New Cell Energy Density weights and scale factors parameterization MC09 Belen Salvachua High Energy Physics Division Argonne National Laboratory Sebastian Eckweiler Institut fur Physik Johannes-Gutenberg-Universitaet

2 The Goal Calculate new Global Cell Energy Weights for: –New MC09 simulation –Test weights for AntiKt jets and Cone jets Calculate new Re-scale factors with Num. Inv. technique for all jet collections on new AODs Store constants into database and use them as default for MC09

3 Use Validation Samples to calculate the weights Dataset NameEvents Available mc09_valid J0_pythia_jetjet.recon.ESD.e344_s561_r731/91000 mc09_valid J1_pythia_jetjet.recon.ESD.e344_s561_r731/64250 mc09_valid J2_pythia_jetjet.recon.ESD.e344_s561_r731/61000 mc09_valid J3_pythia_jetjet.recon.ESD.e344_s561_r731/98250 mc09_valid J4_pythia_jetjet.recon.ESD.e344_s561_r731/98250 mc09_valid J5_pythia_jetjet.recon.ESD.e344_s561_r731/99000 mc09_valid J6_pythia_jetjet.recon.ESD.e344_s561_r731/ mc09_valid J7_pythia_jetjet.recon.ESD.e344_s561_r731/97500 mc09_valid J8_pythia_jetjet.recon.ESD.e344_s561_r731/no events available Thanks to Iacopo Vivarelli for the production of these samples

4 PROBLEM: Retrieving EM scale cell energy AntiKt jets were not in the validation ESDs –need custom reconstruction Use signal state to retrieve EM scale: –Tower jets seem fine –Topo jets were providing incorrect Cell EM energy AntiKt4Topo AntiKt4Tower Extra weight for Topo jets energy

5 Problem and Solution Problem: –By default make_StandardJetGetter('AntiKt',0.4,'H1Topo').jetAlgorithmHandle() was taken Calibrated Topo Clusters Solution : Specify input collection  Uncalibrated Topo Clusters –myalg0=make_StandardJetGetter('AntiKt',0.4,'H1Topo').jetAlgorithmH andle() –myalg0.InputCollectionNames=['CaloTopoCluster'] And commented out: doTopoClusterLocalCalibration = False Jobs were re-sent to the grid  Correct EM energies !!! Thanks to Pier-Olivier and Pierre-Antoine

6 New H1 weights ! ---- AntiKt4Topo ---- AntiKt4Tower ---- Cone4Topo ---- Cone7Tower Only large differences for AntiKt4Tower in very low statistic region Previous releases we used Cone7Tower weights for ALL collections. Since we are mainly using now AntiKt, We propose to keep AntiKt4Topo weights for ALL MC09 collections.

7 Linearity and resolution without Num. Inversion AntiKt4Topo NO num. inversion

8 Numerical Inversion We decide to use AntiKt4Topo H1 constants for all collections However, the Numerical Inversion fits provided by Sebastian show difficulties to find the proper parameterization. –Large fluctuations on the function. That did NOT happen before (see next 2 slides)

9 OLD H1 (from Cone7Tower): AntiKt4Topo

10 New AntiKt4Topo H1

11 Problem of fluctuations with new constants OLD constants calculated with Cone7Tower and applied to all Jet Collections NEW constants calculated with AntiKt4Topo Difference could be due to: –Cone size –Topo vs Tower –Change on the simulation/reconstruction We re-did the fits for new constants for Cone7Tower –Similar to OLD MC08 Cone7Tower  NOT due to simulation/reconstruction New H1 From AntiKt4Topo New H1 From Cone7Tower

12 New H1 From AntiKt4Topo New H1 From Cone7Tower New H1 From AntiKt6Topo New H1 From AntiKt6Tower Change Cone size and input Difference due to: Input constituents

13 Between AntiKt 4 or AntiKt 6: Differences are minimal. AntiKt4Topo weights for MC09

14 Numerical inversion in mc09 Applying the new mc09 cell weights: Improved response: –Quicker rise and closer to 1 –But: significant changes in shape increased data - fit discrepancy Several disadvantages in procedure with fitted histograms: –no physical motivation –Shape depends on η-ranges: would need several parameterizations polynomial up to arbitrarily high order also unsatisfactory difficult to automatize

15 Results - Mc09 Discrepancies directly propagated to response Nevertheless, scale within ± 2% : –If physical fluctuations  larger deviations in different sample expected

16 Looking for improvements Basicall there are 2 classes of possibilities: –Stick to parameterizations: - needs lots of manual effort needed + only trivial changes in software needed –Direct use of TObjects / TGraphs: (Get scale factor with h->GetBinContent() or similar) + would be easier to automate - eventually sensitive to statistical fluctuations Possible combination of both methods: smoothed Graphs

17 Looking for improvements TGraphSmooth offers several methods to smooth Graphs Easiest possibility: smooth points using a given Kernel-function p(x,y) –Smoothed values: Example for p(x, xi) : Gaussian with mean x Kernel-function parameters need some adjustment: e.g. width of the Gaussian Sensible ‚upgrade‘: p(x,xi) -> p(x,xi) / σi to incorporate uncertainties

18 Looking for improvements TGraphSmooth offers several methods to smooth Graphs Easiest possibility: smooth points using a given Kernel-function p(x,y) –Smoothed values: Example for p(x, xi) : Gaussian with mean x Kernel-function parameters need some adjustment: e.g. width of the Gaussian Sensible ‚upgrade‘: p(x,xi) -> p(x,xi) / σi to incorporate uncertainties Adjust to give a reasonable ‚version‘ of χ 2 /#points χ 2 /#points # entries

19 First results First results look promising Scale linear within ±1% Small deviations from ‘perfection‘: ~1% rise at low energies Nevertheless: seems to be the way to go! 19

20 Summary and Conclusions New global cell energy density weights for MC09 –Calculated using AntiKt 4 Topo Jets Numerical Inversion factors will be use to recover JES –Calculated for all Jet Collections with fitting fuctions Still TO DO: –Check energy density weighs and JES factors with other samples –Store them into database to be use in standard production –Document how the weights and factors have been calculated –Understand origin of fluctuations –Examine different techniques / parameters for smoothing Find technical way to implement into JetCalibTools TH2‘s from database already used in local hadron calibration Could encode TGraphs in TH2‘s to simplify Athena modifications

21 BACK-UP

22 Reconstruction Details: JetSampling calculation PackageTag Athena Release Reconstruction/Jet/JetEventJetEvent (from release) Reconstruction/Jet/JetEventAthenaPoolJetEventAthenaPool (from release) Reconstruction/Jet/JetEventTPCnvJetEventTPCnv (from release) Reconstruction/Jet/JetUtilsUpdate to JetUtils Reconstruction/Jet/JetRecToolsJetRecTools (from release) Database/AtlasSTLAddReflexAtlasSTLAddReflex (from release) Reconstruction/Jet/JetCalibUpdate to JetCalib

23 OLD weights: Cone7Tower

24 Linearity and resolution without Num. Inversion Cone7Tower NO num. inversion