need help with particles, create light streak

I'm trying to create a light streak that moves through 3d space and deforms on turns. Something like this, ff to 10sec:

I thought I'ld use particles, animate the position of the emitter and the trail created by emitted particles would follow the path. Well I can't get it done because once I move the emitter, I see no constant emission of particles just blotches per frame. I managed to fill the gaps between the blotches with pSpawn by turning up position variance. But now the beam is way too thick. How do I get the emitter to emit constantly, not just a certain number per frame? Better even, how do I get this effect done in fusion? Sample comp please!

I thought I'ld use particles, animate the position of the emitter and the trail created by emitted particles would follow the path. Well I can't get it done because once I move the emitter, I see no constant emission of particles just blotches per frame. I managed to fill the gaps between the blotches with pSpawn by turning up position variance. But now the beam is way too thick. How do I get the emitter to emit constantly, not just a certain number per frame? Better even, how do I get this effect done in fusion? Sample comp please!