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Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.

Based on the angular distribution of the 8Li(d,n)9Beg.s. reaction at Ec.m. = 8.0 MeV and distorted wave Born approximation analysis, the single particle spectroscopic factor S1,3/2 for the ground state of 9Be = 8Li⊗p is derived to be 0.64 ± 0.21. In addition, we deduce the astrophysical S-factors and rates of the 8Li(p,γ)9Beg.s. direct capture reaction at energies of astrophysical interests.

The angular distribution of the 2H(8Li, 9Be)n (ground state) reaction, important to primordial nucleosynthesis in the inhomogeneous model, has been measured at Ec.m. = 8.1 MeV using a secondary 8Li beam. Cross section of this reaction was determined to be 9.0±3.4 mb. According to the cross section, the astrophysical S-factor was calculated to be 272±103 keV b. It is shown that 2H(8Li, 9Be)n (ground state) reaction is important for creating 9Be, but less important for destroying 8Li in primordial nucleosynthesis.

Angular distribution of the 6He(d,n)7Li reaction at Ec.m.=9.1 MeV is measured in inverse kinematics for the first time. The proton spectroscopic factors for the ground and first excited states of 7Li are derived by using the distorted wave Born approximation analysis. The astrophysical rates of 6He(p, ?)7Li reaction are then deduced and fitted with an expression of REACLIB.

The elastic resonance scattering of 17F+p is studied in inverse kinematics via a thick-target method. The excitation function for 17F+p elastic scattering is obtained within the energy interval of Ec.m. ~ 0.4–1.7 MeV. The experimental excitation function is analyzed with a multilevel R-matrix code MULTI7, and the proton widths are deduced. The α decay from 6.15 MeV 1− state in 18Ne is observed, which is critical to the 14O(α, p)17 F reaction as the main breakout route from CNO cycle to rp-process in supernovae and x-ray bursts.

Angular distribution of the 12C(6He, 7Li)11B transfer reaction is measured with a secondary 6He beam of 36.4 MeV for the first time. The experimental angular distribution is well reproduced by the distorted-wave Born approximation (DWBA) calculation. The success of the present experiment shows that it is feasible to measure one-nucleon transfer reaction on a light nucleus target with the secondary beam facility of the HI-13 tandem accelerator at China Institute of Atomic Energy (CIAE), Beijing.