Influence of one-particle states in the continuum on the low-lying, negative-parity states in O

Balashov's resonance approximation is used to calculate the level shifts and widths of the low-lying, negative-parity states in ¹⁷O, assuming these states to be 2p-1h structure. It turns out that the coupling to one-particle continuum states is very important not only for the widths but also for the positions of most of the levels. The results prove to be very sensitive to the positions of the single-particle resonances in the (2p, 1f) shell.