Linear change and minutes variability of solar wind velocity revealed by FAST

Observation of Interplanetary Scintillation (IPS) provides an important and effective way to study the solar wind space weather. A series IPS observations were conducted by Five-hundred-meter Aperture Spherical radio Telescope (FAST). The extraordinary sensitivity wide frequency coverage make FAST ideal platform for studies. In this paper we present some first scientific results from with L-band receiver. Based on velocity fitting values September 26-28, 2020, found that decreases increasing linearly, which has not yet been reported in literature. And have also detected a variation timescale 3-5 minutes, imply slow change background wind, co-existence high- low-speed streams, or reflect quasi-periodic electron-density fluctuations.