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background parametrization of the K +- events Erika, Roberto, Vincenzo, Patrizia. different tracking performance for the K ± events in the data and MC samples.
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background parametrization of the K+- events Erika, Roberto, Vincenzo, Patrizia different tracking performance for the K± events in the data and MC samples 4/11/06 P. de Simone
a procedure runs to monitor the bck parameters each 1 pb-1 (probability and shape of the “spurious” hits around the RECONSTRUCTED K± tracks of double tagged Km2 events .. we expect a correction factor) remind … • Probbck-hits (layer 1 -> 12) • Probbck-1hit (layer 1 ->12) • Probbck-2hits (layer 1->12) • Dcellsbck-hit ± sDcells (layer 1->12) • Tshift ± sTshift • 2002 background parameters in DB2 • 2005 background parameters … in production • SIMKBCK adds the bck hits in the MC hits list of the DHIT bank • “home-made” reconstruction of 20pb-1 of 2002 MC events to study IF and HOW this new background parametrization affects the MC efficiency 4/11/06 P. de Simone
data sample MC sample rxy (cm) t (ns) data sample MC sample + SIMKBCK t (ns) rxy (cm) rxy vertex and t K± distributions they are affected by the K± tracking efficiency shorter is the kaon path lower is the efficiency multiply Probbck-hits by 2 … 3 … … 5 !!!! 4/11/06 P. de Simone
data sample MC sample p (MeV) p (MeV) data sample MC sample + SIMKBCK p (MeV) p (MeV) pK±and psec distributions the bck parametrization does not affect in a significant way these distributions pK± psec 4/11/06 P. de Simone
data sample MC sample + SIMKBCK data sample MC sample p (MeV) p (MeV) p (MeV) p*sec distribution the bck parametrization does not affect in a significant way this distribution p (MeV) 4/11/06 P. de Simone
data sample MC sample + SIMKBCK t (ns) t (ns) etrk+vtx as a function of tK± 4/11/06 P. de Simone
data sample MC sample + SIMKBCK data sample MC sample r (cm) r (cm) r (cm) r (cm) etrk+vtx as a function of rxy 4/11/06 P. de Simone
next … • 2005 background parameters … in production • “home-made” reconstruction of 5 pb-1 of 2005 MC events ready to determine the correction factor • we are confident to be ready for the 2005 MC production • .. but .. we need also .. a new production of the 2002 MC sample 4/11/06 P. de Simone