%CERTIFY%

Jet Energy Scale and Resolution Subgroup

Convenors: Fabrice Balli, Chris Young

Introduction

The Jet Energy Scale and Resolution group is a subgroup of the JetEtMiss group dedicated to measuring the jet energy scale and energy resolution, as well as their uncertainties and correlations.

Current recommendations for physics analyses

See the JetCalibrationToolsForPhysicsAnalyses and JetUncertainties2012Final twiki pages. For dijet specific analyses, some useful info is on the JetStudies2012 page. For the resolution : use ApplyJetResolutionSmearing-00-01-02 and JetResolution-02-00-02. Further instructions at JetEnergyResolutionProvider2012 and ApplyJetResolutionSmearing.

Meetings and Mailing Lists

• Jet/EtMiss Working Group meetings: Every week on Wednesday afternoon
• Jet calibration and resolution meetings: Every week on Tuesday afternoons.
• Jet calibration and resolution e-mail list (e-group): atlas-cp-jet-calibration Archive

Current and Future Analyses

Below a list of current analyses happening within the group as well as possible future analyses are listed. Either list may not be complete, please let us know if that is the case. For ongoing analyses, a (possibly incomplete) list of people working on them, and a twiki/e-group (when available) are listed.

Both analyses in progress and future projects need manpower (ongoing analyses often need to be carried over to new datasets, so do not be discouraged if some people are already listed). If you are thinking of starting a new project or joining an ongoing one, we hope the information found below is helpful in making your choice. Please also contact us to further discuss your interest.

High priority tasks

• Pile-up systematic estimation
• Multijet balance in-situ analysis
• Recommissioning of origin correction
• Recommissioning of punch-through correction
• Cross-calibration for detector and energy changes btw 2012/15
• eta-intercalibration with early Run2 data : dedicated page EtaIntercalibration2015

Remaining Run I analyses

Analysis	Active People
Final JER Z+jets	G. Lefebvre
Final JER gamma+jets	A. Olariu
Final JER multijets	W. Leight
Final JER Noise term	C. Sawyer, C. Young
Final JER combination	B. Malaescu

Run I CONF and paper

Analysis	Editors	Link
CONF MC JES & Uncertainties	C. Sawyer, C. Young	pdf
CONF GSC	R. Camacho, J. Taenzer
CONF Eta intercalibration	J. Lacey, A. Pilkington
CONF V+jets	S. Lammers, M. Vetterli, P. Starovoitov
2012 JES/JER paper	B. Malaescu, D. Gillberg

Run II preparation

MANPOWER NEEDED -- even if there is a name for the subject you may be interested in, there is still a lot of work to do in each of these areas.

Analysis	Active People	Deadline	Link
xAOD migration - Jet calibration tool	J. Taenzer	30/10/2014
xAOD migration - Jet uncertainty provider	S. Schramm, DeMarco	30/10/2014
xAOD migration - JVT pile-up suppression	P. Nef (?)	30/10/2014
xAOD migration - Pile-up correction and systematics	S. Alkire	30/10/2014
xAOD migration - Origin correction	NOBODY	30/10/2014
xAOD migration - MC JES and eta calibration	G. Marceca, J.-L. La Rosa	30/10/2014
xAOD migration - GSC	J. Bossio	30/10/2014
xAOD migration - Eta intercalibration	M. Queitsch-Maitland, F. Balli	30/10/2014
xAOD migration - Z+jet	J. Horton, A. Dattagupta, P. Starovoitov	30/10/2014
xAOD migration - Gamma+jet	J. Beare, A. Olariu	30/10/2014
xAOD migration - Multijet balance	NOBODY	30/10/2014
xAOD migration - Single particle	B. Axen	30/10/2014
xAOD migration - Combination	B. Malaescu	30/10/2014
xAOD migration - Jet Energy Resolution	S. Farrell	30/10/2014
Cross-calibration 2012 vs 2015 data
Punchthrough correction

NB: the active members responsible for xAOD migration are also responsible for re-running the whole analysis in November and have DC14 recommendations for end-of-November.

Analyses in Progress

NEEDS AN UPDATE

Sub-topic	Analysis	Active People	Twiki/E-group
Pile-up Corrections	Monte Carlo Truth-level Offset	J. Backus Mayes, C. Sandoval	twiki
	JVF-based Correction	J. Backus Mayes
	Offset Calculation using Jet Areas	L. Bryngemark
	Offset Calculation using Random Cones	P. Manning
	Offset validation with Track-jets	J. Backus Mayes, G. Zevi della Porta
	Offset validation with +jet Balance	A. Tanasijczuk
Inclusive JES	Monte Carlo Absolute JES	T. Sumida
	Validation using +jet Balance	L. Kogan, F. Vives	twiki
	Validation using +jet MPF	J. Kvita, A. Tanasijczuk	twiki
	Validation using di-jet ( intercalibration)	G. Brown, D. Gillberg, R. King, V. Kus, J. Lacey, C. Suhr	twiki
	Validation using Z+jet	J-F Grivaz, J-B Sauvan
	Validation using Multi-jet Sample	X. Chao, K. Terashi	twiki
	Validation using Tracks in di-jet Sample	F. Paige
	Validation using Tracks in Z+jet Sample	M. Shapiro
	Combination of Measurements	C. Doglioni, D. Gillberg, B. Malaescu
Non-isolated Jets	Isolation Definition	C. Doglioni, D. Gillberg, H. Reisin, M. Swiatlowski	twiki
	JES Validation using Tracks	K. Terashi
Quark/gluon JES	Monte Carlo Systematics	D. Lopez Mateos, S. Adomeit, A. Picazio
	Validation Using +jet Balance	F. Vives
	Validation Using di-jet Balance	H. Reisin
b-jet JES	Monte Carlo Systematics	K. Loureiro
	Semileptonic JES in MC	D. Lopez Mateos, K. Mercurio, A. Yen
	Validation of JES using	G. Compostella, G. Cortiana
	Validation of JES using di-jet Sample	D. Lopez Mateos, K. Mercurio
	Validation of JES using Z+jet Sample	D. Lopez Mateos, A. Yen
	Validation of JES using +jet Sample	K. Ikematsu,
Jet Energy Resolution	Jet Energy Resolution Measurement using di-jets	G. Otero, S. Sacerdoti
	Improvement of Resolution using	G. Otero, H. Reisin
	Improvement of Resolution using Calorimeter Props (GS)	(uncovered currently)	twiki
High pT Jets	Performance and Calibration	C. Issever, S. Schramm	twiki
	Study of Punchthrough Effects using dijets	S. Gupta
	Study of Punchthrough Effects using D*	T. Huffman
	Study of Punchthrough Effects using gamma+jet	V. Pleskot
	Multijet Calibration	G.Vardanyan
	High pT Jet Cleaning	V. Pleskot, A. Saddique, O. Endner, F. Guescini, A. Picazio, D. Salek

Potential Future Projects

Sub-topic	Analysis
Pile-up Corrections	Offset validation with dijet balance
	Offset derivation or validation using MC with overlaid ZB data
	Correcting for the effect of pile-up on the jet mass (with substructure group)
	Study of improved variables for parametrizing pile-up
	Dependence of the offset on jet properties
	Use of tracks to correct for the effect of pile-up on the jet direction
Inclusive JES	Measurement of JES/JER Using Hadronic Ws from top
Non-isolated Jets	JES Correction for Different Topologies
Quark/gluon JES	JES Correction vs Likelihood Variable
Heavy flavor JES	Validation using
	Validation using Tracks and Reconstructed C-Hadron Decays
	JES Correction for C-Hadron Decays
Jet Energy Resolution	Resolution Measurement using hadronic Ws
	b-jet Resolution Measurement using top mass reconstruction
	Angular Resolution Measurement (and pile-up dependence)
	b-jet Resolution Monte Carlo Study
	b-jet Resolution using di-jet Sample
	b-jet Resolution using +jet
	b-jet Resolution using Z+jet
	b-jet/c-jet Angular Resolution Measurement (and pile-up dependence)

Analysis Tools and Common Selections

D3PD Information 2011 samples

See the AnalysisData2011 page and the JetEtMiss D3PD page.

Jet E_T^miss samples

• Release 17 data and MC11a
• MC11b
• MC11c
• s1273 means full simulation in all eta regions. s1310 means frozen showers in the forward region.

Recalibration and Smearing Tools

Due to testing of multiple calibration baselines, it is recommended to recalibrate jets from the D3PD using the guidelines found here: Jet Calibration Tools For Physics Analyses

Jets are also required to be smeared in the Monte Carlo, to allow for data/MC agreement, as calculated using release 16. Preliminary results with release 17 suggest that the smearing values may change slightly (for the better) in the new release. However, those changes have not been propagated to the tools above, and they will not modify the interfaces of the tools (being transparent to analyses).

Recommendations for the in-situ JES analyses

For the preliminary Moriond JES.

Calibration

The final calibration is in the ApplyJetCalibration package. The recommended tag is ApplyJetCalibration-00-03-35 (link to SVN)

Jet response fitting tool

See JetResponseFitter.

Reference region

|η|<0.8

Jet cleaning

''isBadLoose'' (to be updated for the final JES measurement, post Moriond).

Example code

See the JetEtMissAnalysis twiki. Example code to run on xAODs : SoftwareTutorialxAODAnalysisInROOT

Notes, papers, and documentation 2012

See this Twiki page

Notes, papers, and documentation 2011

Many of the CONF notes currently being developed have had previous versions, listed below in the twiki linked from the JetEtMiss main page. New CONF notes based on the full 2011 dataset will be listed here as they become available.

• CONF Notes
• Jet Inputs
• Jet Algorithms
• Jet Calibration Methods

---

Major updates:
-- DagGillberg - 06-Dec-2011 -- DavidLopezMateos - 04-Jan-2012 -- FabriceBalli - 08 Oct 2014

%RESPONSIBLE% FabriceBalli
%REVIEW% Never reviewed