I wish to express to you all my sympathy following the death of your mother.
Your mother, Professor He Zehui, was a very bright scientist. She performed important research in Germany, including her study of elastic positron-electron scattering with a cloud chamber in W. Bothe's laboratory in Heidelberg. She then joined the Institut du Radium in Paris under the direction of Irène Joliot-Curie (1946). In Paris, she married your father Qian Sanqiang and discovered with him and two young French scientists, R. Chastel and L. Vigneron, in the laboratory of Frédéric Joliot-Curie, the fission of uranium in three and also four fragments (1947). In 1948 they went back to China and became very active in the development of nuclear physics in your country. She shared the life of your father in the recent history of China.
With my warm regards,