The mechanisms and the features of the main types of nuclear ternary fission (that is, true ternary fission, in which a third particle is emitted before the rupture of the fissioning nucleus into fragments, and delayed ternary fission, in which a third ...

We present the first results on the bremsstrahlung emission of photons accompanying ternary spontaneous fission of the 252Cf nucleus. We also compare our calculations on the basis of quantum model with preliminary experimental data and find a good agreement between theory and experiment for photon energies up to 500 keV, when the ...

For the study of 252Cf ternary fission measurement was performed using Gammasphere and eight ?E-E silicon particle telescopes. Gamma ray spectra were investigated for the ternary fission accompanied by helium, beryllium, and carbon light charged particles (LCPs) emitted with kinetic energy more ...

The {ital P}-odd asymmetry coefficient has been measured in emission of fragments from fission of {sup 240}Pu accompanied by a long-range {alpha} particle (ternary fission). The {ital P}-odd asymmetry coefficient was measured simultaneously in the same apparatus for fission into two fragments. ...

In an experiment carried out at the 4? Ge detector facility Gammasphere the yields of ternary fission events of 252Cf accompanied by the emission of He, Be and C LCPs were measured. For the first time independent yields were measured for 59 pairs of secondary fragments of the He ternary fission ...

In a systematic survey of ternary fission induced by thermal neutrons at the Lohengrin spectrometer of the ILL/Grenoble, the target nucleus249Cf has recently been added to the list of actinides under study. Special emphasis was put on the search for the heaviest ternary particles. At the limit of detection (some 10?9 per ...

Light charged particles (LCP) and fission elements formed in ternary fission of /sup 252/Cf have been investigated. The energy spectra of light particles, alphas, and protons were studied using a ..delta.. E X (E + ..delta.. E) particle-identifying telescope apparatus. A coincidence circuit was used in such a way that the K x rays from ...

Ternary fragmentation by calculating the potential energy surfaces (PES) with the inclusion of deformation and orientation degrees of freedom for the 4He- and 10Be-accompanied fission of the 252Cf nucleus is studied. The most favored ternary fragmentation channels in the light charged particles (4He and/or ...

This is a report on experimental results obtained with the double torus ionization chamber 'DIOGENES', which has been developed for the investigation of particle associated fission. The role of ternary fission for the understanding of the fission will be ...

A survey was made of experimental information pertinent to the probability of ternary fission and the charge distribution of the light ternary fission products. A new prescription is presented for the ternary fission probability as a function of incident ...

The relative {sup 4}He and {sup 5}He ternary fission yields were determined from a careful analysis of the energy distribution of {alpha} spectra from a new measurement with a {sup 252}Cf source and from published data on {sup 252}Cf and {sup 235}U(n,f). The kinetic energies of the {sup 5}He and {sup 4}He ternary particles were found ...

The ternary fragmentation of 252Cf for all possible third fragments has been investigated using the recently proposed three-cluster model within a spherical approximation and satisfying the condition A 1 ? A 2 ? A 3 . The most probable ternary configurations in the fission of 252Cf accompanied with all possible ...

Values of effects of parity nonconservation in binary and ternary fission of plutonium 239 by polarized thermal neutrons were measured simultaneously. The ratio of asymmetry coefficient (AC) of ternary fission to the AC of binary fission was equal to 0.67...

New hypotheses concerning the origin of the light charged particles emitted in ternary fission and in fusion-fission reactions are presented. They lead to a precise prediction of atomic number and mass of the heaviest detectable ternary L.C.P.'s.

A survey was made of experimental information pertinent to the probability of ternary fission and the charge distribution of the light ternary fission products. A new prescription is presented for the ternary fission probability as a function of incident particle energy and ...

The high selectivity and sensitivity offered by large detector arrays such as Gammasphere and Eurogam enable one to identify gamma rays from individual neutron-rich nuclei produced in the spontaneous fission (SF) of {sup 252}Cf and {sup 248}Cm. We have identified new {gamma} transitions in {sup 101,102,103}Nb, {sup 98,100}Y, {sup 103,107,109}Mo and {sup 109,111}Ru. In Nb ...

The high selectivity and sensitivity offered by large detector arrays such as Gammasphere and Eurogam enable one to identify gamma rays from individual neutron-rich nuclei produced in the spontaneous fission (SF) of 252Cf and 248Cm. We have identified new ? transitions in 101,102,103Nb, 98,100Y, 103,107,109Mo and 109,111Ru. In Nb nuclei we observed pairing-free rotational ...

Calculated ternary fission barriers of superheavy nuclei are found to exceed the binary barriers by only 10--35 percent. The importance for the discovery of superheavy nuclei is discussed. (auth)

A new kinematic study on the ternary fission of (sup 252)Cf has been conducted by registering prompt neutrons and fission (gamma) rays coincidence with light charged particles (LCP) and fission fragments. The aim is to investigate changes in fragment defo...

Tripartition in the spontaneous fission of sup 252 Cf was studied by measuring both the energy and angular distribution of ternary fragments with a toroidal position sensitive ionization chamber. Most registered ternary events are identified as light char...

The cross sections for the binary and ternary fission of thorium induced by 14, 18, and 23 GeV protons were determined. A polycarbonate (macrofol) was used as the detector of fission fragments. (GE)

Contents: How fission was discovered; Photofission; Neutron induced fission below and at the barrier; Application of some fission properties to neutron dosimetry; Alpha-particles during nuclear fission; Ternary fission experiments; Neutron induced ...

All possible ternary fragmentations in fission of Cf252 are studied in collinear configuration within a spherical approximation using the recently proposed �three cluster model.� The potential energy surface of collinear configuration exhibits a strong valley around Ca48 and its neighboring nuclei Ca50, Ti54, and Cr60. Such strong minima are not seen ...

To compare with the wealth of new data on alpha-accompanied fission of 236U* we have made new trajectory calculations. Initial conditions for several parameters were selected from Gaussian distributions by the Monte Carlo method and about 15 000 trajectories were run for an alpha source at the electrostatic saddle point. Momentum and energy are fully ...

In this thesis on a measurement of the ternary fission of sup 252 Cf is reported. The relevant parameters for the mass determination energies and angles between the fragments were measured in coincidence. During a measurement time of 100 days 3 events wer...

Ternary and binary fission barriers and their relative WKB penetrability have been calculated for the isotopes 184 < or = N < or = 228 of element 126, considering both Z = 114 or Z = 126 as magic numbers. In all cases the predicted relative rates GAMMA/sub T//GAMMA/sub B/ of ternary to binary low-energy ...

A dynamical model is proposed for the formation of light charged particles in nuclear fission, based on the assumption that the light particles appear owing to the occurrence of two breaks in a neck of finite thickness during a time of the order of a period of the one-particle motion. On the basis of a simplified semiclassical treatment of the descent from the saddle point, ...

The values of angular anisotropy of fragments in binary and ternary fission of 235U induced by 3 MeV neutrons have been determined with two independent methods. In the first method fission fragments and long range alpha particles were detected with a gridded ionization chamber and a CSI crystal respectively and in the second method ...

In the framework of quantum-mechanical fission theory, the method of calculation for partial fission width amplitudes and asymptotic behavior of the fissile nucleus wave function with strong channel coupling taken into account has been suggested. The method allows one to solve the calculation problem of angular and energy distribution countation for binary ...

A new phenomenon is studied: the cold (neutronless) ternary ?-accompanied fragmentation of 252Cf. The corresponding isotopic yields were calculated as the ratio of the penetrability of a given fragmentation over the sum of penetrabilities of all possible (neutronless) ?-ternary fragmentations. No preformation factors were considered. ...

Ternary fission constitutes an important source of helium and tritium gas production in nuclear reactors and in used fuel elements. Data related to this production are therefore requested by nuclear industry. In the present paper, we report results from measurements of the 4He and 3H emission probabilities (denoted LRA/B and t/B, respectively). These ...

Ternary fission constitutes an important source of helium and tritium gas production in nuclear reactors and in used fuel elements. Data related to this production are therefore requested by nuclear industry. In the present paper, we report results from measurements of the 4He and 3H emission probabilities (denoted LRA/B and t/B, respectively). These ...

Inducing fission by polarized neutrons allows studying subtle effects of the dynamics of the process. In the present experiments ternary fission of 235U and 239Pu was investigated with cold neutrons in the (n,f) reaction at the Institut Laue-Langevin, Grenoble. Asymmetries in the emission of ternary particles were ...

The phenomenon of cold (neutronless) alpha ternary fission in spontaneous fission of {sup 252}Cf was experimentally observed by triple gamma coincidence technique with Gammasphere with 72 gamma-ray detectors. Correlated pairs of {sub 36}Kr-{sub 60}Nd, {sub 38}Sr-{sub 58}Ce, {sub 40}Zr-{sub 56}Ba, {sub 42}Mo-{sub 54}Xe, {sub 44}Ru-{sub ...

The half-lives of cluster emitters predicted by the analytical superasymmetric fission model have been experimentally confirmed. Potential energy surfaces of cluster emitters are showing deep valleys due to the strong shell effect of the doubly magic daughter 208Pb. Cluster radioactivities allow us to study transitions from a deformed parent nucleus, with a complex structure ...

Results of the first direct observation of the true ternary fission of 234Pa* nucleus are presented. The yield of the effect depending of the experimental geometry is about 10-5/binary fission. Mass of the lightest fragment in the triplet lies mainly in the range of (20�40) a.m.u. Connection between the effect and known heavy ion or ...

Within quantum-mechanical fission theory, P-odd and P-even correlations in angular distributions of products of the ternary fission of nuclei that is induced by polarized cold and thermal neutrons are investigated on the basis of a nonevaporative mechanism of third-particle emission and under the assumption that a two-humped ...

High resolution measurements of prompt ?-rays emitted from fission fragments accompanied by light charged particles (LCP) and those emitted from normal binary fission fragments in 252Cf fission were simultaneously carried out using a 30 cm3 Ge(Li) detector. A ``sandwich'' type of arrangement in the source-detector ...

The results of multiparameters measurements in binary and ternary spontaneous fission of (sup 252)Cf are described. In the neasurements the fragment kinetic energies and the numbers of neutrons emitted by each complementary fragment were registered. The f...

Ternary events in the thermal neutron induced fission of {sup 241}Pu were studied with the recoil separator LOHENGRIN at the Institut Laue Langevin in Grenoble. Yields and energy distributions could be determined for most isotopes of the elements hydrogen to oxygen. Also several heavier nuclei up to {sup 30}Mg could be observed. Yields were measured for 42 ...

21. TERNARY FISSION OF URANIUM NUCLEI INDUCED BY HIGH-ENERGY PROTONS By R. BRANDT (1), F. CARBONARA mica pour l'�tude de la fission ternaire de 1'uranium. L'existence de ce processus a �t� �tablie sans ambigu�t� pour des protons incidents de 23 GeV. Les valeurs mesur�es des sections efficaces de ...

Prospects for further studies of TRI and ROT effects of T-odd asymmetry in the emission of light particles in the ternary and binary fission of heavy nuclei that is induced by slow polarized neutrons are considered with a view to studying the mechanism for the formation of these effects and using them to get new information about ...

The emission probabilities and the energy distributions of tritons, ? and 6He particles emitted in the spontaneous ternary fission (zero excitation energy) of 250Cf and 252Cf and in the cold neutron induced fission (excitation energy ?6.5 MeV) of 249Cf and 251Cf are determined. The particle identification was done with suited ?E-E ...

The emission probabilities and the energy distributions of tritons and ? particles emitted in the spontaneous ternary fission (zero excitation energy) of 244Cm, 246Cm and 248Cm and in the cold neutron induced fission (excitation energy ?6.5 MeV) of 243Cm, 245Cm and 247Cm are determined. The particle identification was done with suited ...

This chapter first gives a survey on the history of the discovery of nuclear fission. It briefly presents the liquid-drop and shell models and their application to the fission process. The most important quantities accessible to experimental determination such as mass yields, nuclear charge distribution, prompt neutron emission, kinetic energy ...

Effects of T-odd asymmetry in ternary-nuclear-fission reactions induced by polarized cold neutrons are considered within quantum theory. It is shown that the asymmetry coefficient can be expressed in terms of experimental angular distributions of third particles in reactions induced by unpolarized neutrons. The explicit form of this coefficient makes it possible to explain the ...

A quantum version of a unified description of two T-odd effects recently observed in the ternary fission of nuclei that is induced by polarized neutrons is considered. These effects are explained by the effect of the Coriolis interaction of the rotating fissile system on the angular distributions of light charged particles in the interior and exterior ...

Within the frameworks of statistical model the most probable charges, common excitation energy of ternary fission fragments for (sup 232)Th, (sup 235,238)U, (sup 237)Np, (sup 239)Pu, (sup 241)Am and (sup 249)Cf are obtained. 6 refs.; 14 figs. (Atomindex c...

Precise data are developed on linetic energy distribution among fragments of ternary fission. An ionization chamber equipped with a filter and designed for separately recording of fission fragments and long-range alpha particles was used. Some 17644 ternary fissions were recorded, and ...

During the last years, several Cm and Cf isotopes have been studied by our research group in the frame of a systematic investigation of gas emission characteristics in ternary fission. Here we report on new results on the energy distribution and the emission probability of 3H, 4He and He particles emitted in the spontaneous ternary ...

The fabrication and use of gold-germanium and goldsilicon surface- barrier detectors for the detection and energy measurements of fission fragments are discussed. Measurements are presented of the energy spectrum of th alpha - particles from uranium, and of the fission fragments from neutron-induced fission of U/sup 235/. A ...

Two samples of Madagascar monazite from the same geological formation as the biotite studied by Gentry et al. were examined by using a neutron multiplicity counter capable of detecting binary or ternary spontaneous fission decay in any element. No events characteristic of spontaneous fission decay of superheavy elements were found. ...

Results of the first direct observation of the true ternary fission of 234Pa* nucleus are presented. The yield of the effect depending on the experimental geometry is about 10?5/binary fission. Mass of the lightest fragment in the triplet lies mainly in the range of 20-40 a.m.u. An intimate connection between the effect and known ...

The existing ternary fission models can well reproduce the yields of the most abundant light charged particles. However, these models tend to significantly overestimate the yields of ternary particles with an extreme N/Z ratio: {sup 3}He, {sup 11}Li, {sup 14}Be, etc. The experimental yields of these isotopes were investigated with the ...

the collision of very heavy nuclei 197Au+197Au at 15 A MeV has been studied within the improved quantum molecular dynamics model. A class of ternary events satisfying nearly complete balance of mass numbers is selected. The experimental mass distributions for the system 197Au+197Au ternary fission fragments, the heaviest (A1), the ...

Ternary fission of {sup 252}Cf was studied at Gammasphere using eight {delta}E x E particle telescopes. Helium, beryllium, boron, and carbon light charged particles (LCPs) emitted with kinetic energy more than 9, 21, 26, and 32 MeV, respectively, were identified. The 3368-keV {gamma} transition from the first 2{sup +} excited state in {sup 10}Be was found ...

Gold-silicon surface barrier detectors approximately 3/4" in diameter are used in several experiments on the fission process. A pair of detectors, with detecting surfaces parallel and facing each other at a distance comparable with their diameters and with U/sup 235/ deposited on one detector, is used to measure the mass distribution in thermal neutron ...

A new detector system for the comprehensive investigation of light charged particle accompanied fission is described. First experimental results obtained on neutron induced fission of 235U at the high-flux reactor of the ILL are used to discuss the properties of the system.

The probabilities of U/sup 233/, Pu/sup 23>/, and Pu/sup 241/ >s ternary fission were correlated with U/sup 235/ probability. Layers of fissionable material 0.1 to 0.2 mg/cm/sup 2/ were placed on transparent nylon film. The isotopic compositions were determined by measuring alpha activity, spontaneous ...

Ternary fission of the standard reaction 235U(nth,f) induced by cold polarized neutrons has been investigated. Fission fragments and light charged particles were recorded in coincidence. Following cold neutron capture the compound nucleus 236U* has spin 3- or 4-. At the saddle point of the fissioning 236U* nucleus ...

The emission of {sup 10}Be in ternary cold neutronless spontaneous fission of {sup 252}Cf is observed with the Gammasphere consisting of 72 detectors. The {gamma} ray corresponding to the decay of the first 2{sup +} state in {sup 10}Be is observed in coincidence with the {gamma} rays of the fission partners of {sup 96}Sr and {sup ...

Tritium is formed in thermal nuclear reactors both by neutron activation of elements such as deuterium and lithium and by ternary fission in the fuel. It is a weak beta-emitter with a short half-life, 12.3 years, and its radiological significance in react...

The tritium produced by ternary fission within spent fuel will be in most part as HTO form in aqueous effluents of the reprocessing plant. Its decharge to the environment will prove detrimental and studies have been undertaken to develop techniques to con...

Using a unique two-arm detector system for heavy ions (BRS, binary reaction spectrometer) coincident fission events have been measured from the decay of 60Zn and 56Ni compound nuclei formed at 83-88 MeV excitation energy. From the binary coincidences inclusive and exclusive cross sections for fission channels with differing losses of charge were obtained. ...

Tritium is formed in thermal nuclear reactors both by neutron activation of elements such as deuterium and lithium and by ternary fission in the fuel. It is a weak beta-emitter with a short half-life, 12.3 years, and its radiological significance in react...

In thermal neutron-induced and spontaneous fission the addition of two neutrons to a neutron-even system produces only minor changes to the shape, kinetic energy, and temperature of the scission configuration. If these changes are assumed negligible and if ternary fission is associated with a statistical process then the ratio of ...

The systematics of the low energy fission of the fermium isotopes is studied considering half-lives, masss division, kinetic-energy release, and accompanying prompt neutron emission. It is shown that the low energy fission of the fermium isotopes is a microcosm of the fission process, exhibiting a wide range of ...

Conditions for the appearance and observation of prescission gamma rays emitted by a fissioning nucleus prior to its separation into fission fragments were investigated within quantum-mechanical fission theory. It is shown that these conditions are realizable in the gamma decay of isovector electric giant dipole resonances in a fissile ...

Recent models as well as new trajectory calculations used to interpret the experimental data on alpha -accompanied fission are presented and experimental hints towards the emission mechanism are pointed out. The important question of the distribution of t...

First results are presented of an investigation of the properties of gamma radiation accompanying the population of the spontaneously fissioning isomer /sup 242m/Am in the thermal neutron capture reaction.

Double-differential emission probabilities W ?( ? ?, LF E ?) in angle ? ?, LF and energy E ? for prompt ?-rays have been measured in the spontaneous fission of252Cf. The detector system allowed the ?-deexcitation in both the binary and the light charged particle accompanied fission modes to be studied under equal conditions. Previous ...

A study of the gamma emission accompanying the spontaneous fission process of 252Cf has been performed. The photon emission probability between 3 and 70 MeV and its angular dependence with respect to the fission direction were measured. These measurements were performed as a function of the mass asymmetry of the ...

Mass, energy and folding angle distributions of the fission fragments as well as multiplicities of neutron and gamma-quanta emissions accompanying the fission process were measured for fission of 226Th, 227Pa and 234Pu compound nuclei produced in reactions with 18O and 26Mg projectiles over a wide energy range. ...

A radiochemical investigation has been made of the fission yield curve for the spontaneous fission of Cf252. One source of 1�106, another of 2�107, and a third of 7�107 fissions per minute were used to obtain the data. Thirty-six radioactive nuclides between mass numbers 77 and 166 were separated, identified, and their ...

Using a unique two-arm detector system for heavy ions (the BRS, binary reaction spectrometer), coincident fission events have been measured from the decay of {sup 60}Zn compound nuclei formed at 88 MeV excitation energy in the reactions with {sup 36}Ar beams on a {sup 24}Mg target at E{sub lab}({sup 36}Ar)=195 MeV. The detectors consisted of two large-area position-sensitive ...

Using a unique two-arm detector system for heavy ions (the BRS, binary reaction spectrometer), coincident fission events have been measured from the decay of Zn60 compound nuclei formed at 88 MeV excitation energy in the reactions with Ar36 beams on a Mg24 target at Elab(36Ar)=195 MeV. The detectors consisted of two large-area position-sensitive (x,y) gas telescopes with ...

True ternary fission with formation of a heavy third fragment is quite possible for superheavy nuclei because of the strong shell effects leading to a three-body clusterization with the two doubly magic tinlike cores. The simplest way to discover this phenomenon in the decay of excited superheavy nuclei is a detection of two tinlike clusters with ...

Angular distributions of light charged particles relative to the momentum of the light fission fragment were studied in ternary fission induced by cold polarized neutrons. It was discovered that the angular distribution is asymmetric with respect to a plane determined by the direction of incident neutron spin and the light fragment ...

Investigation of the {sup 235}U(n{sub th}, f) reaction using the miniFOBOS double-arm time-of-flight spectrometer of fission fragments confirmed manifestations of the earlier unknown many-body, at least ternary, decay involving almost collinear decay-product escape, which were first observed in the spontaneous fission of {sup ...

Investigation of the 235U( n th, f) reaction using the miniFOBOS double-arm time-of-flight spectrometer of fission fragments confirmed manifestations of the earlier unknown many-body, at least ternary, decay involving almost collinear decay-product escape, which were first observed in the spontaneous fission of 252Cf(sf). The use of ...

Superconductivity and magnetism in the new group of rare-earth ternary borides, MRh sub 4 B sub 4 , has been reported recently by Matthias et al. Particularly striking has been their observation of reentrant magnetism accompanying the return to a normal s...

This experiment investigates the variation of the correlation between the average energy of long-range alpha (LRA) particles and the fragment-mass ratio with the total kinetic energy of the fragments and studies the dependence of the correlation between the average energy of LRA particles and total kinetic energy of the fragments on the fragment mass ratio. In addition, other correlations in ...

Mica track detectors were used to measure the fission cross sections of U, Bi, and Au irradiated with 2.5-GeV/c antiprotons and negative pions. The binary-fission results in mb are: U, 2170 +/- 330 for p� and 1090 +/- 160 for ?- Bi, 293 +/- 60 for p� and 191 +/- 40 for ?- Au, 210 +/- 40 for p� and 107 +/- 20 for ?-. The ?- cross sections are about ...

In the system 200 MeV sup 37 Cl+ sup 124 Sn the angular correlation of the alpha particles emitted before fission in coincidence with fission fragments was measured relatively to the spin direction of the compound-nucleus system sup 161 Ho*. Identificatio...

Study of the T-odd three-vector correlation in the emission of prompt neutrons from 235U fission by polarized cold neutrons has been continued at the facility MEPHISTO of the FRM II reactor (Technical University of Munich). The sought correlation was not found within experimental error of 2.3 � 10-5. The upper limit for the asymmetry coefficient has been set to | D n | < ...

Ternary events originating from the 197Au + 197Au reaction at 15 MeV/nucleon, studied by using the multidetector array CHIMERA at LNS Catania, have been collected in almost complete 2? range of the forward hemisphere of CHIMERA thus extending the angular range of our previously reported preliminary data. Energy- and time calibrations for heavy fragments at large angles were ...

The cytoplasmic dynamin-related guanosine triphosphatase Drp1 is recruited to mitochondria and mediates mitochondrial fission. Although the mitochondrial outer membrane (MOM) protein Fis1 is thought to be a Drp1 receptor, this has not been confirmed. To analyze the mechanism of Drp1 recruitment, we manipulated the expression of mitochondrial fission and ...

An experimental investigation of ?-particle emission in the spontaneous fission of Cf252 is described. The measured angular distribution and energy distribution of the ? particles are presented, as well as the mass-ratio distribution of the fission fragments and the single-fragment energy distribution in fission ...

The results of an experiment aimed at searches for formally T-odd correlations in the angular distribution of prompt neutrons from the fission of {sup 235}U nuclei are presented. The experiment was performed in the MEPHISTO polarized cold-neutron beam from the Munich FRMII reactor. The correlation coefficient proved to be (-3.5 {+-} 3.4) x 10{sup -5} for a three-vector ...

The results of an experiment aimed at searches for formally T-odd correlations in the angular distribution of prompt neutrons from the fission of 235U nuclei are presented. The experiment was performed in the MEPHISTO polarized cold-neutron beam from the Munich FRMII reactor. The correlation coefficient proved to be (-3.5 � 3.4) � 10-5 for a three-vector correlation (TRI ...

We discuss the effect of kinetic energy of the relative motion becoming spurious for separate fragments on the selfconsistent mean-field fission barriers. The treatment of the relative motion in the cluster model is contrasted with the necessity of a simpler and approximate approach in the mean-field theory. A scheme of the energy correction to the Hartree-Fock is proposed. ...

The hard electric dipole radiation from fission fragments of 235U by thermal neutrons is predicted. The radiation arises due to the Strutinsky-Denisov-induced polarisation mechanism. The probability of the radiation is at the level of 0.0025 per fission, which is in agreement with experiment. The angular distribution exhibits left-right asymmetry with ...

Kinematically complete experiments have been performed on the two- and three-body exit channels in the reactions84Kr+166Er and129Xe+122Sn at 12.5 MeV/u. Three-body events occur with an unusually high probability. They arise from a fast two-step mechanism where a sequential fission-like process follows a deep inelastic collision with preferentially very large energy losses. ...

For increasing the retention of solid fission products in coated fuel particles, investigations were made on oxide fuel kernels containing special refractory oxides, e,g., Al/sub 2/O/sub 3/. It was the aim of this work to test the possibility of retaining solid fission products in the kernel by formation of stable ternary ...

The emission of light charged particles from heavy fragments of uranium fission induced by 153-MeV protons is studied. The probability of their emission is 2.7 x 10{sup - 2} per fission event. It is found that these particles affect the distribution of angles of fragment divergence and the angular distribution of heavy fragments with respect to the ...

Additions of aluminium oxide and silicon oxide to ceramic fuel for pyrocarbon-coated nuclear fuel particles counteracts a release of fission-cesium by compound formation. The vaporization tests carried out here using samples from the quasi-ternary system ...

Mitochondria are present as tubular organelles in neuronal projections. Here, we report that mitochondria undergo profound fission in response to nitric oxide (NO) in cortical neurons of primary cultures. Mitochondrial fission by NO occurs long before neurite injury and neuronal cell death. Furthermore, fission is ...

Exclusive measurements of two- and three-body events were performed for the system 120Sn+100Mo at 19.1 MeV/nucleon. Most ternary events are consistent with sequential processes in which one of the two deep-inelastic fragments fissions. For such events large differences are found between the fission probabilities of projectilelike and ...

The molten salt Flibe, a combination of lithium and beryllium fluorides studied for molten salt fission reactors, has been proposed as a breeder and coolant for fusion applications. The melting points of 2LiF-BeF{sub 2} and LiF-BeF{sub 2} are 460 deg. C and 363 deg. C, but LiF-BeF{sub 2} is rather viscous and has less lithium for breeding. In the Advanced Power Extraction ...

We present a model of near-Earth asteroid (NEA) rotational fission and ensuing dynamics that describes the creation of synchronous binaries and all other observed NEA systems including: doubly synchronous binaries, high-e binaries, ternary systems, and contact binaries. Our model only presupposes the Yarkovsky�O'Keefe�Radzievskii�Paddack (YORP) ...

The binary and ternary products from reactions of sup 238 U beams with targets of sup 16 O, sup 27 Al, sup 48 Ca, sup 45 Sc, sup 48 Ti, sup 58 Fe, sup 64 Ni and sup 89 Y have been recorded at 6.0 MeV/u bombarding energy with four position-sensitive avalan...

Proof-of-principle measurements are reported demonstrating that multiplicity techniques can be used to identify prompt fission neutrons from photonuclear interrogation under circumstances where the fission neutrons may be accompanied by photodissociated neutrons of an identical energy spectrum, and where the emitted neutrons are ...

Spontaneous fission of ^252Cf was studied with 8 light charged particle detectors in Gammasphere. With a 62 ?C source, 5.7x10^11 triple-coincidence events were recorded. In coincidence with LCP, the ?-? matrix was analyzed. We obtained the relative yields of fission fragment pairs as a function of the neutron number. In the Ba-?-Zr and Mo-?-Xe splits, the ...

Spontaneous fission of 252Cf was studied with 8 light charged particle detectors in Gammasphere. 9�105 alpha coincident events were recorded. In coincidence with LCP, the ?-? matrix was analyzed. We obtained the relative yields of fission fragment pairs as a function of the neutron number. In the Ba-?-Zr and Mo-?-Xe splits, the 6n-10n channels show ...

As has been reported from Orsay (France), superheavy transactinides with a subsequent alpha decay are discovered in technical oxide of Hf. In this case spontaneous fission is a competitive or basic process for some isotopes in the chain. According to the ...

... THERMODYNAMIC PROPERTIES OF TERNARY Rlt?'RAC- i ... THERMODYNAMIC PROPERTIES OF TERNARY REFRACTORY CARBIDES ...

Binary asteroid systems comprise 16% of the Near-Earth asteroid (NEA) population. A proposed mechanism for creating these systems is rotational fission, observational evidence for which is being reported at this meeting (Scheeres, Pravec, et al.). We have developed a detailed simulation of this process to mimic the evolution of rubble pile asteroids spun to ...

Prompt {gamma}-{gamma}-{gamma} coincidence studies following spontaneous fission of {sup 252}Cf were carried out at Gammasphere first with 36 and later with 72 Ge detectors. Yields and neutron multiplicities were measured directly for Sr-Nd, Zr-Ce Mo-Ba, Ru-Xe, and Pd-Te correlated pairs. A new hot fission mode was discovered going via only {sup ...

In the framework of the present thesis by comparison of the experimental measurement data obtained by means of the detector system DIOGENES with calculated trajectories possible scission-point configurations of the fissioning nucleus should be stated. Spe...

Fission of heavy nuclides is accompanied by the birth of neutron rich fragment nuclei born in highly excited states. Following emission of prompt neutrons and x-rays, these fragments are typically left with atomic numbers that are 3-4 units smaller than s...

Phagocytosis is essential for the elimination of pathogens and for clearance of apoptotic bodies. The ingestion process entails extensive remodeling of the cellular membranes, particularly when large and/or multiple particles are engulfed. The membrane fusion and fission events that accompany phagocytosis are described. The coordinated sequence of membrane ...

High energy bremsstrahlung emission during spontaneous fission of 252Cf is observed. The new experimental method to detect rare coincident events by digital storage oscilloscope is used. The ?-rays with energies up to 60 MeV have been measured (by a BGO detector) in coincidence with neutrons detected by a plastic scintillator. The determination of ?-ray emission probability up ...

Reported is work for the period indicated under the subject contract. Specific tasks covered in the report are: (1) A re-examination of fission product yield uncertainties to be used as imput to merging sensitivity calculations; (2) A tabulation of recommended uncertainties on fission product decay energies to accompany the decay ...

High energy photon emission accompanying the spontaneous fission of {sup 252}Cf is measured for different mass splits. The photon yields up to an energy of 20 MeV are obtained at several angles relative to the fission direction. Statistical model calculations are used to interpret the data. The photon yield is found to be very ...

High energy photon emission accompanying the spontaneous fission of 252Cf is measured for different mass splits. The photon yields up to an energy of 20 MeV are obtained at several angles relative to the fission direction. Statistical model calculations are used to interpret the data. The photon yield is found to be very sensitive to ...

We discuss a new surface-plus-window mechanism for the conversion of nuclear collective energy into internal degrees of freedom at intermediate excitation energies. This novel dissipation mechanism, which results from the long mean free path of nucleons inside a nucleus, involves interactions of either one or two nucleons with the moving nuclear surface and also, for dumbbell-like shapes ...

Spontaneous fission of uranium in minerals creates a damaged "track" along the trajectory of the fission fragments. Fission tracks in fluorapatite, enlarged by chemical etching, are widely used in geologic age-dating and the reconstruction of the thermal history of Earth's crust. However, despite this wide spread application, there ...

The neutron emission probabilities for long-range alpha (LRA), helium-3, triton and proton-accompanied fission of SVSCf are measured in a three-parameter experiment in which a liquid scintillation detector and a telescope are used to record the number of prompt neutrons and the energy of light charged particles. The average numbers of neutrons per ...

The purpose of this booklet is to provide a basic understanding of nuclear fission energy and different fission reaction concepts. Topics discussed are: energy use and production, current uses of fuels, oil and gas consumption, alternative energy sources, fossil fuel plants, nuclear plants, boiling water and pressurized water reactors, the light water ...

Two energy spectra of the neutrons emitted in the spontaneous fission process of /sup 252/Cf were measured in the neutron energy range between 0.15 and 15 MeV using nanosecond time-of-flight technique. In the first experiment the gamma -rays accompanying the fission process were used to generate the time zero signals and in ...

The spontaneous fission fragments from /sup 244/Cm were counted on a xenon scintillation detector, whose walls were covered with a layer of sodium salicylate to convert the ultraviolet emission of xenon to visible light. Long- range alpha particles were counted on a CsI crystal 0.8 mm thick. The /sup 244/ Cm was purified from rare earths by elution from a Dowex-50 ...

Prompt ?-?-? and x-?-? coincidence studies following the spontaneous fission of 252Cf were carried out first at Oak Ridge then at Gammasphere first with 36 and later with 72 Ge and two x-ray detectors and a long x-ray-? coincidence experiment at Idaho. Many new cases of correlated pairs in cold (zero neutron emission) binary fission are observed and for ...

How organisms allocate limited resources to reproduction is critical to their fitness. The size and number of offspring produced have been the focus of many studies. Offspring size affects survival and growth and determines offspring number in the many species where there is a trade-off between size and number. Many social insects reproduce by colony fission, whereby young ...

A small shift of an angular distribution of prompt ?-rays relative to the fission axis of 236U* 235U(n,?f) process is presented. This effect has been observed in the experiment at BER-II reactor of BENSC/HMI (Berlin). The sign of the shift depends on the direction of the incident neutron beam polarization. This phenomena can be explained by the rotation of fissile nucleus ...

This study was motivated by reports of the observation of ternary events in Kr- and Xe-induced reactions corresponding to the fast fission, or splitting, of projectile like products. The first of these reports, by Olmi et al., emphasized indirect evidence obtained from inclusive data from the reaction /sup 86/Kr + /sup 166/Er at 12.1 MeV/u. It was argued ...

Energy distributions and yields of ternary particles (TP's) emitted in the thermal neutron induced fission of 229Th, 233U and 239Pu have been determined. Special emphasis was put on the study of heavy ternary particles. The measurements were performed at the high flux reactor of the Institut Laue-Langevin (ILL). For identification of ...

Binary and ternary cluster decay of 60Zn compound nuclei at high angular momentum, formed in the 36Ar + 24Mg reaction at E lab(36Ar) = 195 MeV, has been measured in a unique kinematic coincidence setup consisting of two large area position sensitive (x, y) gas detector telescopes with Bragg-ionization chambers (BRS). The BRS provides the opportunity to measure the reaction ...