A nonthermal collimated ejection observed with the Nobeyama Radioheliograph

We have observed with the Nobeyama Radioheliograph a microwave collimated ejection that moved up to 1.3 x 10(5) km above the solar limb at an average speed of approximate to3000 km s(-1). Although the Yohkoh soft X-ray telescope pointed to another active region and therefore no soft X-ray data was available, the apparent length and width of the ejection were consistent with those of typical soft X-ray jets, but its velocity was significantly higher than that of soft X-ray jets. The microwave ejector had a bipolar or helical, closed magnetic structure that seemed to be tied to the chromosphere by its double footpoints and was located above the intense main microwave flare source with which hard X-ray double footpoint sources were associated. Association of an intense meter-wave type III burst with the impulsive peak of the microwave flare suggests that magnetic fields were opened outside the microwave ejector composed of closed loops. Simultaneous observations at 17 and 34 GHz showed that the microwave emission from the collimated ejector was nonthermal. High-energy electrons in the ejector had the same origin as those in the main flare source. It was also accompanied by an Halpha surge with a speed of 100-150 km s(-1), and the surge moved up to roughly the same height as the microwave ejector. We suggest that the microwave collimated ejection was caused by an apparent motion driven by successive injections of high-energy electrons into preexisting, higher elongated loops.