The Jinping Underground experiment for Nuclear Astrophysics (JUNA) has leveraged the ultralow background of the CJPL to conduct experiments aimed at directly studying crucial reactions occurring at relevant stellar energies during the evolution of stars. In 2020, JUNA successfully commissioned an mA level high current accelerator based on an ECR source, as well as BGO and $^3$He detectors....
In nuclear astrophysics, a crucial aspect is understanding the thermonuclear reactions that power the stars and lead to the synthesis of chemical elements. At astrophysical energies, the cross section of nuclear processes is significantly reduced by the Coulomb barrier, making direct measurements challenging. In addition, the low value of cross sections often hinders their measurement on...
Direct measurements of the cross sections for the radiative capture reactions ${}^{12,13}\mathrm{C}(\mathrm{p},\gamma){}^{13,14}\mathrm{N}$ at energies of astrophysical interest are challenging, due to the rapidly falling cross sections towards lower energies, and for the absence of narrow resonances at low proton energies required for target characterization. The two reactions have been...
The reactions 22Ne(a,n)25Mg and 22Ne(a,g)26Mg are of high importance for the formation of heavy elements in the weak s process, main s process branchings and strongly influence the Mg isotopic ratios that we can directly observe in stellar atmospheres. For an accurate astrophysical modeling, both reaction cross sections need to be known at energies far below the Coulomb barrier, where direct...
The interplay and correlation between the $^{22}$Ne$(\alpha,\gamma)^{26}$Mg and the competing $^{22}$Ne$(\alpha,n)^{25}$Mg reaction determines the efficiency of the $^{22}$Ne$(\alpha,n)^{25}$Mg reaction as a neutron source for the weak $s$-process. In both cases, the reaction rates are dominated by the strength of the $\alpha$ cluster resonance at 830 keV. This plays a particularly important...
The $^{13}$C($\alpha$,n)$^{16}$O reaction is the main neutron source for the slow-neutron-capture (s-) process in Asymptotic Giant Branch stars and for the intermediate (i-) process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray induced background. We performed the first consistent direct...
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20-kton liquid scintillator detector currently under construction in an underground laboratory in South China. It is expected to complete detector construction by the end of 2023. With excellent energy resolution, a large detector volume and superb background control, JUNO will become a flagship experiment in the coming decades. Its...
