The producer module should be in release CMSSW_1_6_0. It's now located in

RecoVertex/V0Producer

The latest tags (as of today) for V0Producer are V00-00-03 (V0Producer) and V00-00-04 (DataFormats/V0Candidate.)


Until this point, I've been using filter modules to prune any events with nuclear interactions, etc. I now am simply looping over all the tracks and attempting a vertex fit using KalmanVertexFitter (using track parameter smoothing) for all oppositely-charged track pairs. This results in a significant slowing in compute time per event for high-multiplicity samples, so one of my next tasks is to implement some cuts that will be applied to the track collection before attempting vertex fits.

I am currently working on simulating some b-jet samples so that I can try to reconstruct these. I tried some initially after I changed the producer to loop over the tracks, but the lambda peaks were unusually broad; some reconstructed lambdas in fact had an invariant mass that was lower than the sum of the proton and pion masses, which is of course impossible.

I will post more when I know more about this.

The good news is that, even on high-multiplicity b-jet samples, my code is stable, although slow. This was pretty much what Steve Wagner was worried about, and as there are no showstoppers, I am fairly sure that the code will be in 1_6_0.