SCIENCE CHINA Physics, Mechanics & Astronomy print-crossmark January 2020 Vol. 63 No. 1: 212021 https://doi.org/10.1007/s11433-019-9411-2 c ⃝ Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019 phys.scichina.com link.springer.com . Letter to the Editor . New determination of astrophysical 14 C( n , γ) 15 C reaction rate from the spectroscopic factor of 15 C TianLi Ma 1 , Bing Guo 1* , DanYang Pang 2,3* , ZhiHong Li 1 , Yi Su 1 , XinYue Li 1 , YangPing Shen 1 , YouBao Wang 1 , YunJu Li 1 , Jun Su 4,1 , ShengQuan Yan 1 , Sheng Zeng 1 , Gang Lian 1 , Ding Nan 1 , and WeiPing Liu 1 1 Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, China; 2 School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China; 3 Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beijing 100191, China; 4 College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875, China Received March 26, 2019; accepted April 10, 2019; published online April 29, 2019 Citation: T. L. Ma, B. Guo, D. Y. Pang, Z. H. Li, Y. Su, X. Y. Li, Y. P. Shen, Y. B. Wang, Y. J. Li, J. Su, S. Q. Yan, S. Zeng, G. Lian, D. Nan, and W. P. Liu, New determination of astrophysical 14 C(n, γ) 15 C reaction rate from the spectroscopic factor of 15 C, Sci. China-Phys. Mech. Astron. 63, 212021 (2020), https://doi.org/10.1007/s11433-019-9411-2 The 14 C(n, γ) 15 C reaction plays an important role in various astrophysical scenarios: (1) it is the slowest in the neutron induced CNO cycle which occurs in asymptotic giant branch (AGB) stars, and therefore controls this cycle [1]; (2) it is one of the key reactions for predicting the primordial abundances of the heavy elements in the framework of inhomogeneous big-bang nucleosynthesis (IBBN) [2]; (3) it is also important for the synthesis of heavier isotopes in neutrino driven wind scenarios for the r-process in core-collapse supernova (i.e., Type-II supernova) explosions [3-5]. Due to its importance, the 14 C(n, γ) 15 C reaction has drawn much attention. To date its cross sections have been investi- gated through various techniques involving theoretical calcu- lations [6-8], direct measurements [9-11] and indirect mea- surements including Coulomb dissociation method [12-17] and asymptotic normalization coefficient/spectroscopic fac- tor (ANC/SF) method [18-21]. However, there has been con- troversy in these results on the 14 C(n, γ) 15 C cross sections. The first direct measurement provided a value of (1.18 ± 0.29) μb for the 14 C(n, γ) 15 C cross section at the energy kT = 23.3 keV in 1992 [9]. This value is five times smaller than the one (5.1 μb) derived by Wiescher et al. [18] using the *Corresponding authors (Bing Guo, email: guobing@ciae.ac.cn; DanYang Pang, email: dypang@buaa.edu.cn) SF from the 14 C(d, p) 15 C reaction [22]. Note that all the val- ues of σ n,γ (23.3 keV) mentioned in this letter are not the Maxwellian average cross section (MACS) at the tempera- ture kT = 23.3 keV but the cross section at the energy kT = 23.3 keV. After these two pioneering studies, the folding model cal- culations in 1999 [6] and microscopic cluster model calcula- tions in 2000 [7] confirmed the large value of σ n,γ (23.3 keV) in ref. [18]. The subsequent calculations using halo effective field theory provided three different values by reproducing the direct capture data from ref. [11] and the Coulomb dis- sociation data from ref. [15]. Reifarth et al. performed two new direct measurements and suggested σ n,γ (23.3 keV) to be (1.85 ± 0.15) μb in 2005 [10] and (4.86 ± 0.34) μb in 2008 [11] which is about 3 times larger than the one from the first direct measurement. The σ n,γ (23.3 keV) of 4.86(34) μb was determined from the MACS of 7.1(5) μb reported in ref. [11] using the relation σ MAC ≈ 1.46 σ(kT ) derived from the struc- ture models [16]. Meanwhile, several Coulomb dissociation experiments using a 15 C beam on high-Z target [12, 13, 15] and reanalysis of these data [14, 16, 17] yielded approximately coincident values of σ n,γ (23.3keV) with the exception of ref. [12]. As for the ANC/SF method, in addition to the earlier study of ref. [18], the 14 C(n, γ) 15 C cross section has been in-