报告题目：原子陷阱及其应用（Atom Trap, Krypton-81, and Global Groundwater）

报 告 人：卢征天，Physics Division, Argonne National Laboratory，The Department of Physics and Enrico Fermi Institute, The University of Chicago

报告时间：10月29日（周一） 16:00

报告地点：理科楼物理系三层报告厅

报告摘要：The long-lived noble-gas isotope 81Kr is the ideal tracer for old water and ice in the age range of 10^5 – 10^6 years, a range beyond the reach of 14C. 81Kr-dating, a concept pursued over the past four decades by numerous laboratories employing a variety of techniques, is now available for the first time to the earth science community at large. This is made possible by the development of an atom counter based on the Atom Trap Trace Analysis (ATTA) method, in which individual atoms of the desired isotope are selectively captured and detected with a laser-based atom trap. ATTA possesses superior selectivity, and is thus far used to analyze the environmental radioactive isotopes 81Kr, 85Kr, and 39Ar, These three isotopes have extremely low isotopic abundances in the range of 10^-16 to 10^-11, and cover a wide range of ages and applications. In collaboration with earth scientists, we are dating groundwater and mapping its flow in major aquifers around the world. This work is supported by DOE, Office of Nuclear Physics, under contract DE-AC02-06CH11357; and by NSF, Division of Earth Sciences, under award EAR-0651161.

Personal homepage: http://www.phy.anl.gov/mep/staff/Lu_ZT.html