Studies on heavy particle radioactivity from superheavy nuclei leading to doubly magic 304120 daughter nuclei

2017 ◽  
Vol 95 (1) ◽  
pp. 31-37 ◽  
Author(s):  
K.P. Santhosh ◽  
Indu Sukumaran

The alpha decay and heavy particle radioactivity of the isotopes of even–even superheavy nuclei with Z = 122–132 have been studied within Coulomb and proximity potential model. The predicted half-lives using our model are found to be in agreement with universal formula for cluster decay of Poenaru et al., the universal decay law of Qi et al., and the scaling law of Horoi et al., and most of the estimated values are well within the experimental upper limit (T1/2 < 1030 s). Our work targets the shell closure properties in the superheavy region. From the plots for log10(T1/2) against the neutron number of the daughter nuclei, three prominent minima are observed at N = 178, 184, and 194. The results show that in addition to N = 184, the neutron numbers N = 178 and 194 exhibit extra stability as compared to their neighbours. Based on these important observations, we have identified the possibility of N = 194 being a magic neutron number next to N = 184. Further, a new island of stability in the superheavy region has been predicted around the doubly magic 304120 superheavy nuclei and thus established the role of neutron shell closure in heavy particle decays very well.

2014 ◽  
Vol 23 (10) ◽  
pp. 1450059 ◽  
Author(s):  
K. P. Santhosh ◽  
B. Priyanka

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.


2017 ◽  
Vol 26 (03) ◽  
pp. 1750003 ◽  
Author(s):  
K. P. Santhosh ◽  
Indu Sukumaran

Within the framework of Coulomb and proximity potential model (CPPM), the probable heavy particle decays from various isotopes of superheavy nuclei (SHN), [Formula: see text], within the range [Formula: see text]–[Formula: see text] have been studied using two versions of proximity potential; proximity 1977 and proximity 2000. The decay half lives evaluated using proximity 2000 is observed to be higher than the values obtained using proximity 1977. The effect of surface deformation on the decay half lives is studied using Coulomb and proximity potential for deformed nuclei (CPPMDN). As a result of the inclusion of deformation [Formula: see text], the penetrability of the decays are observed to be increased and accordingly the decay half lives are reduced. The estimated values are compared with other theoretical models, Universal curve (UNIV), Universal Decay law (UDL) and the scaling law of Horoi. The odd–even staggering (OES) effect is observed in the emission of odd mass clusters. An intriguing aspect of the study is the effect of the magicity at [Formula: see text] which is confirmed from the plot of [Formula: see text] against the neutron number of the daughter nuclei. Almost all the predicted half lives are favorable for experimental measurements. The Geiger–Nuttall (GN) plots and the Universal curve have been studied for various cluster emissions from various superheavy isotopes with [Formula: see text]. Finally, the linearity of the GN plot and the Universal curve of the heavy particle emissions very well established the strength of CPPM.


2020 ◽  
Vol 29 (10) ◽  
pp. 2050087
Author(s):  
N. Sowmya ◽  
H. C. Manjunatha ◽  
P. S. Damodara Gupta

In this work, we have made an attempt to study the cluster-decay half-lives and alpha-decay half-lives of the superheavy nuclei [Formula: see text]Og by considering the temperature-dependent (TD) and also temperature-independent (TID) proximity potential model. The evaluated half-lives were compared with that of the experiments. To predict the decay modes, we have compared the cluster-decay half-lives and alpha-decay half-lives with that of spontaneous fission half-lives. This work also predicts the decay chains of the superheavy nuclei [Formula: see text]Og and finds an importance in the synthesis of further isotopes of superheavy element Oganesson.


2019 ◽  
Vol 28 (06) ◽  
pp. 1950043 ◽  
Author(s):  
S. S. Hosseini ◽  
H. Hassanabadi ◽  
Dashty T. Akrawy ◽  
S. Zarrinkamar

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.


2019 ◽  
Vol 28 (07) ◽  
pp. 1950051 ◽  
Author(s):  
G. Naveya ◽  
S. Santhosh Kumar ◽  
S. I. A. Philominraj ◽  
A. Stephen

The one-proton emission, alpha decay and cluster decay using a Cubic Plus Proximity model with improved transfer-matrix method are executed for the first time for the study of decay properties of 368 isotopes of nuclei, far from the beta stability line and beyond the islands of stability [Formula: see text] superheavy nuclei are studied within the range [Formula: see text]. The calculated decay half-lives are in good agreement with other theoretical approaches. The signature of neutron shell closure at [Formula: see text] and proton shell closure at [Formula: see text] obtained from half-life curves for emission of different clusters pronounces the previous predictions. Investigation of competition between various decay modes brings out the dominant decay mode associated with an isotope; for a given [Formula: see text] with increasing [Formula: see text] the dominant decay mode is seen to shift from proton decay to alpha decay and finally spontaneous fission. The decay modes and half-lives which are within the limit of experimental detection [Formula: see text] are presented.


Author(s):  
K. P. Anjali ◽  
K. Prathapan ◽  
R. K. Biju ◽  
K. P. Santhosh

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.


2013 ◽  
Vol 22 (11) ◽  
pp. 1350081 ◽  
Author(s):  
K. P. SANTHOSH ◽  
B. PRIYANKA

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.


2017 ◽  
Vol 26 (10) ◽  
pp. 1750069 ◽  
Author(s):  
S. S. Hosseini ◽  
H. Hassanabadi ◽  
H. Sobhani

The alpha decay half-lives of even–even and even–odd Platinum (Pt) nuclei have been studied within the Coulomb and proximity potential model (CPPM). The present study is restricted to even–even nuclei with [Formula: see text]–198. The results are compared with other calculations such as the Semi-empirical formula (SemFIS) from Poenaru et al. based on fission theory of alpha decay, the Viola–Seaborg (VS), Royer (R) and Brown formulae. Also, the alpha decay half-lives have been calculated using the Scaling law of Brown (SLB), the Universal Decay Law (UDL) of Qi et al., the Scaling Law of Horoi et al. (SLH), and Akrawy–Dorin formula (ADF) of Akrawy and Poenaru, which are the Royer modified formula for alpha decay half-live by adding asymmetry term.


2012 ◽  
Vol 90 (1) ◽  
pp. 53-60
Author(s):  
Arati Devi ◽  
Basudeb Sahu ◽  
I. Mehrotra

Predictions of the results of alpha-decay energy (Q-value) and decay half-life (t1/2) are made for experimentally unknown alpha decaying systems of superheavy nuclei. Following a theoretical method proposed recently by B. Sahu, the calculations are performed using the analytical expression of the potential that simulates the nuclear+Coulomb potential of the α + daughter nucleus system. The Q-value considered as resonance energy is calculated using the behavior of the wave function, and the t1/2 is expressed analytically using the exact solutions of the potential. A global formula for the potential parameter as a function of neutron number in a given isotopic chain of nuclei is developed for the calculation of Q and t1/2. Calculations of the latter two quantities are made for the decay chain of newly discovered superheavy elements 294117, 293117, and for the isotopic chains of Z = 74 and 102. Predictions of the same parameters are made for Z = 113 and some other still unknown superheavy nuclei. It is observed that the global formula works well in evaluating correct results of Q and t1/2 for various alpha emitters.


Sign in / Sign up

Export Citation Format

Share Document