Constraining the External Capture to the O16 Ground State and the E2 Author(s) - Y. P. Shen, Bing Guo, R. J. deBoer, Zhihong Li, Y. J. Li, Xindi Tang, D. Y. Pang, S. Adhikari, Chinmay Basu, J. Su, S. Q. Yan, Q. W. Fan, J. C. Liu, Chen Chen, Z. Y. Han, X. Y. Li, G. Lian, A. L. Tadross, Wei Nan, Weike Nan, Y. B. Wang, Sheng Zeng, Hengliang Zhang, W. P. Liu