Search for BSM at LHC Fayet Fest Paris

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Search for BSM at LHC Fayet Fest Paris November 9, 2016 Dirk Zerwas LAL

Search for BSM at LHC Fayet Fest Paris November 9, 2016 Dirk Zerwas LAL Orsay • • Introduction (kind of) Supersymmetry Not supersymmetry Conclusions

Pierre Fayet 1997: • GDR Supersymmetry: theorists and experimentalists (interdisciplinarity in France) • history

Pierre Fayet 1997: • GDR Supersymmetry: theorists and experimentalists (interdisciplinarity in France) • history of the prediction of the top quark mass 2009: • GDR Terascale 2017: • GDR-I Terascale The Susy-believersion of BSM at the LHC….

The LHC 2016: Proton-proton 13 Te. V 40 fb-1 Order of (2030): 3000 fb-1

The LHC 2016: Proton-proton 13 Te. V 40 fb-1 Order of (2030): 3000 fb-1 with 200 pileup events

Supersymmetry • • fermion boson has “no” problems with radiative corrections (quadrat. div. )

Supersymmetry • • fermion boson has “no” problems with radiative corrections (quadrat. div. ) has a light Higgs Boson (<140 Ge. V) interesting pheno at the Te. V scale spin-0 squarks: q R, q L ~ ~ sleptons: ℓ , ℓ ~R ~L h, H, A H± spin-1/2 spin-1 q gluino: g ~ ℓ g neutralino χi=1 -4 Z, γ charginos: χ±i=1 -2 W± Table from JFG who got it from Pierre! 3 (or more) neutral Higgs bosons: h, A, H 1 (or more) charged Higgs boson(s): H± and supersymmetric particles Many different models: • m. SUGRA, MSSM • Supersplit SUSY • GMSB • AMB Additional (s)particles: • NMSSM • MRSSM/N=1/N=2 hybrid • and many more R-parity • production of SUSY particles in pairs • (Cascade-) decays to the lightest SUSY particle • LSP stable, neutral and weakly interacting: neutralino (χ1) • experimental signature: missing ET First discovery: partner of the neutralinos (R=1) (see talk by Andreas)

The SM cross sections Cross sections measured over many orders of magnitude all in

The SM cross sections Cross sections measured over many orders of magnitude all in agreement with prediction …and as function of the CM energy

Search for Supersymmetry: gluinos and squarks Signature: • colored particles large (pb) cross sections

Search for Supersymmetry: gluinos and squarks Signature: • colored particles large (pb) cross sections • many high transverse momentum jets • large missing ET JFG yesterday Measure background from data (CRs)/ Extrapolate sensitive variable • many cross checks possible • no exciting deviations Gluino masses: 1. 7/1. 8 Te. V: still space left

Search for Supersymmetry: stops Direct stop pair production (right to left): • top +

Search for Supersymmetry: stops Direct stop pair production (right to left): • top + neutralino • Δ(m. Stop; χ) < mtop • Δ(m. Stop; χ) < mb + m. W (charm, 4 body) • Δ(m. Stop; χ) < 0 • different channels in the same figure as overlay: not a combination due to different assumptions

Search for Supersymmetry: Electroweak Sector Signature: • associated production of charginos and neutralinos •

Search for Supersymmetry: Electroweak Sector Signature: • associated production of charginos and neutralinos • supersymmetric version of WZ (difficult) • leptonic decays 3(and more) leptons (muons, e) • missing ET MSSM limits: • improve on LEP • • 1000 Ge. V (BF(ll)=0. 5) 350 Ge. V p. MSSM (M 1=5 Ge. V)

p. MSSM Vocabulary: • LEP: slepton to lepton + neutralino 1 defined as exclusive

p. MSSM Vocabulary: • LEP: slepton to lepton + neutralino 1 defined as exclusive signature • LHC: simplified model → BR=1 (even for cascade decays) p. MSSM limits: • Good coverage of p. MSSM • depence on LSP nature (via signatures)

Long lived sparticles Signature: • GMSB: stau as NLSP • Long lifetime • slepton

Long lived sparticles Signature: • GMSB: stau as NLSP • Long lifetime • slepton as heavy muon • • AMSB: chargino and LSP degenerate winos Decay to pion

RPV stops or scalar partners of gluinos Signature: • Pair produced resonances • Jet

RPV stops or scalar partners of gluinos Signature: • Pair produced resonances • Jet pairing combinatorics • Background (multi-jets) • no hint

7. 7 Te. V dijet

7. 7 Te. V dijet

Dijet and Di-electron resonances Di-jet/di-lepton searches: • Bump hunting • No bump observed •

Dijet and Di-electron resonances Di-jet/di-lepton searches: • Bump hunting • No bump observed • Can be applied to many different models • Depends on final stats q/g • Limits in the n-Te. V mass range

A di-photon hint? In SUSY could have been H

A di-photon hint? In SUSY could have been H

A WH hint? WH: • lnu bbar • bbar as single jet • MHW>1.

A WH hint? WH: • lnu bbar • bbar as single jet • MHW>1. 8 Te. V • 3 observed • 0. 3 expected • electron channel (not muon) A relief for SUSY

A WZ resonance hint? WZ: • boosted W, Z • Reconstructed as di-jets •

A WZ resonance hint? WZ: • boosted W, Z • Reconstructed as di-jets • Substructure (jet mass etc) • Side bands ATLAS-CONF-2016 -055 Would have been difficult for SUSY

Pierre Fayet convinced me LHC: • 5% level mass measurement HL-LHC: • improve to

Pierre Fayet convinced me LHC: • 5% level mass measurement HL-LHC: • improve to 1% ILC: • electroweak sector measurements • precision 0. 1% SFitter: Lafaye, Plehn, Rauch, D. Z. and friends Eur. Phys. J. C 54 (2008) 617 -644, Eur. Phys. J. C 71 (2011) 1520 LHC: • 12 fold ambiguity ILC: • solves ambiguities LHC: • hint on Parameter unification HL-LHC: • increases precision Dark matter (deduced): LHC: • % level with ambiguities Postpone all that fun a bit HL-LHC + ILC

Conclusions • Supersplit SUSY cross sections • Non-SUSY searches turned up empty • Room

Conclusions • Supersplit SUSY cross sections • Non-SUSY searches turned up empty • Room left for higher masses • Hope for new data…….