Excitation energy and nuclear dissipation probed with evaporation-residue cross sections

LL, Lα, Lβ, and Lγ X-ray fluorescence cross sections for Pr, Sm, Gd, Dy, Ho, Er, Yb, Pt Au, and Pb were measured at the excitation energy 16.58 keV. An X-ray tube and a secondary excitor system was used instead of radioisotopes for the measurements. Experimental cross sections are compared with the theoretical estimates based on relativistic Dirac–Hartree–Slater theory. Average L-shell fluorescence yields [Formula: see text] are deduced using the present experimental cross sections and the theoretical subshell photoionization cross sections. The derived average fluorescence yields are fitted by least squares to polynomials in Z of the form ΣnanZn and compared with theoretical and earlier fitted values. Good agreement is observed ' between the experimental results and the theoretical estimates based on relativistic Dirac–Hartree–Slater theory.

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On Z=2 Projectile Fragments Emitted in the Interactions of 3.7A GeV 28Si in Nuclear Emulsions

International Journal of Modern Physics E ◽

10.1142/s0218301398000142 ◽

1998 ◽

Vol 07 (03) ◽

pp. 341-355 ◽

Cited By ~ 4

Author(s):

B. K. Singh ◽

S. K. Tuli

Keyword(s):

Excitation Energy ◽

Cross Sections ◽

Mass Number ◽

Multiplicity Distribution ◽

Production Cross ◽

Emission Angle ◽

Single Source ◽

Momentum Spread ◽

Nuclear Emulsions ◽

Scaling Behaviour

We report the results on partial production cross sections for Z=2 projectile fragments emitted in 28Si-emulsion interactions at 3.7 A GeV. Scaling behaviour of the multiplicity distribution of Z=2 PFs has been checked. The emission angle of Z=2 PFs has been measured and pseudorapidity distributions for these PFs have been obtained. We observe that the value of momentum spread σ(p) for Z=2 PFs grows with increasing mass number of the projectile. The emission of Z=2 PFs is consistent with a single source with an excitation energy of about 8.9 MeV. The data has been compared with available data reported for lighter as well as heavier projectiles at the same and/or different energies.

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Robustness of the excitation energy at scission as a novel probe of nuclear dissipation at high energy

Physical Review C ◽

10.1103/physrevc.86.034605 ◽

2012 ◽

Vol 86 (3) ◽

Cited By ~ 12

Author(s):

W. Ye ◽

N. Wang

Keyword(s):

Excitation Energy ◽

High Energy ◽

Nuclear Dissipation

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Inference on ﬁssion timescale from neutron multiplicity measurement in18O+184W

Journal of Physics G Nuclear and Particle Physics ◽

10.1088/1361-6471/ac4b3f ◽

2022 ◽

Author(s):

Niraj Kumar Rai ◽

Aman Gandhi ◽

M T Senthil Kannan ◽

Sujan Kumar Roy ◽

Saneesh Nedumbally ◽

...

Keyword(s):

Excitation Energy ◽

Beam Energy ◽

Incident Beam ◽

Fission Process ◽

Incident Beam Energy ◽

Neutron Evaporation ◽

Neutron Multiplicities ◽

Nuclear Dissipation ◽

Fission Yields ◽

Primary Compound

Abstract The pre-scission and post-scission neutron multiplicities are measured for the 18O + 184W reaction in the excitation energy range of 67.23−76.37 MeV. Langevin dynamical calculations are performed to infer the energy dependence of fission decay time in compliance with the measured neutron multiplicities. Different models for nuclear dissipation are employed for this purpose. Fission process is usually expected to be faster at a higher beam energy. However, we found an enhancement in the average fission time as the incident beam energy increases. It happens because a higher excitation energy helps more neutrons to evaporate that eventually stabilizes the system against fission. The competition between fission and neutron evaporation delicately depends on the available excitation energy and it is explained here with the help of the partial fission yields contributed by the different isotopes of the primary compound nucleus.

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Investigation of the synthesis of the unknown superheavy nuclei 309,312126

International Journal of Modern Physics E ◽

10.1142/s0218301319500563 ◽

2019 ◽

Vol 28 (07) ◽

pp. 1950056 ◽

Cited By ~ 3

Author(s):

T. V. Nhan Hao ◽

N. N. Duy ◽

K. Y. Chae ◽

N. Quang Hung ◽

N. Nhu Le

Keyword(s):

Cross Section ◽

Cross Sections ◽

Charge Asymmetry ◽

Evaporation Residue ◽

Fission Process ◽

Dinuclear System ◽

Mass Asymmetry ◽

Interacting Systems ◽

First Time ◽

Text Element

In this paper, we applied the method developed by Santhosh and Safoora in [Phys. Rev. C 94 (2016) 024623; 95 (2017) 064611] to theoretically investigate the fusion, evaporation-residue (ER) and fission cross-sections of the synthesis of the unknown superheavy [Formula: see text]126 nuclei produced by using the [Formula: see text]Ni + [Formula: see text]Cf and [Formula: see text]Zn + [Formula: see text]Cm combinations. The charge asymmetry, mass asymmetry and fissility of the DiNuclear System (DNS) in the synthesis of the mentioned combinations are also estimated. The calculated results show that the ER cross-sections for the synthesis of the [Formula: see text]126 nuclei are predicted to be much less than 1.0[Formula: see text]fb. In particular, it has been found that there may exist a valley of the ER cross-sections in the synthesis of a superheavy [Formula: see text] element, which produces the [Formula: see text]126 isotope. Subsequently, a model for the mass dependence of the ER cross-section in the synthesis of the [Formula: see text]126 isotopes has been proposed for the first time. On the other hand, the quasi-fission process strongly dominates over the fusion in the two concerned interacting systems. The present results, together with those reported in the previous studies, indicate that the investigated projectile–target combinations are not capable for the synthesis of the [Formula: see text]126 isotopes due to tiny fusion cross-sections (about 2–3[Formula: see text]zb), which go beyond the limitations of available facilities. Further studies are thus recommended to search for alternative interacting systems. In conclusion, this work provides useful information for the synthesis of the gap isotopes [Formula: see text]126, which have not been well studied up to date.

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