The 93Nb(n, 2n)92Nb cross-section at 14 MeV extracted from experimental neutron emission spectrum

By using semiclassical method and considering Woods–Saxon and Coulomb potentials, the level density parameter a was calculated for three superheavy nuclei 270110, 278112 and 290116. Obtained results showed that the value of level density parameter of these nuclei is near to the simple relation a ≈ A/10. In framework of the dinuclear system model, the effects of level density parameter on the probability of the formation of a compound nucleus, the ratio of neutron emission width and fission width, and evaporation residue cross-section of three cold fusion reactions 62 Ni +208 Pb , 70 Zn +208 Pb and 82 Se +208 Pb , leading to superheavy elements were investigated. The findings indicate that the level density parameter play a significant role in calculations of heavy-ion fusion–fission reactions. The obtained results in the case of a = A/12 have larger values in comparison with calculated level density parameter with Woods–Saxon potential (a WS ) and a = A/10. The theoretical results of the evaporation residue cross-section are very sensitive to the choice of level density parameter. The calculated values with a WS are in good agreement with experimental values.

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Photoneutron Cross Sections in 14N

Canadian Journal of Physics ◽

10.1139/p72-229 ◽

1972 ◽

Vol 50 (15) ◽

pp. 1689-1696 ◽

Cited By ~ 16

Author(s):

R. W. Gellie ◽

K. H. Lokan ◽

N. K. Sherman ◽

R. G. Johnson ◽

J. I. Lodge

Keyword(s):

Excited States ◽

Cross Section ◽

Cross Sections ◽

Neutron Emission ◽

Giant Resonance ◽

Sequential Decay ◽

Dipole Resonance ◽

Intermediate States ◽

Integrated Cross Section ◽

High Degree

Photoneutron distributions from 14N have been obtained by time-of-flight methods, for bremsstrahlung end-point energies increasing in 2 MeV steps from 15.5 to 29.5 MeV. A large part of the neutron yield is associated with the sequential decay of 14N to 12C, through well-defined intermediate states of 13C, at 7.55, 8.86, and 11.80 MeV, which are unstable against neutron emission. The (γ,n0) cross section for neutron emission to the ground state of 13N is found to agree very closely with the corresponding (γ,p0) cross section, implying a high degree of isospin purity for the giant dipole resonance of 14N. It is observed that the decay of the giant resonance proceeds freely through those odd-parity excited states of the A = 13 nuclei which are single hole states formed by the removal of a p-shell nucleon from the parent 14N.The integrated cross section for all neutron-producing interactions is found to be 88 ± 5 MeV mb.

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Anisotropic Neutron Emission Spectrum and Its Utilization for Verification of Nuclear Elastic Scattering Effect in Proton-Beam-Injected Deuterium Plasmas

IEEE Transactions on Plasma Science ◽

10.1109/tps.2018.2826546 ◽

2018 ◽

Vol 46 (6) ◽

pp. 2301-2306

Author(s):

Hideaki Matsuura ◽

Yasuko Kawamoto ◽

Shota Sugiyama ◽

Shogo Kajimoto

Keyword(s):

Elastic Scattering ◽

Emission Spectrum ◽

Proton Beam ◽

Neutron Emission ◽

Scattering Effect

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Experiments with neutron induced neutron emission from U-235, Pu-239, and graphite

EPJ Web of Conferences ◽

10.1051/epjconf/202023901004 ◽

2020 ◽

Vol 239 ◽

pp. 01004

Author(s):

Yaron Danon ◽

Ezekiel Blain ◽

Kumar Mohindroo ◽

Matt Devlin ◽

Keegan J.Kelly ◽

...

Keyword(s):

Cross Section ◽

Neutron Beam ◽

Neutron Emission ◽

National Laboratory ◽

Neutron Cross Section ◽

Science Center ◽

Neutron Detectors ◽

Los Alamos ◽

Los Alamos National Laboratory ◽

Neutron Time

A neutron induced neutron emission experiment was conducted as the Los Alamos Neutron Science Center (LANSCE) facility at Los Alamos National Laboratory (LANL). In this experiment, a sample was placed in a well collimated neutron beam and was surrounded by an array of 28 fast neutron detectors (EJ-309). The experiment was performed with a neutron flight path of 21.5 m from the source to the sample, and 1 m from the sample to the detectors. The neutron emission from the sample was measured as a function of neutron time of flight covering an incident energy range from 0.7- 20 MeV. The samples included U-235, Pu-239, carbon (graphite), and blanks that matched the encapsulation of the sample. The measured samples were constantly cycled in and out of the neutron beam. This type of experiment measures neutron emission from all reactions occurring in the sample such as fission and elastic and inelastic scattering. Similar to the methodology previously developed at RPI [1], the measurements were compared with detailed simulations of the experiment using different cross section evaluations for the sample. The observed differences can be attributed to the evaluated neutron cross section and angular distributions. The carbon sample was used as a reference to validate both the experiment and simulation methodology and showed good agreement between experiments and simulations. A review of the experimental setup, analysis methods, and some of the results will be presented.

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The Dominance of Proton/Neutron Evaporation Exit-Channel in a Fusion-Evaporation Reaction: The Effect of Target Nuclear Ratio (N/Z)

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.f3732.049620 ◽

2020 ◽

Vol 9 (6) ◽

pp. 456-457

Keyword(s):

Cross Section ◽

Neutron Emission ◽

Target Material ◽

Evaporation Residue ◽

Proton Emission ◽

Statistical Model Calculation ◽

Evaporation Reaction ◽

Neutron Evaporation ◽

Calculation Code ◽

Fusion Evaporation Reaction

Cross section of different evaporation residue have been calculated in 112Sn+16O (Neuron/Proton (N/Z) of the 112Sn target is 1.24) and124Sn+16O reaction (N/Z of the 124Sn is 1.48) with beam energy of 80 MeV using statistical model calculation code PACE4. These calculations predicts that the proton emission channels are predicted to be dominant when the N/Z ratio is small (i.e in the first reaction) whereas the neutron emission outgoing channels dominant in the second reaction when N/Z is large. Experimental phenomenon also revealed the fact that in order to populate the proton or neutron reach nucleus we have to choose the target material accordingly.

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