Acceleration profile of the slow solar wind as inferred from gradual mass ejections observed by LASCO

The slow solar wind (< 400 km s(-1)) appears to initiate from the regions i n the corona where magnetic fields are closed, or from the interface betwee n streamers and other coronal regions. The nature of the acceleration of sl ow solar wind is not yet well known. LASCO observations of gradually evolvi ng mass ejections offer us a goad opportunity to study the speed and accele ration profiles of the slow solar wind from a distance of 1.1 up to 30 R.. We present speed and acceleration profiles of slow solar wind, derived on t he basis of measurements of mass flows in several cases of gradual mass eje ctions and present them in perspective of earlier work.