Experimental measurement of the ¹²C+¹⁶O fusion cross sections at astrophysical energies

¹ Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, Zhuhai, Guangdong 519082, China
² Institute for Structure and Nuclear Astrophysics, Joint Institute for Nuclear Astrophysics, University of Notre Dame, Notre Dame, Indiana 46556, USA
³ Department of Chemistry, Indiana University Bloomington, Bloomington, Indiana 47405, USA
⁴ Institute of Modern Physics, Chinese Academy of Science, Lanzhou, Gansu 730000, China
⁵ Texas A&M University, College Station, Texas 77843, USA

^* e-mail: fangx26@mail.sysu.edu.cn

Published online: 16 May 2018

Abstract

The total cross sections of the ¹²C+¹⁶O fusion have been experimentally determined at low energies to investigate the role of this reaction during late stellar evolution burning phases. A high-intensity oxygen beam was produced by the 5MV pelletron accelerator at the University of Notre Dame impinging on a thick ultra-pure graphite target. Protons and γ-rays were measured simultaneously in the center-of-mass energy range from 3.64 to 5.01 MeV, using strip silicon and HPGe detectors. Statistical model calculations were employed to interpret the experimental results. A new broad resonance-like structure is observed for the ¹²C+¹⁶O reaction, and a decreasing trend of its S-factor towards low energies is found.