New approach to spin assignments of intermediate structures inC12(

Abstract

Magnetic substate populations for the 2+ state at 4.44 MeV in C were measured in resonant C+ 0 inelastic scattering by the p-ray recoil method. The m-substate population has been determined in the coordinate frame where a quantization axis is taken along the center of mass scattering angle of a reaction product. This coordinate frame gives an advantage that a resonance spin J can be obtained directly from m-substate angular distributions compared with the beam-axis frame. In addition a decay L value is sensitive to the relative intensity between each m-substate cross section. Our data suggest a spin assignment of J = 16+ or 17 for the structures at E, = 29.8 MeV and 31.8 MeV. Both structures are determined to decay dominantly through the aligned con6guration of L = J -2. PACS number(s): 25.70.Ef, 24.70.+s, 21.10.Hw Recent measurements of the magnetic substate populations in resonant inelastic scattering have provided us with important information for clarifying the reaction mechanism on the observed resonance behavior [1 -7].