28.—Simultaneous Emission of two Light Charged Particles in Fission

SynopsisThe suggestion is made that in certain cases the light particles emitted in ternary fission may be released otherwise than in the ground state—and, in particular, that low-lying particle-unstable states may be involved. This suggestion is examined quantitatively in respect of the release of 8Be in the first excited short-lived state of 2·9 MeV excitation, and is shown to provide a satisfactory interpretation of the observation of quaternary fission in the α,α mode recently reported by Kataria et al. (1973). It appears probable that the other modes of quaternary fission observed by these authors should be similarly interpreted.

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Dependence of light charged particles parameters on Z2/A in ternary fission

Zeitschrift für Physik A Hadrons and Nuclei ◽

10.1007/bf02769705 ◽

1996 ◽

Vol 355 (1) ◽

pp. 341-342

Author(s):

M. P. Ivanov ◽

I. David ◽

A. S. Fomichev ◽

S. M. Lukyanov ◽

Yu. E. Penionzhkevich ◽

...

Keyword(s):

Charged Particles ◽

Ternary Fission ◽

Light Charged Particles

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Dependence of the ROT effect on the energy of different light charged particles and on the incident neutron energy

EPJ Web of Conferences ◽

10.1051/epjconf/202125600006 ◽

2021 ◽

Vol 256 ◽

pp. 00006

Author(s):

Irina Guseva ◽

Alexei Gagarski ◽

Friedrich Gönnenwein ◽

Yuri Gusev

Keyword(s):

Angular Distribution ◽

Angular Velocity ◽

Compound Nucleus ◽

Charged Particles ◽

Ternary Fission ◽

Incident Neutron ◽

Incident Neutron Energy ◽

Trajectory Calculations ◽

The Moment ◽

Light Charged Particles

The shift of the angular distribution of different light charged particles in ternary fission of 235U induced by polarized neutrons, the so-called ROT effect, was estimated by modified trajectory calculations, which take into account the rotation of the compound nucleus. In previous publications only α-particles were considered. It is shown here that inclusion of tritons significantly improves the agreement of the energy dependence of the ROT effect with experiment while the inclusion of 5He particles practically does not influence this dependence. In particular, the change in the magnitude of the ROT effect depending on the energy of incident neutrons is correctly predicted. Also, the ROT effect for gamma quanta and neutrons in binary fission is discussed along the same lines, because all mentioned effects are proportional to the effective angular velocity of the compound nucleus at the moment of scission.

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Attempts to detect the emission of secondary charged particles in the fission of 235 U by slow neutrons

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1947.0125 ◽

1947 ◽

Vol 191 (1027) ◽

pp. 428-441 ◽

Cited By ~ 11

Keyword(s):

Thin Film ◽

Charged Particle ◽

Uranium Oxide ◽

Charged Particles ◽

The Other ◽

Light Charged Particle ◽

Fission Fragments ◽

The Mean ◽

Light Charged Particles ◽

Α Particles

If light charged particles (protons, α-particles, etc.) are emitted during fission, it should be possible to establish this fact by a simple coincidence experiment. Suppose two detectors are arranged so that they can both ‘see’ a thin film of uranium oxide. Let one of the detectors register the entry of fission fragments only, say at the rate of F (sec. -1 ). Let the other detector register not only fission fragments (unless they are excluded by an interposed absorber) but also light charged particles (protons, a-particles, etc.) with energies within certain limits. Suppose that the rate of registration in the second detector is P (sec. -1 ), that the mean efficiency for the detection of a light charged particle emitted from the uranium film is e , and that the average number of light charged particles liberated per fission is η.

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The emission of light charged particles in the slow neutron fission of uranium

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1948.0022 ◽

1948 ◽

Vol 241 (833) ◽

pp. 323-343 ◽

Cited By ~ 18

Keyword(s):

Long Range ◽

Fission Fragment ◽

Short Range ◽

Photographic Plate ◽

Charged Particles ◽

Slow Neutron ◽

Neutron Fission ◽

Green Is ◽

Light Particles ◽

Light Charged Particles

This paper describes the extension of the photographic plate technique to the recording of fission fragment tracks and the application of this method to the study of rare modes of fission in the case of the slow neutron fission of uranium. The emission of a short-range group of light particles in the fission of U 235 , reported by Cassels, Dainty, Feather & Green, is confirmed and the angular and range distributions of these particles described. In addition, the emission of long-range light particles with ranges up to 45 cm. of air is described. The abundance of this mode of fission is 1 in 340 + 40 fission events. The angular and range distributions of these long-range particles are given.

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Dependence of light charged particles parameters on Z2/A in ternary fission

Zeitschrift für Physik A Hadrons and Nuclei ◽

10.1007/s002180050119 ◽

1996 ◽

Vol 355 (4) ◽

pp. 341-342 ◽

Cited By ~ 2

Author(s):

M. P. Ivanov ◽

I. David ◽

A. S. Fomichev ◽

S. M. Lukyanov ◽

Yu. E. Penionzhkevich ◽

...

Keyword(s):

Charged Particles ◽

Ternary Fission ◽

Light Charged Particles

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ON THE EMISSION OF HEAVY CLUSTERS FROM MEDIUM MASS COMPOUND NUCLEUS

International Journal of Modern Physics E ◽

10.1142/s021830131101926x ◽

2011 ◽

Vol 20 (04) ◽

pp. 1054-1057

Author(s):

◽

G. ADEMARD ◽

J.P. WIELECZKO ◽

E. BONNET ◽

A. CHBIHI ◽

...

Keyword(s):

Atomic Number ◽

Compound Nucleus ◽

Cross Sections ◽

Incident Energy ◽

Charged Particles ◽

Binary Fission ◽

Medium Mass ◽

Light Particles ◽

The Cross ◽

Light Charged Particles

Fragments with atomic number 6≤ Z ≤28 were measured in singles and in coincidence with emitted light charged particles in the 78 Kr +40 Ca reactions at 5.5 AMeV incident energy by means of the 4π-INDRA array at GANIL. Kinematical features of the fragments are compatible with a binary fission from compound nucleus. The cross-sections σZ indicate the coexistence of macroscopic behaviour and structure effects. Fragment-particle coincidences show that fragments with Z ≤12 are excited below the separation energies of light particles.

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Preformation probability of light charged particles emitted equatorially in ternary fission of Cf252

Physical Review C ◽

10.1103/physrevc.104.014616 ◽

2021 ◽

Vol 104 (1) ◽

Author(s):

W. M. Seif ◽

A. S. Hashem

Keyword(s):

Charged Particles ◽

Ternary Fission ◽

Light Charged Particles

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Ground state and stability of the fractional plateau phase in metallic Shastry–Sutherland system TmB4

Scientific Reports ◽

10.1038/s41598-021-86353-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Matúš Orendáč ◽

Slavomír Gabáni ◽

Pavol Farkašovský ◽

Emil Gažo ◽

Jozef Kačmarčík ◽

...

Keyword(s):

Magnetic Field ◽

Phase Diagram ◽

Ground State ◽

Constant Magnetic Field ◽

Paramagnetic Phase ◽

The Other ◽

Zero Field ◽

Plateau Phase ◽

Low Field ◽

Zero Field Cooling

AbstractWe present a study of the ground state and stability of the fractional plateau phase (FPP) with M/Msat = 1/8 in the metallic Shastry–Sutherland system TmB4. Magnetization (M) measurements show that the FPP states are thermodynamically stable when the sample is cooled in constant magnetic field from the paramagnetic phase to the ordered one at 2 K. On the other hand, after zero-field cooling and subsequent magnetization these states appear to be of dynamic origin. In this case the FPP states are closely associated with the half plateau phase (HPP, M/Msat = ½), mediate the HPP to the low-field antiferromagnetic (AF) phase and depend on the thermodynamic history. Thus, in the same place of the phase diagram both, the stable and the metastable (dynamic) fractional plateau (FP) states, can be observed, depending on the way they are reached. In case of metastable FP states thermodynamic paths are identified that lead to very flat fractional plateaus in the FPP. Moreover, with a further decrease of magnetic field also the low-field AF phase becomes influenced and exhibits a plateau of the order of 1/1000 Msat.

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