From a Yunnan mountain to a Tibetan highland——the story of a hundred years of cosmic ray research in China

The discovery of cosmic rays a hundred years ago opened a new field of view to the universe and the mysterious particle world，leading to the birth of particle physics. Cosmic ray research in China was started in the early 50’s of the last century by several senior scientists who had already distinguished themselves abroad in this subject. The first cosmic ray observatory in China was built on a mountain in Yunnan province，and many high level results were obtained in the ensuing ten years. Then after almost twenty years of political unrest，the national“Reform & Opening up”policy provided a good opportunity to stimulate development and to narrow the wide gap caused by long term stagnation. The second generation of Chinese cosmic ray researchers chose high altitude extensive air showers as their new target of observation，and embarked on twenty years of hard work to build a modern international cosmic ray experimental station at Yangbajing in Tibet，4300m above sea level. The manually operated cloud chamber was transformed into a large-scale high-technology facility，capable of performing various international research programs with its unique low threshold energy，high trigger rate and wide field of view. The Yanbajing Observatory symbolizes that China’s cosmic ray research has started on a new march towards excellence.