R-matrix analyses of the 12C + α elastic-scattering phase shifts deduced from a recent high-precision measurement of the differential cross sections are performed. The ℓ = 0 phase shifts constrain the R-matrix radius a around 5.85 fm, while the t ℓ= 2 phase shifts lead to a strong constrain neither on a nor on the asymptotic normalization constant C of the 2+ subthreshold state (except for a loose upper limit). This contradicts previous R-matrix analyses of the 12C + α elastic scattering and explains the incompatibility between values of C obtained in these analyses. © 2004 Elsevier B.V. All rights reserved.
Spanrenberg, J. M. (2004). Deducing the asymptotic normalization constant of the 2+ subthreshold state in 16O from 12C + α elastic scattering. Nuclear Physics A, 738(1-4 SUPPL.), 416–420. https://doi.org/10.1016/j.nuclphysa.2004.04.077