On March 5th, 2016, Nobel Laureate physicist Samuel C. C. Ting (Chinese name: DING Zhaozhong) visited USTC and gave an interesting talk about "The Latest Progress of the AMS on the ISS." The exciting results of the experiment as well as the way how a great physicist try to understand the universe deeply touched the audience.
Mr. DING's talk attracted hundreds of admirers, many of which are students and researchers. The prepared auditorium was not large enough. In order to hold the entire audience, one nearby auditorium was opened with real-time video broadcasts. It was not however, Mr. DING's first visit. "Some professors sitting here have seen Mr. DING when they were young students at USTC. Some were Mr. DING's graduate students in the US. Our Physics Department, in particular areas like high energy physics and particle physics, has seen great improvements with the help of Mr. DING.", said ZHAO Zhengguo, a CAS Academician and director of the Center for Particle Science and Technology (CPST) of USTC.
The Alpha Magnetic Spectrometer (AMS) is a particle physics experiment module that is assembled on earth, launched into orbit, and mounted onto the International Space Station (ISS). It is designed to measure antimatter in cosmic rays and search for evidence of dark matter. Mr. DING talked about the scientific objectives and the assembling processes, "It was the first time we sent such delicate physical experiment into space. Everything was new. We had to build everything from scratch." None of the achievements were easy or done by one single group. "There are data centers around the globe. Several crucial instruments were built with the cooperation of Chinese institutes." He applied himself to the challenges with joyful energy and passionate enthusiasm. When Mr. DING talked about the day when STS-134 would take AMS to the ISS on May 16, 2011, he paused for a while and told us, "I asked all my colleagues to leave. I recalled step by step what we had done with the AMS and made sure there's nothing left uncertain. After several hours, I persuaded myself that everything was ready and left the office. I still remember that moment. I was soaked in sweat."
The AMS experiment took advantage of the unique environment of outer space to search for dark matter by measuring cosmic rays. Mr. DING introduced several exciting results with AMS. Some came well along with theoretical predictions, some did not. In 2013, one of the results about the discovery of dark matter with AMS was broadly reported over the media. However, Mr. DING exercised prudence as a top experimental physicist. "All the current dark matter results are in line with the predicted properties. However, this does not suggest that we have found the dark matter for certain. We have yet one more property to check." There was a storm of applause in the audience. He also pointed out that there are more information that we can generate from the AMS data besides dark matter, and much work is left be done by scientists of younger generations.
Mr. DING's talk is full of rational thinking but never devoid of intelligent humor. He showed us how a scientist should struggle to cope with the difficulties and achieve the ultimate goal, which is to improve our understanding of the universe. He used Mandarin all through the talk and took questions afterwards.
For more informations:
DING Zhaozhong : https://zh.wikipedia.org/wiki/%E4%B8%81%E8%82%87%E4%B8%AD
AMS: Alpha Magnetic Spectrometer, https://en.wikipedia.org/wiki/Alpha_Magnetic_Spectrometer
ISS: International Space Station, https://en.wikipedia.org/wiki/International_Space_Station
(USTC News Center, HUANG Xingxing, SUN Yong)