¹⁰⁰ Mo(p, d) ⁹⁹ Mo reaction at 21 MeV and direct reaction analysis of the low-lying continuum spectrum

The ¹⁰⁰ Mo(p, d) ⁹⁹ Mo reaction has been studied with 21 MeV polarized protons. Momentum spectra of the emitted deuterons corresponding to the excitation energy region up to 5.75 MeV in ⁹⁹ Mo have been measured. Theoretical analysis based on the standard distorted-wave Born approximation (DWBA) provides the lj-angular momentum transfers and spectroscopic factors of neutron hole states for 27 levels from the ground state up to E _X = 2.921 MeV. The polarization data gave a more affirmative information in assigning the spins and parities. Spectrum regions from discrete levels to continuum were treated with a global analysis using the direct reaction model and continuous strength functions. The double differential cross section-energy spectra were reproduced fairly well using the DWBA-based cross sections and the asymmetrical Lorentzian form strength response function having energy-dependent spreading widths.