Hi JH, I have diagnostic histograms showing the track vertex as defined in our reconstruction code. You can find a typical plot (FS @ 12A427) here: http://www.nbi.dk/~ouerdane/weakday/trackVertex.gif showing the track vertex of pion tracks that made it through the FFS (from K0s). I applied the cuts I applied in my pion analysis. But I understand your question and that might be an important one. It all depends on the angular resolution at the entrance of D1 and Claus has studied that in more details for his thesis. For what we are dealing with here, the way to go I think (which I have not done) is to check the width of the same distributions but from a simulation with pion as input, compare those widths to the exprimental ones and smear the track vertex at the simulation level for pions from K0s and lambdas accordingly. I don't know how much it's gonna change the result though. Since it's gonna make the sharp peaks you see on the plot broader and flatter, I guess I would accept fewer pions and therefore the contamination wouldn't be as big. Again, I repeat, my estimation is I think overestimated, I don't think we miss many original tracks because of our resolution and the same would apply anyway for real background tracks. but I can make a quick check tomorrow with the smearing I'm talking about. Djam -- Djamel Ouerdane ------------------------------------------o | Niels Bohr Institute | Home: | | Blegdamsvej 17, DK-2100 Ø | Jagtvej 141 2D, | | Fax: +45 35 32 50 16 | DK-2200 Copenhagen N | | Tel: +45 35 32 52 69 | +45 35 86 19 74 | | http://www.nbi.dk/~ouerdane | | ouerdane@nbi.dk | o---------------------------------------------------------o _______________________________________________ Brahms-soft-l mailing list Brahms-soft-l@lists.bnl.gov http://lists.bnl.gov/mailman/listinfo/brahms-soft-lReceived on Thu Sep 2 14:11:56 2004
This archive was generated by hypermail 2.1.8 : Thu Sep 02 2004 - 14:11:59 EDT
