The photodisintegration of 15N through excited states of 14N, 14C and 12C

The photodisintegration of 15N through excited states of the residual nuclei has been studied by measuring the yields of de-excitation γ rays in a Ge(Li) detector. Cross sections for all observed transitions were deduced from measurements with bremsstrahlung end-point energies ranging from 15 to 35 MeV and account for an integrated cross section of 44 MeV mb. Bound states in 14N and 14C with a dominant (1Psub(1/2))-1 or (1Psub(3/2))-1 configuration are found to be strongly populated. The nature of the states in the 15N giant resonance is discussed. The 15N(γ,t)12C* (4.44 MeV) reaction was also observed and its integrated cross section is approximately 5% of the expected value of the E1 sum rule. Integrated cross sections for 160(γ,sub(p)sup(n)γ) transitions measured at the same time are given. Resonance fluorescence is observed from the 15N 10.07 MeV level, for which GAMMAsub(γ)0 = 4.2 +- 1.5 eV is deduced. (author)