Author/Authors :
D.W. Bardayan، نويسنده , , J.C. Blackmon، نويسنده , , J. G?mez del Campo، نويسنده , , R.L. Kozub، نويسنده , , J.F. Liang، نويسنده , , Z. Ma، نويسنده , , L. Sahin، نويسنده , , D. Shapira، نويسنده , , M.S. Smith، نويسنده ,
Abstract :
The rates of the 18F(p, α)15O and 18F(p, γ)19Ne reactions in astrophysical environments depend on the properties of 19Ne levels above the 18F +p threshold. There are at least 8 levels in the mirror nucleus 19F for which analogs have not been observed in 19Ne in the excitation energy range Ex=6.4–7.6 MeV. These levels may significantly enhance the 18F +p reaction rates, and thus we have made a search for these levels by measuring the 1H(18F,p)18F excitation function over the energy range Ec.m.=0.3-1.3 MeV. We have identified and measured the properties of a newly observed level at Ex=7.420±0.014 MeV, which is most likely the mirror to the View the MathML source19F level at 7.56 MeV. We have additionally found a significant discrepancy with a recent compilation for the properties of a 19Ne state at Ex=7.5 MeV and set upper limits on the proton widths of missing levels.
