Examination of the role of theO14(α,p)F17reac

Abstract

The 14 O(α,p) 17 F reaction is one of the key reactions involved in the breakout from the hot-CNO cycle to the rp-process in type-I x-ray bursts (XRBs). The resonant properties in the compound nucleus 18 Ne have been investigated through resonant elastic scattering of 17 F+p. The radioactive 17 F beam was separated by the Center for Nuclear Study radioactive ion beam separator (CRIB) and bombarded a thick H 2 gas target at 3.6 MeV/nucleon. The recoiling light particles were measured by three E-E silicon telescopes at laboratory angles of θ lab ≈3 • , 10 • , and 18 • . Five resonances at E x = 6.15, 6.28, 6.35, 6.85, and 7.05 MeV were observed in the excitation functions, and their spin-parities have been determined based on an R-matrix analysis. In particular, J π = 1 − was firmly assigned to the 6.15-MeV state which dominates the thermonuclear 14 O(α,p) 17 F rate below 2 GK. As well, a possible new excited state in 18 Ne was observed at E x = 6.85 ± 0.11 MeV with tentative J = 0 assignment. This state could be the analog state of the 6.880 MeV (0 − ) level in the mirror nucleus 18 O, or a bandhead state (0 + ) of the six-particle four-hole (6p-4h) band. A new thermonuclear 14 O(α,p) 17 F rate has been determined, and the astrophysical impact of multiple recent rates has been examined using an XRB model. Contrary to previous expectations, we find only a modest impact on predicted nuclear energy generation rates from using reaction rates differing by up to several orders of magnitude.

Advancement of Photospheric Radius Expansion and Clocked Type-I X-Ray Burst Models with the New $^{22}$Mg$(α,p)^{25}$Al Reaction Rate Determined at Gamow Energy

“…[57], 14 O(α,p) [58], 23 Al(p,γ) [59], and 18 Ne(α,p) [60], to highlight the relevance of the 22 Mg(α,p) reaction among them. These reactions are listed in Table 2 and Fig.…”

“…The nuclear structure information provided from the shell-model calculations covers the Gamow window corresponding to the XRB temperature range. We then take these 59 Cu(p,γ) and 61 Ga(p,γ) rates prior to their publication [57], also the Present 22 Mg(α,p), 14 O(α,p) [58], 23 Al(p,γ) [59], 18 Ne(α,p) [60], 55 Ni(p,γ) [62], 56 Ni(p,γ) [63], 57 Cu(p,γ) [64], 64 Ge(p,γ) [61], and 65 As(p,γ) [61] reaction rates to study the combined influence of these reactions on the GS 1826−24 burst lightcurve profile [4] (see Fig. 7).…”

Research program of nuclear astrophysics based on the HIAF

“…Ne, 19 Ne(p, γ) 20 Na, 56 Ni(p, γ) 58 Cu, 25 Al(p, γ) 26 Si, 14 21 Na(图11)等反应的研究 [47][48][49] , 为将来在HIAF开展 更丰质子核区的相关反应奠定了基础. [50] , 包括近质子滴线 短寿命核素 63 Ge, 65 As, 67 Se和 71 Kr的质量 [51] 和缺中子 短寿命原子核(尤其是 存在的Ca-Sc循环 [52] .…”

First measurement of S30+α resonant elastic scattering for the S30Kahl1, Yamaguchi2, Kubono3 et al. 2018Phys. Rev. CSelf Cite140100View full textAdd to dashboardCite

“…The (α, p) reactions occurring on lower mass nuclei such as 14 O and 18 Ne have been measured directly [24][25][26][27][28], and the properties of resonances in the compound nuclei 18 Ne and 22 Mg have been the subject of a number of indirect studies (see, e.g., Refs. [29,30] and references therein). In spite of these extensive works, those cross sections still remain quite uncertain.…”