Interstellar medium surrounding the WO star in the galaxy IC 1613: New optical and radio observations

Observations of the nebula S3 associated with the WO star in the galaxy IC 1613 and of an extended region surrounding S3 are reported. The star and br ight core of the nebula were observed with a multipupil fiber spectrograph mounted on the 6-m telescope of the Special Astrophysical Observatory of th e Russian Academy of Sciences. Images in the principle spectral lines and i ntegrated spectra of the star and three compact clumps were obtained, and t he radial-velocity field constructed. An extended region of the galaxy was observed with the Very Large Array at 21 cm. A giant ring or H I shell encl osing a large fraction of the stellar population in IC 1613 was discovered. The WO star and associated bipolar nebula, which we discovered earlier, li e at the inner edge of the H I ring. A local H I deficiency and two arclike H I ridges were also detected for the first time and probably represent th e neutral component of the bipolar shell surrounding the WO star. The two a rclike ridges may also have been produced by the collective stellar wind la nd supernova explosions?) in OB association No. 9 from the list of Hedge. A scenario for the Formation of the extended bipolar feature is discussed, b ased on the new data. (C) 2001 MAIK "Nauka/Interperiodica".