New Physics search at CMS

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1 New Physics search at CMS Mykhailo Dalchenko La Thuile-2017

2 Overview What is New Physics? Standard Model physics has standard problems: hierarchy, baryon asymmetry, gravity, etc... Exotica New resonances Long-lived particles Gravitons... SUperSYmmetry See Florent Lacroix s talk This talk Dark Matter See Bhawna Gomber s talk 2

3 Experimental signatures Neutral resonances Leptoquarks (3rd gen) dilepton with ` = e, µ Energetic lepton ( ` = e, µ ) plus ditau with hadronic and leptonic decays LQ! W(jj) diphoton dijet with light quarks jets Heavy stable particles dijet with heavy quarks jets Disappearing tracks Z+photon Displaced vertices Charged resonances lepton + MET with ` = e, µ And many more W 0! tb with different top quark decays 3

4 Outline CMS performed very well in the past years Huge amount of results were produced Recent Beyond Standard Model results amounts: 79 Exotica analyses 16 Beyond 2nd Generation analyses (relatively new group :)) Not possible to cover everything in 20mn talk! Concentrate on the most recent results 4

5 The CMS detector at the LHC 5

t pileup Jet Energy scale corrections derived from data Detailed studies of MET/MHT

6 Objects reconstruction Jets and MET: Good performance for both 25 and 50 ns bunch spacing and w.r.t pileup Jet Energy scale corrections derived from data Detailed studies of MET/MHT conducted Leptons and photons: New isolation algorithm, exploring dependency of isolation cone vs transverse momentum New and improved algorithms for leptons and photons identification 6

7 Exotica searches: brief summary 13 TeV 8 TeV LQ1(ej) x2 LQ1(ej)+LQ1(νj) β=0.5 LQ2(μj) x2 LQ2(μj)+LQ2(νj) β=0.5 LQ3(τb) x2 LQ3(νb) x2 LQ3(τt) x2 LQ3(vt) x2 Single LQ1 (λ=1) Single LQ2 (λ=1) RS1(jj), k=0.1 RS1(γγ), k=0.1 RS1(ee,μμ), k=0.1 SSM Z'(ττ) SSM Z'(jj) SSM Z'(ee)+Z'(µµ) SSM W'(jj) SSM W'(lv) RS Gravitons CMS Preliminary SSM Z'(bb) e* (M=Λ) μ* (M=Λ) q* (qg) q* (qγ) f=1 b* Leptoquarks Heavy Gauge Bosons Excited Fermions TeV TeV TeV TeV CMS Exotica Physics Group Summary ICHEP, 2016! coloron(jj) x2 coloron(4j) x2 gluino(3j) x2 gluino(jjb) x2 ADD (γ+met), ned=4, MD ADD (jj), ned=4, MS QBH, ned=6, MD=4 TeV NR BH, ned=6, MD=4 TeV String Scale (jj) QBH (jj), ned=4, MD=4 TeV ADD (j+met), ned=4, MD ADD (ee,μμ), ned=4, MS ADD (γγ), ned=4, MS Jet Extinction Scale dijets, Λ+ LL/RR dijets, Λ- LL/RR dimuons, Λ+ LLIM dimuons, Λ- LLIM dielectrons, Λ+ LLIM dielectrons, Λ- LLIM single e, Λ HnCM single μ, Λ HnCM inclusive jets, Λ+ inclusive jets, Λ- Multijet Resonances Large Extra Dimensions TeV TeV Compositeness TeV 7

8 Dilepton resonance search Selection: Two isolated opposite sign same flavor leptons Relatively high transverse momentum. In case of more than one pair reconstructed, select the highest pt pair Put constraints on R = (pp! Z0 (``)+X) (pp! Z(``)+X) CMS-PAS-EXO

Di-tau resonance search JHEP02(2017)048 Analysis is performed for various tau decays: Search for back-to-back tau pairs with missing energy aligned correspondingly For

9 Di-tau resonance search JHEP02(2017)048 Analysis is performed for various tau decays: Search for back-to-back tau pairs with missing energy aligned correspondingly For lepton-involved modes use single lepton trigger For fully hadronic decay require di-tau hadronic trigger Data driven background estimation technique was used wherever possible 9

10 Di-tau resonance search No evidence of NP decaying to tau pair is observed JHEP02(2017)048 10

11 Diphoton resonance search Selection: Two energetic (>75GeV) photons Examine spectrum above 500 GeV /j.physletb

12 Dijet resonance search CMS-EXO Selection: Dijet back-to-back topology High-mass search (PF jets):. Low-mass search (Calo jets): Spatially close jets are merged into wide jets to reduce analysis sensitivity to I(F)SR Dijet invariant mass spectrum can be described with following function: 12

13 Dijet resonance search CMS-EXO

14 Boosted topology: Z(qq) + photon CMS-PAS-EXO

15 Boosted topology: Z(qq) + photon CMS-PAS-EXO

16 W 0! ` + MET CMS-EXO

W 0! ` + MET : model-independent limit setting CMS-EXO-15-006 Perform a single bin cut-and-count cross-section measurement Such result doesn t depend on the resonance shape If the

17 W 0! ` + MET : model-independent limit setting CMS-EXO Perform a single bin cut-and-count cross-section measurement Such result doesn t depend on the resonance shape If the reconstruction efficiency is uniform (which is the case here for MT>500 GeV), then the limit on a model cross-section can be obtained in a following way: where is a model-dependent acceptance factor 17

18 3rd generation leptoquarks CMS-PAS-EXO

19 Beyond 2 Generations Vector-like quark pair production Resonances to heavy quarks Excited quarks Q qw T th 20 fb 35 fb Z (1.2%) tt Z (10%) tt 8 fb t* tg S=3/2 80 fb 15 fb t* tg S=1/2 500 fb 8 TeV T tz T bw B bh B bz B tw X5/3 tw 25 fb 7 fb 7 fb 35 fb 9 fb 4 fb 8 TeV 13 TeV gkk tt W tb W tb M!R Mν<MW < MW W tb M!R Mν>MW > MW Z (1%) tt 40 fb 40 fb 50 fb 50 fb 100 fb b* tw KL=1 70 fb b* tw KR=1 60 fb b* tw k=k=1 KL/KR=1 70 fb Observed limit 95%CL (TeV) X5/3 tw 300 fb Z (10%) tt 120 fb T bw 60 fb Z (30%) tt 200 fb t lep cwb=1.5 T th cwb)=1.5 t lep czt=2.5 T th czt=2.5 t had cwb=1.5 T th cwb=1.5 t had czt=2.5 T th czt= Observed limit 95%CL (TeV) Vector-like quark single production 800 fb 900 fb 600 fb 400 fb 13 TeV gkk tt W tb Z Tt tzt 400 fb 200 fb 150 fb 8 TeV 13 TeV Observed limit 95%CL (TeV) radion HH W WH Z ZH GBulk WW Gbulk GBulk Gbulk ZZ Resonances to dibosons 6 fb 10 fb 13 fb 20 fb 30 fb 8 TeV 13 TeV T tz cwb=1.5 T tz c(zt)=1.5 czt=1.5 B bz c(wt)=1.5 cwt=1.5 T bw c(wb)=1.5 cwb=1.5 cwb=1.0 Y th c(wb)= fb 200 fb 250 fb 200 fb 200 fb B2G new physics searches with heavy SM particles W VW HVT(B) W WH HVT(B) Z VH HVT(B) radion HH 28 fb 40 fb 18 fb 20 fb Observed limit 95%CL (TeV) Observed limit 95%CL (TeV) model-independent 19

20 Top quark-antiquark all hadronic resonances Selection: CMS-PAS-B2G Dijet back-to-back topology pt(jet) > 400 GeV Both jets should satisfy top-tagging criteria Veto events with leptons Jet reconstruction and top tagging: Anti-Kt algorithm with R=0.8 (AK8 jets) Recluster using CA algorithm Apply soft drop algorithm with angular exponent β = 0, soft threshold zcut < 0.1, and characteristic radius R0 = 0.8 Identify b quark using combined secondary vertex b-tagging algorithm Calculate the N-subjettines for the top quark: Apply the mass window 20

21 Top quark-antiquark all hadronic resonances CMS-PAS-B2G

22 Conclusions CMS performed very well in 2016 A complete set of various EXO analysis covering different topologies have been deployed by CMS Given the current amount of data most of them targeting mainly resonance production in frames of different EFT A good agreement between observation and prediction has been observed in all cases Stay tuned, new data will become public soon! 22

How, Then, Will We Find BSM Physics? Gustaaf Brooijmans

How, Then, Will We Find BSM Physics? Experimental Thoughts What s new? LHC 3 era has started Hard to say how much data in 25: 5 fb - ±?? But 26 should be rich Higgs exists, light Naturalness: Increased