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Natural SUSY on Trial: Status of Higgsino Searches at ATLAS

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Natural SUSY on Trial: Status of Higgsino Searches at ATLAS Natural SUSY On Trial: Status of Higgsino Searches at ATLAS Julia Gonski Harvard University 25 October 2018 US LHC User’s Association Annual Meeting SUSY (The Defendant) • Provides unification of forces, dark matter candidate, and solution to hierarchy problem • Higgs mass quadratic corrections cancelled by new supersymmetric partners; higgsinos, stops and gluinos especially influential ➡ What do we search for first? 25 October 2018 J. Gonski !2 SUSY Mass Spectrum (if we got to pick) • Naturalness = reduce fine ˜ Li, e˜i L˜i, e˜i tuning ⟹ 10% B˜ B˜ ˜ ˜ Q˜1,2, u˜1,2, d˜1,2 Q1,2, u˜1,2, d1,2 W˜ W˜ mass ˜bR ˜bR g˜ g˜ • Dark matter candidate! Dominantly (but not purely) t˜ t˜R ˜ ˜ L higgsino tL tR ˜bL ˜bL H˜ • Lightest three˜ higgsinos are compressedH (Δm ~ few GeV) natural SUSY decoupled SUSY natural SUSY decoupled SUSY 25 October 2018 J. Gonski !3 FIG. 1: Natural electroweak symmetry breaking constrains the superpartners on the left to be light. Meanwhile, the superpartners on the right can be heavy, M 1 TeV, without spoiling FIG. 1: Natural electroweak symmetry breaking constrains the superpartners on the left to be naturalness. In this paper, we focus on determining how the LHC data constrains the masses of light. Meanwhile, the superpartners on the right can be heavy, M 1 TeV, without spoiling the superpartners on the left. naturalness. In this paper, we focus on determining how the LHC data constrains the masses of the superpartners on the left. the main points, necessary for the discussions of the following sections. In doing so, we will try to keep the discussion as general as possible, without committing to the specific Higgs the main points, necessary for the discussionspotential of of the the MSSM. following We sections. do specialize In doing the discussion so, we will to 4D theories because some aspects try to keep the discussion as general asof fine possible, tuning without can be modified committing in higher to the dimensional specific Higgssetups. potential of the MSSM. We do specializeIn the a naturaldiscussion theory to of4D EWSB theories the because various contributions some aspects to the quadratic terms of the Higgs potential should be comparable in size and of the order of the electroweak scale v 246 GeV. of fine tuning can be modified in higher dimensional setups. ⇠ The relevant terms are actually those determining the curvature of the potential in the In a natural theory of EWSB the various contributions to the quadratic terms of the Higgs direction of the Higgs vacuum expectation value. Therefore the discussion of naturalness potential should be comparable in size and of the order of the electroweak scale v 246 GeV. ⇠ The relevant terms are actually those determining the curvature of the potential in the direction of the Higgs vacuum expectation value. Therefore the discussion of7 naturalness 7 3 Example(EWKino(Spectrum 3 In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed Example(EWKino(Spectrum 3 3 Example(EWKino(Spectrum Example(EWKino(Spectrum In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed 3 ~ 0 ~ 0 ~ ± ~ In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed !3 !4 !2 3 3 H)(higgsino) In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed3 Example(EWKino(SpectrumExample(EWKino(SpectrumExample(EWKino(SpectrumSUSY Mass Spectrum Δm%~%few%–%tens%of%GeV ~Example(EWKino(Spectrum0 ~ 0 ~ ± ~ !3 !4 !2 ~ 0 ~ 0 ~ ± ~ (if we3H) got(higgsino to) pick)3 4 2 In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowedIn(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed30 October 2017 J. Gonski ! ! !12 ~ 0 ~ ± (higgsino) ~ 3 Δm%~%few%–%tens%of%GeV 3 2 H)1 Example(EWKino(SpectrumIn(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed~ 0 ~!0 ~!± ~W)(wino) 3Δm%~%few%–%tens%of%GeV4 2 Example(EWKino(Spectrum ~ 0 ~ ± In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed~ ! ! ! (higgsino) • 2 1 (wino) ˜ Δm%~%few%hundreds%MeV%H) ~Example(EWKino(Spectrum0 ~ 0 ~ ± Naturalness~ ~!0 ~!0 ~ ±= reduceW)~ fine Li, e˜i ˜ 3 In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed4 2 A Natural3 4 2 Electroweak Spectrum Li, e˜i ! ! ! 3H)(higgsino! !) ! Δm%~%few%hundreds%MeV%H)(higgsino) Δm%~%few%–%tens%of%GeV(assuming%heavy%sfermions%and%higgsinos) In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed30 October 2017 tuningJ. Gonski 10% 12 ~ 0 ~˜± ~ ˜ Δm%~%few%–%tens%of%GeV⟹ (assuming%heavy%sfermions%and%higgsinos)Δm%~%few%–%tens%of%GeV 2 B1 B Example(EWKino(Spectrum Gauginos ~ 0 ~ ! 0 ~ !Mass± Eigenstates˜~W) (˜wino) ˜ ˜ In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowed⇢3 4 2 ~ Q~1,2, u˜1,2,~d1,2 ~~ Q1,2, u˜1,2, d1,2 ~ 0 ~ ± ~ ~~0 ~0 ±0~ 0 ~ ± ~ ~ ~ ! ! ~!0 ~˜ 0 ~Δ±m%~%few%hundreds%MeV%0 ± (~higgsino0 ) ˜ !2 !1 W)(wino) !!2 3!1!4 !2 B)W)(bino(H))wino(higgsino) ) !3 !W4 !2 !2 !H)1 !1 (higgsinoW)W)(bino(wino) ) In(principle,(any(bino/wino/higgsino(mass(hierarchy(is(allowedA Natural~ 0 ~ 0 ~ ± Electroweak~ Spectrum H) B) !3 !4 !2 Δm%~%few%hundreds%MeV%H)(higgsino) Δm%~%few%hundreds%MeV%Δm%~%few%–%tens%of%GeV ~ Δm%~%few%–%tens%of%GeV(assuming%heavy%sfermions%and%higgsinos)mass (gravitino) Δm%~%few%–%tens%of%GeVΔm%~%few%hundreds%MeV% (assuming%heavy%sfermions%and%higgsinos)Δm%~%few%–%tens%of%GeV (assuming%heavy%sfermions%and%higgsinos) G) ˜ ~ Gauginos Mass Eigenstates ˜ bR ~ 0 ~ ± ~ Appears%in%GMSB/GGM%Li, e˜i ˜b (assuming%heavy%sfermions%and%higgsinos)˜ G)(gravitino) !2 !⇢1 W)(wino) ~ R Li, e˜i ~ 0 ~ ~ ~ ~ ~ ~~0 ~0 ±0~ 0 ~ ± ~ ~ ~ 1 ~ 0 ~ 0 ~ ± 0 ± ~˜ 0 models,%mass%~keV !!2 3!1!4 !2 B)W)(bino(H))wino(higgsino) ! ) Δm%~%few%hundreds%MeV%B)!(3bino!) 4 !2 !2 !1 ~!B10 ~ ± (higgsinoW))(bino(wino~) ) B˜ Appears%in%GMSB/GGM% Mass 2 H)1 ˜ B)˜ (wino) ˜ ˜ (assuming%heavy%sfermions%and%higgsinos)! !~ Q1,2, u˜1~,2, d01,2 W) ~ Q1,2, u˜1,2, d1,2 Δm%~%few%hundreds%MeV%Δm%~%few%–%tens%of%GeV ~ ˜ Δm%~%few%hundreds%MeV%(gravitino) 1 g˜ ˜ models,%mass%~keV (assuming%heavy%sfermions%and%higgsinos) G)(gravitinog˜ ) Δm%~%few%–%tens%of%GeVW G) Δm%~%few%hundreds%MeV%! WB)(bino) ~ ~ 0 ~ ˜ Appears%in%GMSB/GGM% ~ 0 ~ ± ~ !1 (binoAppears%in%GMSB/GGM%) Li, e˜i (assuming%heavy%sfermions%and%higgsinos)˜ Mass G)(gravitino) 2 1 (wino) B) • Li, e˜i xsec ! ! Dark matter candidate! (assuming%heavy%sfermions%and%higgsinos)mass ~ ~ 0 ~ W) models,%mass%~keV ˜ 1 ˜ models,%mass%~keV ~ ˜b bR ! Δm%~%few%hundreds%MeV%B)(bino) Mass~B0 ~ ± B˜ ~ R Appears%in%GMSB/GGM% G)(gravitino) Mass 2 1 Dominantly˜ ˜ (but(wino notG)) purely(gravitino˜ )) ˜ t˜L t˜R (assuming%heavy%sfermions%and%higgsinos)! !~ Q1,2, u˜1~,2, d01,2 W) ~ Q1,2, u˜1,2, d1,2 ˜ (gravitino) 1 ˜~Appears%in%GMSB/GGM%0 ˜ ˜ ~ models,%mass%~keVAppears%in%GMSB/GGM% W G) higgsinoΔm%~%few%hundreds%MeV%! !tL1 WB)t(Rbino) (g˜bino) ˜bL ~ 0 ~ g˜ models,%mass%~keVB) !1 (bino) Appears%in%GMSB/GGM% ˜ Mass models,%mass%~keV B) Mass xsec (assuming%heavy%sfermions%and%higgsinos)mass bL ~ models,%mass%~keV ˜ ˜b ~ ~ bR RMass ˜ (gravitino) Mass (gravitino) ˜ ˜ H G) G)(gravitinoweak scale) G) • Lightest three higgsinos aretL tR ~Appears%in%GMSB/GGM%0 ~ t˜L t˜R ˜ ˜ Appears%in%GMSB/GGM% 1 g˜ H bL Appears%in%GMSB/GGM% ! models,%mass%~keVB)(binocompressed˜) (Δm ~ few GeV) (< 400 GeV) g˜ bL models,%mass%~keVmodels,%mass%~keV Mass H˜ ~ natural SUSY decoupled SUSY Mass˜ Mass G)(gravitino) t˜L H t˜R t˜ t˜R natural SUSY decoupled SUSY L 25˜bL October 2018 Appears%in%GMSB/GGM%J. Gonski !4 ˜ natural SUSY decoupled SUSY bL models,%mass%~keV natural˜ SUSY decoupled SUSY Mass H H˜ FIG. 1: Natural electroweak symmetry breaking constrains the superpartners on the left to be light. Meanwhile, the superpartners on the right can be heavy, M 1 TeV, without spoiling FIG.natural 1: Natural SUSY electroweakFIG. symmetry 1: Naturaldecoupled electroweak breaking SUSY symmetry constrains breaking the constrains superpartners the superpartners on the on left the left to to be be light. Meanwhile, thenaturalness. superpartners In on this the paper, right can we be focus heavy, onM determining1 TeV, without how spoiling the LHC data constrains the masses of natural SUSY FIG. 1: Naturaldecoupled electroweak SUSY symmetry breaking constrains the superpartners on the left to be light. Meanwhile, the superpartnersnaturalness. In on this the paper, right we focus can on be determining heavy, howM the LHC1 TeV, data constrains without the spoiling masses of light. Meanwhile, the superpartners on the right can bethe heavy, superpartnersM 1 TeV, on without the left. spoiling the superpartners on the left. FIG. 1: Naturalnaturalness. electroweak symmetry In this paper, breaking we constrains focus the on superpartners determining on how the left the to LHCbe data constrains the masses of naturalness. In this paper, we focus on determining how the LHC data constrains the masses of light. Meanwhile,the superpartners the superpartners on on the right left. can be heavy, M 1 TeV, without spoiling FIG. 1: Natural electroweak symmetry breakingthe superpartners constrains the on the superpartners left. on the left to be the main points, necessary for the discussions of the following sections. In doing so, we will naturalness. In this paper, we focus on determiningthe main how points, the LHC necessary data constrains for the discussionsthe masses of of the following sections. In doing so, we will light. Meanwhile, the superpartners on the right can be heavy, M 1 TeV, without spoiling the superpartners on the left. try to keep the discussiontry to keep as general the discussionas possible, without as general committing as possible, to the specific without Higgs committing to the specific Higgs naturalness.
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