Superallowed 26Alm(β+ + EC)26Mg decay

High-precision branching-ratio measurement for the superallowedβ+emitter26Alm

“…These values are also in agreement with the upper limit for the nonsuperallowed decay of 26 Al m of 7 × 10 −5 reported in Ref. [7], but they provide a lower (1σ ) upper limit by nearly an order of magnitude.…”

“…The 26 Al m Ft value therefore carries, by far, the largest weight in the current world-average superallowed Ft value (Ft) used to determine G V and V ud . An upper limit of <0.007%, established as a byproduct of an 26 Al m Q-value measurement [7], is currently the best experimental upper limit for the total nonsuperallowed β + /EC decay branches of 26 Al m . While this limit is already smaller than the current uncertainties in the half-life (±0.011%) and f value (±0.017%), it is not entirely negligible.…”

Atomic energy loss corrections for (p,n) and (p,γ) nuclear reaction energies

“…(2) Here the subscripts I = P, E refer to the projectile and the ejectile, respectively, vI is the corresponding velocity, KI = MItlI the momentum (MI being the reduced atomic mass), and EI the energy. Also EI -(Ef -E*) i M are Legendre functions of the first and second kinds, respectively, jl is a spherical Bessel function, and (X)f; denotes a radial matrix element of aa operator X between initial and 6nal atomic orbitals of total aagular momentum J~(parity II;) and Jf (parity IIf), while (:::) denotes signer's 3-j symbol.…”

Mass measurements and superallowed decay

“…We compare (p, γ) and (n, γ) reactions in the 24 ≤ A ≤ 28 mass region with very precise (conventional) Penning-trap measurements of stable nuclei, and set limits on possible undetected systematic effects in these reactions. We then derive a very conservative range for the mass excess of radioactive 26 Al based on these reactions alone.…”