Energy Levels of Light Nuclei A = 14 - Triangle Universities Nuclear ...

polynominals and fitted the coefficients at resonances corresponding to 14 N*(13.16, 13.24, 13.67,
13.76) obtaining J π =1 + ,2 − ,2or3 + , and 1, respectively, for these states. However, an R-matrix
analysis by (83CS03) suggests J π =2 − ,3 + ,1 + for 14 N*(13.69, 13.74, 13.77). (75WI04) finds that
a surprising proportion of states have a higher cross section for neutron than for proton emission:
the fluctuations of σ n /σ p at low E α suggest sizable isospin impurities in the 14 N states.
4. (a) 10 B(α, d) 12 C Q m =1.3401 E b =11.6125
(b) 10 B(α, t) 11 C Q m = −11.1244
Excitation curves have been measured at E α up to 27 MeV [see (70AJ04, 76AJ04, 81AJ01)].
The low energy resonances are exhibited in Table 14.12. At the higher energies the yield curves
are fairly smooth although broad resonances in the d 1 and d 0 yields corresponding to 14 N*(23.25),
respectively have been reported as has a sharp rise in the 15.1 MeV γ yield ≈ 1MeVabovethe
12 C* (15.1) + p + n threshold, a channel which is not isospin forbidden: see (81AJ01). For cross
sections at E α =29.5 MeV (reaction (a)) and 25.0 and 30.1 MeV (reaction (b)) see (83VA28). See
also 12 Cin(90AJ01) and(89VA07).
5. 10 B(α, α) 10 B E b =11.6125
The yield of α-particles [and of 0.7 MeV γ-rays for E α =2.1 to 3 MeV] has been measured for
E α to 50.6 MeV: see (81AJ01). Observed resonances are displayed in Table 14.12. In addition to
two strong resonances in the α 0 yields at E α =2.21 and 4.26 MeV ( 14 N*(13.19, 14.66)), two other
states ( 14 N*(13.72, 14.25)) are required to fit the data: an R-matrix calculation leads to J π =3 + ,
1 + [see, however, (75WI04)], 3 + and 2 − for 14 N*(13.19, 13.72, 14.25, 14.66): see (81AJ01).
6. 10 B( 6 Li, d) 14 N Q m =10.1374
States with E x > 10 MeV studied in this reaction at E( 6 Li) = 34 MeV are displayed in Table
14.13 (84CL08). In addition most of the lower-lying T = 0 states have been populated: see (70AJ04,
81AJ01).
7. 10 B( 7 Li, t) 14 N Q m =9.1446
At E( 7 Li) = 24 MeV angular distributions of the tritons to 14 N*(3.95, 5.83, 6.45, 8.96, 9.13,
10.06, 10.81, 12.79 + 12.81, 13.03, 15.26) have been studied. 14 N*(4.91, 5.11, 5.69, 6.20, 7.03, 7.97,
8.49, 8.98, 9.39, 11.05, 11.51, 12.42) are also populated: see (81AJ01).
8. 10 B( 9 Be, αn) 14 N Q m =10.0390
For cross sections see (86CU02).
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