作者机构:[1]Department of Engineering Physics, Tsinghua University, Beijing 100084, China, [2]Key Laboratory of Particle and Radiation Imaging, Ministry of Education, Beijing 100084, China
相关基金:Supported by the National Natural Science Foundation of China (No. 10575059), the Program for New Century Excellent Talents in University (No. NCET-05-0060), and the National Natural Science Foundation of China for Young Scholars (No. 10605015)