Lead Tungstate Crystals from Dongsheng Yan for Large Hadron Collider

Dongsheng Yan led his team to provide more than 5,000 new lead tungstate crystals for the Large Hadron Collider and won the CMS Crystal Award of the European Nuclear Center. He struggled for science and put a "coat" on the missile.

From the "scientific saving of the country" in his youth, to the rejuvenation of the country through the years of science and education, Dongsheng Yan integrated his life into the development of new generations of new materials in New China, and played an important role in the development of the national economy and the construction of major national projects. He is the founder of China's inorganic materials science, as well as an academician of the Chinese Academy of Sciences and Engineering.

Lead tungstate crystal (PbWO4) owns a melting point 1123 ° C, density 8.28g / cm3. It is an inorganic scintillation crystal with excellent comprehensive performance. PbWO4 owns properties of short radiation length (0.87cm), Moliere radius (2.12cm), fast flicker decay time (<50ns), and strong resistance to radiation damage, making it be used in high-energy physics research.

a lead tungstate crystal detector image

Taking country’s needs is the portrayal of Dongsheng Yan's scientific life. In 1918, he was born in Shanghai. In 1946, Mr. Yan went to the United States to study. During his studies at the University of Illinois, he received Ph.D. in ceramics with full A scores. After hearing the news of the founding of New China, he immediately gave up the generous treatment in US, and returned to his motherland resolutely.

At the beginning of returning China, he presided over the formulation of China's first refractory production, inspection, and testing standards, and promoted the development of China's steel industry. In the 1970s, he was urgently ordered to lead more than 50 secret teams to conduct more than 300 types of sample tests in the extremely simple factory. The developed high-temperature ablation composite material successfully solved in New China. He was known as "the person who puts on coat on missile."

Mr. Yan led Shanghai Ceramic Research Institute to accumulate in the field of scintillation crystals. He immediately organized a team to tackle the problem and eventually won a supply contract for 12,000 BGO crystals. In 1985, the National Science Foundation of the US evaluated the BGO products of various countries, and Mr. Yan and his team attained this only chance. Therefore, when the CERN decided to build the Large Hadron Collider to find the Higgs boson, which required tens of thousands of new lead tungstate crystals to make the core components, it was natural to think of Mr. Yan.

At the end of 2003, the conditions were "harsh", as all the crystals had to be produced in four years and more, Mr. Yan did not "bargain" it. At the age of 85, he not only blurted out the test data of a series of PWO crystals but also personally went to the raw material production workshop in Kunshan city, Jiangsu province to check the crystal quality. In March 2008, Shanghai Silicate Institute successfully delivered about 5,000 high-quality large-size PWO crystals without any delaying. In that year, Mr. Yan was 90 years old.

Even at the age of 90, he was still at the forefront and planning his goals and plans for the future. As a project leader, Mr. Yan led his team to provide more than 5,000 new lead tungstate crystals for the Large Hadron Collider (LHC), and won the CMS Crystal Award from the European Organization for Nuclear Research (CERN). Dongsheng Yan has been fighting for our national science career through his life. This kind of patriotic feeling is the role model of younger generation to learn.

 

 

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