Theoretical Study on the Formation of 1-neutron and 2-neutron Halo Nuclei via Decay of Elements in Super-Heavy Region

The possibility for the existence of 1-neutron and 2-neutron halo nuclei through the decay of even-even nuclei 270-316116, 272-318118 and 278-320120 in the super-heavy region is studied within the frame work of the Coulomb and Proximity Potential Model (CPPM). Halo structure in neutron rich nuclei with Z<=20 is identified by calculating the neutron separation energies and on the basis of potential energy considerations. The 1n + core configuration of proposed 1-neutron halo nuclei between z=10 and Z=20 is found shifted to 2n + core configuration in higher angular momentum states. The calculation of half-life of decay is performed by considering the proposed halo nuclei as spherical cluster and as deformed nuclei with a rms radius. Except for 15C, the half-life of decay is found decreased when the rms radius is considered. Only the 1-neutron halo nuclei 26F and 55Ca showed half-lives of decay which are less than the experimental limit. None of the proposed 2-neutron halo nuclei have shown a half-life of decay lower than the experimental limit. Also, the probability for the emission of neutron halo nuclei is found to be less in super-heavy region when compared with the clusters of same isotope family. Further, neutron shell closure at neutron numbers 150, 164 and 184 is identified form the plot of log10 T1/2 verses the neutron number of parents. The plots of Q-1/2 verses log10 T1/2 and -ln P verses log10 T1/2 for various halo nuclei emitted from the super-heavy elements are found to be linear showing that Geiger-Nuttall law is applicable to the emission of neutron halo also.

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A Systematic Study on the Existence of 7-9B, 16-19Ne, 8-11C, 23-30P and 26-32S Nuclei via Cluster Decay in the Super Heavy Region

Journal of Nuclear Physics Material Sciences Radiation and Applications ◽

10.15415/jnp.2019.71001 ◽

2019 ◽

Vol 7 (1) ◽

pp. 1-12

Author(s):

K. P. Anjali ◽

K. Prathapan ◽

R. K. Biju ◽

K. P. Santhosh

Keyword(s):

Half Life ◽

Potential Model ◽

Neutron Number ◽

Exotic Nuclei ◽

Cluster Decay ◽

Shell Closure ◽

Proximity Potential ◽

Deformed Nuclei ◽

C 23 ◽

Spherical Nuclei

Based on the Coulomb and Proximity Potential Model, we have studied the decay probabilities of various exotic nuclei from even-even nuclei in the super heavy region. The half-lives and barrier penetrability for the decay of exotic nuclei such as 7-9B, 16-19 Ne, 8-11 C, 23-30 P and 26-32 S from the isotopes 274-332116,274-334 118 and 288-334120 are determined by considering them as spherical as well as deformed nuclei. The effect of ground state quadrupole (β2), Octupole (β3) and hexadecapole (β4) deformation of parent, daughter and cluster nuclei on half- lives and barrier penetrability were studied. Calculations have done for the spherical nuclei and deformed nuclei in order to present the effects of the deformations on half-lives. It is found that height and shape of the barrier reduces by the inclusion of deformation and hence half-life for the emission of different clusters decreases and barrierpenetrability increases. Changes in the half-lives with and without the inclusion of deformation effects are compared in the graph of half -life and barrier penetrability against neutron number of parents. It is evident from the computed half lives that many of the exotic nuclei emissions are probable. Moreover shell structure effects on the half-lives of decay are evident from these plots. Peak in the plot of halflife and dip in the plot of barrier penetrability against neutron number of parent show shell closure at or near to N=184, N=200 and N=212.

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ALPHA-DECAY STUDIES ON 130-153Eu NUCLEI

International Journal of Modern Physics E ◽

10.1142/s021830131350081x ◽

2013 ◽

Vol 22 (11) ◽

pp. 1350081 ◽

Cited By ~ 14

Author(s):

K. P. SANTHOSH ◽

B. PRIYANKA

Keyword(s):

Experimental Data ◽

Potential Model ◽

Alpha Decay ◽

Shell Closure ◽

Proximity Potential ◽

Deformed Nuclei ◽

Neutron Shell ◽

Good Agreement ◽

Neutron Shell Closure

The alpha-decay half-lives of the 24 isotopes of Eu (Z = 63) nuclei in the region 130≤A≤153, have been studied systematically within the Coulomb and proximity potential model (CPPM). We have modified the assault frequency and re-determined the half-lives and they show a better agreement with the experimental value. We have also done calculations on the half-lives within the recently proposed Coulomb and proximity potential model for deformed nuclei (CPPMDN). The computed half-lives are compared with the experimental data and they are in good agreement. Using our model, we could also demonstrate the influence of the neutron shell closure at N = 82, in both parent and daughter nuclei, on the alpha-decay half-lives.

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Alpha-decay half-lives of polonium isotopes in the mass range of 186–218

International Journal of Modern Physics E ◽

10.1142/s0218301319500435 ◽

2019 ◽

Vol 28 (06) ◽

pp. 1950043 ◽

Cited By ~ 1

Author(s):

S. S. Hosseini ◽

H. Hassanabadi ◽

Dashty T. Akrawy ◽

S. Zarrinkamar

Keyword(s):

Experimental Data ◽

Half Life ◽

Potential Model ◽

Alpha Decay ◽

Mass Range ◽

Shell Closure ◽

Proximity Potential ◽

Neutron Shell ◽

Neutron Shell Closure

The [Formula: see text]-decay (AD) half-life (HL) of [Formula: see text]Po [Formula: see text] isotopes is studied systematically within the modified Coulomb and proximity potential model (MCPPM). The computed HLs are compared with the existing theoretical formulae including Royer, AKRE, Ren B and MRen B. This study considers the role of neutron shell closure [Formula: see text] on the AD HLs. The comparison with the experimental data indicates the acceptability of the results.

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Probable cluster decays from 270–318118 superheavy nuclei

International Journal of Modern Physics E ◽

10.1142/s0218301314500591 ◽

2014 ◽

Vol 23 (10) ◽

pp. 1450059 ◽

Cited By ~ 8

Author(s):

K. P. Santhosh ◽

B. Priyanka

Keyword(s):

Half Life ◽

Potential Model ◽

Scaling Law ◽

Alpha Decay ◽

Neutron Number ◽

Cluster Decay ◽

Superheavy Nuclei ◽

Proximity Potential ◽

Universal Formula ◽

Good Agreement

The cluster decay process in 270–318118 superheavy nuclei has been studied extensively within the Coulomb and proximity potential model (CPPM), thereby investigating the probable cluster decays from the various isotopes of Z = 118. On comparing the predicted decay half-lives with the values evaluated using the Universal formula for cluster decay (UNIV) of Poenaru et al., the Universal Decay Law (UDL) of Qi et al., and the Scaling Law of Horoi et al., it was seen that, our values matches well with these theoretical values. A comparison of the predicted alpha decay half-life of the experimentally synthesized superheavy isotope 294118 with its corresponding experimental value shows that, our theoretical value is in good agreement with the experimental value. The plots for log 10(T1/2) against the neutron number of the daughter in the corresponding decay reveals the behavior of the cluster half-lives with the neutron number of the daughter nuclei and for most of the decays, the half-life was found to be the minimum for the decay leading to a daughter with N = 184. Most of the predicted half-lives are well within the present experimental upper limit (1030 s) and lower limit (10-6 s) for measurements and hence these predictions may be of great use for further experimental investigation on cluster decay in the superheavy region.

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