Report Primo Anno. Riccardo Manzoni Dottorato XVII ciclo - A. A

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1 1 Report Primo Anno Riccardo Manzoni Dottorato XVII ciclo - A. A

2 2 Overview Analysis: search for SM H τhτh in CMS Service Task in CMS: development of offline Tau DQM Conference: IFAE 2012, Ferrara School: HCPSS 2012, Fermilab - Cern

3 H τhτh 3

4 4 H τhτh Motivations H ττ has sizable BR (~%) at low mh H ττ is a probe for couplings to fermions possible insight on July 4 th boson s spin (if s = 2 H ττ forbidden) Higgs BR + Total Uncert cc bb gg Z WW [GeV] ZZ M H LHC HIGGS XS WG 2011

5 4 H τhτh Motivations H ττ has sizable BR (~%) at low mh H ττ is a probe for couplings to fermions possible insight on July 4 th boson s spin (if s = 2 H ττ forbidden) Higgs BR + Total Uncert cc bb gg Z WW [GeV] ZZ M H LHC HIGGS XS WG 2011 BR(τ h) = 65% two υτ in the final state missing energy broad mass peak just two υτ better mass resolution than semi/full leptonic channels complementary to well established τμτh, τeτh, τeτμ,τμτμ analysis

6 5 H τhτh in a nutshell Very Challenging large backgrounds from QCD and W/Z +Jets neutrinos MET no straightforward invariant mass reconstruction at very low mass (~ 0 GeV) Z ττ overwhelms the Higgs Need to be smart data driven techniques to infere shape and normalization SVFit algorithm: exploits info on secondary vertex to reco the di-τ invariant mass

7 H τhτh in a nutshell Very Challenging large backgrounds from QCD and W/Z +Jets neutrinos MET no straightforward invariant mass reconstruction Need to be smart data driven techniques to infere shape and normalization SVFit algorithm: exploits info on secondary vertex to reco the di-τ invariant mass at very low mass (~ 0 GeV) Z ττ overwhelms the Higgs nd muons τ object in CMS Particle Flow Tau: Hadron Plus Strip Decay Modes τ ID 1 prong (charged hadron) 1 prong + 1/2 strip(s) (neutral hadron) 3 prongs decaymode Isolation discriminators Lepton Rejection discriminator (e/μ) 5

8 AK5 algorithm and full energy corrections have been applied. The thresh turn-on curve for the additional jet is shown in Fig. 2. tau leg during the data-taking used for this analysis. Turn-on curves Trigger & Selections Baseline Selection trigger: 2 τ(pt>30) 1 Jet (pt>30) τ kin: pt > 40 GeV, η < 2.1 τ iso: both Medium MVA opposite charge antimu: loose for both τ s antiel: τ1 loose, τ2 tight leading jet pt > 50 GeV, η < 3 trigger matching (data only) L1+L2+L2.5+L3 Efficiency Data Analyzed Data (no suitable trigger in 2011) 196 Lumi ~ 5.1 fb After this step the Level-3 selections, applying cuts on reconstructed P the lepton+tau triggers. The thresholds have been changed from 25 Ge been obtained and applied to the associated periods. The differences bet 30 GeV turn-on curves are small, as the inefficiencies are dominated by t trigger, namely Level-1 and Level-2, which have not been changed. At L on the p T of the leading track of 5 GeV is applied on each tau to further The combination of L1+HLT efficiencies obtained from different running Fig. 3. Plots are shown for 30 GeV thresholds only. τ trigger efficiency (per τ) PFTau E T L2 Efficiency jet trigger efficiency PFJet p T Figure 2: Extra jet turn on curve. The full trigger turn-on curve (Fig. 3 right plot) is the one used for the analy with a 3 parameters function which represent the effective turn-on point, and the slope of the turn-on. This parameterization is then applied to the to reproduce the trigger efficiency as a function of the tau leg p T. The tu for the 30 GeV version of the trigger, obtained from 2012A and 2012B run found in Tab. 7. The uncertainty on this method has been estimated to 9% (per event, or take into account possible systematics due to this procedure. The impact rameterizations of the turn-on curve, as well as changing the fit range, ha left plot shows the impact of a energy scale shift by 3% on the tau turn different fit ranges, the plateau varies up to 3%, shown in Fig. 4 right p turn-on parametrizations, as well as the chosen parametrization with dif ues according to these variations, have been applied to the analysis and

9 7 Strategy: divide et impera PRODUCTION MODES g g t t g t g H BOOSTED the Higgs system acquires momentum recoil against high pt jet H+jet(s) production favorited against Z+jet(s) production better mass resolution, Z/H separation q q W W q q H VECTOR BOSON FUSION very peculiar experimental signature low backgrounds two energetic jets with high mjj and high Δη separation testing the Higgs coupling to W/Z, which is the coupling the mechanism lives on

10 7 Strategy: divide et impera PRODUCTION MODES g g t t g t g H (pp H+X) [pb] 2 1 pp H (NNLO+NNLL QCD + NLO EW) pp qqh (NNLO QCD + NLO EW) s= 8 TeV LHC HIGGS XS WG 2012 q q W -1 pp WH (NNLO QCD + NLO EW) pp ZH (NNLO QCD +NLO EW) pp tth (NLO QCD) q W q H M H [GeV]

11 7 Strategy: divide et impera PRODUCTION MODES g g t t g t BOOSTED not(vbf) g H q q W W q q H VBF jet2 pt > 30 GeV Δη(j1,j2) > 2.5 mjj > 250 GeV central Jet Veto

12 8 Background Estimation Z!! ttbar di-bosons QCD norm: CMS meas. shape: emb. 5.1 fb -1 norm: CMS meas. shape: MC norm: CMS meas. shape: MC next slide Boosted: W+ jets VBF: W+ 3jets norm: control region and scale factor data/mc (from "! channel) shape: MC in control region (! 1 iso,! 2 relaxed iso RawMVA>0.6)

13 9 QCD Estimation QCD bkg given by jets badly reco ed as τ (Fakes) most difficult bkg to deal with completely Data Driven estimation (ABCD method) systematics related to this method have been carefully investigated Signal Region cuts as above Tight Iso SS cuts as above, but SS Loose Iso OS one of the two τ s iso relaxed Loose Iso SS one of the two τ s iso relaxed and SS

14 9 QCD Estimation QCD bkg given by jets badly reco ed as τ (Fakes) most difficult bkg to deal with completely Data Driven estimation (ABCD method) systematics related to this method have been carefully investigated QCD: shape from cuts as above scale from / Signal Region Tight QCD Tight Iso Iso SS cuts as Yield above, but Bkg subtracted SS (MC) Loose Iso OS QCD shape one Bkg of subtracted the two (MC) τ s iso relaxed Loose QCD Loose Iso Iso SS one of the Yield two τ s iso Bkg relaxed subtracted and (MC) SS

15 QCD Estimation in addition, since the kinematicks of the τ s in Loose Iso wrt to Tight Iso region, the ΔR(τ1,τ2) and # of Primary Vertices distributions have been checked in the following control regions τ pt > 40 GeV, no ΔRττ cut Tight Iso SS Loose Iso SS a weight, obtained by morphing the ΔR(τ1,τ2) and #PV distributions in to match the ones in, w(δr(τ1,τ2), #PV) has been applied, event by event in BOOSTED_QCDTightSS dr_ BOOSTED_QCDTightSS BARE_ drtt BOOSTED_QCDTightSS dr_ BOOSTED_QCDTightSS BARE_ nvert ΔR(τ1,τ2) and #PV are not correlated so w(δr(τ1,τ2), #PV) is safely w(δr(τ1,τ2))* w(#pv)

16 11 QCD Estimation: Shape Systematics obtained by varying the definition of the RW regions above varied ΔR(τ1,τ2), varied Isolation WP effect of different weights on the mass shape we took the envelope definition of two boundary shapes: shifted up/down also bin by bin statistical fluctuation has been considered as a shape definition of nbins (x2) shapes with one bin per shape fluctuating up/down from nominal value Nominal ± stat unc. Δ R < 2 Δ R < 3 τ iso < 0.4 τ iso < 0.6 QCD shape unc. 0 Estimated SS QCD shape Shape uncertainty Yield(+shape) uncertainty Stat(+yield+shape) uncertainty True SS QCD shape BOOSTED CLOSURE TEST 16 Estimated SS QCD shape Shape uncertainty Yield(+shape) uncertainty Stat(+yield+shape) uncertainty True SS QCD shape VBF CLOSURE TEST SHAPE ENVELOP svfitmass svfitmass svfitmass

17 Results PAS HIG , AN [1/GeV] dn/dm ττ τ h τ -1-1 CMS Preliminary CMS Preliminary s = 8 TeV, L = s5 = fb 8 TeV, L h= 5 fb 25 (5 ) H ττ m =125 (5 ) H ττ H observed observed Z ττ Z ττ 20 tt tt electroweak electroweak QCD QCD bkg. uncertainty bkg. uncertainty [1/GeV] dn/dm ττ 15 m =125 H τ h τh [1/GeV] dn/dm ττ 1.2 CMS Preliminary -1 s = 8 TeV, L = 5 fb τ h τh (5 ) H ττ m =125 H observed Z ττ tt electroweak QCD bkg. uncertainty BOOSTED 0.4 VBF m ττ [GeV] m ττ [GeV] [GeV] Figure 2: Observed and expected Higgs boson candidate mass spectra in the jt h t h (left) and jjt h t h (right) channels. The expected contribution from SM Higgs boson production with mass m H = 125 GeV is shown, scaled up by a factor of 5, by the dashed line. The background labeled electroweak combines contribution from W+jets, Z+jets and diboson processes. fits the data taking in input the nominal shapes of all the background ands Higgs 265 contributions 6 Systematic Uncertainties systematic errors are taken into account both for normalization and shape mismodeling 266 the The tool efficiencies returns the for 95% the CL Higgs exclusion boson signal limit and on Higgs some of σ the in background samples are estimated σsm units 267 using MC simulation. Where possible, these efficiencies are measured in control regions in 268 data, and residual differences between the efficiencies in the MC simulation and data are cor- 269 rected by scaling the simulation to match the efficiency measured in data. The uncertainties on Post Fit mass distributions usual CMS Higgs limit tool: 270 the simulation-to-data correction factors are 12 taken as systematic uncertainties, and are propa- 0.0 m ττ

18 12 Results PAS HIG , AN % CL limit on σ/σ SM 20 CMS -1 Preliminary, H τ h τ h, s = 8 TeV, L = 5.1 fb observed expected ± 1σ expected ± 2σ expected no evident H excess expected ~ 5 x σsm observed limit compatible with expected within 1σ observed ~ 4 x σsm m H [GeV]

19 Full H ττ Results References H τhτh H τhτh + W/ZH ττ full H ττ comb 95% CL limit on σ/σ SM 20 CMS -1 Preliminary, H τ h τ h, s = 8 TeV, L = 5.1 fb observed 18 expected ± 1σ expected 16 ± 2σ expected TO BE FURTHER DISCUSSED IN CMS, NOT PUBLIC YET m H [GeV] % CL limit on σ/σ SM CMS -1 Preliminary, VH+τ h τ h, s = 7-8 TeV, L=5-fb observed 9 expected ± 1σ expected 8 ± 2σ expected m H [GeV] H ττ, 5.0 CMS s = 7-8 TeV, L=5- -1 Preliminary, H τ τ, s = 7-8 TeV, L=fb observed Expected Limit 4.5 expected Combined -1 ± 1σ expected 4.0 τ h τ h (5 fb ) -1 ± 2σ expected ZH 2l2τ ( fb ) WH τ h +2l ( fb ) Figure 3: The expected and observed 95% CL upper limits on SM Higgs boson production in analyses presented in this document fb -1 using is shown other final at states. left. The contributions to the expected limit from the all-hadronic, ``t h, and ``LL subchannels are compared at right. 8 Summary 95% CL limit on σ/σ SM m H [GeV] Figure 4: Expected and observed 95% CL upper limits on SM Higgs boson production searches described in this Summary combined with previous CMS SM H! tt searche 5 fb -1 fb An extended search for standard model Higgs bosons decaying to tau pairs at the CMS experiment has been described. The search is conducted using events with three or four isolated leptons in fb 1 of 7 and 8 TeV CMS data, and with events with a pair of hadronic tau candi- 13 1

20 14 Perspectives time scale O(months) more data O(15 fb -1 ) soon reduce the QCD systematics get in sync with other H ττ analysis work for the MSSM analysis to get started also in double hadronic

21 Offline Tau DQM 15

22 16 DQM what? DQM Data Quality Monitor runs in synch with data taking (online) or at the end of each run (offline) monitors the quality of the data taking for subdetectors (pixel, tracker, ECal, HCal...) for physics objects (muons, electron, taus...) shifters work 24/7 to control the DQM plots and report problems to experts all the needed plots are gathered into a Graphic User Interface for the DQM developers the goals are: write efficient code to check sensitive information write instructions & documentation and follow the shifters

23 17

24 18 Tau DQM Overview monitor on the ParticleFlow Tau reco quality e τ and μ τ fake rate (check one-prong efficiency) light jet τ fake rate (aka QCD bkg in the analysis) Z τμτh efficiency is fairly new development got started in early 2012 is running offline (run by run) still in development, not yet in the official shifter s workflow

25 19 What we monitor think about a matrix: rows: different PFTauID discriminators WP to reject e faking τ: loose, medium & tight to reject μ faking τ: loose, medium & tight to reject jets faking τ: loose, medium & tight which Dataset? SingleElectron SingleMu SingleMu/Jets columns: basic quantities τ pt, η, ϕ, #PV ~ 30 plots to look at (may be reduced to ~, see next slide) µµ invariant mass distribution Tag&Probe using the Z ee/μμ, fitting slices of pt etc.... silky smooth Zμμ, a nightmare for Zee automatic interaction with the conddb to retrive the correct trigger path the missing one: Zττ yield

26 20 LOOSE ISOLATION DISCRIMINATOR jet τ vs. η jet τ vs. ϕ jet τ vs. of #PV jet τ vs. τ pt most of the core stuff is already here: Fake Rate vs. τ pt, #PV, η, ϕ we have corresponding plots for μ τ and e τ we want to monitor different Working Points for the TauID, it would be great to overlay them

27 21 Documentation first version of the shift TWiki not yet in the shifter s instruction summary page still to figure out how to simplify shifter s life by making the comparison with reference plots easier

28 Schools & Conferences 22

29 23 Search for H ττ in production processes in association with jets in CMS proceedings sottomessi, in pubblicazione su il Nuovo Cimento C

30 backup 24

31 25 Uncertainties Experimental Uncertainties Propagation into Limit Calculation Uncertainty Uncert. Boost VBF Tau ID (*) ±6% per t ±12% ±12% Trigger (*) ±4.5% per t ±9% ±9% JES (Norm.) (*) ±2.5 5% per jet 1 8% ±1 8% Norm. Z! tt ±4.5% ±11% Norm. t t (*) ±% ±30% Norm EWK ±30% ±30% Norm Fakes ±5.6% ±22% Lumi (Signal & EWK) ±4.5% ±4.5% Norm. W + jets ±30% ±30% Norm. Z: l fakes t h ±% ±% Norm. Z: jet fakes t h ±% ±% H shape unc. Theory Uncertainties (SM) Propagation into Limit Calculation Uncertainty Uncert. Boost VBF PDF (*) - ±2 8% ±2 8% µ r /µ f (gg! H) (*) - ±15% ±30% µ r /µ f (qq! H) (*) - ±4% ±% µ r /µ f (qq! VH) (*) - ±4% ±4% UE & PS (*) - 4% ±4% systematic shape uncertainties: τ energy scale for all but QCD (taken from data) data driven QCD estimation systematic