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BSM searches at LH(e)C and PDFs

Supersymmetry. BSM searches at LH(e)C and PDFs. Extra Dimension and RS resonances New gauge bosons (W’, Z’) and more. Monica D’Onofrio University of Liverpool. LHeC Workshop, Chavannes January 20 th 2014. Searching for new physics. Extra Dimensions.

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BSM searches at LH(e)C and PDFs

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  1. Supersymmetry BSM searches at LH(e)C and PDFs Extra Dimension and RS resonances New gaugebosons (W’, Z’) and more Monica D’Onofrio University of Liverpool LHeC Workshop, Chavannes January 20th 2014

  2. Searching for new physics Extra Dimensions Standard Model: remarkably successful description of known phenomena, butrequires new physics at the (multi)TeV scale. • Large, warped, or universal extra dimensions • Might provide: • Dark Matter candidate • Solution to Hierarchy problem • Unification of forces • Searches for new heavy particles, black holes.. Strong EW symmetry breaking • Modern variants of Technicolor • Might provide: • Dark Matter • Hierarchy problem • Possibly search for composite Higgs, new heavy vector bosons (Z’, W’…), 4th generation of quarks • Composite (SUSY) theories • Composite Higgsand top Supersymmetry • Introduce heavy superpartners, scalar particles, light neutral Higgs • More than100 parameters even in MSSM Monica D'Onofrio, LHeC Workshop 2014

  3. Outline Based on LHeC CDR and furtherstudies (100 fb-1 @ 1033instead of current 1034expected), current LHC results and mostrecent High Luminosity LHC studies Monica D'Onofrio, LHeC Workshop 2014 “ The LHC is the primary machine to search for physics beyond the SM at the TeV scale. The role of the LHeC is to complement and possibly resolve the observation of new phenomena…” LHeC CDR • New Physics searches investigatedfor LHeC • Contactinteractions, excitedleptons, Extra Dimension • Leptoquarks • R-parity conserving and R-parity violating SUSY Emphasis on complementarities with (High Lumi) LHC: • Implication of LHC findings for LHeC reach  up to date comparisons here • How LHeC can complement and resolveobservation of new phenomenaat the LHC • Implication of LHeC PDF constraints for the LHC

  4. Non-SUSY BSM models-contactinteractions- Lepto-Quarks- Extra-dimensions(more in back-up) Notmanychangeswrt last year.. In some casesitwould be good to update thesestudies Monica D'Onofrio, LHeC Workshop 2014

  5. NP in inclusive DIS at high Q2 Observedasmodification of the Q2 dependence all information in ds/dQ2 Alsoparametrizedasformfactors : Compositenessscale  LQ mass (>> √s) or ModifiedPlanck Scale in ED models Monica D'Onofrio, LHeC Workshop 2014 At these small scales new phenomena not directly detectable may become observable as deviations from the Standard Model predictions. A convenient tool: effective four-fermion contact interaction

  6. Quark substructure Radius ( distribution of EWK chargewithin q) reachbelow10-19 cm ATLAS and CMS constraints on 4-quarks CI (expected @ few 10’s TeV for 14 TeV LHC - notdirectlyrelated to EWK R) Monica D'Onofrio, LHeC Workshop 2014 Ifcontactterms originate from a model wherefermions are composite, scale proportional to composite objectradius

  7. Contactinteractions (eeqq) Similarto LHC ATLAS and CMS constraints on eeqq CI (expected up to 30-40 TeVatc.o.m. 14 TeV LHC) Monica D'Onofrio, LHeC Workshop 2014 New currents or heavybosonsmay produce indirecteffect via new particleexchangeinterfering with g/Z fields. Reach for L (CI eeqq): 25-45 TeV with 10 fb-1 of data depending on the model

  8. Leptoquarks (LQ) In narrow-widthapprox, production cross section ~ l Monica D'Onofrio, LHeC Workshop 2014 • By providingboth B and L in the initial state, the LHeCisideal to study the properties of new bosons with couplings to an e-q pair • Leptoquarks • Color-tripletbosons, couple to leptons and baryons of same generation • Can be scalar or vector • Massesat GUT scale, in various GUT theoriesas E6, some extended TC modelsalsopredict LQ atTeV-scale • Also squarks in RPV SUSY (seelater)

  9. LQ production at LHC ad LHeC Monica D'Onofrio, LHeC Workshop 2014 • At LHC, mostlypair production (from gg or qq) • iflnottoo strong (0.3 or lower), cross sectionindependent on l • Exclude up to 900 GeV for 1° generation • Expect to exclude up to 1.2 (1.5) TeVat 14 TeV 300 fb-1 for scalar (vector)-LQ

  10. LQ production at LHC and LHeC 0.1 Monica D'Onofrio, LHeC Workshop 2014 • At LHeC, single particle production • Probe LQ up to TeV scale

  11. CI at LHC and LHeC LHeC:signe from asymmetry of s/ssm in e+p and e-p data Ex: negative interferencetoo small to be disentagled Monica D'Onofrio, LHeC Workshop 2014 • LHC: Variation of DY cross section for CI model • CannotdeterminesimultaneouslyL and sign of interference of the new amplitudeswrt SM (e)

  12. High mass Drell-Yan for ED searches Both CMS and ATLAS searching for deviations in m(ll) tails CMS-PAS-EXO-12-027 CMS-PAS-EXO-12-031 Monica D'Onofrio, LHeC Workshop 2014 Non resonantsearches for ED (interference) sensitive to tails of DY distributionsthus to PDF For HL-LHC need to study in context with experimentaluncertainties (calibrations)

  13. SUSY searches- More and more stringentlimits on ‘classic’ scenarios- need to study impact of e-p in light of experimental and theoretical progress a fewreportedhereasinitial stage, otherstestedbutturned out to be notrelevant Monica D'Onofrio, LHeC Workshop 2014

  14. RPC scenarios for LHeC: sele-squark Re-cast feasibility and relevance in terms of whatweknow NOW Validonly for mSUGRAscenarios Monica D'Onofrio, LHeC Workshop 2014 Selectron-squark pair production checked in the past:

  15. Non-degenerate 1st and 2nd generation squarks http://arxiv.org/abs/1212.3328 m LSP = 0 GeV Will depend on LHC boundaries on these scenarios might be hard considering the increasing trigger thresholds in MET and jet pT uR, cRmight be the lightest Monica D'Onofrio, LHeC Workshop 2014 Strong constraints on gluino (1.4 TeV) and squark masses (up to 1.6 TeV) under assumption of 1stand 2nd generation squarks degenerate Review of current constraints on usual assumption on mass degenerate of 1st and 2nd generation squarks:

  16. Currentconstraints on 1-squark type Even with HL-LHC, medium-compressedscenariosdifficult Monica D'Onofrio, LHeC Workshop 2014 MET+jetssearchesgivelessstringentlimits Monojetanalysisconstrainscompressedscenarios (low DM sq-neut): hereshown for stop1, butequivalent for allothersquarks

  17. E-p  selectronR+uRsquark • Constraints on squarks more stringent • Less for right-handedsleptons Note:oldevaluationbased on mSUGRAgaveabout 10 fbxsection (e-p) Monica D'Onofrio, LHeC Workshop 2014 • Consider medium-compressedscenarios • Caveats: • consideronly RH u_squark (and eR)  Generallylowxs-ection • Too compressedfinalstates are invisible(soft decayproducts) • Example: • squark mass = 350 GeV, selectron mass = 330 GeV • neutralino1 mass = 200 OR 250 GeV

  18. E-p  selectronR+uRsquark mNeut=200 GeV pT(jet) MET pT(ele) GeV GeV GeV mNeut=250 GeV Monica D'Onofrio, LHeC Workshop 2014 • Use Madgraph5 to test the process (1K eventsatpartonlevel) for 60 GeV-7 TeV • Overall, tiny cross sections from MG (1-5 fb), butcheck in progress on parameters • Right-handedpolarization of electron beamincrease cross section of a factor of 2 • M(Neut)=200 GeV: higherpT of objectsasexpected, s@200 GeV= 4 x s@250 GeV

  19. E-p  selectronR+uRsquark • Use Madgraph5 to test the process (1K events at parton level) for 60 GeV-7 TeV • Overall, tiny cross sections (few fb), but check in progress on parameters • Right-handed polarization of electron beam increase cross section of a factor of 2 • M(Neut)=200 GeV: higher pT of objects as expected, s@200 GeV= 4 x s@250 GeV mNeut=200 GeV pT(jet) MET pT(ele) GeV GeV GeV mNeut=250 GeV To do: better estimate of total cross sections and check Bino-Wino-Higgsinoadmixture for neutralino1 beforestarting a properanalysis Monica D'Onofrio, LHeC Workshop 2014

  20. EWK RPC-SUSY production 50 fbxsection for pure Wino-like N1 Promising for low N1, butpossibly large bkg from SM (ieZ,higgs production) Monica D'Onofrio, LHeC Workshop 2014 • Charginos (C) and Neutralinos (N) fundamental for SUSY • Expected to be light in mostscenarios (C1, N1, N2 in particular) • N1 isoften the LSP and one of the preferredDM candidate • One of the mostdifficultscenarios for the LHC: medium-compressed N1, C1, N2 (DM fewGeV) • Notvisible in directsearches, mono-photon and mono-jet searchespossiblynot sensitive because of systematicunceratinties VS tinyxsect. • VBF scenariosinvestigated for 14 TeV LHC

  21. EWK RPC-SUSY production Monica D'Onofrio, LHeC Workshop 2014 • Question: can anything be doneat the LHeC ? • Completelyunchartedterritory, foundnothing in the literature, butwant to checkwhetheritisreallyhopeless. • Very first look, usingMadgraph: • Example of diagram for C1C1. Production of N1N1 and C1N2 equivalent for almost degenerate masses • Couplingstrenghtsdepend on the Wino-Higgsinomixture (notyetscanned)

  22. EWK compressed Monica D'Onofrio, LHeC Workshop 2014 1000K partonlevel Relativelyemptyevent, with oneforward jet only and not so high pT,MET Eventsdifficult to select, considering the low cross section (1-2 fb for no polarization) Seemsnotpromising butwould be best to better investigate the cross sectionpredictions (Madgraphprobablynotreliable): tooimportant to be given up?

  23. More models/scenarios to be investigated Very soft BR can be up to 10% - relevancedepends on the precise measurements of otherhiggsdecay processes http://arxiv.org/abs/1308.2153 Monica D'Onofrio, LHeC Workshop 2014 In RPC SUSY, interestingmodelsmight be: • General GaugeMediated SUSY: • Gravitinos are LSP (very light) • Neutralinos are often the NLSP: • Can decay in g+Gravitino • Ifsquarks and gluinos are decoupled, EWK production is the only chance: • At the LHC investigatingit in gg+METfinalstates • Loosequicklysensitivityif N1 haslow mass • Alternative proposed by theorists: • Higgsdecay in Grav+Neut1, followed by N1  g + G • Compositness and SUSY • Light LSP and sbottomscenarios

  24. R-parity violating SUSY Squarks in RPV modelscould be an example of ‘Leptoquarks’ • R-parity = (-1)3(B-L)+2s(R = 1 for SM particles, -1 for MSSM partners) If not conserved (RPV) different terms, couplings constraint by proton decay DL =1, 9 l couplings, 27 l’ couplings Plethora of new couplings, only partially constraints (m/100 GeV) Various strong constraints from LHC on Lambda and Lambda’’ (from multilepton and multijetsearches) Monica D'Onofrio, LHeC Workshop 2014

  25. SUSY @ LHeC: RPV scenarios LQ-like Monica D'Onofrio, LHeC Workshop 2014 • For squark production: • l’ couplings relevant in e-p production • Decays: direct or via cascade • Current limits up to HERA mass-bound • Strong lepto-quark constraints from LHC to be taken into account if RPV~100% • Cascade decays (via RPC vertex) lead to more complex and under-constrained signatures • Reach up to 1 TeV with LHeC • Feasibility of these searches will depend on LHC findings (useful in case of evidence )

  26. Targeting RPV stop production (and decay) UNDER INVESTIGATION using RPVMSSM_UFO model in Madgraph Monica D'Onofrio, LHeC Workshop 2014 • Possibleresonant production of stop1 • Constraints from LQ must be considered. • Rate: Xsection(st-st) x (l’131)2 • @8 TeV: Equivalent to about 10 fb for l’131=0.3  could be constrainedgiven the 7 TeVreach of eqeqsearches • Stop coulddecay via RPC modes: • Severalloop-holes in currentlimits • Might be important in low stop mass case. I.e. • stop in top+LSP (monotopsignatureatLHeC) • Non-zero Lamda’’ couplings: stop in 2 jets

  27. LHC – LHeCinterplay for SUSY • If No deviations from the SM observed in 300/fb • Extension of sensitivity (mass & cross section reach) with 3000/fb • Deviations from the SM observed in 300/fb • Signal characterization with 3000/fb Monica D'Onofrio, LHeC Workshop 2014 • If no evidencefor SUSY isfound in Run II, sparticlesmightbecome out of reach for LHeC • Still, interplay in terms of PDF quiterelevant • Based on resultsshown for ES document and ATLAS PhaseIILoI • Strategy: • Considerthree benchmark kind of processes: strong production (squark-gluino), stop,chargino/neutralino production

  28. Strong production mSUGRAreferencepoint: m0=650, m1/2=975, xs 1.1E-05 nb Decay chain might be complex, including Z or Higgs Monica D'Onofrio, LHeC Workshop 2014 xsection ~ 2.5 pb for m = 1000 GeV, ~ 0.01 pb for m(squark, gluino) = 2 TeV clearly, high stats samples are needed.

  29. PDF for gluinos production Monica D'Onofrio, LHeC Workshop 2014 • Impact of improved PDF fits on theoretical predictions for SUSY process: • Example: gl-gl production (assuming m_gl = m_sq)

  30. Impact on discovery/exclusionreach Note: impact of PDF uncertainties on SM background alsonotnegligible However mitigated by usage of Control Regions and semi data-driven estimate Monica D'Onofrio, LHeC Workshop 2014 • Dependencyon discoverypotentialand exclusionlimitsat300 and 3000 /fb for 14 TeVc.o.m. at the LHC ATLAS-PUB-2012-001 (MSTW2008 usedasnominal)

  31. Summary and outlook Need to (re-)estabilish a BSM working team to systematicallyreview the currentresults and study in detail the many more optionsavialable and exploreperhapsunchartedterritories ! Monica D'Onofrio, LHeC Workshop 2014 • LHeC provides complementarities to the LHC SUSY search program in the twenties • Ideal to search and studyproperties of new bosons with couplings to electron-quark • Direct searches for CI, excitedfermions, leptoquark, RPV SUSY, RPC SUSY in specificscenariosestabilished • More studies are needed to improve the BSM physics case  currentlyvery short person-power! • Interplay with HL-LHC to constraints on PDF crucial for model testing in case of observed deviations  an independent precision measurement of PDFs will be important for an efficient use of the high luminosity for setting reliable high mass limits

  32. Back-up

  33. PDF for LHC Monica D'Onofrio, LHeC Workshop 2014 Use precisionDrell-Yan (W,Z) data to constraintPDFs

  34. Otherproperties of LQs Monica D'Onofrio, LHeC Workshop 2014 • Spin: • LHC: LQ-LQ leads to angulardistributionsdepending on g-LQ-LQ coupling • LHeC: cosq* distribution of LQ decayis sensitive to spin • BR to neutrinos (good S/B for n-q) • Couplingmeasurement, once spin and chargeisdetermined

  35. LQ isospin family Monica D'Onofrio, LHeC Workshop 2014 Classificationusedhere (BRW framework)

  36. Squark mass splitting (A. Weiler) Monica D'Onofrio, LHeC Workshop 2014 Large splitting is possible

  37. LHC: The Roadmap to 2030 LHC has still only delivered a small fraction of the effective parton-partonlumidiscovery physics programme just getting started! • Accelerator timescale driven by several aspects: • Radiation damage of LHC components • R&D and construction of LHC upgrades • Required schedule of detector upgrades • Long Shutdown (LS) periods to installupgrades • Possibility of an HE (High Energy ) LHC still under discussion Monica D'Onofrio, LHeC Workshop 2014 ESPP-Cracow meeting:

  38. Searches for SuperSymmetry • Very stringent constraints from LHC on strongly produced sparticles (1st, 2ndgeneration squarks, gluinos)  can be quite heavy (multi-TeV) • Direct production of 3rd generation squarks and weak gauginos is becoming accessible as the amount of integrated luminosity increases (low cross sections) • Determination of masses by measuring endpoints of visible mass distributions • Measurement of couplings and spin (via angular analysis) Monica D'Onofrio, LHeC Workshop 2014 • If No deviations from the SM observed in 300/fb • Extension of sensitivity (mass & cross section reach) with 3000/fb • Deviations from the SM observed in 300/fb • Signal characterization with 3000/fb

  39. Third generation • For 3000 fb-1 of lumi @ 14 TeV • @ 600 GeV: 720 x 103 events • @ 1 TeV: 24 x 103 events • Analysis < 1 % efficiency • Acceptance depends on the decay mode Monica D'Onofrio, LHeC Workshop 2014 • If sq/gl are not found < 3 TeV • Still the stop (and possibly sbottom) are among the most important SUSY particles to be found! • At 14 TeV, stop cross section ~ 10-20 x xsect @ 7 TeV

  40. Stop analyses • An increase of integrated luminosity from 300 fb-1 to 3000 fb-1 improves the sensitivity to sq/gl by approximately 200 GeV • Can do more adding shape discriminants and / or boosted top reconstruction • For stop  t+LSP: 1-lepton + MET + jets • For stop b+chargino(C1 into W+N1): 2-lepton (+MET,jets) • Discriminant: MET, MT2 Monica D'Onofrio, LHeC Workshop 2014

  41. Weak Production Monica D'Onofrio, LHeC Workshop 2014 • As for light stop, light gauginoswellmotivated by naturalness • Rare process • @ 500 GeVchargino / neut 2 mass, expect ~ 6 x 104 events for 3 ab-1 • Direct access to weak gauginos • Mass hierarchy via kinematic edge studies (potential model dependent fit), couplings • Search in the ‘classical’ three-lepton and ETmiss final state originating from the decay of c1± and c20 as W+c10 and Z+c10 respectively • arxiv.org/abs/1207.4846 by H. Baer addressed c20  higgs+c10

  42. LQ properties Partondensityu,d >> ubar,dbar s(F=0) larger in e+p, s(F=2) larger in e-p Monica D'Onofrio, LHeC Workshop 2014 • If LQ observedat LHC  At LHeC can measurefermionnumber, flavorstructure, chiralstructure (from polarization of beam) • Ex.: Fermionnumber:

  43. Excitedfermions At the LHC: Stringentlimits, whichonlyapply to the contactinteraction case Monica D'Onofrio, LHeC Workshop 2014 Can be produceddirectlyiftheir mass isbelow the compositness scale

  44. Excitedfermions Upperlimit @ 95% CL (area abovecurvesexcluded) f=f’=1 Exclusion f/L = 1/M*  1.2 (1.5) TeV for √s 1.4(1.9) TeV Monica D'Onofrio, LHeC Workshop 2014 For gaugeinteraction, LHeC cross sectionmuchhigher Verygoodsensitivity

  45. HL-LHC: DileptonResonances  Sensitivity up to about 8 TeV Monica D'Onofrio, LHeC Workshop 2014 • Dielectron and dimuonchannelsexplored for 14 TeV and Phase I (II) luminosity: • Example from dielectronselection:

  46. Importance of PDF Monica D'Onofrio, LHeC Workshop 2014 If we see deviations from SM, will be important to characterize the physics underneath.

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