[Rivet] lifetimes in rivet

[Frank Siegert]

Jonathan Butterworth, Wednesday 07 April 2010:
> All one is really doing here is correcting for a well-known
> exponential, so I think it's pretty sound. One wouldn't do this for
> anything but particles which are metastable, lifetimes > 10ps or so.

Sorry that I'm slow here, but don't you have to correct for their decay 
products as well? Simplified example: Measuring charged multi in |eta|<2, 
and you want to correct for all K_S as stable. Now your detector might 
contain pi+ pi- from a K_S decay, possibly in |eta|<2, possibly not. Don't 
you have to use a model for K_S decays to correct for that increase in 
charged multi if you claim a measurement with *all* K_S stable?

This is purely out of interest. I agree that in such cases we shouldn't do 
this in the Rivet analysis.

Frank