Emmanuel Busato Jet/Met meeting 12/19/2002 Goal : Correlation between f90 and other variables for 0.5 cones ? - for jets constructed without CH - for jets constructed with CH Run (  events) reconstructed with p Update on noisy jet study

Correlations for jets constructed without CH Keep only jets that pass standard ID cuts  0.05 < EMF < 0.95  n90 > 1  HotF < 10 No trigger requirement

EMF and FHF vs f90 These jets have FHF and EMF identical to jets with smaller f90. Noisy jets come from both EM and FH part of the calo

Apparently no phi dependence. High f90 jets are mostly in ICR and CC. Phi and Eta vs f90 Phi Eta F90 Eta F90>0.8 F90<0.8

EtaW and PhiW vs f90 EtaW PhiW F90 Jets with EtaW or PhiW bigger than 0.3 are mostly « bad jets »

Nitm and n90 vs f90 « bad jets » have f90 big because n90 is big. Few of them (10  ) are made of a large number of towers (>80) and come from merging. What about split/merge for other jets ? necessarily merged jets (R = 0.5 cones only have  80 towers)

Splitting and merging No split/merge Only merged Only splitted - All kind of jets contribute to low f90 population (f90<0.8) - Only merged jets contribute to the big f90 population (f90>0.8)

Correlations for jets constructed with CH  Correlation plots look very similar to those for jets without CH ( )  How does f90 behave with split/merge and CHF ? CHF< <CHF<0.4 CHF>0.4 No split/merge Only merged jets Only splitted jets

 only merged jets see their distribution change as CHF increases (proportion of jets with f90<0.7 decreases) If we assume that jets with CHF>0.4 are bad, f90 depends more on whether a jet has merged than on its quality (good or bad)  For CHF>0.1 : f90 distribution gives two distinct populations of jets, the first one with f90  corresponding to jets without merging  the second one with f90  corresponding to merged jets