The identification of the long-period X-ray pulsar 1WGA J1958.2+3232 with a Be-star/X-ray binary

We present the results of optical observations performed between May and Se ptember 1998 of the stars within the position error circle of the recently discovered similar to 12 min pulsating X-ray source 1WGA J1958.2+3232. Base d on photometry and slitless spectroscopy, we selected a likely optical cou nterpart, which was subsequently determined to be a m(V)=15.7 BOVe star, th e spectral properties of which are in good agreement with the X-ray results . The proposed optical counterpart shows several H, He and Fe emission-line s, while the interstellar absorption spectral features place the star at a distance of similar to 800 pc. The inferred X-ray luminosity for this dista nce is similar or equal to 10(33) erg s(-1) in the 2-10 keV band. We conclu de that 1WGA J1958.2+3232 is a likely new long-period low-luminosity accret ing neutron star in a Be-star/X-ray binary system.