Lucia - LAPP Phi* meeting - 3 novembre 2011 1 Correcting back to the electrons after FSR So far C Z defined w.r.t. electrons before FSR Z status = 3 and.

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1 Lucia - LAPP Phi* meeting - 3 novembre 2011 1 Correcting back to the electrons after FSR So far C Z defined w.r.t. electrons before FSR Z status = 3 and look for the first 2 children Which are the C Z if defined w.r.t. electrons after FSR ?? technically: Z status = 2 and look for the first 2 children technically: e, 

2 Lucia - LAPP Phi* meeting - 3 novembre 2011 2 So why C Z  * after FSR depend so stronger than C Z  * before FSR ? before FSR after FSR P TZ ** CZ calorimeters integrate --> the energy measured is closer to before FSR This is not true for tracks !!

3 Lucia - LAPP Phi* meeting - 3 novembre 2011 3 Data driven Systematic uncertainty on  * coming from tracking 2) Mesurer  * en fonction du Phi de la trace positive, comparer avec la même distribution pour des traces négatives (pour différentes rapidités du Z) 1) Donner un signe à  * de façon à que si il n’y a pas de bias (mais seulement des effets de résolution) la distribution soit symétrique. Réponse/suggestions de Attilio Andreazza (traduction de l’italien) Utiliser les cosmiques ce n’est pas une solution optimale car les distributions angulaires sont très différentes Utiliser des résonances (V0) n’est pas une bonne idée non plus car éventuels effets de résolution et biais sont dominés par la mesure de l’impulsion Suggestions de Attilio: Réponse de Attilio à mes questions: (Mais comment ??)

4 Lucia - LAPP Phi* meeting - 3 novembre 2011 4 Proposal for studying the systematic uncertainty coming from tracking e+ (N-)L (N-)R The systematic error results from the difference between data and MC on the difference of (N-)L and (N-)R --> look at  for (N-)L, (N-)R Study  as function of  for BB,BE, EE in data and MC. Apply in MC a possible shift and evaluate the effect on  * --> systematics ‘Physics’ is  symmetric (N-)L = (N-)R Our systematics comes from  and  Same principle for  

5 Lucia - LAPP Phi* meeting - 3 novembre 2011 5 How to continue(proposal) Discuss this ideas with the Tracking conveners (Attilio) and if OK I’llproceed In the meanwhile, if anybody interested (Ohan?) can look to the suggestion 1) of Attilio or/and any additional welcome suggestion (N-) L (N-) R e+ (N-) L (N-) R  MC-Pythia Data ( no BKG subtraction ) MC-Pythia Data ( no BKG subtraction ) (N-) L (N-) R First results (BB) : e- 

6 Lucia - LAPP Phi* meeting - 3 novembre 2011 6 Proposal for  *, Pt binning: iterative procedure? First step: make analysis with D0 binning and evaluate roughly the systematic uncertainty per bin i (  syst i rel ) Second step: compute the bin size  j for which:  stat j rel = (√1/N j ) = 0.5  syst i rel One then obtains : (+ require that  j > X  phi j  tot j rel = √(1+ 0.5 2 )  syst i rel ~ 1.2  syst i rel in principle this can be iterated Already some work done by Ohan and Vincenzo in the line with what was done by Hao (look at Phi* and Pt resolution). Do not remember if the work converged Here my proposal: First attempt (assuming  syst i rel = 0.01):

7 Lucia - LAPP Phi* meeting - 3 novembre 2011 7 ** Bin=1 Valore Initial Bin= 2.643e+04 StatRel Error=0.006151 Nratio= 2.643 Valore binNEW= 0.01189 ValoreNEW=9831 StatRel Error=0.01009 Valore binNEW= 0.01567 ValoreNEW=9487 StatRel Error=0.01027 Valore binNEW= 0.01946 ValoreNEW=9135 StatRel Error=0.01046 ** Bin=2 Valore Initial Bin= 2.401e+04 StatRel Error=0.006454 Nratio= 2.401 Valore binNEW= 0.02208 ValoreNEW=9784 StatRel Error=0.01011 Valore binNEW= 0.02625 ValoreNEW=9348 StatRel Error=0.01034 Valore binNEW= 0.03041 ValoreNEW=8911 StatRel Error=0.01059 ** Bin=3 Valore Initial Bin= 2.15e+04 StatRel Error=0.00682 Nratio= 2.15 Valore binNEW= 0.03233 ValoreNEW=9728 StatRel Error=0.01014 Valore binNEW= 0.03698 ValoreNEW=9190 StatRel Error=0.01043 Valore binNEW= 0.04163 ValoreNEW=8662 StatRel Error=0.01074 ** Bin=4 Valore Initial Bin= 1.902e+04 StatRel Error=0.007252 Nratio= 1.902 Valore binNEW= 0.04263 ValoreNEW=9667 StatRel Error=0.01017 Valore binNEW= 0.04789 ValoreNEW=9019 StatRel Error=0.01053 ** Bin=5 Valore Initial Bin= 1.667e+04 StatRel Error=0.007744 Nratio= 1.667 Valore binNEW= 0.053 ValoreNEW=9606 StatRel Error=0.0102 Valore binNEW= 0.059 ValoreNEW=8867 StatRel Error=0.01062 ** Bin=6 Valore Initial Bin= 1.459e+04 StatRel Error=0.008279 Nratio= 1.459 Valore binNEW= 0.06377 ValoreNEW=9524 StatRel Error=0.01025 Valore binNEW= 0.07131 ValoreNEW=8697 StatRel Error=0.01072 ** Bin=7 Valore Initial Bin= 1.273e+04 StatRel Error=0.008862 Nratio= 1.273 Valore binNEW= 0.07493 ValoreNEW=9588 StatRel Error=0.01021 Valore binNEW= 0.08278 ValoreNEW=8968 StatRel Error=0.01056 ** Bin=8 Valore Initial Bin= 1.157e+04 StatRel Error=0.009298