Eur. Phys. J. A (2013) 49: 147
https://doi.org/10.1140/epja/i2013-13147-y

Regular Article - Theoretical Physics

Main restrictions in the synthesis of new superheavy elements: Quasifission and/or fusion fission

¹ BLTP, Joint Institute for Nuclear Research, Joliot-Curie 6, 141980, Dubna, Russia
² Institute of Nuclear Physics, 100214, Tashkent, Uzbekistan
³ Rare Isotope Science Project, Institute for Basic Science, 305-811, Daejeon, Republic of Korea
⁴ Dipartimento di Fisica e di Scienze della Terra dell’ Università di Messina, Salita Sperone 31, 98166, Messina, Italy
⁵ Istituto Nazionale di Fisica Nucleare, Rome, Italy
⁶ Centro Siciliano di Fisica Nucleare e Struttura della Materia, 95125, Catania, Italy

Received: 12 September 2013
Revised: 17 October 2013
Accepted: 2 November 2013
Published online: 21 November 2013

Abstract

The synthesis of superheavy elements stimulates the effort to study the peculiarities of the complete fusion with massive nuclei and to improve theoretical models in order to extract knowledge about reaction mechanism in heavy-ion collisions at low energies. We compare the theoretical results of the compound nucleus (CN) formation and evaporation residue (ER) cross sections obtained for the ⁴⁸Ca + ²⁴⁸Cm and ⁵⁸Fe + ²³²Th reactions leading to formation of CN with A = 296 and A = 290 of the superheavy element Lv (Z = 116 , respectively. The ER cross sections, which can be measured directly, are determined by the complete fusion and survival probabilities of the heated and rotating CN. Those probabilities cannot be measured unambiguously but the knowledge about them is important to study the formation mechanism of the observed products and to estimate the ER cross sections of the expected isotopes of elements. To this aim, the ⁴⁸Ca + ²⁴⁹Cf and ⁶⁴Ni + ²³²Th reactions are considered too. The use of the mass values of superheavy nuclei calculated in the framework of the macroscopic-microscopic model by the Warsaw group leads to smaller ER cross section for all of the reactions in comparison with the case of using the masses calculated by P. Möller et al..