Cross Sections for the ReactionsD(d, p)T,D(d, n

Abstract

These cross sections were measured by the process of passing a deuteron beam into a thin gas target contained behind a thin window of evaporated silicon monoxide. The energy loss in the window was measured by a deceleration technique. Charged particles from the reactions were observed at 90° in the laboratory system with proportional counters. Some results are as follows: for the reaction D(d,p)T, by use of the angular distribution reported by Wenzel and Whaling, the total cross section o-is 15.4 mb with a probable error of 3.2 percent at 100-kev incident deuteron energy; cr=0.629 mb±5 percent at 25 kev. For the reaction D(d,n)JIe z , o-=15.2 mb±3.2 percent at 100 kev; <r=0.592 mb±5 percent at 25 kev. The sum of these two cross sections follows a Gamow function below 50 kev. For the reaction T(d,w)He 4 , isotropy in the center-ofmass system being assumed, <r shows a peak value of 4.95 barns=b2.8 percent at 107 kev; at 40 kev, (r = 0.72 barn±3.2 percent; at 19 kev, a-0.045 barn±5 percent; below 19 kev, <r follows a Gamow function. For the reaction He 3 (d,p)He 4 with isotropy assumed, a-=16mb±3 percent at 93 kev; <r=0.124 mb±5 percent at 36 kev; and a follows a Gamow relation below 100 kev.

New reaction rates for improved primordialD/Hcalculation and the cosmic evolution of deuterium

“…[44]. Data sets that significantly deviate from the fits were just not included in the fit (e.g., Tumino et al [17] and Arnold et al [47] for reasons discussed in Appendix C) or have large systematic uncertainties (Krauss et al [41]) that are not included in the error bars of these figures.…”

Estimating reaction rates and uncertainties for primordial nucleosynthesis

“…Other data used for this reaction are from Refs. [39] and [60][61][62]. The lowenergy data of Schröder et al [63], intended to probe electron screening, were omitted here because they did not measure the absolute cross section.…”

Toward a self-consistent and unitary reaction network for big-bang nucleosynthesis

“…It fits the 2665 experimental data points included using 117 free parameters with a χ 2 per degree of freedom of 1.56. The (magenta) squares are the data of Arnold et al [35]; the (olive) diamonds are the data of Jarmie et al [36] renormalized by a factor of 1.017; the (green) triangles are the relative data of Brown et al [37] renormalized by a factor of 1.025. The necessity of these renormalizations of the experimental data is discussed in the text.…”