Data results for inclusive all-hadronic (RAwith 318 nb-1
SUSY Hadronic/GMSB Meeting 27-08-10
[C. Rogan et al.]
Data Plots Towards Jamboree
Introduction and full analysis path + full MC analysis shown by Chris yesterday
http://indico.cern.ch/conferenceDisplay.py?confId=105112
AN- will appear very soon (possibly next week)
CMS DATA
Fully-Inclusive Hadronic SUSY Search [C.Rogan et. al.]
New variables to be used together for discovery and characterization of SUSY
Doesn’t involve MET Uses both transverse and
longitudinal information Peaks for signal events -
falls exponentially for backgrounds
Dimension-less - for S/B discrimination
Suppresses backgrounds and shapes distributions in the variable in a predictable and well-understood way - the Razor
SUSY LM1
Alpgen QCD
http://indico.cern.ch/conferenceDisplay.py?confId=93857http://indico.cern.ch/conferenceDisplay.py?confId=105112
http://indico.cern.ch/conferenceDisplay.py?confId=95896
http://arxiv.org/abs/1006.2727
N.B. Good Data/MC agreement w/ ALPGEN -
NOT w/ Pythia (see backup)
Analysis using these variables sensitive to SUSY LM1 with ~10 pb-1 of data for PF jet, Calo jet and/or Track jet analysis (JPT in progress)
PF Jets Track Jets Calo Jets
MR Peaks for signal events - falls
exponentially for backgrounds in all cases
(see also back-up)
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Exponential behavior
invariant under cleaning
procedure
Min-Bias data from June 16th ReReco
Variables robust against detector mis-measurements/noise/spurious effects
Data/MC comparisons in control regions towards background estimations (Loose R
cuts + different control regions = over-constrained bkg yields in signal region)
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Selection/Sample Details
For everything shown in this talk: 7 TeV MC (see back-up slide for list of samples) 7 TeV Data (up to run 140387 right now ~318 nb-1) OR of HT200 and Jet110 triggers (for the moment) PF MET used (tcMET or corrected caloMET fine too) Require di-jets satisfying (parallel analyses):
NO explicit lepton/photon reco or ID in constructing these variables If > 2 reco jets, form two hemispheres by minimizing invariant masses
added in quadrature (see back-up slides)
Corrected Calo jets Corrected PF jets Uncorrected Track jets
Loose jet ID Loose jet ID Only high quality tracks w/ vertex consistent
with reco PV considered for clustering
MR and R in Data (II)
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CMS DATAAlpgen QCD MC
Behavior of MR and R is confirmed with data both qualitatively and quantitatively
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Towards Backgrounds Estimations
Using a loose R-cuts we have a QCD dominated sample which we can use to measure the QCD slope, as a function of R-cut, in the low MR region
Can do this in any region with QCD population in low MR
QCD background control sample from data
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SUPER-PRELIMINARY Discovery Potential
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3 Observation 5 Discovery
Here, we look at estimated sensitivity for a PF Jets based search, doing a counting experiment and estimating systematic uncertainty assuming ratios of
events in control regions to signal region (conservative estimate)Sensitivity comparable for each jet type considered