He Zehui, born on March 5, 1914, in Suzhou, hailing from Lingshi, Shanxi Province. His father, He Cheng, harbored the "dream of a strong nation" and studied in Japan early on, being a member of the same alliance as Dr. Sun Yat-sen, and was also a renowned connoisseur and collector. His educational philosophy for his children was "scientific, free, equal, and independent," emphasizing precision in technology, clarity in affairs, and kindness towards people. His mother, Wang Jishan, came from the Wang family in Suzhou. His maternal uncle, Wang Jilie, became a Jinshi scholar in the last imperial examination in China but valued Western learning and authored the first set of "Physics" in China. His maternal grandmother, Wang Xiechangda, founded the renowned Zhenhua Girls' School in Suzhou, which was continued by his third aunt, Wang Jiyu, advocating modern scientific culture. He Zehui was influenced by both paternal and maternal progressive and enlightened upbringing from a young age.
In 1920, He Zehui entered Zhenhua Girls' School, where she studied for twelve years, from elementary to high school. She received comprehensive development in morality, intelligence, physical education, arts, and calligraphy, and also laid a solid foundation in mathematics, physics, and English.
In 1932, He Zehui was admitted to the Physics Department of Tsinghua University. Among the 28 new students, there were 8 female students. The head of the department, Ye Qisun, perhaps concerned about the difficulty of female students studying physics, attempted to persuade them to switch departments. This infuriated He Zehui, who grew up in an environment of gender equality and women's rights advocacy at Zhenhua Girls' School. She stood up and, along with her female classmates, argued with Ye Qisun: "Why did you set a gender condition beyond the examination results? It wasn't mentioned during enrollment!" Ye Qisun was speechless when questioned and eventually had to allow female students to stay on par with male students. After several rounds of eliminations, only 10 out of the initial 28 students remained, including three female students, including He Zehui. She fought for the rights of gender equality and ultimately graduated with a score of 90 on her thesis, "Stabilized Current for Laboratory Use," tied for first place with Qian Sanqiang. Seventy-four years later, at the 80th anniversary celebration of the founding of the Department of Physics at Tsinghua University in 2006, He Zehui, hospitalized due to a broken leg, sent a video to attend the meeting and conveyed a message: "Hope that the Department of Physics at Tsinghua University will continue to improve, advocating for gender equality," even while sick, she continued to speak up for gender equality.
In 1936, He Zehui chose to pursue a doctoral degree in Germany. Out of patriotism and anti-Japanese fervor, she resolutely chose the specialty of "experimental ballistics" in the Department of Technical Physics at the Berlin Institute of Technology. However, she was rejected because the Department of Technical Physics' specialty in ballistics was closely related to the German military industry and had never accepted foreign students before, let alone female students. Determined to study ballistics, He Zehui approached Professor Krantz, the head of the Department of Technical Physics, who had previously served as a consultant to the Nanjing Arsenal, and requested admission to this specialty. Initially, Professor Krantz refused, so He Zehui said to him, "You can come to China to serve as a consultant to our Nanjing Arsenal and help us fight the Japanese invaders. I came here to study this specialty to fight against the Japanese invaders. Why won't you accept me?" Professor Krantz felt that He Zehui made sense and agreed to let her try. He Zehui broke two precedents: the Department of Technical Physics did not admit foreign students, and the ballistics specialty did not admit female students, once again winning the right to gender equality.
In 1940, He Zehui obtained her doctoral degree with a thesis titled "A New and Precise Method for Measuring the Velocity of Bullet Flight." Due to World War II, He Zehui could not return to China. She then joined the weak current laboratory of Siemens AG in Berlin. There she met John Rabe, the chairman of the International Committee of the Safety Zone in Nanjing and the head of Siemens AG in China. Rabe showed her the photos of Japanese atrocities he had collected, making her a witness to this historic act. These photos filled her with mixed emotions of sadness, anger, and determination. She was determined to return to China to serve her country.
In 1943, He Zehui was introduced by German physicist Professor Parvin to the Nuclear Physics Research Institute of the Royal William Academy in Heidelberg, where she conducted experimental research on nuclear physics under the guidance of Nobel Prize-winning physicist Porter.
In 1945, while studying positron energy spectra, He Zehui discovered an almost entirely exchange of energy without annihilation phenomenon, resembling an S-shaped trace. She sent the photos to Qian Sanqiang, who was then at the Curie Laboratory at the University of Paris in France. Qian Sanqiang projected He Zehui's S-shaped trace photo at the Anglo-French Cosmic Ray Conference, arousing great interest among the participants. On November 3, 1945, the British journal Nature called Dr. He's discovery "a scientific rarity."
In April 1946, He Zehui married Qian Sanqiang in France. Since then, He Zehui also conducted nuclear physics research at the French Academy of Sciences Atomic Chemistry Laboratory and the Curie Laboratory, beginning a joint scientific research career with Qian Sanqiang.
In the latter half of 1946, Qian Sanqiang and He Zehui discovered the phenomenon of uranium nucleus undergoing three-way fission under neutron bombardment. On November 20, 1946, He Zehui discovered the first quadruple forked event, and in February of the following year, she discovered the second quadruple forked event. This was a more difficult-to-find four-way fission phenomenon. This discovery was announced at an international scientific conference convened by Joliot-Curie in Paris.
The three-way and four-way fission phenomena of uranium nuclei are considered significant achievements in physics after World War II and caused a huge stir in the international scientific community upon their announcement. Qian Sanqiang and He Zehui were awarded the Henry DePaville Physics Scholarship in France, and Western media referred to them as "China's Curie Couple."
Despite their significant achievements in scientific research, He Zehui and Qian Sanqiang did not forget their original intention to study abroad and decided to return to their homeland, along with other scientists, to establish the roots, blossom, and fruition of the emerging discipline of nuclear physics in their homeland.
On May 1, 1948, He Zehui and Qian Sanqiang, accompanied by their less-than-six-month-old daughter, left France In 1950, Mr. He Cheng and his eight children jointly donated the Suzhou Wangshi Garden, which their father had spared no effort to protect and renovate during his lifetime, to the country; in 1990, they donated Mr. He Cheng's collection of seventy-two precious seals and seal materials to the country. The two donations from the He family included 31 first-level national cultural relics and 12 precious ink treasures. In 1997, Wangshi Garden, one of the four famous gardens in Suzhou, was listed on the UNESCO World Heritage List for Cultural and Natural Heritage Protection.
Since February 1950, He Zehui has been guiding and personally conducting research on the development of atomic nucleus latex, Wilson cloud chambers, electron amplifiers, and methods for the separation of heavy elements.
In January 1955, a decision was made at the expanded meeting of the Central Secretariat chaired by Chairman Mao Zedong to develop China's atomic energy industry. Neutrons are the key to using atomic energy, but the experimental neutron physics research in China was almost nonexistent.
In October 1955, General Qian Sanqiang led the "Thermal Engineering Internship Group" to visit the Thermal Engineering Research Institute in the Soviet Union; in November, as one of the deputy group leaders, Mr. He Zehui went to the Soviet Union for the second time. She was responsible for understanding the nuclear physics experiments conducted on accelerators and reactors and personally conducted experimental research on the cyclotron.
In 1956, after more than 420 experiments, latex detectors sensitive to protons, α particles, fission fragments, etc., were successfully developed, including nuclear-2 and nuclear-3 for detecting slow neutrons, as well as nuclear-2 loaded with boron and nuclear-2 loaded with lithium, with performance levels comparable to those of the C-2 produced by ICI in the UK. He Zehui and her collaborators Lu Zuyin and Sun Hancheng won the 1956 Award of the Chinese Academy of Sciences (Natural Sciences Section) for their work on "Research on the Preparation Process of Atomic Nucleus Latex," which was the third prize in the first National Natural Science Award.
In September of the same year, the Neutron Physics Laboratory (Second Laboratory) was established at the Institute of Physics of the Chinese Academy of Sciences (formerly the Institute of Atomic Energy). Its research content began to cover neutron physics, reactors, accelerators, electromagnetic separators, detectors, electronics, etc. Later, other fields were separated successively, and the Second Laboratory retained only neutron physics. General Qian Sanqiang served as the director and concurrently as the director of the laboratory, while He Zehui served as the deputy director. In July 1958, Mr. He officially became the director of the Second Laboratory.
When the Second Laboratory was established in 1956, the foundation for neutron experiments was very weak. The entire equipment left by the institute for neutron experiments included the nuclear latex developed under He Zehui's leadership, the counting tubes led by Dai Chuansong, and the high-voltage multiplier developed under Yang Chengzhong's leadership. After eight years of effort, He Zehui established a relatively complete neutron physics laboratory for China based on this weak foundation.
First, a relatively complete neutron source covering neutron energies from thermal neutrons (0.0253 electron volts) to 18 mega-electron volts was established.
Second, a relatively complete method for measuring neutron cross-sections was established. Dai Chuansong led Zhang Huanqiao, Ye Chuntang, etc., to build a crystal spectrometer, Qian Sanqiang led Xiang Zhilin, Wang Naiyan, Wu Zhihua, Niu Shiwen, etc., to build a slow neutron mechanical selector spectrometer, and He Zehui led Yang Zhen, Gong Linghua, Wang Dahai, etc., to establish a slow neutron time-of-flight spectrometer on the cyclotron. With these spectrometers, neutron cross-section measurements can be performed within the energy range of 0.001-1 kilo-electron volts. Qian Sanqiang led Huang Shengnian, Wang Yusheng, Ye Zongyuan, etc., to establish experimental techniques such as fission chambers, boron trifluoride (BF3) neutron counters, and electroplated uranium foils, which can be used for measurements such as fission yield, fission cross-section, and prompt neutron number and distribution of fission. Zhou Delin, Wang Dahai, Lu Hanlin, etc., established the activation method, which can be used for measurements of some nuclear reaction excitation curves. He Zehui led Gu Yifan, etc., to establish a millisecond (nanosecond) fast neutron time-of-flight spectrometer on the cyclotron, which can be used for measurements of total cross-sections, elastic and inelastic scattering cross-sections, etc.
Third, various methods for measuring neutron energy spectra were established, mainly using the millisecond time-of-flight method, supplemented by methods such as nuclear latex, organic crystal and liquid scintillation recoil proton methods, threshold detector methods, lithium foil semiconductor sandwich methods, and multi-sphere methods, which were established successively in the process of completing different tasks.
Fourth, standards for neutron fluxes in multiple energy ranges were established. Early standards were established for thermal neutrons (0.0253 electron volts) and fast neutrons (14.1 mega-electron volts). After 1963, Ye Chuntang was arranged to establish standards for neutron source intensity, and Gong Linghua was arranged to establish standards for partial monoenergetic neutron fluxes.
Fifth, a rigorous and pragmatic scientific research style was established, cultivating a team with strong professional capabilities, solid work ethics, and the ability to tackle tough challenges.
The Neutron Physics Laboratory led by He Zehui not only established experimental techniques for neutron physics and fission physics research from scratch and pioneered research in neutron physics and fission physics foundations but also provided many important nuclear data for China's nuclear weapons development.
In January 1958, the Ninth Bureau of the Third Ministry of Machine-Building (renamed the Ninth Bureau of the Second Ministry of Machine-Building in February 1958, and also known as the Ninth Institute after July, later known as the Ninth Academy) responsible for the development of nuclear weapons was established. He Zehui made many foundational contributions to the establishment of experimental nuclear physics at the Ninth Academy's nuclear weapons base and also completed many important tasks assigned by the Ninth Academy.
Firstly, He Zehui organized and arranged the training of dozens of scientific research personnel for the Ninth Academy. At that time, two new groups were set up in the Second Laboratory, Group 27 and Group 28, specifically for training interns from the Ninth Academy. Group 27 was led by Hu Renyu from the Ninth Academy, with Lu Zuyin from the Second Laboratory as the deputy leader, engaged in the development and operation of fast neutron generators, while Tang Xiaowei and others from the Ninth Academy used the cyclotron for fast neutron measurements and experimental research. Group 28 was led by Lai Zuwu from the Ninth Academy, with Wu Dangshi from the Second Laboratory as the deputy leader, engaged in subcritical experiments with nuclear materials. In addition to helping train scientific research personnel, He Zehui also sent many technical elites to the Ninth Academy He Zehui also cooperated to complete multiple nuclear test tasks and provided many nuclear test measurement devices, such as nuclear emulsions, solid-state track detectors, and small fission chambers, helping to solve some important technical problems in on-site testing of nuclear weapons.
In summary, the Second Department led by He Zehui provided a series of crucial nuclear data, experimental equipment, and experimental methods for the development of nuclear weapons.
In addition, He Zehui also established a special team in the Second Department to assist in the development of nuclear submarines, conducting extensive experimental work on neutron and γ-ray shielding for nuclear submarines.
In 1965, He Zehui personally led the completion of the top-secret urgent task #35. She led dozens of scientists and technicians to work day and night, completing the measurement of cross-section data for six reaction channels of incident particles with energies ranging from 20 keV to 600 keV and two light nuclei, 6Li and 7Li, in less than half a year, a task that would normally take two to three years to complete. The measured data clarified the confusion in the existing data at that time and played an important role in the early selection of hydrogen bomb technology approaches in China.
During the "Cultural Revolution" which began in 1966, He Zehui was criticized, her office was ransacked, and she was relegated to a small room in a staircase corridor on the second floor of Building 53 at the Institute of Atomic Energy, where she was responsible for cleaning the toilets every day. However, she remained composed, responding to irrational questioning and criticism with silence.
On December 1, 1969, He Zehui was approved to work at the "Five-Seven Cadre School" in Heyang, Shaanxi, laboring alongside Mr. Qian Sanqiang for about two and a half years. Due to her relatively frail health, she was given light duties such as watching over fields, ringing bells, and monitoring water. When she rang the bell, she did so with the same seriousness and precision as conducting a scientific experiment; when she monitored the fields, she would not sit still but continuously patrol the area, making it impossible for pigs, chickens, cows, sheep, sparrows, or rats to approach. In late March 1970, around four or five o'clock in the morning, she even discovered a bright and beautiful comet in the northeastern sky and tracked its observation, calculating its approximate period. He Zehui's discovery came more than three months after the South African astronomer Bennett's discovery using a telescope, but hers was made with the naked eye. Even in such an environment as the cadre school, He Zehui never forgot about scientific research, using the vast sky as her experimental platform, demonstrating her steadfast pursuit of science.
In 1973, under the guidance of Premier Zhou Enlai, the Institute of High Energy Physics of the Chinese Academy of Sciences was established based on a department at the Institute of Atomic Energy, with He Zehui serving as deputy director. She focused on developing new scientific frontiers, leading interdisciplinary research, and promoting the initial development of cosmic ray ultra-high-energy physics and high-energy astrophysics research in China. With her advocacy and support, the Cosmic Ray Laboratory of the Institute of High Energy Physics built the highest-altitude (5500 meters) mountain emulsion chamber in the world through domestic and international cooperation at Mount Gambala in Tibet; she also spearheaded the development of China's high-altitude scientific balloons from scratch, which subsequently drove the development of space hard X-ray detection technology and other related technologies.
He Zehui was an internationally renowned nuclear physicist and high-energy physicist, and one of the founders of nuclear physics, high-energy physics, and high-energy astrophysics in China. She was elected as a member of the Mathematics and Physics Division of the Chinese Academy of Sciences in 1980. In 1997, she was awarded the Ho Leung Ho Lee Prize for Scientific and Technological Progress. She passed away in Beijing in June 2011.
He Zehui's life was one of patriotic dedication, steadfast pursuit of science, dedication to her work, and advocacy for gender equality. She was a female scientist who loved her country, revered science, respected her profession, and fought for gender equality.
The remarkable achievements and valuable spiritual wealth left by He Zehui on the path of scientific advancement will be recorded in the annals of human history, inspiring future generations to continue moving forward.
(This article is about to be published in "Modern Physics Knowledge")
(Original title: A Female Scientist Who Loves Her Country, Reveres Science, Respects Her Profession, and Fights for Gender Equality: Commemorating the 110th Anniversary of the Birth of He Zehui)
