Progress of the Ground Experiments of Jinping Underground Nuclear Astrophysics Experiment

A number of nuclear reactions such as ^25\rmMg(\rmp,\gamma )^26\rmAl, ^13\rmC(\alpha ,\rmn)^16\rmO, ^12\rmC(\alpha ,\gamma )^16\rmO and ^19\rmF(\rmp,\alpha )^16\rmO will be measured directly down to the Gamow window energy range in Jinping Underground Nuclear Astrophysics (JUNA) Experiment, taking the advantage of the ultra-low background in China Jinping Unerground Laboratory (CJPL). The measurements can provide updated data for understanding the evolution of stars and the origin of elements. Up to now, tests of accelerator, beam, targets, detectors, and electronics have been performed systematically on the ground. The high-purity germanium detectors efficiency calibration, 304 keV resonance strengths measurement in ^25\rmMg(p, \rm\gamma)²⁶Al, ^19\rmF(\rmp,\alpha )^16\rmO cross section measurement, neutron detector design, production and efficiency calibrationas as well as target design and stability test are included as overground experiments. The Whole JUNA project is going smoothly in general. A series of key progresses and primary results have been reached on the ground. Underground experiments in the JUNA project will be carried out in order and reach the prospected goals in the near future. Broader international cooperation will also be promoted, supporting the solution of several major scientific problems in the evolution of cosmogony.