I'Tsukerman ITEP, Moscow

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I.Tsukerman ( ITEP, Moscow) Russian ATLAS EVO
meeting, CERN, April 23,2008

• News about jets and Etmiss in 2008
• List of helpful ATLAS Web sites for jets and
  Etmiss
• Jet/Etmiss working group in ATLAS
• List of presentations at Jet/Etmiss meetings
  in 2008
• Extraction from J. Proudfoot talk during
  ATLAS week
• ITEP group activity and JET-5 CSC note

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List of helpful ATLAS Web sites for jets and
Etmiss

• https//twiki.cern.ch/twiki/bin/view/Atlas/JetEtMi
  ss - main page
• http//indico.cern.ch/categoryDisplay.py?categId4
  92 meetings
• http//indico.cern.ch/conferenceDisplay.py?confId
  26943
• Last hadronic calibration Workshop,
  14-16.03.08, Arizona, USA
• http//indico.cern.ch/conferenceDisplay.py?confId
  20499
• J. Proudfoot summary talk about jets, Feb.
  2008, ATLAS Week
• http//indico.cern.ch/conferenceDisplay.py?confId
  27169
• Jet/EtMiss performance meeting, Feb. 2008
• https//twiki.cern.ch/twiki/bin/view/Atlas/AtlasTe
  chnicalPaper -
• ATLAS Detector Paper. Look at Parts 10.5 and
  10.6.

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List of Jet/EtMiss meetings in 2008

• April 2008
• 08 Jet/MissingEt Reconstruction Performance
  Meeting
• 02 Jet/EtMiss Phone Conference
• March 2008
• 19 Jet/EtMiss Phone Conference - CANCELLED!
• 14 - 16 4th ATLAS Hadronic Calibration Workshop
• 10 CSC Etmiss short note discussion about the
  section of fake MET reduction method.
• 05 Jet/EtMiss Phone Conference
• February 2008
• 13 Jet/Missing Et Performance Meeting
• 12 Etmiss CSC Note meeting
• 07 Jet in-situ calibration CSC note
• 06 Jet/EtMiss Phone Conference
• January 2008
• 23 Jet/EtMiss Phone Conference

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• Wednesday 23 January 2008 top
• 1700 News (10') ( Slides )
  
  Jimmy/Peter
• 1710 MET_CellOUT Calibration (20') ( Slides )
  Anna Phan
• 1730 Forward Jets, Missing Et, Pile-up calo
  time (20') Pierre-Antoine Delsart
• 1750 Using Track Jets to reject Fake EtMiss
  (20') (Slides ) Stephanie Majewski
• 1810 High Pt Jet Calibration using Multi-Jet
  Balance (20') (Slides) Koji Terashi
• 1830 Tuning of Jet Minimum Pt for MET
  Calculation (20') ( Slides) Xin Chen
• Wednesday 05 March 2008 top
• 1700 Preview of Moriond Presentation (25') (
  Slides ) Ulla Blumenshein
• 1725 Comparison of QGSP_BERTEMV and QGSP_BERT
  (20') Frank Paige
• 1745 Status of software for Release 14 (20') (
  Slides ) Rolf/P-A
• 1805 Input received on who is doing what (10')
  Jimmy Proudfoot
• 1815 Hadronic calibration workshop at Tucson
  (10') Peter Loch

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• Wednesday 02 April 2008 top
• 1700 Upcoming chances in the MET trigger slice
  (15') Diego Casadei
• 1715 Using tracker information to estimate the
  jet energy scale error (15')
• (Slides) Vincent Francois Giangiobbe
• 1730 Status of jet software for 14.X.0
  jet/particle jet merger and FastJet
• integration (15') (Slides ) Rolf
  Seuster
• Tuesday 08 April 2008 top
• 1400 Out-of-cone energy corrections for MET
  (20') (Slides) Xin Chen
• 1420 New Tools for Trigger Robustness (20')
  (Slides) Swagato Banerjee
• 1440 Track-based jet response corrections (20')
  (Slides) Zachary Marshall
• 1500 Jet energy scale corrections to
  semileptonic b-jets (20') (Slides )
• David Lopez Mateos
• 1520 Jet energy corrections for pile-up (20') (
  Slides ) David W. Miller

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Wednesday 13 February 2008 top 1400
Calibration of High Pt Jets (20') ( Slides ) Koji
Terashi 1420 Effect of Tile Electronics failures
on Jet Measurement (20') Philippe Mermod 1440
Pulse Shape, Digital Filtering and Signal
Reconstruction in Liq. Argon (30') Guillaume
Unal 1510 Jet Algorithm Study in the presence of
pile-up (15') Mario Campanelli 1525 Jet/EtMiss
Monitoring during FDR-1 (15') ( Slides ) Martina
Hurwitz 1540 Coffee Break 1610 Jet/Etmiss EDM
Past, Present and Future (25') Peter Loch 1635
Software News and Documentation (25')
Pierre-Antoine Delsart 1700 Status of CSC Note
Jet5 Peter
Loch 1715 Status of CSC Note Jet6 Jet
Calibration Strategies (15') Iacopo
Vivarelli 1730 Status of CSC Note Jet10 (in situ
calibration) (15') Jimmy Proudfoot 1745
Status of CSC Note Jet16 (15') Donatella
Cavalli 1800 Status of CSC Note Jet8 (Single
hadron scale) (15') Mark Hodgkinson 1815 Status
of CSC Note Jet16 (15') (Slides) Junichi Tanaka
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ITEP group activity for JET-5 CSC note(parts
about forward jets and jets in minimum-bias
events)

• Jet characteristics in VBF Higgs and minibias
  events
• Multiplicities, kinematics, Etresolution and
  biases
• Reconstruction efficiencies and impurities
• ATL-COM-PHYS-2007-083
• All jet collections are adequate for VBF Higgs
  searches
• Hovewer, cone size of 0.4 is preferrable due to
  pile-up
• Some update 2008 studies with release 13, see
  below

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Jet reconstruction and analysis algorithms

• 8 jet reconstuction collections (4 true)
• Conventional and Topo C (R0.7), C4 (R0.4) kt
  (D0.6 and 0.4)
• Run on projective towers (or Topoclusters) and
  truth particles
• Limitations Etgt7GeV, h lt5
• Private algorithm correspondence between true
  
• and reconstructed jets, ROOT
• Default matching DRsqrt((h(rec)-h(true))2(
  f(rec)-f(true))2)ltDR0
• DR00.25 for R0.7 0.2 for D0.6 and 0.15 for
  R0.4 to avoid double-matching
• The ROOT-based algorithm was renewed for 13.0.3
  AANT
• Jet properties Jet/EtMiss meetings (for JET-5
  CSC Note)
• Tagging, veto Higgs WG meetings (for HG-3 and 4
  Notes)

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Fraction of events with jets (single MB,
Etgt20GeV)
C(0.7)
C(0.7) Topo
C(0.4)
C(0.4) Topo
Kt(0.4)
Kt(0.4) Topo
Kt(0.6)
Kt(0.6) Topo
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Jet reconstruction efficiency (Etgt10 GeV)
13.0.33 75K events (dataset 5001, tid 17715)
Barrel/EC and EC/FCal cracks are seen
Low efficiency for Tower jets, better for Topo
jets
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Reconstruction efficiency vs Et for PYTHIA
VV?H(C4 Tower and Topo jets, Etgt20GeV DS5322,
TID17852)
Strong increase of efficiency at low Et for C4
Tower
Tower
forward jets
central jets
Topo
forward jets
central jets
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Reconstruction efficiency vs h for PYTHIA
VV?H(C4 Tower and Topo jets, Etgt20GeV DS5322,
TID17852)
Strong increase of efficiency in FW region for C4
Tower
Tower
Topo
Reason of the increase 1 GeV cell threshold in
13.0.3 (was 2)
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Backup slides summaries of some talks during
February ATLAS week
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High PT Jet Calibration
K. Terashi, M. Kaneda, S. Asai ICEPP,
University of Tokyo Aim Develop data-driven
calibration technique for jets with PT up to 1
TeV using 1 fb-1 of data

• Calibration of high pT jets at TeV range is a
  challenging and important task for new physics
  search and QCD studies
• Work in progress towards establishing jet energy
• scale at 0.5-1 TeV range using early data
• ? Multi-jet pT balance method
• ? Track-based Method
• Results encouraging (while more studies on
  systematic uncertainties needed) for extending
  the pT range beyond 1 TeV

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Effects of Tile electronics failure on jet
measurement Philippe Mermod

• TileCal accounts for only 20-40 of jets Pt (the
  rest is taken by LAr)
• In a realistic case, significant effects only
  for processes involving
• very highPt jets (gt100 GeV)
• Nonlinearity of jet energy deposition
• Deal with fake MET
• A whole region is dead exclude highpt jets
• Many spread channels must live with

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Signal reconstruction in LAr G. Unal (CERN)
Basics of LAr readout Basics of Optimal
Filtering (OFC) Pulse shape predictions
Effect of pileup
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Conclusion OFC is a simple, fast, linear
method to estimate amplitude which allows
reduction of electronicspileup noise Input
ingredients Physics pulse shape gt main
challenge is to reach the ultimate EM accuracy on
constant term Autocorrelation to get best
pileup noise reduction Can be measured from
data Model being put in place to get the proper
ingredients from data Including pedestal shift
and effect of machine time structure We have
some time before defining the ultimate strategy
for high luminosity pileup But pileup effect
will already be visible from the very beginning,
especially in the end-cap regions Implications
on Jet/Etmiss Not the same ultimate accuracy as
electrons But sensitive to high eta part and to
collective effect over large area Many
questions are worth to study Effect of E/sigma
cut gt signal is a function of luminosity (and
thus probably also final jet calibration) Can
we make any use of time and quality etc..
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• Jet studies with pileup events
• Mario Campanelli (University College London),
  K.Gering, J.Huston (MSU)

The presence of 3 pileup events (already likely
in 2008) makes conclusions of first study even
stronger. Already more solid from the theoretical
point of view, Kt04 and SISCone have shown better
performance than the Atlas cone for all tests
performed so far.
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Jet monitoring in FDR1 Martina Hurwitz FDR1 was
useful software exercise From point of view of
someone who is not an expert, it was
interesting to see how monitoring will work
Plans for jet monitoring trigger aware
monitoring split off some plots into expert
plots. make a short summary implement DQMF
document the plots Data is going through bulk
reconstruction good chance to exercise analysis
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Status of Rel 14 Jet EDMP. Loch (Arizona)

• Have dedicated nightly (MIG4)
• New Jet class under test
• New converter for ParticleJet and Jet under test
• Signal state for CaloCluster and Jet coded but
  not yet tested
• Only in standalone test program!
• Other changes needed
• Split store/TP separation may not be in place for
  14.0.0
• 14.0.1/14.1.0 more likely
• Review of status next Monday
• Well see what we can get into 14.0.0 then
• Lots of new stuff
• Expect some (minor) instabilities!
• Help us by reporting problems
• Maybe even provide solutions/fixes!