N13(d,n)

Z. H. Li

¹

,

S. Q. Yan

²

,

Gang Liu

³

et al.

Abstract

Abstract13 N(p, γ) 14 O is one of the key reactions in the hot CNO cycle which occurs at stellar temperatures around T 9 ≥ 0.1. Up to now, some uncertainties still exist for the direct capture component in this reaction, thus an independent measurement is of importance. In present work, the angular distribution of the 13 N(d, n) 14 O reaction at E c.m. = 8.9 MeV has been measured in inverse kinematics, for the first time. Based on the distorted wave Born approximation (DWBA) analysis, the nuclear asymptotic normalization coefficient (ANC), C 14 O 1,1/2 , for the ground state of 14 O → 13 N + p is derived to be 5.42 ± 0.48 fm −1/2 . The 13 N(p, γ) 14 O reaction is analyzed with the R-matrix approach, its astrophysical S-factors and reaction rates at energies of astrophysical relevance are then determined with the ANC. The implications of the present reaction rates on the evolution of novae are then discussed with the reaction network calculations.

First measurement of the 2H(6He,7Li)n angular distribution and proton spectroscopic factor in 7Li

“…Lapikás et al [14] deduced the proton spectroscopic factor of 7 Li to be 0.42 ± 0.04 via the measurement of the 7 Li(e, e p) reaction. This value is 32% a e-mail: zhli@ciae.ac.cn smaller than that from the 7 Li(n, d) 6 He reaction. Thus, further measurement of the 7 Li spectroscopic factor is highly desired.…”

“…Single-nucleon transfer reactions such as (d, p) and (d, n) have been used extensively to extract the spectroscopic information of the single-nucleon orbits in nuclei located at or near the stability line [1][2][3]. The spectroscopic study of exotic nuclei becomes feasible since the production of radioactive ion beams [4][5][6]. These measurements allow the extraction of the spectroscopic factors by normalizing the calculational differential cross-sections with the distorted-wave Born approximation (DWBA) to the experimental ones at forward angles.…”

“…The ( 7 Li, 6 He) reaction is a valuable spectroscopic tool in the study of nuclear reactions because the shape of its angular distribution can be well reproduced by DWBA calculations [7]. In the calculations of ( 7 Li,6 He) reactions [7][8][9][10][11], the spectroscopic factor of the 7 Li ground state was taken to be 0.59 [12]. Brady et al [13] extracted the spectroscopic factor of the 7 Li ground state to be S(p 3/2 ) = 0.62 from the 7 Li(n, d) 6 He reaction with 56.3 MeV neutrons.…”

“…In the present work, the 2 H( 6 He, 7 Li)n angular distribution was measured by using a secondary 6 He beam of 36.4 MeV and analyzed with DWBA. The proton spectroscopic factor in 7 Li was then extracted and compared with the existing ones.…”

“…In the calculations of ( 7 Li,6 He) reactions [7][8][9][10][11], the spectroscopic factor of the 7 Li ground state was taken to be 0.59 [12]. Brady et al [13] extracted the spectroscopic factor of the 7 Li ground state to be S(p 3/2 ) = 0.62 from the 7 Li(n, d) 6 He reaction with 56.3 MeV neutrons. Lapikás et al [14] deduced the proton spectroscopic factor of 7 Li to be 0.42 ± 0.04 via the measurement of the 7 Li(e, e p) reaction.…”