Wang Ganchang

Wang Ganchang
王淦昌

Wang Ganchang
Born May 28, 1907
Changshu, Jiangsu Province, Qing dynasty China
Died December 10, 1998(1998-12-10) (aged 91)
Beijing, People's Republic of China
Residence China
Germany
USSR
Nationality Chinese
Fields Nuclear physics
Institutions

Qinghua University
Shandong University
Zhejiang University
Luoxue Mountain Cosmic Rays Research Center
Institute of Modern Physics
Joint Institute for Nuclear Research
Chinese nuclear weapons program
Ninth Research Institute
China Engineering Physics Research Institute
Institute of Atomic Energy


Nuclear industry Science and Technology Commission
China Association for Science and Technology
Chinese Physical Society
China Nuclear Society
NPC Standing Committee
Alma mater Qinghua University
University of Berlin
Doctoral advisor Lise Meitner
Known for anti-sigma minus hyperon
Influenced Frederick Reines
Notable awards JINR Prize (1961)
National Natural Science Award (1982)
National Science and Technology Progress Award (1985)
Two Bombs and One Satellite Meritorious Award (1999)

Wang Ganchang (Chinese: 王淦昌; pinyin: Wáng Gànchāng; Wade–Giles: Wang Kan-ch'ang) (May 28, 1907 – December 10, 1998) was a nuclear physicist from China. He was one of the initiators of research in China in nuclear physics, cosmic rays and particle physics. Wang figured among the top leaders, pioneers and scientists of the Chinese nuclear deterrent program. He was a member of the Chinese Academy of Science and a member of the Chinese Communist party.

In 1930, Wang first proposed the use of a cloud chamber to study a new type of high-energy ray induced by the bombardment of beryllium with α particles, an experiment conducted one year later by the English physicist James Chadwick, who thus discovered a new type of particle, the neutron, for which he won the 1935 Nobel Prize in Physics.

Wang first proposed the use of beta-capture to detect the neutrino in 1941.[1] James Allen employed his suggestion and found evidence for the existence of the neutrino in 1942. Frederick Reines and Clyde Cowan detected the neutrino via the inverse beta-decay reaction in 1956, for which, forty years later, they were awarded the 1995 Nobel Prize in Physics.

Wang also led a group to discover the anti-sigma minus hyperon particle at Joint Institute for Nuclear Research, Dubna, Russia in 1959.[2]

After May 1950, Wang became researcher and vice-director of the Institute of Modern Physics (中国科学院近代物理研究所). He was vice-director of the Soviet Joint Institute for Nuclear Research. From spring 1969, he was vice-director of the Ninth Research Institute (二机部第九研究院), predecessor of the China Academy of Engineering Physics. He was director of the China Institute of Atomic Energy (二机部副部长兼原子能研究所). He was deputy director of the Nuclear industry Science and Technology Commission (核工业部科技委). He was second vice-chairman of the China Association for Science and Technology. He was vice-chairman of the Chinese Physical Society (中国物理学会). He was first chairman of the Chinese Nuclear Society (中国核学会). He was a member of the 3rd through 16th National People's Congress Standing Committees of the Chinese government.

In 2000, the Chinese Physical Society established five prizes in recognition of five pioneers of modern physics in China. The Wang Ganchang Prize is awarded to physicists in particle physics and inertial confinement fusion.

Early years

Wang Ganchang was born in Changshu County, Jiangsu Province (江苏省常熟县支塘镇枫塘湾), on May 28, 1907.[3] In 1924, he graduated from the Pudong High School (上海浦东中学) in Shanghai. He then studied English for six months and car driving and repair for six months. He passed the entrance examinations for Qinghua University in August 1928.

He graduated from the Physics Department of Qinghua University in June 1929. He was an assistant professor at Qinghua University from 1929 to 1930. In his thesis "On the daily change of radon gas" (《清华园周围氡气的强度及每天的变化》), he was the first Chinese to publish on atmospheric research and radioactive experiments.[4]

Overseas student in Germany

In 1930 he went to study at the University of Berlin in Germany. As soon as he arrived in Berlin, he heard the Bothe report (博特报告) relating to the emission of a new type of high-energy neutral radiation induced by the bombardment of beryllium with α particles from a radioactive polonium source, which was non-ionizing but even more penetrating than the strongest gamma rays derived from radium. These were therefore (but wrongly, as it turned out) presumed to be gamma rays. Wang suggested the use of a cloud chamber to study these particles. This was not done in Germany, as Wang lacked the support of his supervisor Lise Meitner, but the experiment was nonetheless conducted one year later by the English physicist James Chadwick, who thus discovered a new type of particle, the neutron, for which he won the 1935 Nobel Prize in Physics.

In 1934, Wang Ganchang received his Ph.D. with a thesis on β decay spectrum (German: Über die β-Spektren von ThB+C+C; Chinese:《ThB+C+C的β能谱》) under the supervision of Meitner before returning to China in April of that year.[5]

Return to China

He first worked at Shandong University as a physics professor from 1934 to 1936 before becoming a professor at Zhejiang University and serving as head of the Department of Physics there from October 1936 to 1950.

The WW II years

Following the Marco Polo Bridge Incident in July 1937, Professor Wang Ganchang was forced by the Japanese full-scale invasion of China to retreat with all the faculty of Zhejiang University to the western mountainous hinterland of China.

Despite the difficult conditions, he nonetheless tried in 1939 to find on photographic films tracks of nuclear fission caused by neutron bombardment of cadmium acid.

In 1941, he first proposed an experiment to prove the existence of the neutrino by capturing K-electrons in nuclear reactions. Unfortunately, he was unable to conduct the experiment because of the war. Fifteen years later, in 1956, Frederick Reines and Clyde Cowan detected the neutrino via the inverse beta-decay reaction in 1956, for which, forty years later, they were awarded the 1995 Nobel Prize in Physics. It should be noted, however, that the suggested technique of Prof Wang is only remotely related to the Reines, Cowan neutrino experiment. Reactor neutrinos and the inverse beta reaction were used by Reines and Cowan, not a radioactive substance and K-Capture.

Early People's Republic of China years

From April 1950 to 1956 Wang was a researcher at the CAS Institute of Modern Physics and served as deputy director from 1952. There, at the invitation of Qian Sanqiang of the Institute of Modern Physics, he started studies of cosmic-rays with a circular 12 feet cloud chamber. In 1952, he designed a magnetic cloud chamber.

Professor Wang was the first to propose the establishment of a cosmic ray laboratory in China. Subsequently, he directed the Luoxue Mountain Cosmic Rays Research Center (落雪山宇宙线实验站) in the Yunnan province high mountainous regions at 3185 meters above sea level from 1953 to 1956.

His study of cosmic-rays lead him to publish his findings on neutral-meson decay in 1955. By 1957 he had collected more than 700 recordings of new types of particles.

The USSR years

In order to develop high energy physics in China, the Chinese government began from 1956 to send some experts to the Joint Institute for Nuclear Research at Dubna in the USSR to do field work and carry out the preliminary design of particle accelerators. The agreement on the establishment of JINR was signed on March 26, 1956 in Moscow, Wang Ganchang being one of the founders.[6]

On April 4, 1956, Wang went to the USSR to participate in planning the long-range development of peaceful utilization of atomic energy. Later, many Chinese students went to the (then) Soviet Union to learn the technology of accelerator and detector construction. Using this technology, the experimental group led by Professor Wang Ganchang in Dubna analysed more than 40,000 photographs which recorded tens of thousands of nuclear interactions taken in the propane bubble chamber produced by a 10 GeV synchrophasotron used to bombard a target forming high energy mesons, and on March 9, 1959:[7] they were the first to discover the anti-sigma minus hyperon particles (反西格马负超子)

\pi^- + C\to \bar\Sigma^- + K^0 + \bar K^0 + K^- + p^+ + \pi^+ + \pi^- + nucleus~~~recoil

The discovery of this new unstable antiparticle which decays in (1.18±0.07)·10−10 s into an antineutron and a negative pion was announced in September of that year:[5]

\bar\Sigma^-\to \bar n^0 + \pi^-

No one doubted at the time that this particle was elementary, but a few years later, this hyperon, the proton, the neutron, the pion and other hadrons had lost their status of elementary particles as they turned out to be complex particles too consisting of quarks and antiquarks.

He served as deputy director of the Joint Institute for Nuclear Research from 1958 until 1960, when he returned to China.

Nuclear weapons

After his return from the USSR, he agreed to participate in the Chinese atomic bomb program, giving up research on elementary particles for the next 17 years. Within one year, he conducted more than 1000 detonation experiments at the foot of the Great Wall, in the Yanshan Mountain (河北省怀来县燕山), Huailai county, Hebei province.

In 1963 he moved to the Qinghai Plateau at more than 3000 meters, to continue polymerization detonation experiments. He then proceeded to Xinjiang's scorching Taklimakan desert to make preparation for the first nuclear test. Finally on October 16, 1964 the first atomic bomb test was conducted successfully. Less than three years later, on June 17, 1967 the first hydrogen bomb test was conducted with success, shocking the world as China mastered this technology even before the French, and thus broke the nuclear monopoly of the two superpowers.

In spring 1969, Wang served as vice-director of the Ninth Research Institute (二机部第九研究院) receiving the task of conducting the first underground nuclear test. Due to severe high altitude hypoxia, he had to carry an oxygen mask at work. The first underground test was successfully conducted on September 23, 1969. He also led the second and third Chinese underground nuclear tests.

Nuclear fusion and nuclear energy

Wang Ganchang is the founder of Chinese laser fusion technology. In 1964 the CAS Shanghai Optical Machinery Institute (中国科学院上海光学精密机械研究所) developed a high-power 10 MW output laser. In late December of the same year, he proposed to the State Council using high-power laser beam targeting to achieve inertial confinement fusion, idea also independently developed at the same time by his Soviet counterpart Nikolai Gennadievich Basov. Unfortunately, due to political turmoil causing seven years of delay, his leading position in this field was lost.

By the end of 1978, his inertial confinement fusion research group established by the Atomic Energy began the construction of a high-current accelerator. As an advocate of nuclear energy, with four other nuclear experts in October 1978, Wang proposed the development of nuclear power in China. In 1980, he promoted a plan to build 20 nuclear power plants including Qinshan, Zhejiang Province, Daya Bay, Guangzhou and Chinshan.

Project 863: laser and electromagnetic pulse weapons

Wang was also a leader in the fields of detonation physics experiments, anti electromagnetic pulse technologies, nuclear explosion detection, anti nuclear radiations technologies, laser stimulated nuclear explosion technologies.

On March 3, 1986, Wang Ganchang, Wang Daheng, Yang Jiachi and Chen Fangyun first proposed in a letter (《关于跟踪世界战略性高科技发展的建议》) to the Chinese government to launch research covering lasers, microwaves, and electromagnetic pulse weapons. The plan would be adopted in November of that year under the code name Project 863 (“863计划”).[8]

Awards

Wang was the first recipient of the National Natural Science Award (国家自然科学奖) in 1982. He was the first recipient of the National Science and Technology Progress Award (国家科技进步奖特等奖) in 1985. In September 1999, he received jointly with Qian Sanqiang (both posthumously) the special prize of Two Bombs and One Satellite Meritorious Award (两弹一星功勋奖章) granted by the State Council, the Central Committee of the Communist Party and Central Military Commission .

See also

Selected literature by Wang Ganchang

German (as K. C. Wang)
English (as K. C. Wang)
English (as G. Wang)
Chinese (as 王淦昌)
Russian (as Ван Ган-чан )

References

  1. ↑ "A Suggestion on the Detection of the Neutrino". Physical Review. Retrieved 2007-08-17.
  2. ↑ "JOINT INSTITUTE FOR NUCLEAR RESEARCH".
  3. ↑ "王淦昌辉煌人生". 国防科学技术工业网. 2007-05-24. Retrieved August 1, 2008.
  4. ↑ "王淦昌". 中基网. 2001-11-08. Retrieved August 7, 2008.
  5. 1 2 "王淦昌的科学贡献". 电动力学网络教程. 2006-06-01. Retrieved August 4, 2008.
  6. ↑ "International Intergovermental Organization Joint Institute for Nuclear Research" (PDF). Laboratory of High Energies of the Joint Institute for Nuclear Research. July 18, 2008. Retrieved August 12, 2008.
  7. ↑ "50th Anniversary of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research" (PDF). Laboratory of High Energies of the Joint Institute for Nuclear Research. October 27, 2003. Retrieved August 11, 2008.
  8. ↑ "1998年12月10日物理学家王淦昌逝世". 无锡阿福台网. October 27, 2005. Retrieved August 7, 2008.

External links

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