beds in the FCU system. The prototype reactor contains only 10 g of catalyst and is expected to last at least 5 years. The reactor is small (1.3 cm OD x 13 cm long), operates at low temperatures (approximately 490 K) and will convert water to hydrogen, at a CO/H 2 O ratio of 1.5, with an efficiency of greater than 98 percent. Results show that the catalytic reactor is very stable even during upset conditions. Wide ranges of flow and a CO/H 2 O ratio variance from 1.3 upward have little effect on the conversion efficiency. Short term high temperature excursions do not affect the catalyst and lower temperatures will simply decrease the reaction rate resulting in lower conversions. The reactor appears to be unaffected by NO 2 , CO 2 , O 2 and N 2 in the feed stream at concentration levels expected in a fusion reactor exhaust stream

Knudsen and inverse Knudsen layer effect on tail ion distribution and fusion reactivity in inertial confinement fusion targets

Science.gov (United States)

McDevitt, C. J.; Tang, X.-Z.; Guo, Z.; Berk, H. L.

2014-10-01

A series of reduced models are used to study the fast ion tail in the vicinity of a transition layer between plasmas at disparate temperatures and densities, which is typical of the gas-pusher interface in inertial confinement fusion targets. Emphasis is placed on utilizing progressively more comprehensive models in order to identify the essential physics for computing the fast ion tail at energies comparable to the Gamow peak. The resulting fast ion tail distribution is subsequently used to compute the fusion reactivity as a function of collisionality and temperature. It is found that while the fast ion distribution can be significantly depleted in the hot spot, leading to a reduction of the fusion reactivity in this region, a surplus of fast ions is present in the neighboring cold region. The presence of this fast ion surplus in the neighboring cold region is shown to lead to a partial recovery of the fusion yield lost in the hot spot.

Astrophysical Nuclear Reaction Rates in the Dense Metallic Environments

Science.gov (United States)

Kilic, Ali Ihsan

2017-09-01

Nuclear reaction rates can be enhanced by many orders of magnitude in dense and relatively cold astrophysical plasmas such as in white dwarfs, brown dwarfs, and giant planets. Similar conditions are also present in supernova explosions where the ignition conditions are vital for cosmological models. White dwarfs are compact objects that have both extremely high interior densities and very strong local magnetic fields. For the first time, a new formula has been developed to explain cross section and reaction rate quantities for light elements that includes not only the nuclear component but also the material dependence, magnetic field, and crystal structure dependency in dense metallic environments. I will present the impact of the developed formula on the cross section and reaction rates for light elements. This could have possible technological applications in energy production using nuclear fusion reactions.

Pinch me - I'm fusing. Fusion Power - what is it? What is a z pinch? And why are z-pinches a promising fusion power technology?

International Nuclear Information System (INIS)

DERZON, MARK S.

2000-01-01

The process of combining nuclei (the protons and neutrons inside an atomic nucleus) together with a release of kinetic energy is called fusion. This process powers the Sun, it contributes to the world stockpile of weapons of mass destruction and may one day generate safe, clean electrical power. Understanding the intricacies of fusion power, promised for 50 years, is sometimes difficult because there are a number of ways of doing it. There is hot fusion, cold fusion and con-fusion. Hot fusion is what powers suns through the conversion of mass energy to kinetic energy. Cold fusion generates con-fusion and nobody really knows what it is. Even so, no one is generating electrical power for you and me with either method. In this article the author points out some basic features of the mainstream approaches taken to hot fusion power, as well as describe why z pinches are worth pursuing as a driver for a power reactor and how it may one day generate electrical power for mankind

Physics of laser-plasma interaction for shock ignition of fusion reactions

International Nuclear Information System (INIS)

Tikhonchuk, V T; Colaïtis, A; Vallet, A; Llor Aisa, E; Duchateau, G; Nicolaï, Ph; Ribeyre, X

2016-01-01

The shock ignition scheme is an alternative approach, which aims to achieve ignition of fusion reactions in two subsequent steps: first, the target is compressed at a low implosion velocity and second, a strong converging shock is launched during the stagnation phase and ignites the hot spot. In this paper we describe the major elements of this scheme and recent achievements concerning the laser-plasma interaction, the crucial role of hot electrons in the shock generation, the shock amplification in the imploding shell and the ignition conditions. (paper)

Origin of a maximum of the astrophysical S factor in heavy-ion fusion reactions at deep subbarrier energies

Science.gov (United States)

Hagino, K.; Balantekin, A. B.; Lwin, N. W.; Thein, Ei Shwe Zin

2018-03-01

The hindrance phenomenon of heavy-ion fusion cross sections at deep subbarrier energies often accompanies a maximum of an astrophysical S factor at a threshold energy for fusion hindrance. We argue that this phenomenon can naturally be explained when the fusion excitation function is fitted with two potentials, with a larger (smaller) logarithmic slope at energies lower (higher) than the threshold energy. This analysis clearly suggests that the astrophysical S factor provides a convenient tool to analyze the deep subbarrier hindrance phenomenon, even though the S factor may have a strong energy dependence for heavy-ion systems unlike that for astrophysical reactions.

Heat and cold accumulators in vehicles

Energy Technology Data Exchange (ETDEWEB)

Kauranen, P.; Wikstroem, L. (VTT Technical Research Centre of Finland, Advanced Materials, Tampere (Finland)); Heikkinen, J. (VTT Technical Research Centre of Finland, Building Services and Indoor Environment, Espoo (Finland)); Laurikko, J.; Elonen, T. (VTT Technical Research Centre of Finland, Emission Control, Espoo (Finland)); Seppaelae, A. (Helsinki Univ. of Technology, Applied Thermodynamics, Espoo (Finland)). Email: ari.seppala@tkk.fi

2009-07-01

Phase Change Material (PCM) based heat and cold accumulators have been tailored for transport applications including a mail delivery van as well as the cold chains of foodstuff and blood products. The PCMs can store relative large amount of thermal energy in a narrow temperature interval as latent heat of fusion of their melting and crystallization processes. Compact heat and cold accumulators can be designed using PCMs. The aim of the project has been to reduce the exhaust gas and noise emissions and improve the fuel economy of the transport systems and to improve the reliability of the cold chains studied by storing thermal energy in PCM accumulators. (orig.)

Dynamics of the fusion reaction in the dtμ- system

International Nuclear Information System (INIS)

Belyaev, V.B.; Revai, J.; Zubarev, A.L.

1988-08-01

A dynamical scheme based on the (td,αn) two-channel model is derived for the description of the fusion reaction in the dtμ - system. Special attention is paid to the correct specification of the final states. Several possibilities are pointed out for the systematic improvement of the sudden approximation for the sticking coefficient. It seems to be useful to outline a general formulation of these processes which would allow a clear comparison of existing approaches. The lack of satisfactory agreement between experimental and theoretical values of the sticking coefficient is a further argument in favour of the programme. (R.P.) 10 refs

Dynamical limitations to heavy-ion fusion

International Nuclear Information System (INIS)

Back, B.B.

1983-01-01

In spite of the many attempts to synthesize superheavy elements in recent years, these efforts have not yet been successful. Recent improved theoretical models of heavy-ion fusion reactions suggest that the formation of super-heavy elements is hindered by the dynamics of the process. Several recent experiments lend support to these theories. The necessity of an excess radial velocity (extra push) over the Coulomb barrier in order to induce fusion is observed experimentally as predicted by the theory. So is a new reaction mechanism, called quasi-fission which tend to exhaust the part of the reaction cross section, which would otherwise lead to fusion. The present study shows that the angular distribution of fragments from quasi-fission processes are very sensitive to the occurrence of this reaction mechanism. A slight modification of one parameter in the theory demanded by the observation of quasi-fission for lighter projectiles via the angular distributions, has the consequence of posing even more-stringent limitations on heavy-ion-fusion reactions. This reduces even further the possibility for synthesizing and identifying superheavy elements in heavy-ion-fusion reactions

Fusion reactor wastes

International Nuclear Information System (INIS)

Young, J.R.

1976-01-01

The fusion reactor currently is being developed as a clean source of electricity with an essentially infinite source of fuel. These reactors are visualized as using a fusion reaction to generate large quantities of high temperature energy which can be used as process heat or for the generation of electricity. The energy would be created primarily as the kinetic energy of neutrons or other reaction products. Neutron energy could be converted to high-temperature heat by moderation and capture of the neutrons. The energy of other reaction products could be converted to high-temperature heat by capture, or directly to electricity by direct conversion electrostatic equipment. An analysis to determine the wastes released as a result of operation of fusion power plants is presented

Cross-sections and average angular momenta in fusion reactions near the coulomb barrier

International Nuclear Information System (INIS)

Dasgupta, M.

1992-01-01

In recent years there has been an increasing interest in the study of heavy ion collisions near the Coulomb barrier. This has been triggered mainly by the observations of enhancements by factors of about one to two order of magnitude in sub-Coulomb barrier fusion (SBF) cross-sections between medium mass nuclei, as compared to predictions based on one-dimensional barrier penetration model (l-d BPM). Though, a considerable amount of work both theoretical and experimental has been done in this field, a complete understanding of the SBF phenomenon has not yet been achieved. The relation between fusion excitation function and angular momentum (l) distribution in SBF reactions is a topic of current interest. It is believed that l-distributions provide a more stringent test of SBF models that the excitation functions alone. Simultaneous measurement of l-distribution (or its moments) and fusion excitation function is expected to lead to a better understanding of the relationship between these two qualities. Such information has been obtained in experiments done at pelletron accelerator facility. In the present talk the measurement of fusion cross-sections and the method of determination of average l from partial evaporation residue cross-section has been elaborated. An analysis of the experimental data on the basis of some of the SBF models has been discussed briefly. (author). 13 refs

Towards fusion power

International Nuclear Information System (INIS)

Venkataraman, G.

1975-01-01

An attempt has been made to present general but broad review of the recent developments in the field of plasma physics and its application to fusion power. The first chapter describes the fusion reactions and fusion power systems. The second chapter deals in detail with production and behaviour of plasma, screening, oscillations, instability, energy losses, temperature effects, etc. Magnetic confinements, including pinch systems, toroidal systems such as Tokamac and stellarator, minor machine, etc. are discussed in detail in chapter III. Laser produced plasma, laser implosion and problems associated with it and future prospects are explained in chapter IV. Chapter V is devoted entirely to the various aspects of hybrid systems. The last chapter throws light on problems of fusion technology, such as plasma heating, vacuum requirements, radiation damage, choice of materials, blanket problems, hazards of fusion reactions, etc. (K.B.)

Process and apparatus for producing nuclear fusion reactions

International Nuclear Information System (INIS)

Maglich, B.C.; Nering, J.E.; Mazarakis, M.G.; Miller, R.A.

1976-01-01

A process is submitted for the production of fusion reactions between particles of like polarity. This process consists essentially in delimitating a pumped down space comprising a central axis and a central plane arranged radially, and perpendicular to this central axis, in developing in this space a magnetic field the intensity of which decreases when the radial distance increases from the central axis and of which the intensity increases from the central plane, along this central axis. Particles of the same polarity are produced according to a population distribution in which the density of the particles in the greatest vibrational state exceeds the density of the particles in the greatest vibrational state in a normal distribution. These particles are injected near the centre of the magnetic field, by radial injection towards the inside as from the periphery of the space, in the same plane as the central plane [fr

Resonances and fusion in heavy ion reactions: new models and developments

International Nuclear Information System (INIS)

Cindro, N.

1982-01-01

Several aspects of the problem of the resonant behaviour of heavy-ion induced reactions are discussed. First, the problem is set in its relation to fundamental nuclear physics and our understanding of nuclear structure. It is suggested that, if the resonant behaviour of heavy-ion reactions is indeed due to the presence of particular configurations in the composite systems, these configurations must have a very specific nature which prevents their mixing with the adjacent states or else other conditons (e.g. low level density) should be met. Further on, the problem of resonant behaviour observed in back-angle elastic scattering and in forward-angle reaction data is discussed. Collisions between heavy ions leading to the composite systems 36 Ar and 40 Ca are used to discuss the apparent lack of correlation between these two sets of data. A way to understand it, based on the fragmentation of broad resonances, is suggested. In the third part the relation between structure in the fusion cross section excitation functions and that in reaction channel cross sections is discussed. Finally, in the fourth part, the orbiting-cluster model of heavy-ion resonances is briefly described and its predictions discussed. Based on this model a list is given of colliding heavy-ion systems where resonances are expected. (author)

Nuclear fusion

International Nuclear Information System (INIS)

Al-zaelic, M.M.

2013-01-01

Nuclear fusion can be relied on to solve the global energy crisis if the process of limiting the heat produced by the fusion reaction (Plasma) is successful. Currently scientists are progressively working on this aspect whereas there are two methods to limit the heat produced by fusion reaction, the two methods are auto-restriction using laser beam and magnetic restriction through the use of magnetic fields and research is carried out to improve these two methods. It is expected that at the end of this century the nuclear fusion energy will play a vital role in overcoming the global energy crisis and for these reasons, acquiring energy through the use of nuclear fusion reactors is one of the most urge nt demands of all mankind at this time. The conclusion given is that the source of fuel for energy production is readily available and inexpensive ( hydrogen atoms) and whole process is free of risks and hazards, especially to general health and the environment . Nuclear fusion importance lies in the fact that energy produced by the process is estimated to be about four to five times the energy produced by nuclear fission. (author)

Sub-barrier quasifission in heavy element formation reactions with deformed actinide target nuclei

Science.gov (United States)

Hinde, D. J.; Jeung, D. Y.; Prasad, E.; Wakhle, A.; Dasgupta, M.; Evers, M.; Luong, D. H.; du Rietz, R.; Simenel, C.; Simpson, E. C.; Williams, E.

2018-02-01

Background: The formation of superheavy elements (SHEs) by fusion of two massive nuclei is severely inhibited by the competing quasifission process. Low excitation energies favor SHE survival against fusion-fission competition. In "cold" fusion with spherical target nuclei near 208Pb, SHE yields are largest at beam energies significantly below the average capture barrier. In "hot" fusion with statically deformed actinide nuclei, this is not the case. Here the elongated deformation-aligned configurations in sub-barrier capture reactions inhibits fusion (formation of a compact compound nucleus), instead favoring rapid reseparation through quasifission. Purpose: To determine the probabilities of fast and slow quasifission in reactions with prolate statically deformed actinide nuclei, through measurement and quantitative analysis of the dependence of quasifission characteristics at beam energies spanning the average capture barrier energy. Methods: The Australian National University Heavy Ion Accelerator Facility and CUBE fission spectrometer have been used to measure fission and quasifission mass and angle distributions for reactions with projectiles from C to S, bombarding Th and U target nuclei. Results: Mass-asymmetric quasifission occurring on a fast time scale, associated with collisions with the tips of the prolate actinide nuclei, shows a rapid increase in probability with increasing projectile charge, the transition being centered around projectile atomic number ZP=14 . For mass-symmetric fission events, deviations of angular anisotropies from expectations for fusion fission, indicating a component of slower quasifission, suggest a similar transition, but centered around ZP˜8 . Conclusions: Collisions with the tips of statically deformed prolate actinide nuclei show evidence for two distinct quasifission processes of different time scales. Their probabilities both increase rapidly with the projectile charge. The probability of fusion can be severely

Image fusion tool: Validation by phantom measurements

International Nuclear Information System (INIS)

Zander, A.; Geworski, L.; Richter, M.; Ivancevic, V.; Munz, D.L.; Muehler, M.; Ditt, H.

2002-01-01

Aim: Validation of a new image fusion tool with regard to handling, application in a clinical environment and fusion precision under different acquisition and registration settings. Methods: The image fusion tool investigated allows fusion of imaging modalities such as PET, CT, MRI. In order to investigate fusion precision, PET and MRI measurements were performed using a cylinder and a body contour-shaped phantom. The cylinder phantom (diameter and length 20 cm each) contained spheres (10 to 40 mm in diameter) which represented 'cold' or 'hot' lesions in PET measurements. The body contour-shaped phantom was equipped with a heart model containing two 'cold' lesions. Measurements were done with and without four external markers placed on the phantoms. The markers were made of plexiglass (2 cm diameter and 1 cm thickness) and contained a Ga-Ge-68 core for PET and Vitamin E for MRI measurements. Comparison of fusion results with and without markers was done visually and by computer assistance. This algorithm was applied to the different fusion parameters and phantoms. Results: Image fusion of PET and MRI data without external markers yielded a measured error of 0 resulting in a shift at the matrix border of 1.5 mm. Conclusion: The image fusion tool investigated allows a precise fusion of PET and MRI data with a translation error acceptable for clinical use. The error is further minimized by using external markers, especially in the case of missing anatomical orientation. Using PET the registration error depends almost only on the low resolution of the data

Theoretical model of the probability of fusion between deuterons within deformed lattices with microcracks at room temperature

International Nuclear Information System (INIS)

Frisone, Fulvio

2006-01-01

In this work we wish to demonstrate that a reaction path as the following dislocations, deformations due to thermodynamic stress and, finally, microcrack occurrence, can enhance the process of fusion of the deuterons introduced into the lattice by deuterium loading (F. Frisone, Can variations in temperature influence deuteron interaction within crystalline lattices?, Nuovo Cimento D, 18, 1279 (1996)). In fact, calculating the rate of deuteron-plasmon-deuteron fusion within a microcrack, showed, together with an enhancement of the tunneling effect, an increase of at least 2 - 3 orders of magnitude compared to the probability of fusion on the no deformed lattice. In fact, strong electric fields can take place in the microcrack and the deuterons are accelerated to the energy which is enough for the D-D tunnelling (M. Rabinowitz, High temperature superconductivity and cold fusion, Mod. Phys, Lett. B, 4, 233 (1990); J. Price Hirt and J. Lothe, Theory of Dislocation (McGraw Hill); Z. Phys., 457, 156 (1960)). These phenomena open the way to the theoretical hypothesis that a kind of chain reaction, catalyzed by the microcracks produced in the structure as a result of deuterium loading, can favour tho process of deuteron-plasmon fusion (N. W. Ashcroft and N. D. Mermin (Eds.), Solid State Physics, Chapter 25 (Saunders College, Philadelphia, 1972, pp. 492-509)

MHD deceleration of fusion reaction products

International Nuclear Information System (INIS)

Chow, S.; Bohachevsky, I.O.

1979-04-01

The feasibility of magnetohydrodynamic (MHD) deceleration of fuel pellet debris ions exiting from an inertial confinement fusion (ICF) reactor cavity is investigated using one-dimensional flow equations. For engineering reasons, induction-type devices are emphasized; their performance characteristics are similar to those of electrode-type decelerators. Results of the analysis presented in this report indicate that MHD decelerators can be designed within conventional magnet technology to not only decelerate the high-energy fusion pellet debris ions but also to produce some net electric power in the process

Direct projectile break up its relation to the astrophysically revelant fusion reactions

International Nuclear Information System (INIS)

Bertulani, C.A.; Hussein, M.S.

1990-05-01

The break-up into two pieces of weakly bound nuclei passing by the Coulomb field of a large Z nucleus can provide useful information on the inverse fusion reactions which are important for the elemental formation in the stars. However, the nuclear interaction complicates considerably the extraction of such information. A study is made of the contributions of the Coulomb and nuclear interaction to the process, showing when the Coulomb break-up prevails and how a reliable separation of multipolarities can be done. (author)

Cold, muon-catalyzed fusion - just another swarm experiment?

International Nuclear Information System (INIS)

Robson, R.E.

1992-01-01

The paper briefly reviewed the muon-catalyzed fusion cycle and indicated how it may be likened to a swarm experiment. In particular, it has been pointed out that an external electric field can influence the properties of a muon swarm (and reactive derivatives), just as it can for ion and electron swarms. Since n 0 is typically around liquid hydrogen densities, very large fields, E≥10 9 V/m, would be required to achieve the desired outcome. This is presently achievable in small regions of intense laser focus, but it remains to be seen whether muon-catalyzed fusion experiments can actually be influenced in this way. 20 refs., 4 figs

Theory of nuclear reactions with participation of slow charged particles in solids

International Nuclear Information System (INIS)

Barts, B.I.; Barts, D.B.; Grinenko, A.A.

1992-01-01

In the last two years, there has been a sharp increase of interest in various aspects of the interaction of nuclear particles in solids. This is due, above all, to the sensational reports of the possibility that deuteron fusion reactions take place at normal temperatures. At the present time, it is clear that, among the various factors, an important role for the understanding of this remarkable phenomenon is played by crystal fields that significantly change the tail of the Coulomb barrier and, thus, its penetrability. Here, in connection with the problem of the cold fusion of deuterons, an analysis is made of the influence of screening of the deuteron charges by electrons of the crystal on the penetrability of the Coulomb barrier. A study is made of the reaction-enhancement method in the case when the deuterons move in the general crystal potential well near one of the minima of the crystal potential

The fusion-fission process in the reaction {sup 34}S+{sup 186}W near the interaction barrier

Energy Technology Data Exchange (ETDEWEB)

Harca, I. M. [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, (FLNR JINR) Dubna, Russia and Faculty of Physics, University of Bucharest - P.O. Box MG 11, RO 77125, Bucharest-Magurele (Romania); Dmitriev, S.; Itkis, J.; Kozulin, E. M.; Knyazheva, G.; Loktev, T.; Novikov, K. [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, (FLNR JINR) Dubna (Russian Federation); Azaiez, F.; Gottardo, A.; Matea, I.; Verney, D. [IPN, CNRS/IN2P3, Univ. Paris-Sud, 91405 Orsay (France); Chubarian, G. [Cyclotron Institute, Texas A and M University, College Station, TX 77843-3366 (United States); Hanappe, F. [Universite Libre de Bruxelles (ULB), Bruxelles (Belgium); Piot, J.; Schmitt, C. [GANIL, CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); Trzaska, W. H. [Accelerator Laboratory of University of Jyväskylä (JYFL), Jyväskylä (Finland); Vardaci, E. [Dipartamento di Scienze Fisiche and INFN (INFN-Na), Napoli (Italy)

2015-02-24

The reaction {sup 34}S+{sup 186}W at E{sub lab}=160 MeV was investigated with the aim of diving into the features of the fusion-fission process. Gamma rays in coincidence with binary reaction fragments were measured using the high efficiency gamma-ray spectrometer ORGAM at the TANDEM Accelerator facility of I.P.N., Orsay, and the time-of-flight spectrometer for fission fragments (FF) registration CORSET of the Flerov Laboratory of Nuclear Reactions (FLNR), Dubna. The coupling of the ORGAM and CORSET setups offers the unique opportunity of extracting details for characterizing the fusion-fission process and gives information regarding production of neutron-rich heavy nuclei. The FF–γ coincidence method is of better use then the γ – γ coincidence method when dealing with low statistic measurements and also offers the opportunity to precisely correct the Dopler shift for in-flight emitted gamma rays. Evidence of symmetric and asymmetric fission modes were observed in the mass and TKE distributions, occurring due to shell effects in the fragments. Coincident measurements allow for discrimination between the gamma rays by accepting a specific range within the mass distribution of the reaction products. Details regarding the experimental setup, methods of processing the acquisitioned data and preliminary results are presented.

Fusion reaction yield in focused discharges with variable energy and plasma fine structure

International Nuclear Information System (INIS)

Bortolotti, A.; Brzosko, J.S.; Chiara, P. De; Kilic, H.; Mezzetti, F.; Nardi, V.; Powell, C.; Wang, J.

1992-01-01

The same linear correlation between the distribution parameters (ΔT and Max ΔV) of the radial current density J between electrodes and the fusion reaction yield per pulse, Y, in the plasma focus (PF) pinch was quantitatively determined from different PF machines. Contact prints of current-sheath fragments (CSF) ejected from the pinch are obtained from 2.5-MeV-D + ions. CSF's show the same submillimetric fine structure of the pinch. (author) 3 refs., 2 tabs

The fusion rate in the transmission resonance model

International Nuclear Information System (INIS)

Jaendel, M.

1992-01-01

Resonant transmission of deuterons through a chain of target deuterons in a metal matrix has been suggested as an explanation for the cold fusion phenomena. In this paper the fusion rate in such transmission resonance models is estimated, and the basic physical constraints are discussed. The dominating contribution to the fusion yield is found to come from metastable states. The fusion rate is well described by the Wentzel-Kramer-Brillouin approximation and appears to be much too small to explain the experimental anomalies

Fusion breeder: its potential role and prospects

International Nuclear Information System (INIS)

Lee, J.D.

1981-01-01

The fusion breeder is a concept that utilizes 14 MeV neutrons from D + T → n(14.1 MeV) + α(3.5 MeV) fusion reactions to produce more fuel than the tritium (T) needed to sustain the fusion process. This excess fuel production capacity is used to produce fissile material (Pu-239 or U-233) for subsequent use in fission reactors. We are concentrating on a class of blankets we call fission suppressed. The blanket is the region surrounding the fusion plasma in which fusion neutrons interact to produce fuel and heat. The fission-suppressed blanket uses non-fission reactions (mainly (n,2n) or (n,n't)) to generate excess neutrons for the production of net fuel. This is in contrast to the fast fission class of blankets which use (n,fiss) reactions to generate excess neutrons. Fusion reactors with fast fission blankets are commony known as fusion-fission hybrids because they combine fusion and fission in the same device

Laser induced photonuclear and fusion-reactions

International Nuclear Information System (INIS)

LoDato, V.A.

1977-01-01

The energy release from the fusion-fission pellets is demonstrated. It is shown that the coupling of the fusion-fission process is extremely efficient provided one can obtain the proper compression heating. The pellet of an outer core of (Li6D-Li6T) with an inner core of U238 is shown to be an efficient and practical fuel and can be ignited by the present generation of lasers to produce thermonuclear burn. The demonstration of the efficiency for photonuclear and photofission pellets is shown. However no suitable gamma ray source exists at present to initiate these processes. (orig.) [de

Reaction and fusion cross sections for 32S on 27Al and 48Ti

International Nuclear Information System (INIS)

Porto, F.; Sambataro, S.; Kusterer, K.; Liu Ken Pao; Doukellis, G.; Harney, H.L.

1981-01-01

Elastic scattering and evaporation residues have been measured for the system 32 S + 27 Al at Esub(c)sub(.)sub(m)sub(.) = 66.4, 73.2 MeV and 32 S + 48 Ti at Esub(c)sub(.)sub(m)sub(.) = 96.0 MeV. Reaction cross sections have been obtained by use of the optical theorem and are found to be about 60% larger than the fusion cross sections. (orig.)

8th International School of Fusion Reactor Technology "Ettore Majorana"

CERN Document Server

Leotta, G G; Muon-catalyzed fusion and fusion with polarized nuclei

1988-01-01

The International School of Fusion Reactor Technology started its courses 15 years ago and since then has mantained a biennial pace. Generally, each course has developed the subject which was announced in advance at the closing of the previous course. The subject to which the present proceedings refer was chosen in violation of that rule so as to satisfy the recent and diffuse interest in cold fusion among the main European laboratories involved in controlled thermonuclear research (CTR). In the second half of 1986 we started to prepare a workshop aimed at assessing the state of the art and possibly of the perspectives of muon- catalyzed fusion. Research in this field has recently produced exciting experimental results open to important practical applications. We thought it worthwhile to consider also the beneficial effects and problems of the polarization ofthe nuclei in both cold and thermonuclear fusion. In preparing the 8th Course on Fusion Reactor Technology, it was necessary to abandon the tradi...

Muon-catalyzed fusion revisited

Energy Technology Data Exchange (ETDEWEB)

Anon.

1984-12-15

A negative muon can induce nuclear fusion in the reaction of deuteron and triton nuclei giving a helium nucleus, a neutron and an emerging negative muon. The muon forms a tightlybound deuteron-triton-muon molecule and fusion follows in about 10{sup -12}s. Then the muon is free again to induce further reactions. Thus the muon can serve as a catalyst for nuclear fusion, which can proceed without the need for the high temperatures which are needed in the confinement and inertial fusion schemes. At room temperature, up to 80 fusions per muon have recently been observed at the LAMPF machine at Los Alamos, and it is clear that this number can be exceeded. These and other results were presented at a summer Workshop on Muon-Catalyzed Fusion held in Jackson, Wyoming. Approximately fifty scientists attended from Austria, Canada, India, Italy, Japan, South Africa, West Germany, and the United States. The Workshop itself is symbolic of the revival of interest in this subject.

ALKALI FUSION OF ROSETTA ZIRCON

International Nuclear Information System (INIS)

DAHER, A.

2008-01-01

The decomposition of Rosetta zircon by fusion with different types of alkalis has been investigated. These alkalis include sodium hydroxide, potassium hydroxide and eutectic mixture of both. The influences of the reaction temperature, zircon to alkalis ratio, fusion time and the stirring of the reactant on the fusion reaction have been evaluated. The obtained results favour the decomposition of zircon with the eutectic alkalis mixture by a decomposition efficiency of 96% obtained at 500 0 C after one hour

Nuclear fusion: power for the next century

International Nuclear Information System (INIS)

1980-05-01

The basis of fusion reactions is outlined, with special reference to deuterium and tritium (from lithium, by neutron reaction) as reactants, and the state of research worldwide is indicated. The problems inherent in fusion reactions are discussed, plasma is defined, and the steps to be taken to generate electricity from controlled nuclear fusion are stated. Methods of plasma heating and plasma confinement are considered, leading to a description of the tokamak plasma confinement system. Devices under construction include the JET (Joint European Torus) Undertaking in the UK. Plans and possibilities for fusion reactors are discussed. (U.K.)

Barriers to fusion

International Nuclear Information System (INIS)

Berriman, A.C.; Butt, R.D.; Dasgupta, M.; Hinde, D.J.; Morton, C.R.; Newton, J.O.

1999-01-01

The fusion barrier is formed by the combination of the repulsive Coulomb and attractive nuclear forces. Recent research at the Australian National University has shown that when heavy nuclei collide, instead of a single fusion barrier, there is a set of fusion barriers. These arise due to intrinsic properties of the interacting nuclei such deformation, rotations and vibrations. Thus the range of barrier energies depends on the properties of both nuclei. The transfer of matter between nuclei, forming a neck, can also affect the fusion process. High precision data have been used to determine fusion barrier distributions for many nuclear reactions, leading to new insights into the fusion process

Hyperenhanced Li - Li Chemonuclear Fusion

International Nuclear Information System (INIS)

Ikegami, Hidetsugu

2006-01-01

A new fusion scheme, the Li - Li chemonuclear fusion is presented, where nuclear fusion reactions are linked to atomic fusion reactions. Lithium ions are implanted on a surface of metallic Li liquid at an energy of nuclear stopping (several keV/amu). The ions collide slowly with liquid Li atoms without electronic excitation and lead to the Li - Li chemonuclear fusion through the formation of united atoms or quasi-C atoms at their turning points. Inside the quasi-atoms twin nuclei are confined within respective sub-pm scale spheres of zero-point oscillation and form themselves into ultradense intermediate nuclear complexes. Their density is million times as large as the solar interior density and close to densities of white dwarfs or white-dwarf progenitors of supernovae. This confinement of nuclear complexes is enormously prolonged towards the pycno-nuclear reactions induced by the zero-point oscillation under the presence of thermodynamic force specified by the Gibbs energy change in the quasi-atom formation in the liquid. Resulted rate enhancement of nuclear fusion by a factor of 10 48 has been anticipated. The enhancement is also argued in connection with the Bose-Einstein condensation

Study of the role of complete fusion in the reaction of /sup 48/Ca and /sup 56/Fe with cerium and terbium. [Cross sections, yield curves, tables

Energy Technology Data Exchange (ETDEWEB)

Morrissey, D.J.

1978-05-01

/sup 48/Ca and /sup 56/Fe beams from the Super HILAC accelerator were used to irradiate thick metal foils of cerium and terbium. Product gamma ray activities were detected offline and individual products were identified by half-life, gamma ray energy and gamma ray abundances. The production cross sections were iteratively fit to charge and mass dispersions to allow correction for parent decay and calculation of mass yields. From the mass yield curves contributions from quasielastic transfer, deep inelastic transfer and complete fusion reaction mechanisms were interred. Complete fusion was made up on contributions from both evaporation residue and fusion-fission products for the /sup 48/Ca induced reactions. However, only fusion-fission products were detected in the /sup 56/Fe induced reactions. Critical angular momenta for fusion were found to be 82 +- 8 h for /sup 48/Ca + /sup 159/Tb and 34 +- 5 h for /sup 56/Fe + /sup 140/Ce, which can be compared with 53 +- 8 h for /sup 12/C + /sup 197/Au (Natowitz, 1970) and 86 +- 5 h for /sup 40/Ar + /sup 165/Ho (Hanappe, 1973). All of these reactions lead to essentially the same compound nucleus and seem to show the dramatic decline in complete fusion for heavy ions larger than /sup 40/Ar. The prediction of this decline was found to be beyond the model calculations of Bass and the critical distance approach of Glas and Mosel.

Fusion, reaction and break-up cross sections of weakly bound projectiles on 64Zn

International Nuclear Information System (INIS)

Gomes, P.R.S.; Padron, I.; Rodriguez, M.D.; Marti, G.V.; Anjos, R.M.; Lubian, J.; Veiga, R.; Liguori Neto, R.; Crema, E.; Added, N.; Chamon, L.C.; Fernandez Niello, J.O.; Capurro, O.A.; Pacheco, A.J.; Testoni, J.E.; Abriola, D.; Arazi, A.; Ramirez, M.; Hussein, M.S.

2004-01-01

We present new measurements and a general discussion of the behavior of the fusion, break-up and reaction cross sections of different projectiles on the same target 64 Zn, at near and above barrier energies. The projectiles are the tightly bound 16 O, the stable weakly bound 6 Li, 7 Li and 9 Be and the radioactive very weakly bound 6 He nuclei. We also compare the results with the ones for heavier targets

Roles of multi-step transfer in fusion process induced by heavy-ion reactions

International Nuclear Information System (INIS)

Imanishi, B.; Oertzen, W. von.

1993-06-01

In nucleus-nucleus collisions of the systems, 12 C+ 13 C and 13 C+ 16 O- 12 C+ 17 O, the effects of the multi-step transfers and inelastic excitations on the fusion cross sections are investigated in the framework of the coupled-reaction-channel (CRC) method. Strong CRC effects of the multi-step processes are observed. Namely, the valence neutron in 13 C or 17 O plays an important role in the enhancement of the fusion. The potential barrier is effectively lowered with the formation of the covalent molecule of the configuration, 12 C+n+ 12 C or 12 C+n+ 16 O. In the analyses of the system 12 C+ 13 C, however, it is still required to introduce core-core optical potential of lower barrier height in the state of the positive total parity. This could be due to the neck formation with the nucleons contained in two core nuclei. (author)

Fusion barrier distributions and fission anisotropies

International Nuclear Information System (INIS)

Hinde, D.J.; Morton, C.R.; Dasgupta, M.; Leigh, J.R.; Lestone, J.P.; Lemmon, R.C.; Mein, J.C.; Newton, J.O.; Timmers, H.; Rowley, N.; Kruppa, A.T.

1995-01-01

Fusion excitation functions for 16,17 O+ 144 Sm have been measured to high precision. The extracted fusion barrier distributions show a double-peaked structure interpreted in terms of coupling to inelastic collective excitations of the target. The effect of the positive Q-value neutron stripping channel is evident in the reaction with 17 O. Fission and evaporation residue cross-sections and excitation functions have been measured for the reaction of 16 O+ 208 Pb and the fusion barrier distribution and fission anisotropies determined. It is found that the moments of the fusion l-distribution determined from the fusion and fission measurements are in good agreement. ((orig.))

Fusion events

International Nuclear Information System (INIS)

Aboufirassi, M; Angelique, J.C.; Bizard, G.; Bougault, R.; Brou, R.; Buta, A.; Colin, J.; Cussol, D.; Durand, D.; Genoux-Lubain, A.; Horn, D.; Kerambrun, A.; Laville, J.L.; Le Brun, C.; Lecolley, J.F.; Lefebvres, F.; Lopez, O.; Louvel, M.; Meslin, C.; Metivier, V.; Nakagawa, T.; Peter, J.; Popescu, R.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Wieloch, A.; Yuasa-Nakagawa, K.

1998-01-01

The fusion reactions between low energy heavy ions have a very high cross section. First measurements at energies around 30-40 MeV/nucleon indicated no residue of either complete or incomplete fusion, thus demonstrating the disappearance of this process. This is explained as being due to the high amount o energies transferred to the nucleus, what leads to its total dislocation in light fragments and particles. Exclusive analyses have permitted to mark clearly the presence of fusion processes in heavy systems at energies above 30-40 MeV/nucleon. Among the complete events of the Kr + Au reaction at 60 MeV/nucleon the majority correspond to binary collisions. Nevertheless, for the most considerable energy losses, a class of events do occur for which the detected fragments appears to be emitted from a unique source. These events correspond to an incomplete projectile-target fusion followed by a multifragmentation. Such events were singled out also in the reaction Xe + Sn at 50 MeV/nucleon. For the events in which the energy dissipation was maximal it was possible to isolate an isotropic group of events showing all the characteristics of fusion nuclei. The fusion is said to be incomplete as pre-equilibrium Z = 1 and Z = 2 particles are emitted. The cross section is of the order of 25 mb. Similar conclusions were drown for the systems 36 Ar + 27 Al and 64 Zn + nat Ti. A cross section value of ∼ 20 mb was determined at 55 MeV/nucleon in the first case, while the measurement of evaporation light residues in the last system gave an upper limit of 20-30 mb for the cross section at 50 MeV/nucleon

Incomplete fusion reactions in Ho

Indian Academy of Sciences (India)

model [9], promptly emitted particles (PEPs) model [10], exciton model [11], etc. During the past decade a large number of reports have appeared [12–14] showing the occurrence of incomplete fusion at beam energy just above the Coulomb barrier. Recoil range distribution (RRD) measurements are particularly attractive for ...

Energy from inertial fusion

International Nuclear Information System (INIS)

1995-03-01

This book contains 22 articles on inertial fusion energy (IFE) research and development written in the framework of an international collaboration of authors under the guidance of an advisory group on inertial fusion energy set up in 1991 to advise the IAEA. It describes the actual scientific, engineering and technological developments in the field of inertial confinement fusion (ICF). It also identifies ways in which international co-operation in ICF could be stimulated. The book is intended for a large audience and provides an introduction to inertial fusion energy and an overview of the various technologies needed for IFE power plants to be developed. It contains chapters on (i) the fundamentals of IFE; (ii) inertial confinement target physics; (iii) IFE power plant design principles (requirements for power plant drivers, solid state laser drivers, gas laser drivers, heavy ion drivers, and light ion drivers, target fabrication and positioning, reaction chamber systems, power generation and conditioning and radiation control, materials management and target materials recovery), (iv) special design issues (radiation damage in structural materials, induced radioactivity, laser driver- reaction chamber interfaces, ion beam driver-reaction chamber interfaces), (v) inertial fusion energy development strategy, (vi) safety and environmental impact, (vii) economics and other figures of merit; (viii) other uses of inertial fusion (both those involving and not involving implosions); and (ix) international activities. Refs, figs and tabs

A D-D/D-T fusion reaction based neutron generator system for liver tumor BNCT

International Nuclear Information System (INIS)

Koivunoro, H.; Lou, T.P.; Leung, K. N.; Reijonen, J.

2003-01-01

Boron-neutron capture therapy (BNCT) is an experimental radiation treatment modality used for highly malignant tumor treatments. Prior to irradiation with low energetic neutrons, a 10B compound is located selectively in the tumor cells. The effect of the treatment is based on the high LET radiation released in the 10 B(n,α) 7 Li reaction with thermal neutrons. BNCT has been used experimentally for brain tumor and melanoma treatments. Lately applications of other severe tumor type treatments have been introduced. Results have shown that liver tumors can also be treated by BNCT. At Lawrence Berkeley National Laboratory, various compact neutron generators based on D-D or D-T fusion reactions are being developed. The earlier theoretical studies of the D-D or D-T fusion reaction based neutron generators have shown that the optimal moderator and reflector configuration for brain tumor BNCT can be created. In this work, the applicability of 2.5 MeV neutrons for liver tumor BNCT application was studied. The optimal neutron energy for external liver treatments is not known. Neutron beams of different energies (1eV < E < 100 keV) were simulated and the dose distribution in the liver was calculated with the MCNP simulation code. In order to obtain the optimal neutron energy spectrum with the D-D neutrons, various moderator designs were performed using MCNP simulations. In this article the neutron spectrum and the optimized beam shaping assembly for liver tumor treatments is presented

Nuclear science experiments with a bright neutron source from fusion reactions on the OMEGA Laser System

Science.gov (United States)

Forrest, C. J.; Knauer, J. P.; Schroeder, W. U.; Glebov, V. Yu.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; Sickles, M.; Stoeckl, C.; Szczepanski, J.

2018-04-01

Subnanosecond impulses of 1013 to 1014 neutrons, produced in direct-drive laser inertial confinement fusion implosions, have been used to irradiate deuterated targets at the OMEGA Laser System (Boehly et al., 1997). The target compounds include heavy water (D2O) and deuterated benzene (C6D6). Yields and energy spectra of neutrons from D(n,2n)p to study the breakup reaction have been measured at a forward angle of θlab = 3 .5∘ ± 3.5° with a sensitive, high-dynamic-range neutron time-of-flight spectrometer to infer the double-differential breakup cross section d2 σ/dE d Ω for 14-MeV D-T fusion neutrons.

Possibilities of achieving fusion reaction with a 4{pi} focusing system

Energy Technology Data Exchange (ETDEWEB)

Barsanti, G; Barsella, B; Camerini, M; Federighi, U; Musumeci, L; Talini, N [CAMEN., Leghorn (Italy)

1958-07-01

The 4{pi} focusing by means of an electromagnetic field is analysed. The following points considered: (a) The general solutions of system for equations of motion of a mass m with charge +e valid for arbitrary initial conditions. This is necessary for the consideration of imperfectly focused primary trajectories, of the effect of collisions in the vicinity of the origin and of ions produced in the neutral gas which diffuses into the reaction chamber. (b) Investigation of the primary ion injection system, of the density of the ions in the chamber and of the energy balance as a matter of principle. (c) The experimental apparatus needed for 4{pi} focusing of deuterons and a sketch of a fusion reactor.

Dynamic loadings of sodium-water reactions in LMFBR and fusion power designs

Energy Technology Data Exchange (ETDEWEB)

Chan, C. K.

1977-07-01

In liquid metal fast breeder reactor and lithium cooled fusion reactor, a sodium loop is being proposed to transfer heat from the primary coolant loop to the steam turbine cycle. Although by careful design and quality assurance programs, the probability for steam generator tube failure can be minimized, failure will still occur. The direct contact of sodium and water would cause a chemical reaction where hydrogen and sodium compounds are produced. This paper presents an evaluation of the potential hazards as a result of such a reaction. An analytical method is developed to investigate the extent of the reaction zone and the propagation of the pressure wave in the sodium system. In the calculation, the chemical reaction is assumed to be instantaneous, governed by the equation 2Na(l)+H/sub 2/O(l)..-->..Na/sub 2/O(l)+H/sub 2/(g)+31.4 K cal/gm. mole. Both the temperature and pressure rise in the reaction zone can be established from the energy balance and the equation of state for the gaseous product. As a consequence of the energy released, the chemical products suddenly expand with a high velocity. The expansion also generates a shock wave in both the water and the sodium systems. Results indicate that the reaction zone can expand in a rate of 1500 ft/sec and a shock wave with initial strength of 2300 atmospheres propagates with a speed of 8000 ft/sec into the sodium system. The propagating characteristics of the shock wave are obtained by solving the basic fluid equations. The shock wave decays rapidly, in the neighborhood of milliseconds, as soon as the reaction zone stops to expand. The decrease in the reaction zone pressure allows more water to react with the sodium and a second pulse is generated.

Dynamic loadings of sodium-water reactions in LMFBR and fusion power designs

International Nuclear Information System (INIS)

Chan, C.K.

1977-01-01

In liquid metal fast breeder reactor and lithium cooled fusion reactor, a sodium loop is being proposed to transfer heat from the primary coolant loop to the steam turbine cycle. Although by careful design and quality assurance programs, the probability for steam generator tube failure can be minimized, failure will still occur. The direct contact of sodium and water would cause a chemical reaction where hydrogen and sodium compounds are produced. This paper presents an evaluation of the potential hazards as a result of such a reaction. An analytical method is developed to investigate the extent of the reaction zone and the propagation of the pressure wave in the sodium system. In the calculation, the chemical reaction is assumed to be instantaneous, governed by the equation 2Na(l)+H 2 O(l)→Na 2 O(l)+H 2 (g)+31.4 K cal/gm. mole. Both the temperature and pressure rise in the reaction zone can be established from the energy balance and the equation of state for the gaseous product. As a consequence of the energy released, the chemical products suddenly expand with a high velocity. The expansion also generates a shock wave in both the water and the sodium systems. Results indicate that the reaction zone can expand in a rate of 1500 ft/sec and a shock wave with initial strength of 2300 atmospheres propagates with a speed of 8000 ft/sec into the sodium system. The propagating characteristics of the shock wave are obtained by solving the basic fluid equations. The shock wave decays rapidly, in the neighborhood of milliseconds, as soon as the reaction zone stops to expand. The decrease in the reaction zone pressure allows more water to react with the sodium and a second pulse is generated

Investigations and calculations toward increasing the efficiency of muon catalyzed fusion

International Nuclear Information System (INIS)

Monkhorst, H.J.

1989-11-01

A brief summary of results during this report period is given. Some of the topics investigated includes: (1) calculations of sticking fractions and d-t fusion from dtμ(JV) states, (2) ddμ sticking fractions, (3) the reactivation coefficient in d-t fusion, (4) fusion rates for all XYμ(JV)(JV=0,1), (5) nuclear effects on energy shifts and fusion rates for (J=O) states of dtμ, (6) and some comments on cold fusion

Fusion reaction cross-sections using the Wong model within Skyrme energy density based semiclassical extended Thomas Fermi approach

Energy Technology Data Exchange (ETDEWEB)

Kumar, Raj, E-mail: rajkumarfzr@gmail.com [Department of Physics, Panjab University, Chandigarh-160014 (India); School of Physics and Material Science, Thapar University, Patiala-147004 (India); Sharma, Manoj K. [School of Physics and Material Science, Thapar University, Patiala-147004 (India); Gupta, Raj K. [Department of Physics, Panjab University, Chandigarh-160014 (India)

2011-11-15

First, the nuclear proximity potential, obtained by using the semiclassical extended Thomas Fermi (ETF) approach in Skyrme energy density formalism (SEDF), is shown to give more realistic barriers in frozen density approximation, as compared to the sudden approximation. Then, taking advantage of the fact that, in ETF method, different Skyrme forces give different barriers (height, position and curvature), we use the l-summed extended-Wong model of Gupta and collaborators (2009) under frozen densities approximation for calculating the cross-sections, where the Skyrme force is chosen with proper barrier characteristics, not-requiring additional 'barrier modification' effects (lowering or narrowing, etc.), for a best fit to data at sub-barrier energies. The method is applied to capture cross-section data from {sup 48}Ca + {sup 238}U, {sup 244}Pu, and {sup 248}Cm reactions and to fusion-evaporation cross-sections from {sup 58}Ni + {sup 58}Ni, {sup 64}Ni + {sup 64}Ni, and {sup 64}Ni + {sup 100}Mo reactions, with effects of deformations and orientations of nuclei included, wherever required. Interestingly, whereas the capture cross-sections in Ca-induced reactions could be fitted to any force, such as SIII, SV and GSkI, by allowing a small change of couple of units in deduced l{sub max}-values at below-barrier energies, the near-barrier data point of {sup 48}Ca + {sup 248}Cm reaction could not be fitted to l{sub max}-values deduced for below-barrier energies, calling for a check of data. On the other hand, the fusion-evaporation cross-sections in Ni-induced reactions at sub-barrier energies required different Skyrme forces, representing 'modifications of the barrier', for the best fit to data at all incident center-of-mass energies E{sub c.m.}'s, displaying a kind of fusion hindrance at sub-barrier energies. This barrier modification effect is taken into care here by using different Skyrme forces for reactions belonging to different regions of

Fusion reactors - types - problems

International Nuclear Information System (INIS)

Schmitter, K.H.

1979-07-01

A short account is given of the principles of fusion reactions and of the expected advantages of fusion reactors. Descriptions are presented of various Tokamak experimental devices being developed in a number of countries and of some mirror machines. The technical obstacles to be overcome before a fusion reactor could be self-supporting are discussed. (U.K.)

Material for fusion reactor

International Nuclear Information System (INIS)

Abhishek, Anuj; Ranjan, Prem

2011-01-01

To make nuclear fusion power a reality, the scientists are working restlessly to find the materials which can confine the power generated by the fusion of two atomic nuclei. A little success in this field has been achieved, though there are still miles to go. Fusion reaction is a special kind of reaction which must occur at very high density and temperature to develop extremely large amount of energy, which is very hard to control and confine within using the present techniques. As a whole it requires the physical condition that rarely exists on the earth to carry out in an efficient manner. As per the growing demand and present scenario of the world energy, scientists are working round the clock to make effective fusion reactions to real. In this paper the work presently going on is considered in this regard. The progress of the Joint European Torus 2010, ITER 2005, HiPER and minor works have been studied to make the paper more object oriented. A detailed study of the technological and material requirement has been discussed in the paper and a possible suggestion is provided to make a contribution in the field of building first ever nuclear fusion reactor

Cluster correlation effects in 12C+12C and 14N+10B fusion-evaporation reactions

Directory of Open Access Journals (Sweden)

Morelli L.

2015-01-01

Full Text Available The decay of highly excited states of 24Mg is studied in fusion evaporation events completely detected in charge in the reactions 12C+12C and 14N+10B at 95 and 80 MeV incident energy respectively. The comparison of light charged particles measured spectra with statistical model predictions suggests that the dominant reaction mechanism is compound nucleus (CN formation and decay. However, in both reactions, a discrepancy with statistical expectations is found for α particles detected in coincidence with Carbon, Oxigen and Neon residues. The comparison between the two reactions shows that this discrepancy is only partly explained by an entrance channel effect. Evidence for cluster correlations in excited 24Mg CN is suggested by the comparison between the measured and calculated branching ratios for the channels involving α particles.

Heavy ion fusion reactions: comparison among different models

Energy Technology Data Exchange (ETDEWEB)

Canto, L F; Carlson, B V; Hussein, M S

1988-03-01

A comparison among different ion fusion models is presented. In particular, the multistep aspects of the recently proposed Dinucleus Doorway Model are made explicit and the model is confronted with other compound nucleus limitation models. It is suggested that the latter models provide effective one-step descriptions of heavy ion fusion.

Influence of fragment deformation and orientation on compact configuration of odd-Z superheavy nuclei

International Nuclear Information System (INIS)

Gurjit Kaur; Sandhu, Kirandeep; Sharma, Manoj K.

2016-01-01

The synthesis of heavy and superheavy nuclei is generally carried out by using hot and cold fusion reaction mechanisms. It has been noticed that, the cold fusion reactions occur at relatively low excitation energies (E*_C_N ∼ 10-20 MeV) whereas, the hot fusion reactions occur at excitation energies of E*_C_N ∼ 30- 50 MeV. The fusion mechanism is quite different in both the processes. In the cold fusion process, the interaction of spherical targets (Pb and Bi) with deformed light mass projectiles occurs. On the other hand, the fusion of deformed actinide targets with spherical "4"8Ca projectile characterize the hot interaction processes. Hence the deformations and orientations of targets and projectiles play extremely important role in the superheavy fusion process. The present analysis is carried out to aggrandize the work of which illustrate the role of deformations and orientations on even superheavy nuclei. Here, we extend this analysis for odd superheavy nuclei. It is relevant to note that the temperature and angular momentum effects are not included in the present analysis

Muon-catalyzed fusion theory - introduction and review

International Nuclear Information System (INIS)

Cohen, J.S.

1990-01-01

Muon-catalyzed fusion (μCF) has proved to be a fruitful subject for basic physics research as well as a source of cold nuclear fusion. Experiments have demonstrated that over 100 fusions per muon can be catalyzed by formation of the dtμ molecules in mixtures of deuterium and tritium. After a brief review of the subject's history, the dtμ catalysis cycle and the principle relations used in its analysis are described. Some of the important processes in the μCF cycle are then discussed. Finally, the status of current research is appraised. (author)

The influence of transfer reactions on the sub-barrier fusion enhancement in the systems {sup 58.64}Ni +, {sup 92,100}Mo

Energy Technology Data Exchange (ETDEWEB)

Rehm, K.E.; Jiang, C.L.; Esbensen, H. [and others

1995-08-01

High resolution experiments performed during the past few years demonstrated that the various reaction modes occurring in heavy ion collisions can strongly influence each other. This interrelation of the different reaction modes brings a nuclear structure dependence to the fusion and deep-inelastic channels that were previously described in the framework of pure statistical models. In order to fully understand the interrelation between these reaction channels, a complete set of measurements including elastic and inelastic scattering, few-nucleon transfer and fusion is required. In continuation of our earlier measurements of the fusion cross sections in the system {sup 58,64}Ni + {sup 92,100}Mo we finished the studies of the quasielastic process in these systems. The experiments were done in inverse reaction kinematics using the split-pole spectrograph with its hybrid focal-plane detector for particle identification. The experiments with {sup 100}Mo beams were performed previously. First test runs with {sup 92}Mo showed the possible interference with {sup 98}Mo ions which could be eliminated by using the 13{sup +} charge state from the ECR source. The data from these experiments were completely analyzed. The smallest transfer cross sections are observed for the systems {sup 64}Ni + {sup 100}Mo and {sup 58}Ni + {sup 92}Mo, i.e., the most neutron-rich and neutron-deficient systems, respectively. For the other systems, {sup 64}Ni + {sup 92}Mo and {sup 58}Ni + {sup 100}Mo, the transfer cross sections at energies close to the barrier are about of equal magnitude. This observation does not correlate with the deviation of the experimental fusion cross sections from the coupled-channels predictions. While for {sup 58}Ni + {sup 100}Mo discrepancies between the experimental and theoretical fusion cross sections are observed, the system {sup 64}Ni + {sup 92}Mo which shows about the same transfer yields, is quite well described by the coupled-channels calculations.

Controlled Nuclear Fusion.

Science.gov (United States)

Glasstone, Samuel

This publication is one of a series of information booklets for the general public published by The United States Atomic Energy Commission. Among the topics discussed are: Importance of Fusion Energy; Conditions for Nuclear Fusion; Thermonuclear Reactions in Plasmas; Plasma Confinement by Magnetic Fields; Experiments With Plasmas; High-Temperature…

Sensitivity of fusion and quasi-elastic barrier distributions of {sub 16}O+{sub 144}Sm reaction on the coupling radius parameter

Energy Technology Data Exchange (ETDEWEB)

Zamrun, Muhammad; Usman, Ida; Variani, Viska Inda [Department of Physics, Haluoleo University, Kendari, Sulawesi Tengagra, 93232 (Indonesia); Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2014-03-05

We study the heavy-ion collision at sub-barrier energies of {sub 16}O+{sub 144}Sm system using full order coupled-channels formalism. We especially investigate the sensitivity of fusion and quasi-elastic barrier distributions for this system on the coupling radius parameter. We found that the coupled-channels calculations of the fusion and the quasi-elastic barrier distributions are sensitive to the coupling radius for this reaction in contrast to the fusion and quasi-elastic cross section. Our study indicates that the larger coupling radius, i.e., r{sub coup}=1.20, is required by the experimental quasi-elastic barrier distribution. However, the experimental fusion barrier distribution compulsory the small value, i.e., r{sub coup}=1.06.

On experimental determination of characteristics of nuclear fusion reactions from mu-molecular resonance states

International Nuclear Information System (INIS)

Bystritskij, V.M.; Pen'kov, F.M.

1997-01-01

Charge-nonsymmetrical deuterium-helium muon complexes (dμHe) are studied. A method is proposed for experimentally determining the rates of nuclear fusion reactions in dμHe molecules in the J=1 and J=0 states (J is the orbital moment of the system) and the partial rates for radiative decay of these complexes in these states. Experiments are supposed to be carried out at meson factories with gaseous and cryogenic targets filled with a mixture of deuterium and helium

Muscle Reaction Time During a Simulated Lateral Ankle Sprain After Wet-Ice Application or Cold-Water Immersion.

Science.gov (United States)

Thain, Peter K; Bleakley, Christopher M; Mitchell, Andrew C S

2015-07-01

Cryotherapy is used widely in sport and exercise medicine to manage acute injuries and facilitate rehabilitation. The analgesic effects of cryotherapy are well established; however, a potential caveat is that cooling tissue negatively affects neuromuscular control through delayed muscle reaction time. This topic is important to investigate because athletes often return to exercise, rehabilitation, or competitive activity immediately or shortly after cryotherapy. To compare the effects of wet-ice application, cold-water immersion, and an untreated control condition on peroneus longus and tibialis anterior muscle reaction time during a simulated lateral ankle sprain. Randomized controlled clinical trial. University of Hertfordshire human performance laboratory. A total of 54 physically active individuals (age = 20.1 ± 1.5 years, height = 1.7 ± 0.07 m, mass = 66.7 ± 5.4 kg) who had no injury or history of ankle sprain. Wet-ice application, cold-water immersion, or an untreated control condition applied to the ankle for 10 minutes. Muscle reaction time and muscle amplitude of the peroneus longus and tibialis anterior in response to a simulated lateral ankle sprain were calculated. The ankle-sprain simulation incorporated a combined inversion and plantar-flexion movement. We observed no change in muscle reaction time or muscle amplitude after cryotherapy for either the peroneus longus or tibialis anterior (P > .05). Ten minutes of joint cooling did not adversely affect muscle reaction time or muscle amplitude in response to a simulated lateral ankle sprain. These findings suggested that athletes can safely return to sporting activity immediately after icing. Further evidence showed that ice can be applied before ankle rehabilitation without adversely affecting dynamic neuromuscular control. Investigation in patients with acute ankle sprains is warranted to assess the clinical applicability of these interventions.

Ion distribution in the hot spot of an inertial confinement fusion plasma

Science.gov (United States)

Tang, Xianzhu; Guo, Zehua; Berk, Herb

2012-10-01

Maximizing the fusion gain of inertial confinement fusion (ICF) for inertial fusion energy (IFE) applications leads to the standard scenario of central hot spot ignition followed by propagating burn wave through the cold/dense assembled fuel. The fact that the hot spot is surrounded by cold but dense fuel layer introduces subtle plasma physics which requires a kinetic description. Here we perform Fokker-Planck calculations and kinetic PIC simulations for an ICF plasma initially in pressure balance but having large temperature gradient over a narrow transition layer. The loss of the fast ion tail from the hot spot, which is important for fusion reactivity, is quantified by Fokker-Planck models. The role of electron energy transport and the ambipolar electric field is investigated via kinetic simulations and the fluid moment models. The net effect on both hot spot ion temperature and the ion tail distribution, and hence the fusion reactivity, is elucidated.

Nuclear physics for nuclear fusion

International Nuclear Information System (INIS)

Li Xingzhong; Liu Bin; Wei Qingming; Ren Xianzhe

2004-01-01

The D-T fusion cross-section is calculated using quantum mechanics with the model of square nuclear potential well and Coulomb potential barrier. The agreement between ENDF data and the theoretically calculated results is well in the range of 0.2-280 keV. It shows that the application of Breit-Wigner formula is not suitable for the case of the light nuclei fusion reaction. When this model is applied to the nuclear reaction between the charged particles confined in a lattice, it explains the 'abnormal phenomena'. It implies a prospect of nuclear fusion energy without strong nuclear radiations

Stimulated cold fusion by positronium atoms, cross sections, and wall interactions in plasmas, used to diagnostics

International Nuclear Information System (INIS)

Emami, Z.

2005-01-01

Because of the technical complexities, involved in the controlled thermonuclear, reactions, a simple vicegerent agent cold plasma, stimulated by positronium atoms (achieved through a ring storage) as stimulus, introduced by this author in ITC 12 conference. In the present paper, the interaction between γ rays emitted through positronium atoms annihilation (in the forms of doublet and triplet electromagnetic photonic radiation) with plasma particles (including electrons, ions and neutral particles) investigated. Proper lifetime of singlet γ rays τs are about 100 ns and from that of triplet γ rays, i.e τt about 100 fems, reside in the following transition times in Ne and Argon elements in He-Ne and Ar lasers respectively: Ne*(3S2) [transition time τ = 105 ns] -> Ne*(2P4); Ar+*(3P4 4S) [transition time τ = 105 fems] -> Ar+(3P5). Then the interactions of γ rays with mater in plasma could follow up as treated from that of the laser and mater in one extreme while the comparison of this situation with normal plasmas in other extreme could serve as diagnostics key role in magnetically confined plasmas reactors. Collisions between charge and neutral species in plasma with electromagnetic radiation (γ photonic radiation) including the energy loss and scattering lead to different consequences. Light electrons can take up appreciably amounts of energy from the incident rays, lead to heating cold plasma, whereas massive ions absorb very little energy. Thus loss of incident energy in radiation occurs almost entirely in collisions with electrons , which, referred to the γ rays energy this would led to plasma heating about thermonuclear reaction ( Eγ = hν = 0.5 MeV). The heavy ions and neutral species in interaction with electromagnetic γ radiation, result on the other hand in scattering, in turn may increase the ionization level of the cold plasma, toward fully ionized plasma. Although all the essential features of these different interaction cross sections deduced

Nuclear fusion power

International Nuclear Information System (INIS)

Dinghee, D.A.

1983-01-01

In this chapter, fusion is compared with other inexhaustible energy sources. Research is currently being conducted both within and outside the USA. The current confinement principles of thermonuclear reactions are reveiwed with the discussion of economics mainly focusing on the magnetic confinement concepts. Environmental, health and safety factors are of great concern to the public and measures are being taken to address them. The magnetic fusion program logic and the inertial fusion program logic are compared

Controlled thermonuclear fusion

CERN Document Server

Bobin, Jean Louis

2014-01-01

The book is a presentation of the basic principles and main achievements in the field of nuclear fusion. It encompasses both magnetic and inertial confinements plus a few exotic mechanisms for nuclear fusion. The state-of-the-art regarding thermonuclear reactions, hot plasmas, tokamaks, laser-driven compression and future reactors is given.

Studies of heavy-ion reactions and transuranic nuclei. Progress report, September 1, 1992--August 31, 1993

Energy Technology Data Exchange (ETDEWEB)

Schroeder, W.U.

1993-08-01

This report contain papers on the following topics: The Cold-Fusion Saga; Decay Patterns of Dysprosium Nuclei Produced in {sup 32}S + {sup 118,124}Sn Fusion Reactions; Unexpected Features of Reactions Between Very Heavy Ions at Intermediate Bombarding Energies; Correlations Between Neutrons and Charged Products from the Dissipative Reaction {sup 197}Au+{sup 208}Pb at E/A = 29 MeV; Dissipative Dynamics of Projectile-Like Fragment Production in the Reaction {sup 209}Bi+{sup 136}Xe at E/A = 28.2 MeV; Dynamical Production of Intermediate-Mass Fragments in Peripheral {sup 209}Bi+{sup 136}Xe Collisions at E{sub lab}/A = 28.2 MeV; The Rochester 960-Liter Neutron Multiplicity Meter; A Simple Pulse Processing Concept for a Low-Cost Pulse-Shape-Based Particle Identification; A One-Transistor Preamplifier for PMT Anode Signals; A Five-Channel Multistop TDC/Event Handler for the SuperBall Neutron Multiplicity Meter; Construction of the SuperBall -- a 16,000-Liter Neutron Detector for Calorimetric Studies of Intermediate-Energy Heavy-Ion Reactions; A Computer Code for Light Detection Efficiency Calculations for Photo-multipliers of a Neutron Detector; Evaluation of Gd-Loaded Liquid Scintillators for the SuperBall Neutron Calorimeter; and Measurement of the Interaction of Cosmic-Ray {mu}{sup {minus}} with a Muon Telescope.

FENDL/C-1.0. Charged-particle reaction data library for fusion applications Version 1.0 of November 1991. Summary documentation

International Nuclear Information System (INIS)

Pashchenko, A.B.

1995-01-01

This document describes the FENDL/C-1.0 charged-particle reaction data library which is a sublibrary of FENDL, the evaluated nuclear data library for fusion applications. This file contains evaluated data in ENDF-6 format for the D(d,n), D(d,p), T(d,n), T(t,2n), He-3(d,p) reactions. The processed information, i.e. Maxwellian-averaged reaction rates, and related quantities, calculated from reaction cross-sections, are also included. The data are available from the Nuclear Data Section online via INTERNET by FTP command, or on magnetic tape upon request. (author). 1 tab

Dynamical limitations to heavy ion fusion

International Nuclear Information System (INIS)

Back, B.B.

1983-01-01

Dynamical limitations to heavy ion fusion reaction are considered. The experimental signatures and the importance of a quasi-fission process are examined. The anaular distributions of fission fragments for the 32 S+ 208 Pb and 16 O+ 238 U systems are presented. It is shown that the observations of quasi-fission for even rather ''light'' heavy ions poeess severe limitations on the fusion process. This result may consequently be responsible for the lack of success of the search for super heavy elements in heavy ion fusion reactions

Fusion barriers in heavy ion collisions

International Nuclear Information System (INIS)

Zhu Long; Su Jun; Xie Wenjie; Guo Chenchen; Zhang Donghong; Zhang Fengshou

2014-01-01

Study of fusion barrier is very important for people to better understand fusion reactions. In this paper the Improved Isospin-dependent Quantum Molecular Dynamics (ImIQMD) model is introduced firstly. Then the shell correction effects, energy dependence, isospin effects and orientation effects of fusion barrier are studied. The fusion barriers for the fusion reactions "4"0Ca + "4"0Ca, "4"8Ca + "2"0"8Pb, "4"8Ca + "2"0"4Pb and "1"6O + "1"5"4Sm are extracted. The negative shell correction energies lower potential barriers of a certain reaction. A complex phenomenon of energy dependence is observed. It is also found that incident energy dependence of the barrier radius and barrier height shows opposite behaviors. The Coulomb potential shows weak energy dependence when distance of two colliding nuclei is lower than the touching distance. The isospin effects of the potential barrier are investigated. The orientation effects of the potential barrier are also discussed for the system "1"6O + "1"5"4Sm. (authors)

Incomplete fusion analysis of the 7Li-induced reaction on 93Nb within 3-6.5 MeV/nucleon

Science.gov (United States)

Kumar, Deepak; Maiti, Moumita

2017-10-01

Background: It is understood from the recent experimental studies that prompt/resonant breakup, and transfer followed by breakup in the weakly bound Li,76-induced reactions play a significant role in the complete-incomplete fusion (CF-ICF), suppression/enhancement in the fusion cross section around the Coulomb barrier. Purpose: Investigation of ICF over CF by measuring cross sections of the populated residues, produced via different channels in the 7Li-induced reaction on a natNb target within the 3-6.5 MeV/nucleon energy region. Method: The 7Li beam was allowed to hit the self-supporting 93Nb targets, backed by the aluminium (Al) foil alternately, within 3-6.5 MeV/nucleon energy. Populated residues were identified by offline γ -ray spectrometry. Measured excitation functions of different channels were compared with different equilibrium and pre-equilibrium models. Result: The enhancement in cross sections in the proton (˜20 -30 MeV) and α -emitting channels, which may be ascribed to ICF, was observed in the measured energy range when compared to the Hauser-Feshbach and exciton model calculations using empire, which satisfactorily reproduces the neutron channels, compared to the Weisskopf-Ewing model and hybrid Monte Carlo calculations. The increment of the incomplete fusion fraction was observed with rising projectile energy. Conclusion: Contrary to the alice14, experimental results are well reproduced by the empire throughout the measured energy range. The signature of ICF over CF indicates that the breakup/transfer processes are involved in the weakly bound 7Li-induced reaction on 93Nb slightly above the Coulomb barrier.

Muon nuclear fusion and low temperature nuclear fusion

International Nuclear Information System (INIS)

Nagamine, Kanetada

1990-01-01

Low temperature (or normal temperature) nuclear fusion is one of the phenomena causing nuclear fusion without requiring high temperature. In thermal nuclear fusion, the Coulomb barrier is overcome with the help of thermal energy, but in the low temperature nuclear fusion, the Coulomb barrier is neutralized by the introduction of the particles having larger mass than electrons and negative charges, at this time, if two nuclei can approach to the distance of 10 -13 cm in the neutral state, the occurrence of nuclear fusion reaction is expected. As the mass of the particles is heavier, the neutral region is smaller, and nuclear fusion is easy to occur. The particles to meet this purpose are the electrons within substances and muons. The research on muon nuclear fusion became suddenly active in the latter half of 1970s, the cause of which was the discovery of the fact that the formation of muons occurs resonantly rapidly in D-T and D-D systems. Muons are the unstable elementary particles having the life of 2.2 μs, and they can have positive and negative charges. In the muon catalyzed fusion, the muons with negative charge take part. The principle of the muon catalyzed fusion, its present status and future perspective, and the present status of low temperature nuclear fusion are reported. (K.I.)

Stripping of two protons and one alpha particle transfer reactions for 16 O + A Sm and their influence on the fusion cross section

International Nuclear Information System (INIS)

Maciel, A.M.M.; Gomes, P.R.S.

1995-01-01

Transfer cross section angular distribution data for the stripping of two protons and one alpha particle are studied for the 16 O + A Sm systems (A=144, 148, 150, 152 and 154), at near barrier energies. A semiclassical formalism is used to derive the corresponding transfer form factors. For only one channel the analysis shows evidences that the transfer reaction mechanism at backward angles - corresponding to small distances, may behave as a multi-step process leading to fusion. Simplified coupled channel calculations including transfer channels are performed for the study of the sub-barrier of these systems. The influence of short distance transfer reactions on the fusion is discussed. (author)

Fusion research principles

CERN Document Server

Dolan, Thomas James

2013-01-01

Fusion Research, Volume I: Principles provides a general description of the methods and problems of fusion research. The book contains three main parts: Principles, Experiments, and Technology. The Principles part describes the conditions necessary for a fusion reaction, as well as the fundamentals of plasma confinement, heating, and diagnostics. The Experiments part details about forty plasma confinement schemes and experiments. The last part explores various engineering problems associated with reactor design, vacuum and magnet systems, materials, plasma purity, fueling, blankets, neutronics

Overview of safety and environmental issues for inertial fusion energy

International Nuclear Information System (INIS)

Piet, S.J.; Brereton, S.J.; Tanaka, S.

1996-01-01

This paper summarizes safety and environmental issues of Inertial Fusion Energy (IFE): inventories, effluents, maintenance, accident safety, waste management, and recycling. The fusion confinement approach among inertial and magnetic options affects how the fusion reaction is maintained and which materials surround the reaction chamber. The target fill technology has a major impact on the target factory tritium inventory. IFE fusion reaction chambers usually employ some means to protect the first structural wall from fusion pulses. This protective fluid or granular bed also moderates and absorbs most neutrons before they reach the first structural wall. Although the protective fluid activates, most candidate fluids have low activation hazard. Hands-on maintenance seems practical for the driver, target factory, and secondary coolant systems; remote maintenance is likely required for the reaction chamber, primary coolant, and vacuum exhaust cleanup systems. The driver and fuel target facility are well separated from the main reaction chamber

The fusion-fission hybrid

International Nuclear Information System (INIS)

Teller, E.

1985-01-01

As the history of the development of fusion energy shows, a sustained controlled fusion reaction is much more difficult to produce than rapid uncontrolled release of fusion energy. Currently, the ''magnetic bottle'' technique shows sufficient progress that it might applied for the commercial fuel production of /sup 233/U, suitable for use in fission reactors, by developing a fusion-fission hybrid. Such a device would consist of a fusion chamber core surrounded by a region containing cladded uranium pellets cooled by helium, with lithium salts also present to produce tritium to refuel the fusion process. Successful development of this hybrid might be possible within 10 y, and would provide both experience and funds for further development of controlled fusion energy

Heavy cluster in cold nuclear rearrangements in fusion and fission

International Nuclear Information System (INIS)

Armbruster, P.

1997-01-01

The experimental evidence for the appearance of cluster aspects in the dynamics of large rearrangements processes, as fusion and fission, is presented. Clusters in the sense as used in the following are strongly bound, doubly magic neutron rich nuclei as 48 Ca 28 , 78 Ni 50 , 132 Sn 82 , and 208 Pb 126 , the spherical nuclei Z=114 - 126 and N=184, and nuclei with closed shells N=28, 50, 82, and 126, and Z=28, 50, and 82. As with increasing nucleon numbers, the absolute shell corrections to the binding energies increase, the strongest effects are to be observed for the higher shells. The 132 cluster manifests itself in low energy fission (Faissner, H. and Wildermuth, K. Nucl. Phys., 58 (1964) 177). The 208 Pb cluster gave the new radioactivity (Rose, M.J. and Jones G.A., Nature, 307 (1984) 245) and the first superheavy elements (SHE) (Armbruster P., Ann. Rev. Nucl. Part. Sci., 35 (1985) 135-94; Munzenberg, G. Rep. Progr. Phys., 51 (1988) 57). The paper discuss experiments concerning the stability of clusters to intrinsic excitation energy in fusion and fission (Armbruster, P. Lect. Notes Phys., 158 (1982) 1). and the manifestation of clusters in the fusion entrance channel (Armbruster, P., J. Phys. Soc. Jpn., 58 (1989) 232). The importance of compactness of the clustering system seems to be equally decisive in fission and fusion. Finally, it s covered the importance of clusters for the production of SHEs)

Nuclear reactions and the synthesis of new species

International Nuclear Information System (INIS)

Anon.

1983-01-01

Targets of relatively short-lived, neutron-rich transplutonium isotopes, such as 254 Es, which are produced by the HFIR/TRU, when combined with the capabilities of modern heavy-ion accelerators, offer a unique possibility to expand our knowledge of chemical elements and atomic nuclei toward the limits of nuclear stability. This knowledge should enable us to delineate the forces that eventually terminate the periodic table at its upper end. Specifically, the panel concludes that significant research opportunities exist in several areas, which are highlighted below: Nucleon-transfer reactions between light heavy-ion projectiles (such as 18 O, 22 Ne, or 48 Ca) and 254 Es targets will give access to a completely uncharted region of neutron-rich isotopes. Cold-fusion reactions of 48 Ca projectiles with /sup 254,255/Es targets should yield superheavy nuclei with neutron numbers very close to the predicted closed neutron shell at N = 184

Fusion - 2050 perspective (in Polish)

CERN Document Server

Romaniuk, R S

2013-01-01

The results of strongly exothermic reaction of thermonuclear fusion between nuclei of deuterium and tritium are: helium nuclei and neutrons, plus considerable kinetic energy of neutrons of over 14 MeV. DT nuclides synthesis reaction is probably not the most favorable one for energy production, but is the most advanced technologically. More efficient would be possibly aneutronic fusion. The EU by its EURATOM agenda prepared a Road Map for research and implementation of Fusion as a commercial method of thermonuclear energy generation in the time horizon of 2050.The milestones on this road are tokomak experiments JET, ITER and DEMO, and neutron experiment IFMIF. There is a hope, that by engagement of the national government, and all research and technical fusion communities, part of this Road Map may be realized in Poland. The infrastructure build for fusion experiments may be also used for material engineering research, chemistry, biomedical, associated with environment protection, power engineering, security, ...

Dynamical Dipole and Equation of State in N/Z Asymmetric Fusion Reactions

Directory of Open Access Journals (Sweden)

Giaz Agnese

2014-03-01

Full Text Available In heavy ion reactions, in the case of N/Z asymmetry between projectile and target, the process leading to complete fusion is expected to produce pre-equilibrium dipole γ-ray emission. It is generated during the charge equilibration process and it is known as Dynamical Dipole. A new measurement of the dynamical dipole emission was performed by studying 16O + 116Sn at 12 MeV/u. These data, together with those measured at 8.1 MeV/u and 15.6 MeV/u for the same reaction, provide the dependence on the Dynamical Dipole total emission yield with beam energy and they can be compared with theoretical expectations. The experimental results show a weak increase of the Dynamical Dipole total yield with beam energies and are in agreement with the prediction of a theoretical model based on the Boltzmann–Nordheim–Vlasov (BNV approach. The measured trend with beam energy does not confirm the rise and fall behavior previously reported for the same fused compound but with a much higher dipole moment.

Consistent analysis of peripheral reaction channels and fusion for the 16,18O+58Ni systems

International Nuclear Information System (INIS)

Alves, J.J.S.; Gomes, P.R.S.; Lubian, J.; Chamon, L.C.; Pereira, D.; Anjos, R.M.; Rossi, E.S.; Silva, C.P.; Alvarez, M.A.G.; Nobre, G.P.A.; Gasques, L.R.

2005-01-01

We have measured elastic scattering and peripheral reaction channel cross sections for the 16,18 O+ 58 Ni systems at ELab=46 MeV. The data were analyzed through extensive coupled-channel calculations. It was investigated the consistency of the present analysis with a previous one at sub-barrier energies. Experimental fusion cross sections for these systems are also compared with the corresponding predictions of the coupled-channel calculations

Analytical criterion for shock ignition of fusion reaction in hot spot

International Nuclear Information System (INIS)

Ribeyre, X.; Tikhonchuk, V. T.; Breil, J.; Lafon, M.; Vallet, A.; Bel, E. L.

2013-01-01

Shock ignition of DT capsules involves two major steps. First, the fuel is assembled by means of a low velocity conventional implosion. At stagnation, the central core has a temperature lower than the one needed for ignition. Then a second, strong spherical converging shock, launched from a high intensity laser spike, arrives to the core. This shock crosses the core, rebounds at the target center and increases the central pressure to the ignition conditions. In this work we consider this latter phase by using the Guderley self-similar solution for converging flows. Our model accounts for the fusion reaction energy deposition, thermal and radiation losses thus describing the basic physics of hot spot ignition. The ignition criterion derived from the analytical model is successfully compared with full scale hydrodynamic simulations. (authors)

Advanced fusion reactor

International Nuclear Information System (INIS)

Tomita, Yukihiro

2003-01-01

The main subjects on fusion research are now on D-T fueled fusion, mainly due to its high fusion reaction rate. However, many issues are still remained on the wall loading by the 14 MeV neutrons. In the case of D-D fueled fusion, the neutron wall loading is still remained, though the technology related to tritium breeding is not needed. The p- 6 Li and p- 11 B fueled fusions are not estimated to be the next generation candidate until the innovated plasma confinement technologies come in useful to achieve the high performance plasma parameters. The fusion reactor of D- 3 He fuels has merits on the smaller neutron wall loading and tritium handling. However, there are difficulties on achieving the high temperature plasma more than 100 keV. Furthermore the high beta plasma is needed to decrease synchrotron radiation loss. In addition, the efficiency of the direct energy conversion from protons coming out from fusion reaction is one of the key parameters in keeping overall power balance. Therefore, open magnetic filed lines should surround the plasma column. In this paper, we outlined the design of the commercial base reactor (ARTEMIS) of 1 GW electric output power configured by D- 3 He fueled FRC (Field Reversed Configuration). The ARTEMIS needs 64 kg of 3 He per a year. On the other hand, 1 million tons of 3 He is estimated to be in the moon. The 3 He of about 10 23 kg are to exist in gaseous planets such as Jupiter and Saturn. (Y. Tanaka)

Muon catalyzed fusion under compressive conditions

International Nuclear Information System (INIS)

Cripps, G.; Goel, B.; Harms, A.A.

1991-01-01

The viability of a symbiotic combination of Muon Catalyzed Fusion (μCF) and high density generation processes has been investigated. The muon catalyzed fusion reaction rates are formulated in the temperature and density range found under moderate compressive conditions. Simplified energy gain and power balance calculations indicate that significant energy gain occurs only if standard type deuterium-tritium (dt) fusion is ignited. A computer simulation of the hydrodynamics and fusion kinetics of a spherical deuterium-tritium pellet implosion including muons is performed. Using the muon catalyzed fusion reaction rates formulated and under ideal conditions, the pellet ignites (and thus has a significant energy gain) only if the initial muon concentration is approximately 10 17 cm -3 . The muons need to be delivered to the pellet within a very short-time (≅ 1 ns). The muon pulse required in order to make the high density and temperature muon catalyzed fusion scheme viable is beyond the present technology for muon production. (orig.) [de

Low-Energy Nuclear Reactions Resulting as Picometer Interactions with Similarity to K-Shell Electron Capture

Science.gov (United States)

Hora, H.; Miley, G. H.; Li, X. Z.; Kelly, J. C.; Osman, F.

2006-02-01

Since the appeal by Brian Josephson at the meeting of the Nobel Laureates July 2004, it seems to be indicated to summarize the following serious, reproducible and confirmed observations on reactions of protons or deuterons incorporated in host metals such as palladium. Some reflections to Rutherford's discovery of nuclear physics, the Cockroft-Oliphant discovery of anomalous low-energy fusion reactions and the chemist Hahn's discovery of fission had to be included. Using gaseous atmosphere or discharges between palladium targets, rather significant results were seen e.g. from the "life after death" heat production of such high values per host atom that only nuclear reactions can be involved. This supports the earlier evaluation of neutron generation in fully reversible experiments with gas discharges hinting that a reasonable screening effect - preferably in the swimming electron layer - may lead to reactions at nuclear distances d of picometers with reaction probability times U of about megaseconds similar to the K-shell capture radioactivity. Further electrolytic experiments led to low-energy nuclear reactions (LENR) where the involvement of pollution could be excluded from the appearance of very seldom rare earth elements. A basically new theory for DD cross-sections is used to confirm the picometer-megasecond reactions of cold fusion. Other theoretical aspects are given from measured heavy element distributions similar to the standard abundance distribution, SAD, in the Universe with consequences on endothermic heavy nuclei generation, magic numbers and to quark-gluon plasmas.

Low-energy nuclear reactions resulting as parametric interactions with similarity to K-shell electron capture

International Nuclear Information System (INIS)

Hora, H.; Miley, G.H.; Li, X.Z.; Kelly, J.C.; Osman, F.

2006-01-01

Since the appeal by Brian Josephson at the meeting of the Nobel Laureates July 2004, it seems to be indicated to summarize the following serious, reproducible and confirmed observations on reactions of protons of deuterons incorporated in host metals such as palladium. Some reflections to Rutherford's discovery of nuclear physics, the Cockcroft Oliphant discovery of anomalous low-energy fusion reactions and the chemist Hahn's discovery of fission had to be included. Using gaseous atmosphere or discharges between palladium targets, rather significant results were seen e.g. from the 'life after death' heat production of such high values per host atom that only nuclear reactions can be involved. This supports the earlier evaluation of neutron generation in fully reversible experiments with gas discharges hinting that a reasonable screening effect - preferably in the swimming electron layer - may lead to reactions at nuclear distances d of pico-meters with reaction probability times U of about mega-seconds similar to the K-shell capture radioactivity. Further electrolytic experiments led to low-energy nuclear reactions (LENR) where the involvement of pollution could be excluded from the appearance of very seldom rare earth elements. A basically new theory for DD cross-sections is used to confirm the pico-meter- mega-second reactions of cold fusion. Other theoretical aspects are given from measured heavy element distributions similar to the standard abundance distribution, SAD, in the Universe with consequences on endothermic heavy nuclei generation, magic numbers and to quark-gluon plasmas. (authors)

Production of neutron-rich isotopes by cold fragmentation in the reaction 197Au + Be at 950 A MeV

International Nuclear Information System (INIS)

Benlliure, J.; Pereira, J.; Schmidt, K.H.; Cortina-Gil, D.; Enqvist, T.; Heinz, A.; Junghans, A.R.; Farget, F.; Taieb, J.

1999-09-01

The production cross sections and longitudinal-momentum distributions of very neutron-rich isotopes have been investigated in the fragmentation of a 950 A MeV 179 Au beam in a beryllium target. Seven new isotopes ( 193 Re, 194 Re, 191 W, 192 W, 189 Ta, 187 Hf and 188 Hf) and the five-proton-removal channel were observed for the first time. The reaction mechanism leading to the formation of these very neutron-rich isotopes is explained in terms of the cold-fragmentation process. An analytical model describing this reaction mechanism is presented. (orig.)

Electron-impact excitation and recombination of molecular cations in edge fusion plasma: application to H2+and BeD+

Science.gov (United States)

Pop, Nicolina; Iacob, Felix; Mezei, Zsolt; Motapon, Ousmanou; Niyonzima, Sebastien; Schneider, Ioan

2017-10-01

Dissociative recombination, ro-vibrational excitation and dissociative excitation of molecular cations with electrons are major elementary process in the kinetics and in the energy balance of astrophysically-relevant ionized media (supernovae, interstellar molecular clouds, planetary ionospheres, early Universe), in edge fusion and in many other cold media of technological interest. For the fusion plasma edge, extensive cross sections and rate coefficients have been produced for reactions induced on HD+, H2+ and BeD+ using the Multichannel Quantum Defect Theory (MQDT). Our calculations resulted in good agreement with the CRYRING (Stockholm) and TSR (Heidelberg) magnetic storage ring results, and our approach is permanently improved in order to face the new generation of electrostatic storage rings, as CSR (Heidelberg) and DESIREE (Stockholm). Member of APS Reciprocal Society: European Physics Society.

Atomic data for fusion

Energy Technology Data Exchange (ETDEWEB)

Hunter, H.T.; Kirkpatrick, M.I.; Alvarez, I.; Cisneros, C.; Phaneuf, R.A. (eds.); Barnett, C.F.

1990-07-01

This report provides a handbook of recommended cross-section and rate-coefficient data for inelastic collisions between hydrogen, helium and lithium atoms, molecules and ions, and encompasses more than 400 different reactions of primary interest in fusion research. Published experimental and theoretical data have been collected and evaluated, and the recommended data are presented in tabular, graphical and parametrized form. Processes include excitation and spectral line emission, charge exchange, ionization, stripping, dissociation and particle interchange reactions. The range of collision energies is appropriate to applications in fusion-energy research.

Atomic data for fusion

International Nuclear Information System (INIS)

Hunter, H.T.; Kirkpatrick, M.I.; Alvarez, I.; Cisneros, C.; Phaneuf, R.A.; Barnett, C.F.

1990-07-01

This report provides a handbook of recommended cross-section and rate-coefficient data for inelastic collisions between hydrogen, helium and lithium atoms, molecules and ions, and encompasses more than 400 different reactions of primary interest in fusion research. Published experimental and theoretical data have been collected and evaluated, and the recommended data are presented in tabular, graphical and parametrized form. Processes include excitation and spectral line emission, charge exchange, ionization, stripping, dissociation and particle interchange reactions. The range of collision energies is appropriate to applications in fusion-energy research

Use of high current density superconducting coils in fusion devices

International Nuclear Information System (INIS)

Green, M.A.

1979-11-01

Superconducting magnets will play an important role in fusion research in years to come. The magnets which are currently proposed for fusion research use the concept of cryostability to insure stable operation of the superconducting coils. This paper proposes the use of adiabatically stable high current density superconducting coils in some types of fusion devices. The advantages of this approach are much lower system cold mass, enhanced cryogenic safety, increased access to the plasma and lower cost

Concepts for fusion fuel production blankets

International Nuclear Information System (INIS)

Gierszewski, P.

1986-06-01

The fusion blanket surrounds the burning hydrogen core of the fusion reactor. It is in this blanket that most of the energy released by the DT fusion reaction is converted into useable product, and where tritium fuel is produced to enable further operation of the reactor. Blankets will involve new materials, conditions and processes. Several recent fusion blanket concepts are presented to illustrate the range of ideas

Development of Portable Pulsed Neutron Generators Utilizing a D-T or D-D Fusion Reaction

International Nuclear Information System (INIS)

Nishimura, Kazuya; Miake, Yoshinobu; Kato, Michio; Rintsu, Yukou

2001-01-01

Prototypes of sealed neutron tubes in a D-T or D-D fusion reaction for logging while drilling (LWD) were developed; then operational tests were performed to check their functional properties. One of the prototypes passed most of the specified conditions for using LWD. Further studies were needed to put a sealed neutron tube into practical use. For applications to other fields, such as an in situ calibration source for neutron detector efficiencies and an in situ calibration source for fusion systems, a sealed neutron tube is needed to have higher-intensity neutron output and a long life. Thus, the performance of the ion source used in the neutron tube is improved to obtain high gas utilization efficiencies or low-pressure operation with high ionization efficiencies. The characteristics of the new ion sources used in the foregoing sealed neutron tube are discussed in terms of preliminary tests. The aforementioned performances are obtained

Breeder control fusion reactor. Topical interview

Energy Technology Data Exchange (ETDEWEB)

Schlueter, A [Max-Planck-Institut fuer Plasmaphysik, Garching/Muenchen (Germany, F.R.)

1977-09-01

The energy sources of the future are extremely controversial. The consumption of fossil fuel shall decrease during the next decades, because exhaustion of the resources, pollution, increase of CO/sub 2/ in the atmosphere and other reasons. But at present the question it not yet settled which alternative energy system should replace the fossil fuel. First of all nuclear energy in the form of fission reactions seems to come into operation to a larger extent. The next step may be the controlled thermonuclear fusion reaction. Furthermore, a comparison between fusion and fission is given which shows that fusion would bring about less risks than the breeders. An advantage of the fusion reactor would be the fact that the fuel cycle is closed. Unfortunately, the physical questions are not as yet satisfactorily clarified so that one cannot be sure whether a fusion reactor can really be built.

Comparison of different Skyrme forces: Fusion barriers and fusion cross sections

International Nuclear Information System (INIS)

Puri, R.K.; Gupta, R.K.

1995-01-01

Fusion barriers and fusion cross sections are calculated using the Skyrme energy-density formalism. To study the role of different parametrizations of the Skyrme interaction, we use two typical forces, i.e., the original Skyrme force S and the widely used Skyrme force SIII. Our calculations show that, in the reactions considered here, the Skyrme force S gives higher fusion cross sections compared to that of the Skyrme force SIII. The main part of this difference can be associated with the presence of the spin-density contribution in the Skyrme force SIII

Coatings for fusion reactor environments

International Nuclear Information System (INIS)

Mattox, D.M.

1979-01-01

The internal surfaces of a tokamak fusion reactor control the impurity injection and gas recycling into the fusion plasma. Coating of internal surfaces may provide a desirable and possibly necessary design flexibility for achieving the temperatures, ion densities and containment times necessary for net energy production from fusion reactions to take place. In this paper the reactor environments seen by various componentare reviewed along with possible materials responses. Characteristics of coating-substrate systems, important to fusion applications, are delineated and the present status of coating development for fusion applications is reviewed. Coating development for fusion applications is just beginning and poses a unique and important challenge for materials development

Advanced fusion reactor

Energy Technology Data Exchange (ETDEWEB)

Tomita, Yukihiro [National Inst. for Fusion Science, Toki, Gifu (Japan)

2003-04-01

The main subjects on fusion research are now on D-T fueled fusion, mainly due to its high fusion reaction rate. However, many issues are still remained on the wall loading by the 14 MeV neutrons. In the case of D-D fueled fusion, the neutron wall loading is still remained, though the technology related to tritium breeding is not needed. The p-{sup 6}Li and p-{sup 11}B fueled fusions are not estimated to be the next generation candidate until the innovated plasma confinement technologies come in useful to achieve the high performance plasma parameters. The fusion reactor of D-{sup 3}He fuels has merits on the smaller neutron wall loading and tritium handling. However, there are difficulties on achieving the high temperature plasma more than 100 keV. Furthermore the high beta plasma is needed to decrease synchrotron radiation loss. In addition, the efficiency of the direct energy conversion from protons coming out from fusion reaction is one of the key parameters in keeping overall power balance. Therefore, open magnetic filed lines should surround the plasma column. In this paper, we outlined the design of the commercial base reactor (ARTEMIS) of 1 GW electric output power configured by D-{sup 3}He fueled FRC (Field Reversed Configuration). The ARTEMIS needs 64 kg of {sup 3}He per a year. On the other hand, 1 million tons of {sup 3}He is estimated to be in the moon. The {sup 3}He of about 10{sup 23} kg are to exist in gaseous planets such as Jupiter and Saturn. (Y. Tanaka)

Workshop on cold-blanket research

International Nuclear Information System (INIS)

1977-05-01

The objective of the workshop was to identify and discuss cold-plasma blanket systems. In order to minimize the bombardment of the walls by hot neutrals the plasma should be impermeable. This requires a density edge-thickness product of nΔ > 10 15 cm -2 . An impermeable cold plasma-gas blanket surrounding a hot plasma core reduces the plasma wall/limiter interaction. Accumulation of impurities in this blanket can be expected. Fuelling from a blanket may be possible as shown by experimental results, though not fully explained by classical transport of neutrals. Refuelling of a reacting plasma had to be ensured by inward diffusion. Experimental studies of a cold impermeable plasma have been done on the tokamak-like Ringboog device. Simulation calculations for the next generation of large tokamaks using a particular transport model, indicate that the plasma edge profile can be controlled to reduce the production of sputtered impurities to an acceptable level. Impurity control requires a small fraction of the radial space to accomodate the cold-plasma layer. The problem of exhaust is, however, more complicated. If the cold-blanket scheme works as predicted in the model calculations, then α-particles generated by fusion will be transported to the cold outside layer. The Communities' experimental programme of research has been discussed in terms of the tokamaks which are available and planned. Two options present themselves for the continuation of cold-blanket research

Accountability in Science During the Information Era: Lessons Drawn from the "Cold Fusion Furor"

Science.gov (United States)

Chubb, Scott

2001-04-01

As guest editor of a recent Ethics in Science publication(S. R. Chubb, Accountability in Research, v 8), #'s 1 and 2, 1 (2000). journals/149/149-top.htm>(http://www.gbhap us.com/journals/149/149-top.htm), I requested key players, from both sides of the Cold Fusion (CF) debate, to attempt to go beyond questions involving the merits of CF, by addressing a more basic issue: have CF claims been judged effectively. All participants agreed that this has not occurred. Three factors seem to have been responsible: 1. Errors in the initial neutron measurements, 2. Events immediately prior to and during a specific APS session, held 1 May 1989, and 3. Irresponsible use of FAX machines and the Internet. The resulting furor, fueled by these Information Era Technologies (IET's), has evolved into such a serious breakdown in communication that, even after 11 years, it is impossible to rule-out the possibility that a number of important new discoveries may have occurred. Regardless of the merits of the claims, two lessons can be drawn from the debate: 1. Individuals and groups must be held accountable for their actions and statements, 2. When IET users fail to respect each other, IET's can seriously impede communication.

Cold urticaria: inhibition of cold-induced histamine release by doxantrazole.

Science.gov (United States)

Bentley-Phillips, C B; Eady, R A; Greaves, M W

1978-10-01

Thirteen patients with cold urticaria were studied to assess the effect of the systemic drug doxantrazole, which has actions resembling disodium cromoglycate, on cold evoked histamine release. The patients, all of whom developed an immediate local whealing response after cooling of the forearm, demonstrated release of histamine into venous blood draining that forearm. Following doxantrazole treatment, significant suppression of histamine release occurred. In some but not all patients this was accompanied by diminution of urtication in response to cooling. A double-blind study was carried out in 3 subjects, all of whom showed diminished cold-stimulated histamine release after doxantrazole. Two of these showed clinical improvement. Doxantrazole had no effect on erythema due to intradermal histamine, but did suppress the erythematous reaction to intradermal injection of compound 48/80. Our results suggest that doxantrazole or related anti-allergic agents might be useful in the treatment of cold urticaria.

Nuclear fusion

International Nuclear Information System (INIS)

Huber, H.

1978-01-01

A comprehensive survey is presented of the present state of knowledge in nuclear fusion research. In the first part, potential thermonuclear reactions, basic energy balances of the plasma (Lawson criterion), and the main criteria to be observed in the selection of appropriate thermonuclear reactions are dealt with. This is followed by a discussion of the problems encountered in plasma physics (plasma confinement and heating, transport processes, plasma impurities, plasma instabilities and plasma diagnostics) and by a consideration of the materials problems involved, such as material of the first wall, fuel inlet and outlet, magnetic field generation, as well as repair work and in-service inspections. Two main methods have been developed to tackle these problems: reactor concepts using the magnetic pinch (stellarator, Tokamak, High-Beta reactors, mirror machines) on the one hand, and the other concept using the inertial confinement (laser fusion reactor). These two approaches and their specific problems as well as past, present and future fusion experiments are treated in detail. The last part of the work is devoted to safety and environmental aspects of the potential thermonuclear aspects of the potential thermonuclear reactor, discussing such problems as fusion-specific hazards, normal operation and potential hazards, reactor incidents, environmental pollution by thermal effluents, radiological pollution, radioactive wastes and their disposal, and siting problems. (orig./GG) [de

Studies of heavy-ion reactions and transuranic nuclei

International Nuclear Information System (INIS)

Schroeder, W.U.; Huizenga, J.R.

1991-08-01

The development of the ''cold-fusion'' episode is reviewed. Ongoing studies of compound-nucleus formation and decay via the neutron multiplicity distribution confirm the validity of conventional statistical theory. The excitation energy partition in near-barrier damped 58 Ni + 208 Pb collisions is found to be largely independent of the direction of net mass transfer, supporting a diffusion-like nucleon-exchange mechanism. Exclusive experiments on the heavy reaction systems 197 Au + 208 Pb and 209 Bi + 136 Xe in the Fermi-energy domain have revealed important new insights into the reaction mechanism, which is found to be dominated by damped, binary processes. The effectiveness of the neutron multiplicity as an impact-parameter filter is demonstrated. It is shown that very-heavy-ion reactions lead to transient nuclear systems with temperatures in excess of τ = 6 MeV and transfer of large, aligned spins to reaction fragments. The first measurements of neutrons in coincidence with kinematically identified reaction fragments provide evidence for the binary, sequential character of dissipative collisions in the Fermi-energy domain. Also for the first time, a full event characterization was achieved for nuclear reactions in terms of neutrons and charged particles. Technical information on this experiment is provided. First results yield strong evidence for dominantly binary primary reaction dynamics of even highly dissipative 209 Bi + (28MeV/u) 136 Xe collisions, associated with several intermediate-mass fragments

Ch. 37, Inertial Fusion Energy Technology

International Nuclear Information System (INIS)

Moses, E.

2010-01-01

Nuclear fission, nuclear fusion, and renewable energy (including biofuels) are the only energy sources capable of satisfying the Earth's need for power for the next century and beyond without the negative environmental impacts of fossil fuels. Substantially increasing the use of nuclear fission and renewable energy now could help reduce dependency on fossil fuels, but nuclear fusion has the potential of becoming the ultimate base-load energy source. Fusion is an attractive fuel source because it is virtually inexhaustible, widely available, and lacks proliferation concerns. It also has a greatly reduced waste impact, and no danger of runaway reactions or meltdowns. The substantial environmental, commercial, and security benefits of fusion continue to motivate the research needed to make fusion power a reality. Replicating the fusion reactions that power the sun and stars to meet Earth's energy needs has been a long-sought scientific and engineering challenge. In fact, this technological challenge is arguably the most difficult ever undertaken. Even after roughly 60 years of worldwide research, much more remains to be learned. the magnitude of the task has caused some to declare that fusion is 20 years away, and always will be. This glib criticism ignores the enormous progress that has occurred during those decades, progress inboth scientific understanding and essential technologies that has enabled experiments producing significant amounts of fusion energy. For example, more than 15 megawatts of fusion power was produced in a pulse of about half a second. Practical fusion power plants will need to produce higher powers averaged over much longer periods of time. In addition, the most efficient experiments to date have required using about 50% more energy than the resulting fusion reaction generated. That is, there was no net energy gain, which is essential if fusion energy is to be a viable source of electricity. The simplest fusion fuels, the heavy isotopes of

Fusion as a source of synthetic fuels

International Nuclear Information System (INIS)

Powell, J.R.; Fillo, J.A.; Steinberg, M.

1981-01-01

In the near-term, coal derived synthetic fuels will be used; but in the long-term, resource depletion and environmental effects will mandate synthetic fuels from inexhaustible sources - fission, fusion, and solar. Of the three sources, fusion appears uniquely suited for the efficient production of hydrogen-based fuels, due to its ability to directly generate very high process temperatures (up to approx. 2000 0 C) for water splitting reactions. Fusion-based water splitting reactions include high temperature electrolysis (HTE) of steam, thermochemical cycles, hybrid electrochemical/thermochemical, and direct thermal decomposition. HTE appears to be the simplest and most efficient process with efficiencies of 50 to 70% (fusion to hydrogen chemical energy), depending on process conditions

Intense fusion neutron sources

International Nuclear Information System (INIS)

Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

2010-01-01

The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 10 15 -10 21 neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 10 20 neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the neutron itself.

Intense fusion neutron sources

Science.gov (United States)

Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

2010-04-01

The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 1015-1021 neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 1020 neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the neutron itself.

Study of fusion cross-sections of 16O + 208Pb and 28Si + 208Pb reactions by effective soft-core nucleon-nucleon interaction

International Nuclear Information System (INIS)

Ghodsi, O. N.; Mahmodi, M.; Ariai, J.; O. N. Ghodsi)

2007-01-01

In this paper, the cross-sections of fusion reactions 16 O + 208 Pb, 28 Si + 208 Pb, 40 C + 40 Ca, 40 Ca + 48 Ca, 58 Ni + 58 Ni, and 16 O + 154 Sm at bombarding energies above and near the fusion barrier have been investigated. The fusion cross-sections have been studied by means of the Monte Carlo method and effective soft-core nucleon-nucleon interaction. One adjustable parameter was used in these calculations. This parameter can change the strength and repulsive parts of soft-core potential values. It has to be adjusted, so that the analytical results are in acceptable agreement with the experimental data. In our calculations, we have taken the range of the nucleon-nucleon soft-core interaction to be constant and equal to that of the M3Y-Raid potential. Results show that the higher values for the diffusion parameter in the Woods-Saxon potential obtained from a careful analysis of 16 O + 208 Pb and 28 Si + 208 Pb reactions are due to the many particle effects on the nucleon-nucleon potential. (author)

Study of fusion cross-sections of 16O + 208Pb and 28Si + 208Pb reactions by effective soft-core nucleon-nucleon interaction

Directory of Open Access Journals (Sweden)

Ghodsi Omid N.

2007-01-01

Full Text Available In this paper, the cross-sections of fusion reactions 16O + 208Pb, 28Si + 208Pb, 40C + + 40Ca, 40Ca + 48Ca, 58Ni + 58Ni, and 16O + 154Sm at bombarding energies above and near the fusion barrier have been investigated. The fusion cross-sections have been studied by means of the Monte Carlo method and effective soft-core nucleon-nucleon interaction. One adjustable parameter was used in these calculations. This parameter can change the strength and repulsive parts of soft-core potential values. It has to be adjusted, so that the analytical results are in acceptable agreement with the experimental data. In our calculations, we have taken the range of the nucleon-nucleon soft-core interaction to be constant and equal to that of the M3Y-Raid potential. Results show that the higher values for the diffusion parameter in the Woods-Saxon potential obtained from a careful analysis of 16O + 208Pb and 28Si + 208Pb reactions are due to the many particle effects on the nucleon-nucleon potential.

Laser-induced nuclear fusion

International Nuclear Information System (INIS)

Jablon, Claude

1977-01-01

Research programs on laser-induced thermonuclear fusion in the United States, in Europe and in USSR are reviewed. The principle of the fusion reactions induced is explained, together with the theoretical effects of the following phenomena: power and type of laser beams, shape and size of the solid target, shock waves, and laser-hydrodynamics coupling problems [fr

Elastic scattering, fusion, and breakup of light exotic nuclei

Energy Technology Data Exchange (ETDEWEB)

Kolata, J.J. [University of Notre Dame, Physics Department, Notre Dame, IN (United States); Guimaraes, V. [Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo, SP (Brazil); Aguilera, E.F. [Instituto Nacional de Investigaciones Nucleares, Departamento de Aceleradores, Mexico, Distrito Federal (Mexico)

2016-05-15

The present status of fusion reactions involving light (A< 20) radioactive projectiles at energies around the Coulomb barrier (E<10 MeV per nucleon) is reviewed, emphasizing measurements made within the last decade. Data on elastic scattering (providing total reaction cross section information) and breakup channels for the involved systems, demonstrating the relationship between these and the fusion channel, are also reviewed. Similarities and differences in the behavior of fusion and total reaction cross section data concerning halo nuclei, weakly-bound but less exotic projectiles, and strongly-bound systems are discussed. One difference in the behavior of fusion excitation functions near the Coulomb barrier seems to emerge between neutron-halo and proton-halo systems. The role of charge has been investigated by comparing the fusion excitation functions, properly scaled, for different neutron- and proton-rich systems. Possible physical explanations for the observed differences are also reviewed. (orig.)

Direct conversion of fusion energy

International Nuclear Information System (INIS)

Johansson, Markus

2003-03-01

Deuterium and tritium are expected to be used as fuel in the first fusion reactors. Energy is released as kinetic energy of ions and neutrons, when deuterium reacts with tritium. One way to convert the kinetic energy to electrical energy, is to let the ions and neutrons hit the reactor wall and convert the heat that is caused by the particle bombardment to electrical energy with ordinary thermal conversion. If the kinetic energy of the ions instead is converted directly to electrical energy, a higher efficiency of the energy conversion is possible. The majority of the fusion energy is released as kinetic energy of neutrons, when deuterium reacts with tritium. Fusion reactions such as the D-D reactions, the D- 3 He reaction and the p- 11 B reaction, where a larger part of the fusion energy becomes kinetic energy of charged particles, appears therefore more suitable for direct conversion. Since they have lower reactivity than the D-T reaction, they need a larger βB 2 0 to give sufficiently high fusion power density. Because of this, the fusion configurations spherical torus (ST) and field-reversed configuration (FRC), where high β values are possible, appear interesting. Rosenbluth and Hinton come to the conclusion that efficient direct conversion isn't possible in closed field line systems and that open geometries, which facilitate direct conversion, provide inadequate confinement for D- 3 He. It is confirmed in this study that it doesn't seem possible to achieve as high direct conversion efficiency in closed systems as in open systems. ST and FRC fusion power plants that utilize direct conversion seem however interesting. Calculations with the help of Maple indicate that the reactor parameters needed for a D-D ST and a D 3 He ST hopefully are possible to achieve. The best energy conversion option for a D-D or D 3 He ST appears to be direct electrodynamic conversion (DEC) together with ordinary thermal conversion or liquid metal MHD conversion (LMMHD). For a D

Direct conversion of fusion energy

Energy Technology Data Exchange (ETDEWEB)

Johansson, Markus

2003-03-01

Deuterium and tritium are expected to be used as fuel in the first fusion reactors. Energy is released as kinetic energy of ions and neutrons, when deuterium reacts with tritium. One way to convert the kinetic energy to electrical energy, is to let the ions and neutrons hit the reactor wall and convert the heat that is caused by the particle bombardment to electrical energy with ordinary thermal conversion. If the kinetic energy of the ions instead is converted directly to electrical energy, a higher efficiency of the energy conversion is possible. The majority of the fusion energy is released as kinetic energy of neutrons, when deuterium reacts with tritium. Fusion reactions such as the D-D reactions, the D-{sup 3}He reaction and the p-{sup 11}B reaction, where a larger part of the fusion energy becomes kinetic energy of charged particles, appears therefore more suitable for direct conversion. Since they have lower reactivity than the D-T reaction, they need a larger {beta}B{sup 2}{sub 0} to give sufficiently high fusion power density. Because of this, the fusion configurations spherical torus (ST) and field-reversed configuration (FRC), where high {beta} values are possible, appear interesting. Rosenbluth and Hinton come to the conclusion that efficient direct conversion isn't possible in closed field line systems and that open geometries, which facilitate direct conversion, provide inadequate confinement for D-{sup 3}He. It is confirmed in this study that it doesn't seem possible to achieve as high direct conversion efficiency in closed systems as in open systems. ST and FRC fusion power plants that utilize direct conversion seem however interesting. Calculations with the help of Maple indicate that the reactor parameters needed for a D-D ST and a D{sub 3} He ST hopefully are possible to achieve. The best energy conversion option for a D-D or D{sub 3} He ST appears to be direct electrodynamic conversion (DEC) together with ordinary thermal conversion

Decomposition of incomplete fusion

International Nuclear Information System (INIS)

Sobotka, L.B.; Sarantities, D.G.; Stracener, D.W.; Majka, Z.; Abenante, V.; Semkow, T.M.; Hensley, D.C.; Beene, J.R.; Halbert, M.L.

1989-01-01

The velocity distribution of fusion-like products formed in the reaction 701 MeV 28 Si+ 100 Mo is decomposed into 26 incomplete fusion channels. The momentum deficit of the residue per nonevaporative mass unit is approximately equal to the beam momentum per nucleon. The yields of the incomplete fusion channels correlate with the Q-value for projectile fragmentation rather than that for incomplete fusion. The backward angle multiplicities of light particles and heavy ions increase with momentum transfer, however, the heavy ion multiplicities also depend on the extent of the fragmentation of the incomplete fusion channel. These data indicate that at fixed linear momentum transfer, increased fragmentation of the unfused component is related to a reduced transferred angular momentum. 22 refs., 6 figs., 1 tab

Low-energy nuclear reactions resulting as parametric interactions with similarity to K-shell electron capture

Energy Technology Data Exchange (ETDEWEB)

Hora, H. [University of New South Wales, Sydney 2052 (Australia); Miley, G.H. [Fusion Studies Laboratory, University of Illinois, Urbana, lL 61801 (United States); Li, X.Z. [Physics Department, Tsinghua University, Beijing 100084 (China); Kelly, J.C. [School of Physics, Sydney University, Sydney 2006 (Australia); Osman, F. [University of Western Sydney, Penrith-Soutti, NSW 1791 (Australia)

2006-07-01

Since the appeal by Brian Josephson at the meeting of the Nobel Laureates July 2004, it seems to be indicated to summarize the following serious, reproducible and confirmed observations on reactions of protons of deuterons incorporated in host metals such as palladium. Some reflections to Rutherford's discovery of nuclear physics, the Cockcroft Oliphant discovery of anomalous low-energy fusion reactions and the chemist Hahn's discovery of fission had to be included. Using gaseous atmosphere or discharges between palladium targets, rather significant results were seen e.g. from the 'life after death' heat production of such high values per host atom that only nuclear reactions can be involved. This supports the earlier evaluation of neutron generation in fully reversible experiments with gas discharges hinting that a reasonable screening effect - preferably in the swimming electron layer - may lead to reactions at nuclear distances d of pico-meters with reaction probability times U of about mega-seconds similar to the K-shell capture radioactivity. Further electrolytic experiments led to low-energy nuclear reactions (LENR) where the involvement of pollution could be excluded from the appearance of very seldom rare earth elements. A basically new theory for DD cross-sections is used to confirm the pico-meter- mega-second reactions of cold fusion. Other theoretical aspects are given from measured heavy element distributions similar to the standard abundance distribution, SAD, in the Universe with consequences on endothermic heavy nuclei generation, magic numbers and to quark-gluon plasmas. (authors)

Observed side feeding in incomplete fusion dynamics in 16O + 160Gd reaction at energy ∼5.6 MeV/A: Spin distribution measurements

Science.gov (United States)

Ali, Rahbar; Afzal Ansari, M.; Singh, D.; Kumar, Rakesh; Singh, D. P.; Sharma, M. K.; Gupta, Unnati; Singh, B. P.; Shidling, P. D.; Negi, Dinesh; Muralithar, S.; Singh, R. P.; Bhowmik, R. K.

2017-12-01

Spin distributions of various residues populated via complete fusion (CF) and incomplete fusion (ICF) reactions in the interaction of 16O with 160Gd at the projectile energy Eproj ∼ 5.6 MeV/A have been studied. The experimentally measured spin distributions of the residues associated with the ICF reactions are found to be distinctly different from those populated via the CF reactions. An attempt has been made to extract the side-feeding pattern from the spin distributions of CF and ICF reaction products. It has been observed that the CF products are strongly fed over a broad spin range. But, no side-feeding takes place in the low observed spins as low partial waves are strongly hindered in the fast α-emission channels (associated with ICF) in the forward direction. It has also been observed that the mean input angular momentum for direct α-emitting (ICF) channels is relatively higher than evaporation α-emitting (CF) channels, and it increases with direct α-multiplicity in forward direction.

Reactions with Weakly Bound Nuclei, at near Barrier Energies, and the Breakup and Transfer Influences on the Fusion and Elastic Scattering

International Nuclear Information System (INIS)

Gomes, P. R. S.; Lubian, J.; Mendes-Junior, D. R.; Faria, P. N. de; Linares, R.; Sigaud, L.; Rangel, J.; Ferreira, J. L.; Paes, B.; Cardozo, E. N.; Cortes, M. R.; Canto, L. F.; Ermamatov, M. J.; Otomar, D. R.; Ferioli, E.; Lotti, P.; Hussein, M. S.

2016-01-01

We present a brief review of the reaction mechanisms involved in collisions of weakly bound projectiles with tightly bound targets, at near-barrier energies. We discuss systematic behaviors of the data, with emphasis in fusion, breakup, nucleon transfer and elastic scattering. The dependence of the breakup cross section on the charge and mass of the target is discussed, and the influence of the breakup channel on complete fusion is investigated. For this purpose, we compare reduced fusion cross sections with a benchmark universal curve. The behaviors observed in the comparisons are explained in terms of polarization potentials and of nucleon transfer followed by breakup. The influence of the breakup process on elastic scattering is also discussed. Some apparent contradictions between results of different authors are explained and some perspectives of the field are presented. (author)

Fusion enhancement/suppression and irreversibility in reactions induced by weakly bound nuclei

International Nuclear Information System (INIS)

Gomes, P.R.S.; Lubian, J.; Canto, L.F.; Chamon, L.C.; Crema, E.; Hussein, M.S.

2011-01-01

We show that halo effects enhance fusion cross sections of weakly bound systems, comparing with the situation when there is no-halo. We introduce dimensionless fusion functions and energy variable quantity to investigate systematical trends in the fusion cross sections of weakly bound nuclei at near-barrier energies. We observe very clearly complete fusion suppression at energies above the barrier due to dynamic effects of the breakup on fusion. We explain this suppression in terms of the repulsive polarization potential produced by the breakup. (author)

Perspectives of fusion power

International Nuclear Information System (INIS)

Jensen, V.O.

1984-01-01

New and practically inexhaustible sources of energy must be developed for the period when oil, coal and uranium will become scarce and expensive. Nuclear fusion holds great promise as one of these practically inexhaustible energy sources. Based on the deuteriumtritium reaction with tritium obtained from naturally occuring lithium, which is also widely available in Europe, the accessible energy resources in the world are 3.10 12 to 3.10 16 toe; based on the deuterium-deuterium reaction, the deuterium content of the oceans corresponds to 10 20 toe. It is presently envisaged that in order to establish fusion as a large-scale energy source, three major thresholds must be reached: - Scientific feasibility, - Technical feasibility, i.e. the proof that the basic technical problems of the fusion reactor can be solved. - Commercial feasibility, i.e. proof that fusion power reactors can be built on an industrial scale, can be operated reliably and produce usable energy at prices competitive with other energy sources. From the above it is clear that the route to commercial fusion will be long and costly and involve the solution of extremely difficult technical problems. In view of the many steps which have to be taken, it appears unlikely that commercial fusion power will be in general use within the next 50 years and by that time world-wide expenditure on research, development and demonstration may well have exceeded 100 Bio ECU. (author)

Stat-of-the art of nuclear fusion and its future outlook in

International Nuclear Information System (INIS)

Abdelaziz, M.E.; Elnadi, A.M.; Masoud, M.; Elshaer, M.A.; Khalil, S.M.

1993-01-01

The study in this project is carried out with the objective of being able to present a clear view for the state-of-the art of nuclear fusion as one of the most promising coming energy source and its future outlook in Egypt. The study introduce a summary of the world energy problem and the advantages of thermonuclear fusion energy compared to other energy sources. A description of the two main techniques of confining plasma in the fusion experiments, namely the magnetic and the inertial confinement. These techniques are discussed and investigated through linear pinches and tokamaks. Tokamaks showed to be a promising machines for achieving the controlled thermonuclear fusion power reactor. Recent development of the research on laser fusion together with fast progress in pellet and laser technology suggest that it may be possible to achieve laser fusion power reactor. The story of the strange phenomena of cold fusion, muon-catalyzed fusion, and cold fusion in condensed matter are also studied and showed to be non promising. The project study in details the future fusion reactor, its nuclear engineering and its safety and environmental aspects. The study is based on the magnetic fusion using the tokamak configuration. The positive safety and environmental aspects of fusion reactors, if exist, is also investigated. Status of plasma physics and nuclear fusion activities and strategies in the developing countries (including egypt and the arab countries) are reviewed, besides, some national programmes are proposed. In addition, the status of international activities in plasma technology and its application are represented. Future outlook for egyptian programmes on different plasma technologies are studied. Finally, conclusions and recommendations are presented which summarized the principle achiements and future research opportunities in nuclear fusion activities. In fact, it must be emphasized that fusion is an exciting and challenging field of research -the most

Analysis of complete fusion excitation functions for 7Li+152Sm, 197Au and 209Bi reactions at around barrier energies

International Nuclear Information System (INIS)

Kharab, Rajesh; Chahal, Rajiv; Kumar, Rajiv

2017-01-01

In the present work we have analyzed the fusion excitation function for CF process using the simple Wong’s formula in conjunction with the energy dependent Woods-Saxon potential (EDWSP) in near barrier energy region for 7 Li+ 152 Sm, 197 Au and 209 Bi reactions

Nuclear structure and fusion at the barrier

International Nuclear Information System (INIS)

Reisdorf, W.

1985-01-01

A comparative study of measured fusion excitation functions in the vicinity of the barrier reveals nuclear structure effects, due in particular to the coupling of the fusion process to direct-reaction channels. (orig.)

Stripping of two protons and one alpha particle transfer reactions for {sup 16} O + {sup A} Sm and their influence on the fusion cross section

Energy Technology Data Exchange (ETDEWEB)

Maciel, A.M.M.; Gomes, P.R.S

1995-12-31

Transfer cross section angular distribution data for the stripping of two protons and one alpha particle are studied for the {sup 16} O + {sup A} Sm systems (A=144, 148, 150, 152 and 154), at near barrier energies. A semiclassical formalism is used to derive the corresponding transfer form factors. For only one channel the analysis shows evidences that the transfer reaction mechanism at backward angles - corresponding to small distances, may behave as a multi-step process leading to fusion. Simplified coupled channel calculations including transfer channels are performed for the study of the sub-barrier of these systems. The influence of short distance transfer reactions on the fusion is discussed. (author) 16 refs., 5 figs., 5 tabs.

Possible in-lattice confinement fusion (LCF). Dynamic application of atomic and nuclear data

International Nuclear Information System (INIS)

Kawarasaki, Yuuki

1995-01-01

New scheme of a nuclear fusion reactor system is proposed, the basic concept of which comes from ingenious combination of hitherto developed techniques and verified facts; 1) so-called cold fusion (CF), 2) plasma of both magnetic confinement fusion (MCF) and inertial confinement fusion (ICF), and 3) accelerator-based D-T(D) neutron source. Details of the LCF reactor physics require dynamics of atomic data as well as nuclear data; interaction of ions with matters in solid and the problems of radiation damage. (author)

Yrast spectroscopy in {sup 49-51}Ti via fusion-evaporation reaction induced by a radioactive beam

Energy Technology Data Exchange (ETDEWEB)

Niikura, M.; Ideguchi, E.; Michimasa, S.; Ota, S.; Shimoura, S.; Wakabayashi, Y. [University of Tokyo, Center for Nuclear Study, Wako, Saitama (Japan); Aoi, N.; Baba, H.; Fukuchi, T.; Ichikawa, Y.; Kubo, T.; Kurokawa, M.; Ohnishi, T.; Suzuki, H.; Yoshida, K. [RIKEN Nishina Center, Wako, Saitama (Japan); Iwasaki, H.; Onishi, T.K.; Suzuki, D. [University of Tokyo, Department of Physics, Tokyo (Japan); Liu, M.; Zheng, Y. [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China)

2009-12-15

In-beam {gamma} -ray spectroscopy of high-spin states in {sup 49-51}Ti was performed via the fusion-evaporation reaction using a radioactive beam. By excitation function and {gamma} - {gamma} coincidence analysis, yrast high-spin levels up to I=(21/2{sup -}),(11{sup +}),(17/2{sup -}) in {sup 49-51}Ti were determined. The levels were compared with full-pf -shell model calculation. The level structure indicates the persistency of the N=28 shell gap at yrast states in {sup 49-51}Ti. (orig.)

Application of polarized nuclei to fusion

International Nuclear Information System (INIS)

Kulsrud, R.M.

1987-07-01

It is shown that the d-t fusion reaction can be modified by polarizing nuclear spins. The ways in which this improves reactor performance are mentioned and the feasibility of the process of spin polarization for magnetic fusion is discussed. 18 refs

Gross resonance-like structure of the complete fusion excitation function for the 16O + 28Si reaction

International Nuclear Information System (INIS)

Zheng Jiwen; Zheng Pingzi; Liu Guoxing

1993-01-01

The complete fusion excitation function for the 16 O + 28 Si reaction is measured in the incident energy range from 50 to 90 MeV with step of 1.0 MeV using a position sensitive ΔE-E telescope system. The striking gross resonance-like structure is observed when E c.m. c.m. 34.5, 38.5 and 43.0 MeV respectively. The structure vanishes gradually when E c.m. > 46.0 MeV

An electrolytic route to fusion?

International Nuclear Information System (INIS)

Anon.

1992-01-01

A patent has been granted by the Swedish Patent Authority for a new process to initiate and control energy generation through fusion reactions of hydrogen. According to the patent-holder, the Swedish company AB Technology Development, the fusion power process could be available for commercial applications within 4-5 years if laboratory and pilot plant tests prove successful. The new process employs a high voltage discharge in heavy water to create conditions under which, according to the patent holder, a high probability of fusion is achieved without the extraordinary high temperatures required in a conventional fusion reactor. (author)

Inertial fusion with hypervelocity impact

International Nuclear Information System (INIS)

Olariu, S.

1998-01-01

The physics of the compression and ignition processes in inertial fusion is to a certain extent independent of the nature of the incident energy pulse. The present strategy in the field of inertial fusion is to study several alternatives of deposition of the incident energy, and, at the same time, of conducting studies with the aid of available incident laser pulses. In a future reactor based on inertial fusion, the laser beams may be replaced by ion beams, which have a better energy efficiency. The main projects in the field of inertial fusion are the National Ignition Facility (NIF) in USA, Laser Megajoule (LMJ) in France, Gekko XII in Japan and Iskra V in Russia. NIF will be constructed at Lawrence Livermore National Laboratory, in California. LMJ will be constructed near Bordeaux. In the conventional approach to inertial confinement fusion, both the high-density fuel mass and the hot central spot are supposed to be produced by the deposition of the driver energy in the outer layers of the fuel capsule. Alternatively, the driver energy could be used only to produce the radial compression of the fuel capsule to high densities but relatively low temperatures, while the ignition of fusion reactions in the compressed capsule should be effected by a synchronized hypervelocity impact. Using this arrangement, it was supposed that a 54 μm projectile is incident with a velocity of 3 x 10 6 m s -1 upon a large-yield deuterium-tritium target at rest. The collision of the incident projectile and of the large-yield target takes place inside a high-Z cavity. A laser or heavy-ion pulse is converted at the walls of the cavity into X-rays, which compresses the incident projectile and the large-yield target in high-density states. The laser pulse and the movement of the incident projectile are synchronized such that the collision should take place when the densities are the largest. The collision converts the kinetic energy of the incident projectile into thermal energy, the

Plasma physics for controlled fusion

CERN Document Server

Miyamoto, Kenro

2016-01-01

This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator includi...

Fusion, magnetic confinement

International Nuclear Information System (INIS)

Berk, H.L.

1992-01-01

An overview is presented of the principles of magnetic confinement of plasmas for the purpose of achieving controlled fusion conditions. Sec. 1 discusses the different nuclear fusion reactions which can be exploited in prospective fusion reactors and explains why special technologies need to be developed for the supply of tritium or 3 He, the probable fuels. In Sec. 2 the Lawson condition, a criterion that is a measure of the quality of confinement relative to achieving fusion conditions, is explained. In Sec. 3 fluid equations are used to describe plasma confinement. Specific confinement configurations are considered. In Sec. 4 the orbits of particle sin magneti and electric fields are discussed. In Sec. 5 stability considerations are discussed. It is noted that confinement systems usually need to satisfy stability constraints imposed by ideal magnetohydrodynamic (MHD) theory. The paper culminates with a summary of experimental progress in magnetic confinement. Present experiments in tokamaks have reached the point that the conditions necessary to achieve fusion are being satisfied

Fusion, resonances and scattering in C reaction

Indian Academy of Sciences (India)

respectively. In each of these regions, we find some important features in the results ofσfus. ... draws attention in the astrophysical studies [2,7]. Here, Ecm and η .... We outline the concept of selective resonance tunneling for fusion in Ü3. In Ü4 ...

Unichannel description of the fusion reactions

International Nuclear Information System (INIS)

Franzin, V.L.M.

1987-01-01

Using an effective one channel model which contains channel coupling effects through the presence of an inclusive energy - dependent polarization potential it was studied sub-barrier fusion of the systems A1 Ni+ A2 N1 and 16 O+ A Sm. The consistency of this method is checked by comparing this empirical polarization potential with the one determined from the explicit consideration of a specific channel coupling. (A.C.A.S.) [pt

$\\gamma$ -spectroscopy of n-rich $^{95,96}$Rb nuclei by the incomplete fusion reaction of $^{94}$Kr on $^{7}$Li

CERN Multimedia

We propose an experiment with MINIBALL coupled to T-REX to investigate n-rich $^{95,96}$Rb nuclei by the incomplete fusion reaction of $^{94}$Kr on $^{7}$Li. The nuclei of interest will be populated by transfer of a triton into $^{94}$Kr, forming the excited $^{97}$Rb nucleus, followed by the emission of an alpha particle, which will be detected in the Si telescopes of T-REX. The $^{97}$Rb product will evaporate 1 or 2 (with the highest probability) neutrons leading to $^{96}$Rb or $^{95}$Rb, respectively. The aim of the experiment is twofold: \\\\ i) to perform a $\\gamma$- spectroscopy study of $^{95,96}$Rb nuclei with N=58,59, the structure of which is of particular interest in investigating the transition towards stable deformation at N=60, \\\\ ii) to acquire experience in using incomplete fusion reactions with the weakly bound $^{7}$Li target, in order to perform, at a later stage with HIE-ISOLDE, similar measurements induced by n-rich radioactive beams of Sn and Hg, for which at least 5 MeV/nucleon are need...

Pulsed fission/fusion hybrid engines

International Nuclear Information System (INIS)

Hudson, G.C.

1979-01-01

Research into high-thrust, high-specific impulse rocket engines using energy from nuclear reactions which has been conducted at this organization will be discussed. The engines are all conceptual in nature, yet are within the realization of conventional or near-term technology. The engine concepts under study at Foundation, Inc. are designed to obviate or minimize these negative effects of the ORION scheme. By using non-chemical triggers to initiate a non-breakeven fusion reaction at the core of a target composed of both fission and fusion fuel, it should be possible to employ the fusion neutrons thus produced to begin a fission reaction in U-235 or Pu-239. Since the density of the target can be increased by as much as a factor of 250 through compression of the pellet, the amount of fission material necessary to produce a critical mass can be greatly reduced. (This also means that the amount of fission products produced for a giventhrust level is also reduced from the ORION levels.) Coupling this eeffect to the large number of 14 MeV fusion neutrons produced early in the compression process and subsequently to the heating of some additional fusion fuel surrounding the critical mass leads to the very efficient burnup of the target. This insures both high yield from the target as well as low cost per MJ energy released. Finally, the use of such small pellets allows the scale of the energy released to be tailored to a level usable in rocket engines of a few tens of tons thrust level. (orig.) [de

Influence of projectile α-breakup threshold on complete fusion

International Nuclear Information System (INIS)

Mukherjee, A.; Subinit Roy; Pradhan, M.K.; Saha Sarkar, M.; Basu, P.; Dasmahapatra, B.; Bhattacharya, T.; Bhattacharya, S.; Basu, S.K.; Chatterjee, A.; Tripathi, V.; Kailas, S.

2006-01-01

Complete fusion excitation functions for B11,10+Tb159 have been measured at energies around the respective Coulomb barriers, and the existing complete fusion measurements for Li7+Tb159 have been extended to higher energies. The measurements show significant reduction of complete fusion cross sections at above-barrier energies for both the reactions, B10+Tb159 and Li7+Tb159, when compared to those for B11+Tb159. The comparison shows that the extent of suppression of complete fusion cross sections is correlated with the α-separation energies of the projectiles. Also, the two reactions, B10+Tb159 and Li7+Tb159 were found to produce incomplete fusion products at energies near the respective Coulomb barriers, with the α-particle emitting channel being the favoured incomplete fusion process in both the cases