(See Energy Level Diagrams for 19O)
GENERAL: See 3 [Electromagnetic Transitions in A = 18-19] (in PDF or PS), 19.1 [General Table] (in PDF or PS), 19.2 [Table of Energy Levels] (in PDF or PS) and 19.3 [Radiative decays in 19Ne] (in PDF or PS).
The thermal capture cross section is 0.16 ± 0.01 mb (1981MUZQ). The scattering length b = 5.84 ± 0.07 fm, σfree = 3.86 ± 0.10 b (1979KO26). The total cross section has been measured for En = 0.14 to 2.47 MeV [see (1978AJ03)] and at En = 5 to 7.5 MeV [G. Auchampaugh, quoted in (1986KO10)]. A multi-level R-matrix analysis of these and additional σ(θ) data leads to the states shown in 19.6 (in PDF or PS) and to some additional structures. The five 7/2- states [19O*(6.27, 9.64, 9.84, 10.21, 10.66)] (see, however, footnote (a) to 19.6 (in PDF or PS)) contain about 20 - 30% of the allowed f7/2 single-particle strength. See also the compilation of neutron cross sections in (1988MCZT). Isobaric analog assignments are presented (1986KO10). See also (1982RA1A) and see the astrophysical discussion in (1988AP1A, 1988MA1U).
The total cross sections for the α0 and α1 groups have been measured for En = 7.5 to 8.6 MeV: resonance structure is reported at En = 7.70 ± 0.05 and 8.05 ± 0.05 MeV with Γlab = 0.25 and 0.35 MeV, respectively [19O*(11.25, 11.58)]: see (1978AJ03).
Angular distributions have been measured at Ed = 0.8 to 15 MeV: see (1978AJ03, 1983AJ01). The ln values and spectroscopic factors derived from these measurements are displayed in 19.5 (in PDF or PS). Branching ratios are shown in 19.3 (in PDF or PS). 19O*(0.096) has g = -0.48 ± 0.06; its configuration appears to be mainly d35/2, and B(M1) = 0.040 ± 0.015 μ2N. The ΔE value for the 1.47 → 0.096 transition is 1375.3 ± 0.5 keV. Assuming Ef = 96.0 ± 0.5 keV ( 19.2 (in PDF or PS)), Ei = 1471.4 ± 0.7 keV. Angular correlations are consistent with Jπ = 5/2+ for the ground state and unambiguously fix Jπ = 3/2+ and 1/2+, respectively, for 19O*(0.096, 1.47): see (1978AJ03) for references. See also (1986SE1B).
Many measurements of the half-life have been reported (see 19N) and a value of 0.304 ± 0.016 s has been adopted. A neutron emission probability of 33+34-11% (1988MU08) and 62.4 ± 2.6% (1991RE02) has been measured. Shell model predictions for the 19N(β-)19O decay are discussed in (1988WA17), and a β- delayed γ decay scheme for 19O based on measurements of (1986DU07) (Eγ = 96.0 ± 1.0, 709.2 ± 0.8, and 3137.8 ± 1.0 keV with relative intensities of 100 ± 10, 63 ± 21, and 76 ± 21) is proposed. Arguments for Jπ = (3/2+) and (1/2, 3/2-) for the 3067 and 3232 keV levels are given. Evidence on the formation and decay of the 3945 keV complex of levels is reviewed. These calculations predict a 19N half life of 0.54 s and a neutron emission probability Pn = 0.87. They also predict Jπ = 1/2- for the 19N ground state and branching ratios for decay to 19O levels.
Transitions to 19O*(0[u], 4.9, 6.3) have been observed in the radiative capture of stopped negative pions (1983MA16).
See (1986HEZW; En = 200 MeV).
Differential cross sections for the 19O ground state and Ex = 0.1 MeV state were measured at Et = 33 MeV (1991PI09). A DWBA analysis was carried out.