ORIGIN OF STREAMER MATERIAL IN THE OUTER CORONA

We investigate the nature and origin of the outward-moving density inh omogeneities (''blobs'') detected previously with the Large Angle and Spectrometric Coronagraph on the Solar and Heliospheric Observatory. T he blobs are concentrated around the thin plasma layer that surrounds the heliospheric current sheet and that constitutes the outer streamer belt; they represent only a small, fluctuating component of the total density within the plasma sheet. As noted before in Sheeley et al., b lobs are characterized by low speeds and are continually emitted from the elongated tips of helmet streamers at 3-4 R. from Sun center. We s uggest that both the blobs and the plasma sheet itself represent close d-field material injected into the solar wind as a result of footpoint exchanges between the stretched helmet-streamer loops and neighboring open field lines. The plasma sheet is thus threaded by newly reconnec ted, open magnetic field lines, which lend the white-light streamer be lt its filamentary appearance. Since in situ observations at 1 AU show that the slow wind (with speeds below 500 km s(-1)) spreads over an a ngular extent much greater than the less than or similar to 3 degrees width of the plasma sheet, we deduce that a major component of this wi nd must originate outside the helmet streamers (i.e., from just inside coronal holes).