Phys.Rev. C 88, 054618 (2013)

R.du Rietz, E.Williams, D.J.Hinde, M.Dasgupta, M.Evers, C.J.Lin, D.H.Luong, C.Simenel, A.Wakhle

Mapping quasifission characteristics and timescales in heavy element formation reactions

NUCLEAR REACTIONS ¹⁸⁶W(¹⁶O, X)²⁰²Pb*, E(cm)=102.1 MeV; ¹⁹²Os(¹⁶O, X)²⁰⁸Po*, E(cm)=102.3 MeV; ¹⁷⁸Hf(²⁴Mg, X)²⁰²Po*, E(cm)=102.1 MeV; ¹⁶⁸Er(³⁴S, X)²⁰²Po*, E(cm)=128.4 MeV; ¹⁴⁴Sm(⁴⁸Ti, X)¹⁹²Po*, E(cm)=164.2 MeV; ¹⁹⁶Pt(¹⁶O, X)²¹²Rn*, E(cm)=102.0 MeV; ²⁰⁸Pb(¹²C, X)²²⁰Ra*, E(cm)=59.9 MeV; ²⁰⁰Hg(¹⁶O, X)²¹⁶Ra*, E(cm)=102.8 MeV; ¹⁷⁸Hf(³²S, X)²¹⁰Ra*, E(cm)=138.3 MeV; ¹⁶²Dy(⁴⁸Ti, X)²¹⁰Ra*, E(cm)=168.9 MeV; ²⁰⁸Pb(¹⁶O, X)²²⁴Th*, E(cm)=103.0 MeV; ¹⁸⁶W(³⁴S, X)²²⁰Th*, E(cm)=144.5 MeV; ¹⁷⁰Er(⁴⁸Ti, X)²¹⁸Th*, E(cm)=174.8 MeV; ¹⁵⁴Sm(⁶⁴Ni, X)²¹⁸Th*, E(cm)=200.6 MeV; ¹⁷⁴Yb(⁴⁸Ti, X)²²²U*, E(cm)=178.1 MeV; ¹⁹⁴Pt(³²S, X)²²⁶Pu*, E(cm)=144.4 MeV; ¹⁷⁸Hf(⁴⁸Ti, X)²²⁶Pu*, E(cm)=180.8 MeV; ²⁰⁸Pb(³⁰Si, X)²³⁸Cm*, E(cm)=134.7 MeV; ²⁰²Hg(³²S, X)²³⁴Cm*, E(cm)=149.6 MeV; ¹⁸⁶W(⁴⁸Ti, X)²³⁴Cm*, E(cm)=186.3 MeV; ¹⁷⁰Er(⁶⁴Ni, X)²³⁴Cm*, E(cm)=216.2 MeV; ²³⁸U(¹²C, X)²⁵⁰Cf*, E(cm)=66.3 MeV; ²³²Th(¹⁸O, X)²⁵⁰Cf*, E(cm)=84.9 MeV; ²⁰⁸Pb(³²S, X)²⁴⁰Cf*, E(cm)=149.9 MeV; ¹⁹⁸Pt(⁴⁰Ca, X)²³⁸Cf*, E(cm)=188.7 MeV; ¹⁹²Os(⁴⁸Ti, X)²⁴⁰Cf*, E(cm)=195.0 MeV; ²³⁸U(¹⁶O, X)²⁵⁴Fm*, E(cm)=103.5 MeV; ¹⁹⁶Pt(⁴⁸Ti, X)²⁴⁴Fm*, E(cm)=193.3 MeV; ²⁰⁸Pb(⁴⁰Ca, X)²⁴⁸No*, E(cm)=190.2 MeV; ²⁰⁰Hg(⁴⁸Ti, X)²⁴⁸No*, E(cm)=197.5 MeV; ¹⁸⁴W(⁶⁴Ni, X)²⁴⁸No*, E(cm)=252.3 MeV; ²³⁸U(²⁴Mg, X)²⁶²Rf*, E(cm)=129.3 MeV; ²³²Th(³⁰Si, X)²⁶²Rf*, E(cm)=144.0 MeV; ²⁰⁸Pb(⁴⁸Ti, X)²⁵⁶Rf*, E(cm)=210.6 MeV; ¹⁹²Os(⁶⁴Ni, X)²⁵⁶Rf*, E(cm)=239.2 MeV; ²³⁸U(²⁸Si, X)²⁶⁶Sg*, E(cm)=150.7 MeV; ²³²Th(³⁴S, X)²⁶⁶Sg*, E(cm)=166.7 MeV; ¹⁹⁸Pt(⁶⁴Ni, X)²⁶²Sg*, E(cm)=241.7 MeV; ²³²Th(⁴⁰Ca, X)²⁷²Ds*, E(cm)=211.5 MeV; ²⁰⁸Pb(⁶⁴Ni, X)²⁷²Ds*, E(cm)=259.5 MeV; ²³⁸U(⁴⁰Ca, X)²⁷⁸Cn*, E(cm)=210.7 MeV; ²³⁸U(⁴⁸Ti, X)²⁸⁶Fl*, E(cm)=214.6 MeV; measured reaction products using CUBE spectrometer of multiwire proportional counters (MWPCs), mass-angle distributions (MAD) at ANU's Heavy Ion accelerator facility; deduced systematic dependence of quasifission characteristics as a function of identity of colliding nuclei, entrance channel and compound nucleus fissilities, effects of nuclear structure at lower beam energies. Relevance to formation of superheavy elements.

doi: 10.1103/PhysRevC.88.054618