Description of fusion and evaporation residue formation cross sections in reactions leading to the formation of elementZ=122within the Langevin approach

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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Evaporation residue cross-sections as a probe for nuclear dissipation in the fission channel of a hot rotating nucleus

The European Physical Journal A ◽

10.1140/epja/i2003-10038-x ◽

2003 ◽

Vol 18 (1) ◽

pp. 9-15 ◽

Cited By ~ 22

Author(s):

Gargi Chaudhuri ◽

Santanu Pal

Keyword(s):

Cross Sections ◽

Evaporation Residue ◽

Nuclear Dissipation

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Evaporation residue cross sections and average neutron multiplicities in the 64Ni+92Zr and 12C+144Sm reactions leading to 156Er

Physics Letters B ◽

10.1016/0370-2693(86)91245-1 ◽

1986 ◽

Vol 181 (1-2) ◽

pp. 16-20 ◽

Cited By ~ 36

Author(s):

R.V.F. Janssens ◽

R. Holzmann ◽

W. Henning ◽

T.L. Khoo ◽

K.T. Lesko ◽

...

Keyword(s):

Cross Sections ◽

Evaporation Residue ◽

Neutron Multiplicities ◽

Average Neutron

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MEASURING CAPTURE CROSS SECTIONS FOR HEAVY-ELEMENT PRODUCTION

International Journal of Modern Physics E ◽

10.1142/s0218301304002077 ◽

2004 ◽

Vol 13 (01) ◽

pp. 293-300

Author(s):

NEIL ROWLEY ◽

NABILA GRAR

Keyword(s):

Cross Section ◽

Compound Nucleus ◽

Cross Sections ◽

Reaction Path ◽

Superheavy Element ◽

Evaporation Residue ◽

Capture Cross ◽

Total Capture ◽

Capture Cross Sections

The creation of the nucleus of a superheavy element follows an extremely complex reaction path starting with the crossing of an external potential barrier (or distribution of barriers). This is followed by the evolution towards an equilibrated compound nucleus, which takes place in competition with pre-compound-nucleus fission (quasi-fission). Once formed the equilibrated compound nucleus must still survive against true fusion to yield a relatively long-lived evaporation residue. Much of this path is poorly understood, though recently, progress has been made on the role of the entrance-channel in quasi-fission. This will be briefly reported and a method proposed to measure the total capture cross section for such systems directly.

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COMPARISON OF THE FUSION-FISSION AND QUASIFISSION MECHANISMS IN HEAVY-ION COLLISIONS

International Journal of Modern Physics E ◽

10.1142/s021830130901294x ◽

2009 ◽

Vol 18 (04) ◽

pp. 841-849 ◽

Cited By ~ 5

Author(s):

AVAZBEK NASIROV ◽

GIOVANNI FAZIO ◽

GIORGIO GIARDINA ◽

GIUSEPPE MANDAGLIO ◽

MARINA MANGANARO ◽

...

Keyword(s):

Cross Sections ◽

Theoretical Method ◽

Heavy Ion ◽

Evaporation Residue ◽

System Model ◽

Complete Fusion ◽

Dinuclear System ◽

Ion Collisions ◽

Partial Fusion ◽

Evaporation Residues

The decrease of the evaporation residue yields in reactions with massive nuclei is explained by an increase of the competition between quasifission and complete fusion processes and by the decrease of the survival probability of the heated and rotating nuclei against fission along the de-excitation cascade of the compound nucleus. The experimental data on the yields of evaporation residue, fusion-fission and quasifission fragments in the 48 Ca + 154 Sm reaction are analyzed in the framework of the combined theoretical method based on the dinuclear system concept and advanced statistical model. The measured yields of evaporation residues of the 48 Ca + 154 Sm reaction have been well reproduced and yields of fission fragments were analyzed using the partial fusion and quasifission cross sections calculated in the dinuclear system model. Such a way of calculation is used to find optimal conditions for the synthesis of the new element Z = 120 (A = 302) by studying the excitation functions of evaporation residues of the 54 Cr + 248 Cm , 58 Fe + 244 Pu , and 64 Ni + 238 U reactions. Our estimations show that the 54 Cr + 248 Cm reaction is preferable in comparison with the two others.

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LANGEVIN DESCRIPTION OF THE EVAPORATION RESIDUE SPIN DISTRIBUTION

International Journal of Modern Physics E ◽

10.1142/s0218301308010854 ◽

2008 ◽

Vol 17 (09) ◽

pp. 1875-1882 ◽

Cited By ~ 1

Author(s):

WEI YE ◽

HONG-WEI YANG ◽

FENG WU

Keyword(s):

Theoretical Calculations ◽

Accurate Determination ◽

Viscosity Coefficient ◽

Evaporation Residue ◽

Langevin Equations ◽

Compound System ◽

Spin Distribution ◽

Langevin Approach ◽

Evaporation Residue Cross Section

The recently measured spin distribution of evaporation residue cross section in the reaction 16 O + 184 W is studied in the framework of Langevin equations. Results show that the Langevin approach can describe this observable very well. Moreover, a pre-saddle nuclear viscosity coefficient of 5 × 1021 s-1 is extracted by comparing theoretical calculations with experimental data. We also explore the effect of the isospin of a system on the spin distribution by evaluating the evaporation residue spin distribution of nuclei 194 Pb , 200 Pb and 206 Pb . It has been found that with increasing the isospin of the system, the sensitivity of the evaporation residue spin distribution to the nuclear viscosity is decreased significantly. This result suggests that choosing a low-isospin compound system favors an accurate determination of pre-saddle dissipation strength.

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