|
![]() |
![]() |
![]()
14B (1991AJ01)(See Energy Level Diagrams for 14B) GENERAL: See also (1986AJ01) and Table 14.1 [Table of Energy Levels] (in PDF or PS) here. Complex reactions involving 14B: (1986BI1A, 1987SA25, 1988AS1C, 1988RU01, 1989AS1B, 1989YO02). Pion capture and reactions: (1983AS01, 1984AS05). Hypernuclei: (1986ME1F, 1988MA1G, 1989BA92). Other topics: (1984VA06, 1986AN07, 1989PO1K, 1990RE04). Ground state of 14B: (1987VA26, 1990LO10). Interaction cross sections at 790 MeV/A for 14B ions on Be, C and Al are reported by (1988TA10) [see also for interaction and r.m.s. radii for the nucleon distribution in 14B]. See also (1989SA10).
14B has a half-life of 16.1 ± 1.2 ms (1974AL11), 12.8 ± 0.8 ms (1986CU01): the weighted mean is 13.8 ± 1.0 ms and we adopt it. The nature of the decay [see Table 14.2 (in PDF or PS)] fixes Jπ of 14B to be 2- (1974AL11). See also (1989PO1K; theor.).
A single strong transition is observed in this pion capture cross section to a state in 14B at Ex = 2.15 ± 0.17 MeV, Γ = 1.0 ± 0.5 MeV, with Jπ = 2-. The relative branching ratio of the ground state [2-] to this second 2- state is < 0.1. The data are also suggestive of the population of 2- and 1- states in the Ex = 5 - 7 MeV region (1983BA36).
Ground-state angular distributions have been reported at En = 65 MeV (1986DR1F, 1988DRZZ; prelim.).
14B states with 0 < Ex < 3 MeV have been populated in this reaction at E(7Li) = 52 MeV: see Table 14.1 (in PDF or PS). Similarities in the relative intensities of 14B*(0, 0.74, 1.38, 1.82, 2.08) and of 12B*(1.67, 2.62, 3.39, 4.30, 4.52) [populated in 12C(7Li, 7Be)12B], and the similarity in the ΔEx of these 12B states with the Ex of the 14B states suggest that they have the same Jπ (1973BA34).
The work quoted in (1986AJ01) has
not been published.
|
![]() |