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14O (59AJ76)(Not illustrated) GENERAL: See also Table 14.13 [Table of Energy Levels] (in PDF or PS). Mass of 14O: The mass excess of 14O is 12.149 ± 0.007 MeV, based on the threshold energy of the 12C(3He, n)14O reaction (BR57) and on the Wapstra masses (WA55C) for 12C, 3He and n. The binding energies of a proton, alpha particle, 3He-particle and deuteron in 14O are, respectively, 4.621, 10.25, 17.563 and 22.58 MeV. In terms of the Mattauch masses (MA56M), the mass excess obtained by (BR57) is 12.146 ± 0.0065 MeV.
The decay proceeds primarily (99.4 ± 0.1 %) (SH55D) to the J = 0+; T = 1 first excited state of 14N: Eβ+(max) = 1.835 ± 0.008 (GE54); 1.830 ± 0.030 MeV (PE54A); Eγ = 2.30 ± 0.03 MeV (SH53A). Using Q for 12C(3He, n)14O = 1.1585, 14N* = 2.313 ± 0.005, and mass excess of (MA56M), (BR57) calculate Eβ+(max) = 1.8097 ± 0.0078. The positron spectrum has an allowed shape (GE54). The half-life is 72.1 ± 0.4 sec (GE54), ft = 3088 ± 56 sec (BR57); see also (GE58). The direct ground state transition occurs in (0.60 ± 0.10)% of the cases: ft = (2.0 ± 0.3) x 107 sec. The corresponding matrix element is about 50 times larger than that for 14C(β-)14N. Explicit wave functions for 14O, 14N, and 14C are derived (SH55D: see also (JA54A, EL56B, VI57). A slight deviation from linearity in the Kurie plot is predicted by (VI57, GO58C). The polarization of the positrons has been studied by (GE58D). See also (SH57B, BE58E, GE58B, MA58C, SU58; theor.).
See (NO57A).
This reaction has been studied from threshold to E(3He) = 2.7 MeV (BR57: see 15O). (BU56A) report a tentative threshold value of E(3He) = 1.435 MeV; Q = -1.148 ± 0.004 (WA58C).
At Ep = 17.3 MeV, neutron groups are observed to the ground state and to broad or unresolved states of 14O at ~ 6.2, 7.5 and 9.3 MeV (AJ54). See also (BO58).
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