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In this paper, we systematically investigate the cluster decay half-lives of heavy nuclei using the Wentzel–Kramers–Brillouin method and Bohr–Sommerfeld quantization condition for the Morse molecular potential. We determine the optimal nuclear potential parameters that best fit the experimental data of known cluster decay half-lives. Subsequently, we theoretically calculate the cluster decay half-lives for the heavy nuclei lacking experimental decay half-lives. Our findings reveal that the Morse model is highly effective in explaining the decay half-lives of the heavy nuclei, particularly when utilizing two degrees of freedom. This approach produces results that match the accuracy of empirical models found in the existing literature. Theoretical determinations of cluster decay half-lives with optimally derived model parameters are expected to guide future experimental studies. [ABSTRACT FROM AUTHOR]

The Coulomb and Proximity potential Model (CPPM) is improved by introducing an accurate empirical expression for the nuclear surface diffuseness parameter in the expression for the proximity potential. Within the improved CPPM, the decay half-lives of experimentally detected cluster emissions from heavy elements are calculated. The results of the calculations using the Universal Decay Law (UDL) [Qi et al., Phys. Rev. Lett. 103 (2009) 072501], the improved empirical formula of Sahu et al. (ImSahuB) [Wang et al., Chin. Phys. C 45 (2021) 044111], and the empirical formula of Horoi [J. Phys. G. Nucl. Part. Phys. 30 (2004) 945] are compared with the predictions of the improved CPPM. The lowest standard deviation is obtained for the predictions using the improved CPPM. The model's predictive power increases significantly when the proximity potential is modified by including the diffuseness parameter. Furthermore, improved CPPM is employed to calculate the decay half-lives of undiscovered cluster emissions from heavy elements, a valuable information for upcoming experimental investigations. The calculated values are compared with the predictions of the UDL, Horoi formula and the improved empirical formula of Sahu et al. (ImSahuB). There is a high degree of agreement between the improved CPPM, UDL, and Horoi formula predictions. The ImSahuB formula predict decay half-life one or two order magnitudes lower than the predictions of the other models. [ABSTRACT FROM AUTHOR]

The cluster radioactivity of 2 2 2 , 2 2 4 , 2 2 6 Ra, 2 2 3 , 2 2 5 Ac, 2 3 2 , 2 3 4 , 2 3 5 , 2 3 6 U, 2 3 6 , 2 3 8 Pu, 2 3 4 , 2 3 6 U, 2 3 2 , 2 3 3 , 2 3 4 , 2 3 5 , 2 3 6 U and 2 3 0 , 2 3 2 Th isotopes which emitted 1 4 C, 2 4 Ne, 2 8 Mg, 2 6 Ne, 2 8 Mg, 2 4 Ne, respectively, has been analyzed with the help of fractional calculus for investigating the connection between order of the fractional derivative and nuclear structure. When the neutron number of daughter nuclei is equal to magic number, order of the fractional derivative shows a maximum. It is shown that there is a relationship between the order of fractional derivative and shell effect. This order has a similar role to the preformation factor in cluster radioactivity. [ABSTRACT FROM AUTHOR]

The Cubic plus Yukawa plus Exponential (CYE) model has been used to study the different decay properties of Superheavy nuclei 298,310114, 306,318122, 308,310124, 310,322126 and compared them with the available theoretical and experimental values. Here, the half-lives of several clusters have been computed that have not yet been detected experimentally. Hopefully, this will assist future research in this area. As a result of comparing the three different decay modes (α-decay, cluster radioactivity and spontaneous fission), it was possible to predict the predominant decay modes of Superheavy nuclei. [ABSTRACT FROM AUTHOR]

Based on the Unified Fission Model with a Woods–Saxon potential (UFMWS), we have investigated alpha decay and cluster radioactivity of actinide nuclei. To ensure accuracy, we determined the most precise Q -values by comparing the results of four nuclear mass models: the liquid drop model (LDM), the DZ28 model, the WS4 model, and the finite range droplet model (FRDM), which were recently improved using a machine learning algorithm. Among these models, it is found that the improved WS4 (IWS4) provides the most accurate Q -values, enabling the UFMWS model to effectively reproduce experimental alpha and cluster decay half-lives. Consequently, the UFMWS model using IWS4 Q -values was employed to explore various combinations of parent nuclei and alpha particle as well as even–even emitted clusters ranging from Be to Si. The obtained results are consistent with previous study that identified minima in half-lives near corresponding to the doubly magic 2 0 8 Pb daughter nucleus or its neighboring nuclei. It is found that neutron-deficient parent nuclei generally displayed the shortest half-lives, most of which are within the experimental range. Considering the experimental limitations, cluster decays favorable for measurement in the actinide region were identified. Interestingly, these decays did not involve the most neutron-deficient nuclei. [ABSTRACT FROM AUTHOR]

Synthesis of superheavy elements (SHE) being the foremost aim related to the study of superheavy elements, reactions for producing various isotopes of SHEs with Z = 118 are developed. For developing the reactions, we used concepts related to cluster decay. The driving potential minimum associated with each mass asymmetric split of an isotope is found, and its variation with cluster mass is studied. It has been found that, in addition to the general pattern of consecutive minimum, termed cold valley, and maximum, in the driving potential minima of an isotope, there are local regions having comparatively lower values of driving potential minima, which have their own least values of driving potential minima. The reactions associated with such least values are presented as probable reactions, the order of probability being such that the smaller the least value, the larger the probability, for the production of isotopes. One of the reactions elicited in this manner for isotope 294118 is the reaction of the recognised production of Z = 118. [ABSTRACT FROM AUTHOR]

Elements from iron to uranium are expected to have been produced in the r-process nucleosynthesis via rapid neutron capture at elevated temperatures of the order of Giga Kelvins (GK). The network of coupled differential equations used to determine the abundance of elements thus involves nuclear reaction rates at elevated temperatures. The path of the r-process nucleosynthesis is along highly unstable nuclei and hence nuclear decay rates play an important role too. However, standard codes available for such calculations make use of terrestrial half-lives for alpha decay. Within a statistical approach and using data on excited nuclei, we find that for temperatures between 1-2 GK, the alpha decay half-lives can decrease by a few orders of magnitude as compared to the terrestrial ones. Based on these results, an estimate for the variations of the abundance of elements due to temperature-dependent half-lives is provided for a high entropy wind scenario. A model for the radioactive decay of thermally excited heavy nuclei by emitting an alpha or a light cluster such as 14C, 20O, or 28Mg is also presented and applied to evaluate the less known light cluster decay rates. [ABSTRACT FROM AUTHOR]

The decay characteristics of various clusters and neutron halo nuclei from heavy elements Z = 9 2 − 1 0 2 are studied within the framework of the Coulomb and Proximity Potential Model for Deformed Nuclei (CPPMDN) and using a new empirical formula proposed by us. The predictive power of our formula is verified by comparing the predictions with the available experimental data and with the predictions of other models such as CPPM, Universal Decay Law of Qi et al. (UDL), Unified Description formula (UD) of Ni et al. Using the present formula and CPPMDN, decay half-lives of various light clusters from heavy elements are calculated, and the results are compared with the predictions of UDL, UD, and predictions made by Santhosh et al. based on the Modified Generalized Liquid Drop Model (MGLDM). The decay half-lives of halo nuclei from heavy elements are also calculated using the new formula and CPPMDN and compared with the predictions of UDL, UD, and the predictions made by Santhosh et al. based on the Coulomb and Proximity Potential Model (CPPM). [ABSTRACT FROM AUTHOR]

We have made an attempt to parameterize decay energies (Q) during the cluster emissions such as 4He, 6Li, 9Be,20,22Ne, 23Na, 24−26 Mg, 27Al, 28−30Si, 32−34S, 35Cl, 36,38,40Ar, 39,41 K and 40,42–44,46Ca from the superheavy nuclei 103 < Z < 126. We have formulated an empirical formula for decay energies of superheavy nuclei during the emission of different clusters of nuclei. To check the predictive power of constructed formula, we have compared the decay energies produced by the present formula with that of the experiments. The constructed empirical formula can reproduce the Q-values during the cluster emissions using simple inputs of mass number of daughter nuclei, atomic number of cluster emission and neutron number of parent nuclei. [ABSTRACT FROM AUTHOR]

The radioactive decay probabilities of various proton halo (p-halo) nuclei from parent isotopes in the superheavy (SH) region, Z = 115–120, were analysed by taking the Coulomb and proximity potential as the interacting barrier. The nuclear decay half-lives ( t 1 / 2 ) , barrier penetrability and various other attributes for the decay of p-halo nuclei such as 8 B, 9 C, 11 , 12 N, 17 F, 17 , 18 Ne, 23 Al and 26 , 27 , 28 P from the isotopes 261 -- 278 115 , 264 -- 279 116 , 267 -- 284 117 , 271 -- 283 118 , 274 -- 288 119 and 277 -- 285 120 are determined. From the determined decay lifetime values, it is understood that most of the p-halo decays are probable. The error bars in the halo radius are incorporated for the nuclear decay half-life for these p-halo nuclei. Moreover, the effects of shell closure in the daughter and the parent nuclei are also clear from the plots of calculated decay half-lives vs. neutron number of the daughter nuclei. Peak and dip in the plots show the closed shell effects of the parent and daughter nuclei respectively. We found the closed shell effect of the parent at N p ∼ 152 and closed shell effect of the daughter nuclei at N d ∼ 132 , 142 . Further, we have analysed the Geiger–Nuttall (GN) plots of logarithmic half-life time vs. Q - 1 / 2 and the universal curve of logarithmic half-life time against negative logarithm of the barrier penetrability for the chosen p-halo decay from the SH parents, Z = 115 -- 120 and are found to be linear. Also, we can find that the addition of proximity potential does not make any notable variation in the behaviour of the Geiger–Nuttall plots. Hence GN law is also applicable to p-halo decay. [ABSTRACT FROM AUTHOR]

We have studied the clusters (12C, 16O, and 20Ne) decay half-lives in the transition metal region (158-170W, 160-174Os, and 166-178Pt, respectively). These half-lives have been calculated using the effective liquid drop model (ELDM) of cluster decay in conjunction with the relativistic mean-field (RMF) model with the NL3* parameter set. Thus calculated cluster decay half-lives are also compared with the half-lives computed using the latest empirical relations, namely Universal decay law (UDL) and the Scaling Law was given by Horoi et al. From the calculated results, it has been observed that in the transition metal region, half-lives are minimum at Nd = 82 (Nd is the neutron number of the daughter nuclei), which is a magic number and shell effect at Nd = 82. Further, the Geiger-Nuttal plots of half-lives showing Q-value dependence for different alpha-like clusters from various CR emitters that have been plotted are found to vary linearly. [ABSTRACT FROM AUTHOR]

Using modified generalized liquid drop model, we have studied all possible cluster decay modes of superheavy nuclei 287Mc using different nuclear potentials. The daughter or residual nuclei is having magic nuclei or semi-magic nuclei. The total potential is evaluated by considering quantum tunneling process. The lower limit of cluster emission is from Zmin e = 2 and upper limit of cluster emission considered is Zmax e = Z - 82 . The studied different nuclear potentials such as Danisov, AW-91, BW-91 and Bass-73 shows shorter half-lives and larger relative yield for the cluster emission 74Ge. Hence, the possible cluster decay is with the combination 74Ge+213Bi. [ABSTRACT FROM AUTHOR]

Cluster decay of the superheavy nuclei 270 -- 318 118 has been studied taking Coulomb and proximity potentials as interacting barriers. This study is based on the concept of cold valley. Cluster decay half-lives and other characteristics are computed for various clusters. The predicted α decay half-life values are compared with other theoretical models and also with the sole experimental value. Plots connecting half-lives with the neutron number of the daughter nuclei as well as with the neutron number of the parent nuclei, strongly indicated neutron shell closure at N = 184 . Also, we noted that proton shell closure occurs at Z = 114 . From our studies, we noted that the nuclide 184 298 114 , which is doubly closed, is very stable and we could reach the inference that 184 298 114 is the most probable nuclide to be the centre of island of stability. [ABSTRACT FROM AUTHOR]

The half-lives of an alpha decay and cluster radioactivity in superheavy odd nuclei such as 272–283Rg, 283–287Nh, 287–291Mc, 289–297Ts, 292–299Uue, 299–305121, 297–317123, and 307–319125 were studied using the modified generalized liquid drop model (MGLDM) and the temperature-dependent (TD) and temperature-independent (TIND) models. The alpha decay half-life results obtained from the three different models were compared with each other and with Dong et al.'s [Nucl. Phys. A 832, 198 (2010)] formula and the effective liquid droplet model (ELDM). Based on this, we have predicted the decay modes for studied superheavy nuclei. Finally, we have also compared the present work with experimental values. These observations will be helpful for further experimental investigations in this region. [ABSTRACT FROM AUTHOR]

We have studied systematically the alpha decay and cluster radioactivity half-life of heavy 2 4 5 − 2 6 0 Mendelevium (Z = 1 0 1) isotopes. The alpha decays from Md isotopes have been studied within the framework of Coulomb and proximity potential model using 14 different versions of nuclear potentials. Also, we have studied the half-lives of alpha decay of Md nuclei within the nuclear potentials generalized liquid drop model (GLDM) and also within GLDM with modified different nuclear potentials, namely proximity potential 2010, 1977, 1988, 2000 and 2002. Moreover, the half-lives of the α -decay and cluster radioactivity calculated using the Universal formula for cluster decay (UNIV) of Poenaru et al., the Universal decay law (UDL) of Qi et al. and the Unified formula of half-lives for both the α -decay and cluster radioactivity (UFADCR) of Ni et al. and found to be in good agreement. Our results have been compared with experimental data and demonstrate the acceptability of the approach. Among the different proximity potentials, GLDM with proximity 1977 version (GLDM + P77) (σ = 0. 8 5 0 9) provides the best description for alpha decay studies with low deviation. [ABSTRACT FROM AUTHOR]

Various decay modes in superheavy nuclei have been of significant interest among which cluster radioactivity has recently gained sizable attention. The α -decay being a predominant decay mode in the superheavy region, the accurate determination of cluster decay half-lives is also crucial in this region as it has tremendous potential to be explored as one of the major decay channels. The usability of the Royer analytical formula [Nuclear Physics A 683 (2001) 182], which is based on the asymmetric fission model, has been investigated for the cluster and α -decay in superheavy region, by comparing it with several other (semi)empirical/analytical formulas. After fitting the formula on around 100 cluster-decay data and around 423 α -decay data, the refitted Royer formula (RRF) is found to be very robust which is able to estimate the cluster decay and α -decay half-lives with good accuracy. In fact, a comparison of the half-lives of both the decay modes using the same formula points towards a substantial chance of heavy cluster (Kr and Sr) decay from various isotopes of Z=118 and 120. Hence, the formula proposed in this study works fairly well for the estimation of cluster decay half-lives in superheavy regions where most empirical formulas fail to match with the half-lives from the various established theories. [ABSTRACT FROM AUTHOR]

The competition between different decay modes such as binary fission, ternary fission, cluster and alpha decay modes finds an important role in the synthesis of superheavy nuclei. The nuclei 281Ds is the most stable among the isotopes of Ds. We have studied the different decay modes in superheavy nuclei 281Ds. It is observed that alpha decay half-lives are smaller compared to other modes. The alpha decay mode of 281Ds is observed with greater probability compared to binary fission. [ABSTRACT FROM AUTHOR]

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 Z = 1 3 0 – 1 4 4 superheavy nuclei are studied within the range 2 9 0 ≤ A ≤ 3 8 0. The calculated decay half-lives are in good agreement with other theoretical approaches. The signature of neutron shell closure at N = 1 7 2 , 1 8 4 , 1 9 8 , 2 2 8 , 2 3 8 and proton shell closure at Z = 1 3 8 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 Z with increasing A 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 1 0 − 6 s ≤ T 1 / 2 ≤ 1 0 3 0 s are presented. [ABSTRACT FROM AUTHOR]

Abstract The alpha decay half-lives of some deformed superheavy nuclei and cluster decay half-lives of some deformed heavy nuclei were calculated in framework of WKB semiclassical method and by including Bohr–Sommerfeld quantization condition. Deformed double-folding nuclear and Coulomb potentials, and centrifugal potential have been considered for effective potential. Two forms of deformed surface diffuseness were used for calculations of alpha decay half-lives. In most of cases the calculated alpha decay half-lives with proposed deformed surface diffuseness were in better agreement with experiment in comparison with constant one. By using available experimental data, the cluster preformation probabilities were determined. Predicted cluster decay half-lives with inclusion of two different cluster preformation probability formulas were compared with those values of two empirical formulas. It was revealed the significant role of preformation probability in the cluster decay half-life calculations. [ABSTRACT FROM AUTHOR]

Using the Hartree–Fock–Bogoliubov mean-field theory, the ground-state structural and decay properties of Nd isotopes are investigated from the proton-rich side up to the neutron drip-line. Quantities such as binding energies per nucleon, one and two-neutron separation energies, rms charge radii, and quadrupole deformation parameters have been calculated. Compared with the relativistic mean-field results, the present calculations are in better agreement with the available experimental data. The results show clearly the signature of a shape transition at N = 9 0 and an abrupt increase in the deformation near the neutron drip-line. Further, the possible decay modes like alpha, cluster and β -decay are analyzed in a unified fission model and phenomenological formulas. Overall, a good agreement is achieved between the calculated and experimental Q -values and half-lives wherever available. The most likely decay modes are thus identified throughout the isotopic chain. [ABSTRACT FROM AUTHOR]

The DAMA project has obtained many competitive or new results in the search for various rare nuclear processes. Most of them have been obtained with the help of many different high purity crystal scintillators which have been measured in the low-background DAMA set-ups located in the Gran Sasso underground laboratory of INFN In this paper, the main results will be summarized. [ABSTRACT FROM AUTHOR]

In the nuclear tunneling processes involving deformed nuclei, most of the tunneling-related quantities depend on the relative orientations of the participating nuclei. In the presence of different multipole deformations, we study the variation of a few relevant quantities for the α-decay and the sub-barrier fusion processes, in an orientation degree of freedom. The knocking frequency and the penetration probability are evaluated within the Wentzel–Kramers–Brillouin approximation. The interaction potential is calculated with Skyrme-type nucleon–nucleon interaction. We found that the width of the potential pocket, the Coulomb barrier radius, the penetration probability, the α-decay width, and the fusion cross-section follow consistently the orientation-angle variation of the radius of the deformed nucleus. The orientation distribution patterns of the pocket width, the barrier radius, the logarithms of the penetrability, the decay width, and the fusion cross-section are found to be highly analogous to pattern of the deformed-nucleus radius. The curve patterns of the orientation angle distributions of the internal pocket depth, the Coulomb barrier height and width, as well as the knocking frequency simulate inversely the variation of the deformed nucleus radius. The predicted orientation behaviors will be of a special interest in predicting the optimum orientations for the tunneling processes. [ABSTRACT FROM AUTHOR]

The half-lives of the cluster decay (CD) from the isotopes having the known experimental values, the half-lives of the -decay (AD) of same nuclei and also the branching ratios are obtained, within the framework of two-potential approach with cosh potential including with and without the isospin effects. Using two-potential approach and taking into account the isospin effects in the calculations decrease the rms values and they improve the results. The obtained branching ratios are in good agreement with the experimental ones for some isotopes. It is obtained that the isospin-dependent potentials have an influence on the half-lives of the cluster decays of nuclei. Present calculations would be important for predicting the experimental half-lives and branching ratios for the cluster decays of different types of isotopes. [ABSTRACT FROM AUTHOR]

The most probable cluster decays that can be observed for 217 – 238 U isotopes are investigated. We identified the more-probable decays that commonly manifest themselves via cold valleys in the driving potentials with respect to the mass number and the atomic number, individually. The calculations are performed using the Skyrme-SLy4 nucleon–nucleon interaction, within the frame work of the performed cluster model. Among the indicated favored decays that involve emitted light clusters heavier than α -particle, twenty six decay modes display calculated half-life less than 10 22 years, with branching ratio larger than 10 −14 %. The estimated branching ratio for the α -decay of 237 U, that did not observed yet, is B = 2.1 × 10 − 10 % ( T α = 8.7 × 10 9 years ). The indicated most probable decays that did not observed yet include the 22 Ne decay of 232 U, 25 Ne and 32 Si decays of 233 U, 24 Ne and 29 Mg decays of 235 U, and the 34 Si and 30 Mg decay modes of 238 U, with 10 − 14 < B (%) < 10 − 7 . [ABSTRACT FROM AUTHOR]

The half-lives of cluster decays from various nuclei having experimentally measured values have been calculated by using the Wentzel-Kramers-Brillouin method together with the Bohr-Sommerfeld quantization condition for three different types of phenomenological nuclear interactions: Woods-Saxon (WS), squared Woods-Saxon (WS-2), and mixed Woods-Saxon (mWS) potentials. By comparing the results with experimental values, rms values have been calculated. The half-lives of 14C, 15N, 16O, 17O, 18O, 20O, 22O, 23F, 22Ne, 24Ne, 25Ne, 26Ne, 28Mg, 30Mg, and 34Si decays from various isotopes whose experimental half-lives are unknown have also been calculated by using the WS, WS-2, and mWS potentials. The obtained results have been compared with results of the liquid drop model, the Christensen-Winther potential form, and the Coulomb and proximity potential model. Even if the logarithmic values of the half-lives have similar behaviors, there are differences in size between the values. The present results provide useful information and extra theoretical data for future measurements of the unknown half-lives of possible cluster emissions from various nuclei. [ABSTRACT FROM AUTHOR]

A transfer-reaction experiment of Be(Be, Be)Be was performed at a beam energy of 45 MeV. Excited states in Be up to 18.80 MeV are produced using missing mass and invariant mass methods. Most of the observed high-lying resonant states, reconstructed from the α + He and t + Li decay channels, agree with the previously reported results. In addition, two new resonances at 15.6 and 18.8 MeV are identified from the present measurement. The 18.55 MeV state is found to decay into both the t + Li. and t + Li* (0.478 MeV) channels, with a relative branching ratio of 0.93 ± 0.33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei. [ABSTRACT FROM AUTHOR]

Three disintegration modes of the parent nucleus 222 Ra , namely the fission, the cluster emission and the alpha decay, are treated in a unified manner. The half-lives are calculated by taking into account the penetration probabilities through the potential barrier along disintegration trajectories in the deformation space appropriate to each kind of decay. These trajectories start from the same parent ground state configuration. The disintegration paths are obtained from the least action principle. The deformation energy is calculated within the macroscopic–microscopic procedure based on the Woods–Saxon two center shell model. The effective mass is determined microscopically with the cranking method and the Gaussian Overlap Approximation. The nuclear shape parametrization is characterized by the most important five degrees of freedom encountered in fission, corresponding to the elongation, the mass asymmetry, the necking and the two fragment deformations. Partial half-life results for alpha-decay and cluster emission processes treated as superasymmetric fission agree with the experimental data. The spontaneous fission half-life is predicted. Molecular states are evidenced for the superasymmetric fission process as a result of the large shell effects in the nascent fragments. [ABSTRACT FROM AUTHOR]

We investigate the emission of alpha particles and various clusters from uranium isotopes using the Effective Liquid Drop Model. The study has been carried out for the isotopes ranging between the p-drip-line and beta stability line. The half-lives calculated are in good agreement with the Universal Decay law, the scaling law of Horoi et al. and also with the available experimental values. We have listed the half-lives of all probable decay modes of uranium isotopes. The uncertainties in Q -value and half-lives are also presented. It is also observed that the probability of cluster emission decreases with the increase of neutron number of parent nuclei. The linear nature Geiger-Nuttal plot has been reproduced for the prominent decay modes. The study also affirms the inevitable role of neutron magicity in cluster radioactivity. We have also analyzed the branching ratios to identify the most prominent decay modes of uranium isotopes. [ABSTRACT FROM AUTHOR]

Nuclear cluster radioactivity is investigated using microscopic potentials in the framework of the Wentzel–Kramers–Brillouin approximation of quantum tunneling by considering the Bohr–Sommerfeld quantization condition. The microscopic cluster–daughter potential is numerically constructed in the well-established double-folding model. A realistic M3Y-Paris NN interaction with the finite-range exchange part as well as the ordinary zero-range exchange NN force is considered in the present work. The influence of nuclear deformations on the cluster decay half-lives is investigated. Based on the available experimental data, the cluster preformation factors are extracted from the calculated and the measured half lives of cluster radioactivity. Some useful predictions of cluster emission half-lives are made for emissions of known clusters from possible candidates, which may guide future experiments. [ABSTRACT FROM AUTHOR]

The decay properties of various even-even isotopes of barium in the range 112 ≤ A ≤ 122 is studied by modifying the Coulomb and proximity potential model for both the ground and excited state decays, using recent mass tables. Most of the values predicted for ground state decays are within the experimental limit for measurements ( T < 10 s). The minimum T value refers to doubly magic or nearly doubly magic Sn ( Z= 50) as the daughter nuclei. A comparison of log ( T) value reveals that the exotic cluster decay process slows down due to the presence of excess neutrons in the parent nuclei. The half-lives are also computed using the Universal formula for cluster decay (UNIV) of Poenaru et al and the Universal decay law (UDL) of Qi et al, and are compared with CPPM values and found to be in good agreement. A comparison of half-life for ground and excited systems reveals that probability of decay increases with a rise in temperature or otherwise, inclusion of excitation energy decreases the T values. [ABSTRACT FROM AUTHOR]