slow a particle to a stop

[ldotchopz]

This is probably very simple but i can't think of a way to do it.

I have a particle being emitted from a tyicon with speed dirving it. but i want the particle to come to a gradual stop. keyframing the speed does nothing. and the slow operator screws up the noise pattern have of the tyspline.

Is there a way to just slowly bring it to a stop?

Thanks