1. Deep underground laboratory measurement of $^{13}$C($\alpha$,$n$)$^{16}$O in the Gamow windows of the $s$- and $i$-processes
- Author
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Gao, B., Jiao, T. Y., Li, Y. T., Chen, H., Lin, W. P., An, Z., Ru, L. H., Zhang, Z. C., Tang, X. D., Wang, X. Y., Zhang, N. T., Fang, X., Xie, D. H., Fan, Y. H., Ma, L., Zhang, X., Bai, F., Wang, P., Fan, Y. X., Liu, G., Huang, H. X., Wu, Q., Zhu, Y. B., Chai, J. L., Li, J. Q., Sun, L. T., Wang, S., Cai, J. W., Li, Y. Z., Su, J., Zhang, H., Li, Z. H., Li, Y. J., Li, E. T., Chen, C., Shen, Y. P., Lian, G., Guo, B., Li, X. Y., Zhang, L. Y., He, J. J., Sheng, Y. D., Chen, Y. J., Wang, L. H., Zhang, L., Cao, F. Q., Nan, W., Nan, W. K., Li, G. X., Song, N., Cui, B. Q., Chen, L. H., Ma, R. G., Yan, S. Q., Liao, J. H., Wang, Y. B., Zeng, S., Nan, D., Fan, Q. W., Qi, N. C., Sun, W. L., Guo, X. Y., Zhang, P., Chen, Y. H., Zhou, Y., Zhou, J. F., He, J. R., Shang, C. S., Li, M. C., Kubono, S., Liu, W. P., deBoer, R. J., Wiescher, M., and Pignatari, M.
- Subjects
Nuclear Experiment - Abstract
The $^{13}$C($\alpha$,$n$)$^{16}$O reaction is the main neutron source for the slow-neutron-capture (s-) process in Asymptotic Giant Branch stars and for the intermediate (i-) process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray induced background. We performed the first consistent direct measurement in the range of $E_{\rm c.m.}=$0.24 MeV to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory (CJPL) and Sichuan University. Our measurement covers almost the entire i-process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60\% down to 15\%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing data sets, and provides a more reliable reaction rate for the studies of the s- and i-processes along with the first direct determination of the alpha strength for the near-threshold state.
- Published
- 2022
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