Alpha decay half-life of bismuth isotopes

Abstract

The observed alpha decay half-life values of favoured alpha transitions of ℓ = 5 in bismuth isotopes have been analysed in the framework of a model based on quantum mechanical tunnelling through a potential barrier where the centrifugal and overlapping effects are taken into account. In particular, the very recently measured alpha decay half-life value of (1.9 ± 0.2) × 1019 y for the unique naturally occurring 209Bi isotope has been reproduced by the present approach as (1.0 ± 0.3) × 1019 y. Also, the partial alpha decay half-lives for a number of unmeasured alpha transitions of ℓ = 5 in bismuth isotopes are predicted by the model, thus making it possible to demonstrate the influence of the 126 neutron shell closure on the alpha decay half-life. The present approach is shown to be successfully applicable to other isotopic sequences of alpha-emitter nuclides.

Alpha decay of Europium isotopes

“…However, for the particular case of 151 Eu isotope a difference by a factor ∼5 is still present, which seems to indicate that very probably the alpha transition for this isotope does not proceed with = 0. previously in our alpha decay systematics, namely, that for bismuth isotopes [6] (g = 0.385 for = 5 transitions) and the one for all alpha decay cases of = 0 transitions [8] (g = 0.122). Next, a dependence of g upon is assumed of the form…”

“…a positive Q α -value [1]. However, for most of them the extremely high decay rates by the radioactive process of electron capture and, to a lesser extent, the β − -decay process, make alpha to alpha decay we developed [6][7][8][9] motivated by the discovery of a rare alpha activity in natural bismuth [10].…”

“…Parameter g is related to the penetrability factor through the overlapping region of nascent fragments or, in other words, to the "arrival" of the alpha particle at the nuclear surface, i.e. the alpha particle preformation probability (see [6] for details).…”

Simultaneous mutiparticle emission from compound nuclei in evaporation process

“…In equation (2.10), C = 1 − E * /B(Z i , A i ) represents the thermal correction to the chargedparticle Coulomb barrier [13] of the decaying nucleus with B(Z i , A i ) being its binding energy.…”

Systematic study ofαdecay half-lives for even-even nuclei within a two-potential approach

“…The traditional methods [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]such as the WKB approximation, and empirical formulas [23][24][25][26] are constantly evolving. Among these methods the microscopic * Corresponding author:lixiaohuaphysics@126.com double-folding model adopting density dependent M3Y force and the liquid drop model adopting the proximity potential have been researched frequently.…”