Semidirect

"1984, I. Berqvist, Chapter II: Fast Neutron Radiative Capture, B. J. Allen, I. Bergqvist, R. E. Chrien, D. Gardner, W. P. Poenitz (contributing authors), Neutron Radiative Capture: Neutron Physics and Nuclear Data in Science and Technology, page 33, In the next step, the giant dipole state may deexcite by the emission of γ-rays. This reaction is called "semidirect". It turns out that direct and semidirect reactions play a dominating role at neutron energies higher than about 5 MeV."

"It follows from 2° that σ induces the action homomorphism θ = σπ₁, which we call semidirect. We say that σ is a homomorphic transformation of (A, U). If θ is the semidirect action homomorphism, then it follows from 1° that the θ-module is the semidirect sum ^𝔇 of (A^× U^×) and (B, V)."