Subjects: Physics >> Nuclear Physics submitted time 2024-02-06
Abstract: Recently, an inelastic scattering experiment of 16O + 12C was performed at the Beijing Tandem Accelerator Nuclear Physics National of China Institute of Atomic Energy. New evidence for the existence of Bose-Einstein condensation state of 16𝑂 has been obtained. Employing a series of double-sided-silicon-strip-based telescopes, this experiment achieved accurate particle identification and coincidence measurement of 4-𝛼 in the decay of 16O for the first time. Based on this, high-resolution reaction 𝑄-value spectra was obtained and clear 4-𝛼 resonance states were reconstructed. In the vicinity of the 4-𝛼 separation threshold, 4 highly significant (3 of them above 5𝜎) resonance states were observed, which decay to the characteristic pattern of 12C(Hoyle state) + 𝛼, consistent with the predicted Hoyle-BEC structure and its rotating band features. The observation results will promote further theoretical research, and more measurements are needed for these resonance states in experiments.