The first excited states of 9Be and 9B

It is found here that the 1/2(+) first excited state of Be-9 is a virtual state with the energy of -23.5 KeV. The line shape for the excitation of the state is approximated with a simple analytic form based on the effective range expansion. The partner in B-9 of this state is found to be a resonance with a maximum in the peak at about 1.1 MeV, FWHM, of 1.5 MeV, and complex energy of 0.6 - i0.75 MeV. The line shape for its excitation is calculated in terms of the p-Be-8 phase shift. The phase shifts are obtained from N-Be-8 effective potentials deduced from the data on the photodisintegration of Be-9. A possibility for direct extraction of the energy of the resonant state from experimental data is also discussed; and an expression for a residue at a virtual state pole in terms of a quadrature taken over the virtual state eigenfunction is given.