Triple α -particle resonances in the decay of hot nuclear systems *

Abstract

The Efimov (Thomas) trimers in excited 12 C nuclei, for which no observation exists yet, are discussed by means of analyzing the experimental data of 70(64) Zn( 64 Ni) + 70(64) Zn( 64 Ni) reactions at beam energy of E/A=35 MeV/nucleon. In heavy ion collisions, the αs interact with each other and can form complex systems such as 8 Be and 12 C. For the 3α systems, multi resonance processes give rise to excited levels of 12 C. The interaction between any two of the 3α particles provides events with one, two or three 8 Be. Their interfering levels are clearly seen in the minimum relative energy distributions. Events of three couple α relative energies consistent with the ground state of 8 Be are observed with the decrease of the instrumental error at the reconstructed 7.458 MeV excitation energy of 12 C, which was suggested as the Efimov (Thomas) state.

Four α correlations in nuclear fragmentation: a game of resonances *

“…This mechanism has been observed in atoms [44] for three particles, and a possible extension to N 3 boson systems is currently investigated [43]. On the other hand, similar to the situation for 12 C [35,36], we expect an excited level of 16 O, which decays sequentially to 12 C(HS)+ with 12 C(HS) decaying into 8 Be+ [45][46][47][48]. In this case the available excitation energy is not divided 'democratically' (equally) among all the particles.…”

“…In Refs. [35,36], we have extended the study of 12 C to 'in medium ' decays by studying three correlations for 70 Zn+ 70 Zn, 64 Zn+ 64 Zn, and 64 Ni+ 64 Ni heavy ion collisions at 35 MeV/u; the corresponding experiment was performed at the Cyclotron Institute, Texas A&M University [32]. Following Refs.…”

Dipole excitation of $^6$Li and $^9$Be studied with an extended quantum molecular dynamics model

“…The phenomena of α-clustering structure in light nuclei have been investigated by lots of experiments and theories for a few decades, it is not only of importance to understanding effective nucleon-nucleon interaction inside nuclei, but also help to learn their important roles during the nucleosynthesis processes [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16].…”

Network structure of thermonuclear reactions in nuclear landscape

“…Much attention has been paid earlier on topics like the exploration up to limits of the nuclear landscape and searching for the island of stability [16][17][18][19][20][21][22][23]. The terrestrial nuclear reaction experiments provide a large volume of data for thermonuclear reaction rates (mainly on stable targets), based on which many theoretical models have been developed to calculate the binding energy of different nuclides and the cross-sections and reaction rates for different nuclear processes [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42]. The JINA REACLIB database is a well-known source of thermonuclear reaction rates [43], updated continuously and snapshotted regularly by the JINA Collaboration which aims to compile a complete set of nuclear reaction rates.…”