Studies on light, medium, and heavy cluster radioactivity in even-even ^300–314122 isotopes

Abstract Using the analytical super asymmetric fission model (ASAFM), we have studied the light ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>Z</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>c</mml:mi> </mml:mrow> </mml:msub> <mml:mo>≤</mml:mo> <mml:mn>14</mml:mn> </mml:math> ), medium ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>14</mml:mn> <mml:mo>&lt;</mml:mo> <mml:msub> <mml:mrow> <mml:mi>Z</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>c</mml:mi> </mml:mrow> </mml:msub> <mml:mo>&lt;</mml:mo> <mml:mn>28</mml:mn> </mml:math> ), and heavy ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>Z</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>c</mml:mi> </mml:mrow> </mml:msub> <mml:mo>≥</mml:mo> <mml:mn>28</mml:mn> </mml:math> ) cluster emission from even–even isotopes of superheavy nuclei Z = 122 in the mass region A = 300–314. The predicted half-lives for alpha and light clusters are compared with the predictions using different formalisms, such as the universal decay law (UDL), universal (UNIV) curve, and improved universal (Imp UNIV) curve. It is observed that UDL predictions have the least deviation from ASAFM values. The dip observed in the plot of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>log</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> </mml:msub> <mml:msub> <mml:mrow> <mml:mi>T</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>1</mml:mn> <mml:mo>/</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> </mml:math> versus mass number, for alpha decay, at mass number A = 308 highlights the stability of daughter nuclei 304 120, which is due to the neutron shell closure at N = 184 and predicted proton shell closure at Z = 120. We have identified isotopes of Sr, Zr, Mo, Cd, In, Sn, etc are the heavy clusters with half-lives comparable to alpha half-lives. The heavy clusters 82 Ge, 83 As, 84 Se, 85 Br, 86 Kr, etc are also probable for emission from 300–314 122. The role of deformed and spherical proton shell closure Z = 38, 40, 50, 82 and spherical neutron shell closure N = 50, 82, 126 of emitted cluster and residual nuclei are evident in heavy cluster radioactivity. The modes of decay of isotopes 300–314 122 are analysed by comparing α half-lives and corresponding spontaneous fission (SF) half-lives evaluated by using the improved formula of Yuan et al It is found that the isotopes 300 122, 302 122, 304 122, 306 122, and 308 122 will survive spontaneous fission and decay via 8 α chains, 5 α chains, 2 α chains, 3 α chains, and 1 α chain, respectively, which could be of great interest to the experimentalists.