The dynamical cluster-decay model of preformed clusters for a hot and rotating¹¹⁶Ba* nucleus produced in the low-energy⁵⁸Ni +⁵⁸Ni reaction

Abstract

The dynamical cluster-decay model (DCM) is extended to a positive Q-value (Qout), heavy compound system 116Ba*, with complete angular momentum and charge dispersion effects included in it. The contributions due to both the light particles (LPs) and intermediate mass fragments (IMFs) are considered to give the total cross section. Interestingly, instead of the complete IMF spectrum observed for lighter systems such as 48Cr* and 56Ni*, here two small ‘windows of IMFs’ are predicted, one for light masses (2 ⩽ Z ⩽ 9) and another for the heavy mass end of symmetric and nearly symmetric fragments (14 ⩽ Z ⩽ 28), in agreement with the available data for the light mass ‘IMF window’ and its indications of possible extension to the heavier mass fragments. Within a non-statistical model description, the definition of phase space is found to be contained in the DCM definition of the ‘IMF window’ for the compound nucleus process. As in experiments, the calculated excitation functions are shown to put a limit on the minimum incident centre-of-mass energy required for the production of IMFs, and it will be of further interest to observe in experiments the predicted structures in the excitation functions of both the individual fragments, like for 12C decay, and the summed-up cross sections. Also, further measurements of the total kinetic energies of the fragments are called for.

Decay analysis of compound nuclei with massesA≈30–200formed in reactions involving loosely bound projectiles

“…The DCM, for the decay of compound systems, is non-statistical description of dynamical mass motion of preformed clusters through the interaction barrier which treats all types of emissions i.e. evaporation residues (or equivalently light particles LPs (A ≤ 4)), intermediate mass fragments IMFs (5 ≤ A 2 ≤ 20) and fusion-fission ff fragments, on the same footing [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. But the statistical models treat all these emissions on different footing, where these emissions are treated differently on the basis of mass of compound nucleus [28][29][30].…”

Theoretical study of odd-mass Fr isotopes using the collective clusterization approach of the dynamical cluster-decay model

“…[11][12][13][14][15][16][17][18][19][20][21][22]. In DCM, the decay cross section is defined in terms of the partial waves as…”

“…It is generally believed that decay of CN is independent of its mode of formation, except for the requirement of various conservation laws, and it can decay in a number of ways depending on the incident energy of the projectile and the deformations and shape orientations of both projectile and target nuclei. In general, the decay of CN goes through processes like the evaporation residue (ER), intermediate mass fragments (IMF), and fusion-fission (ff), described by various theoretical models, like the statistical evaporation [1][2][3][4][5] and fission model [6,7], the thermodynamical Dubna model of heated CN [8][9][10], and the dynamical cluster-decay model of Gupta and collaborators [11][12][13][14][15][16][17][18][19][20][21][22] used here. The ER consists of the light particles (LPs), neutrons, protons, α particles, and γ rays (A 4), whereas IMFs are nuclei with masses 5 A 20 and 2 Z 10 and ff comprises the near-symmetric and symmetric fission fragments, nSF and SF.…”

Pb208-daughter cluster radioactivity and the deformations and orientations of nuclei

“…The ground-state cluster decays of different parent nuclei in the trans-lead region have been observed by many experimental groups around the world, specifically, the clusters 14 C, 18,20 O, 23 F, 22,24,26 Ne, 28,30 Mg, 32 Si, and 34 Si, respectively, from 221−224,226 Ra, 226,228 Th, 231 Pa, 230,232,234 U, 236,238 Pu, 238 Pu, and 242 Cm parents [3,4]. Also, 14 C decay from 221 Fr and 225 Ac, and, more recently 14 C from 223 Ac and 34 Si from 238 U are observed [5].…”