A study of the proton resonant property in 22 Mg by elastic scattering of 21 Na + p and its astrophysical implication in the 18 Ne(α, p) 21 Na reaction rate

. Proton resonances in 22 Mg have been investigated by the resonant elastic scattering of 21 Na + p . The 21 Na beam with a mean energy of 4.00 MeV/nucleon was separated by the CNS radioactive-ion-beam separator (CRIB) and bombarded a thick ( CH 2 n target. The energy spectra of recoiled protons were measured at scattering angles of θ c.m. ≈ 172 ° , 146 ° , respectively. Several excited states observed before have been confirmed including two states (at 6.616, 6.796 MeV) observed at TRIUMF. A new state at 7.06 MeV has been observed, and another new one at 7.28 MeV is tentatively identified due to its low statistics. The proton resonant parameters were deduced from an R -matrix analysis of the differential cross-section data with a SAMMY-M6-BETA code. The astrophysical implication for the 18 Ne (α, p ) 21 Na reaction has been briefly discussed.