SYSTEMATIC CALCULATION OF α-DECAY HALF-LIVES WITHIN GENERALIZED DENSITY-DEPENDENT CLUSTER MODEL

2010 ◽  
Vol 19 (08n09) ◽  
pp. 1592-1602 ◽  
Author(s):  
DONGDONG NI ◽  
ZHONGZHOU REN
Keyword(s):  
Wave Function ◽  
Cluster Model ◽  
Nuclear Potential ◽  
Α Decay ◽  
Density Dependent ◽  
Systematic Calculation ◽  
State Wave ◽  
Scattering State ◽  
The Difference ◽  
Double Folding

An improved version of the generalized density-dependent cluster model is presented to describe an α particle tunneling through a microscopic potential barrier. The microscopic potential is numerically constructed in the double folding model for both the Coulomb potential and the nuclear potential. The decay width is computed using the integral of the quasibound state wave function, the scattering state wave function, and the difference of potentials. We perform a systematic calculation of α-decay half-lives for even-even, odd-A, and odd-odd nuclei ranging from N = 84 to N = 126. The calculated α-decay half-lives are found to be in good agreement with the experimental values.

DENSITY-DEPENDENT CLUSTER MODEL OF α DECAY

2005 ◽  
Vol 19 (15n17) ◽  
pp. 2365-2368 ◽  
Author(s):  
CHANG XU ◽  
ZHONGZHOU REN
Keyword(s):  
Nuclear Physics ◽  
Cluster Model ◽  
Daughter Nucleus ◽  
Nucleon Nucleon ◽  
Nucleon Interaction ◽  
Α Decay ◽  
Density Dependent ◽  
Density Distributions ◽  
Nucleon Nucleon Interaction ◽  
Double Folding

A new cluster model of α decay is proposed where the effective potential between α-cluster and daughter nucleus is obtained from the double folding integral of the renormalized M3Y nucleon-nucleon interaction and of the density distributions of α particle and daughter nucleus. Without introducing any extra adjustment on the potential, the new model (named as the density-dependent cluster model) can successfully reproduce the experimental half-lives of α decay within a factor of 3. The model also works well for new superheavy elements which are the current interests of nuclear physics and chemistry.

Alpha decay and spontaneous fission in superheavy isotopes, Z = 124, using a density-dependent cluster model

2020 ◽  
pp. 2050096
Author(s):  
S. A. Seyyedi
Keyword(s):  
Empirical Formula ◽  
Half Life ◽  
Cluster Model ◽  
Spontaneous Fission ◽  
Alpha Decay ◽  
Nucleon Nucleon ◽  
Empirical Formulas ◽  
Density Dependent ◽  
Double Folding ◽  
Semi Empirical

Alpha decay (AD) and spontaneous fission (SF) half-lives of superheavy nuclei [Formula: see text] have been studied within the density-dependent cluster model. The alpha-nucleus potentials were calculated using the double-folding model with the realistic M3Y nucleon–nucleon interaction. To calculate nuclear half-lives, several semi-empirical formulas were used in addition to the Wentzel–Kramers–Brillouin (WKB) approximation. The calculated AD half-lives agree well with the values computed by the analytical formulas of Royer, the semi-empirical formula of Poenaru et al. and the Viola–Seaborg systematic. To identify the mode of decay of these nuclei, the SF half-lives were calculated using the semi-empirical formula given by Xu et al. The results show that among the isotopes studied, isotopes [Formula: see text] can be survived from the SF and have a half-life greater than [Formula: see text][Formula: see text](s). The study predicts [Formula: see text] chains from isotopes [Formula: see text], [Formula: see text] chains from isotopes [Formula: see text], [Formula: see text] chains from isotopes [Formula: see text] and an AD from [Formula: see text]. These isotopes have a half-life long enough to be synthesized in the laboratory. Also, in the decay chains of these isotopes, it is observed that the nuclei [Formula: see text] have higher half-lives than their neighbors. The neutron numbers corresponding to these isotopes are [Formula: see text] indicating the magical or semi-magical behavior of these numbers, which is in good agreement with the research results.

THEORETICAL CALCULATIONS ON α-DECAY HALF-LIVES BY THE DENSITY-DEPENDENT CLUSTER MODEL

2008 ◽  
Vol 23 (27n30) ◽  
pp. 2597-2603
Author(s):  
ZHONGZHOU REN ◽  
CHANG XU
Keyword(s):  
Cluster Model ◽  
Theoretical Calculations ◽  
Light Nuclei ◽  
Α Decay ◽  
Density Dependent ◽  
Theoretical Results ◽  
Good Agreement

The theoretical calculations of α-decay half-lives for three kinds of α-emitters (even-even, even-odd, odd-odd nuclei) are systematically reviewed within the framework of the density-dependent cluster model (DDCM). The half-lives of three typical α-emitters (8 Be , 212 Po , and 270 Ds ) are discussed in detail. The good agreement between experimental and theoretical results shows that DDCM is applicable in the whole mass table from very light nuclei to heavy and superheavy ones.

S-MATRIX AND WAVE FUNCTION METHODS FOR THE CALCULATION OF SMALL DECAY WIDTHS

2010 ◽  
Vol 25 (07) ◽  
pp. 535-547 ◽  
Author(s):  
BASUDEB SAHU ◽  
Y. K. GAMBHIR ◽  
C. S. SHASTRY
Keyword(s):  
Wave Function ◽  
Bound States ◽  
Spherical Wave ◽  
Bound State ◽  
Experimental Results ◽  
Q Value ◽  
Α Decay ◽  
State Wave ◽  
Bound State Wave Function ◽  
S Matrix

Most of the decaying systems namely α-decay and proton radio activity have extremely narrow widths and hence are termed as quasi-bound states. There are three methods available for the computation of very narrow widths. First, the analytic S-matrix method which treats resonance as a pole in complex energy plane with its real part representing resonance energy and the imaginary part the half width. Another two methods namely (i) direct (D) method and (ii) distorted wave (DW) method are based on the property of the quasi-bound state wave function which is quite similar to a bound state wave function in the interior region and is matched with an outgoing spherical wave representing decaying behavior. We make a comparative study of these methods by applying them to the α-decay systems whose experimental results of Q-value and decay half-lives are known recently. It is observed that all the three methods give practically the same results for widths calculated at the same Q-value and explain the experimental results of Q-values and half-lives in several α-decaying nuclei quite well with a proper Coulomb nuclear interaction potential for the α+daughter nucleus system.

THEORETICAL STUDY ON HALF-LIVES OF EXOTIC RADIOACTIVITIES

2006 ◽  
Vol 15 (07) ◽  
pp. 1569-1575
Author(s):  
CHANG XU ◽  
ZHONGZHOU REN
Keyword(s):  
Cluster Model ◽  
Theoretical Study ◽  
Proton Emission ◽  
Decay Energy ◽  
Α Decay ◽  
Density Dependent ◽  
Quantum Tunnelling ◽  
Analytical Formulas ◽  
Unified Description ◽  
Theoretical Results

We systematically investigate the half-lives of exotic radioactivities in the framework of the density-dependent cluster model. Simple analytical formulas between lifetime and decay energy are also derived for the exotic radioactivities based on the Gamow quantum tunnelling theory. The theoretical results from the density-dependent cluster model and from the analytical formulas agree well with the experimental data. A unified description is achieved for proton emission, α-decay and cluster radioactivity by both phenomenological and microscopic methods.

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