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Higgs to WW Analysis inCDF and ATLAS
R StDenis
Higgs to WW CDF and ATLAS
•Reproduction of Previous Results:Identifying, datasets, Rows and columns•Data Access and Strategy•Standard Candle: Z) •Shining the Light on CDF•Plans for ATLAS
Higgs to WW UpdateReproduction of Note 7708 Results
–The yields of the previous 360pb-1 H->WW->llanalysis have
been reproduced apart from:– some unresolved queries on the Phoenix cuts – the fake estimate is taken as a scaling factor from the old analysis– some unresolved queries on stubless muons– plug data has not been included
–Each cut yield has been reproduced number by number for a Higgs Mass=160GeV
Rows and ColumnsReproduction of Note 7708 Results
Rows: different parts of the detector, separated by cracks:What are the Rows for ATLAS?
Columns: Events surviving each Cut.
LeptonIDLeptonIsolation
Jet VetoMissing Et
Muon Reco. Efficiency as EtaRome (Athena 10.0.4)
And datasets…Reproduction of Note 7708 Results
Dilepton azumuthal separation, ll
# e
vents
/ p
b-1
/ 0.4
(22.5
o)
(To be phased out)
TopNtuple
StNtuple
‘MakeClass’ Based (To be phased out)
Object Based
Validation in
Progress
< >
Full Reco
Data Stream: Et>18
MC: Sig or BkgIe. H->WW
Atlas TagDB will have Trigger
Looking at AvailableAtlas MC DataSets
ObjectSelection Code: e,mu, MET,Jet
DtupleMTuple
Data Flow
Zee
ObjectSelection Code:
E,mu,jet,Met
Dtuple
Hww>llSelection Code, weighting:Cuts: Mll, Isolation
Hww>llSelection Code:
Cuts: METd(L-jet)
Z0)Proves analysis
Z0Bkg
• Object Selection: tricky trigger efficiencies, MC/Data calibration of reconstruciton efficiency
Data Flow – and Strategy
Shining the Light on CDFZ to ll Crossection*BR measurement
–In all channels:CEM-CEM,CEM-PLUG,PLUG-PLUG,CEM-CMU(X),CEM-CMUP, CMU(X)-CMUP (27 types) etc.–Datasets based on trigger: Central Electron >18, Cmu >18, Plug +MET, CMX>18–Good run lists–Trigger Efficiencies (measured from Z0)–Reconstruction Efficiency relative to MC (measured from Z0)
Shining a Candle on CDFZ to ee (tight, central)
*BR: 269.06 ±3.33(stat) ±2.11(sys) ±15.87(lum) Note 7708: *BR: 259.3 ±3.3 (stat) ±5.4 (sys) ±15.4
(lum)
Oops!: applied a correction twice
More Bugs Scurry
Combined CMhUP-CM(UP/X/P/IO)
*BR: 284.3 ±6.63(stat) ±9.87(sys) ±16.8(lum) Note 7708: *BR: 260.9 ±3.5 (stat) ±5.8 (sys)
±15.4 (lum)
Dilepton Invariant mass
#
events
Z to (CMUP)
Oops! Get different trigger efficiencies and MC/Data reconstruction factors
Higgs to WW UpdateCrossections for Z > all combinations
200
220
240
260
280
300
320
Dilepton Type
*B
R
Only statistical errors quoted, queries as to the SF correlation
Higgs to WW UpdateZ > ee, weights
Dilepton Scale Factor error Dilepton trigger efficiency error total weight error
CMUP weights 0.7635 0.0139 0.9915 0.0188 0.7571 0.0347
TCE weights 0.9920 0.0064 0.9987(avg) 0.0077(avg) 0.9907(avg) 0.00995(avg)
HepgZ number MC Z after selection (weighted) Acceptance (weighted) # event # back-ground
TCE 1.53E+06 110409.3416 0.0726263 6899 12
CMUP 1.27E+06 23118.9 0.0182097 1849 0
Higgs to WW UpdateZ Mass for MC all channels
Z M
ass
90.5
90.6
90.7
90.8
90.9
91
91.1
91.2
91.3
Dilepton Type
Higgs to WW UpdateZ Mass for all Data channels
Z M
ass
90.5
90.6
90.7
90.8
90.9
91
91.1
91.2
91.3
Dilepton Type
Higgs to WW UpdateZ > ee, calculation
Estimated using the number of same sign events
Corrects the Z for Z outside the mass window 66-166GeV
Corrects the luminosity due to the luminous region being greater than that over which the luminosity measurement is made
Acceptance is the number of MC events in the mass window after selection over the number of HepgZs in the mass window
For ATLAS
• Identify datasets and try to use Atlas General Ntuple – or fail! But create Dtuple
• Identify the “Rows” for ATLAS dilepton combinations (a few experts would do!)
• Measure Z cross section in Atlas: compute the same Trigger and reco efficiencies as in CDF. How far do we want to get involved in doing the actual studies?
• Go the extra two cuts to get the Z background – and all backgrounds, Higgs to WW.
• Put into an ATLAS Note
Additional Slides
Higgs to WW UpdateReproduction of Note 7708 Results
HWW analysis Event CutsIndex Event Selection cut
1 two leptons with pT l tr igger , non-tr igger >20, 10 GeV
2 Mll >16 Gev
3 nJ ets(ET > 15Gev) = 0 | | nJ ets (ET <55) = 1 | | nJ ets (ET < 40 ) = 2
4 missing ET > MH/ 4
5 MH> 150 | | (ET >50 GeV | | (missing ET , lep/ jet) >0.35
6 opposite lepton charge signs
7 M ll < MH/ 2 - 5GeV
8 ETl1 + ETl2 + missing ET < MH
Higgs to WW UpdateData Access Reorganisation
–Dtuple, an object based small Ntuple has been created for Analysis purposes–The Hww Selection code has been
modified to run from bothTopNtuple and StNtuple
–Correct matching up of StNtuple variables to TopNtuple
variables to be confirmed, along with Validation
Higgs to WW UpdateData Access Reorganisation
–Dtuple, an object based small Ntuple has been created for Analysis purposes–The Hww Selection code has been
modified to run from bothTopNtuple and StNtuple
–Correct matching up of StNtuple variables to TopNtuple
variables to be confirmed, along with Validation
Higgs to WW UpdateZ to ee (tight, central)
Cuts are the same as in ID efficiency Note 7309
Cut Condition
# lepton ==2
EM ET > 20 GeV
EHAD/ EEM < 0.055 + 0.00045 E
L shr < 0.2
Track PT >10 GeV/ c (if EM ET <=100 GeV)
>50/ c GeV (if EM ET > 100 GeV)
E/ p < 2 (if EM ET <=100 GeV)
q. x [-3.0,1.5]cm
| z| < 3cm
2< 10
track | z0| < 60 cm
Track Quality 3 axial and 2 stereo SL
with at least 5 hits out of 12 in each SL
Isolation < 0.1
Fiducial fidele =1 (Ces | X| <21 cm, 9< Ces | Z| <230cm)
(tower 9 excluded, most of tower next to chimney included)
no cosmic or conversion events
Higgs to WW UpdateZ to ll Crossection*BR measurement
–In the channels•Z > two tight central electrons•Z > two CMUP muons
–Both crosschecked using the old Mtuples and new Dtuples created from the original TopNtuples–Gen 5.3.3 zewk6d and zewk6m MC
datasets used–Good run lists 0031(378pb-1) for muon and 1001(374pb-1) for electron data
Higgs to WW UpdateZ to (CMUP)
Cuts are the same as in ID efficiency Notes 3767 and 7956 (JP) apart from the tight cuts are for 3 stereo hits.
Cut Condition
# lepton ==2
Track PT > 20 GeV
track | z0| < 60 cm
EEM <2+Max(0,0.0115(P-100)) GeV
EHAD <6+Max(0,0.028(P-100)) GeV
track | d0| < 0.2cm (if no silicon hits)
< 0.02cm (if silicon hits)
Isol < 0.1
| xCMU | < 3.0 cm
| xCMP | < 5.0cm
Track Quality 3 axial and 2 stereo SL
with at least 5 hits out of 12 in each SL
x-fid(CMP) < 0 cm
z-fid(CMP) < -3 cm
no bluebeam for runs <154449
no cosmic or conversion events
Higgs to WW UpdateOngoing work
–The Joint Physics efficiency Classes have been integrated into the
code in readiness for transition to Gen 6 –Ongoing investigations into finding
better discriminating variables for the HWW event selection–formation of good run lists for 6.1.2
data–Measurement of WW crossection
Higgs to WW UpdateImmediate Goals
–StNtuple Validation & migration–Dtuple Validation & migration–Incorporation of all exisiting data
•Z crossection measurement with new data•WW crossection measurement with new data•Monte Carlo comparison of acceptances for
H>WW using the JP weights•Fake study for 50 GeV jets
–Study the effects of high luminosity on all above
Higgs to WW Update
Future Goals
–Neural Net Analysis
–Vector Boson Fusion Analysis
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