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Split and Tev Scale Supersymmetry – Signals at the LHC – Signals at the ILC

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Split and Tev Scale Supersymmetry – Signals at the LHC – Signals at the ILC SPLIT SUPERSYMMETRY Tilman Plehn Max–Planck–Institut für Physik, Bayern – Split and TeV scale supersymmetry – Signals at the LHC – Signals at the ILC – What stays [W. Kilian, P. Richardson, TP, E. Schmidt: EPC C39] Tilman Plehn: Split Supersymmetry – p.1 TEV SCALE SUPERSYMMETRY: 1 Starting from data... – ...which seem to indicate a light Higgs – problem of light Higgs: scalar masses perturbatively unstable 2 2 2 quadratic divergences ±mh / g ¤ all–orders Higgs mass driven to cutoff mh ! ¤ ) solution: counter term for exact cancellation ) artificial, ugly, fine tuned ) or new physics at TeV scale: supersymmetry extra dimensions little Higgs (pseudo–Goldstone Higgs) Higgsless/composite Higgs YourFavoriteNewPhysics... ) all beautiful concepts and symmetries ) in general problematic to realize at TeV scale [data seriously in the way] Idea of supersymmetry: cancellation of divergences through statistics factor (-1) [scalars vs. SM fermions; fermions vs. SM gauge bosons; fermions vs. SM scalars] Tilman Plehn: Split Supersymmetry – p.2 TEV SCALE SUPERSYMMETRY: 2 Bright side – light fundamental Higgs by construction [data] – 3 running gauge couplings meet — GUT gauge group [data] – R parity — stable proton yields dark matter [data] – 2 Higgs doublets — radiative symmetry breaking [beauty] – local supersymmetry – including gravity? [beauty] – rich LHC phenomenology [effective theory of everything short–lived] spin d.o.f. Dark side gluon G¹ 1 n-2 ! gluino ~g 1/2 2 Majorana – unknown Susy breaking gauge bosons ; Z 1 2+3 ! masses, couplings, phases Higgs bosons ho; Ho; Ao 0 3 ! neutralinos Âo 1/2 4 ¢ 2 Majorana ~i – flavor physics and Susy breaking gauge bosons W§ 1 2 ¢ 3 Higgs bosons H§ 0 2 § ! CKM and lepton flavor? ! charginos  1/2 2 ¢ 4 Dirac ~i – 2 Higgs doublet model fermion fL; fR 1/2 1+1 ! sfermion ~fL;~fR 0 1+1 ! ¹ and Susy breaking? [Giudice, Masiero] ) as many exclusive analyses as possible [never believe us theorists when we say we know...] Tilman Plehn: Split Supersymmetry – p.3 TEV SCALE SUPERSYMMETRY: 3 Gauginos and higgsinos in the SUSY spectrum [Dimopoulos; Drees, Martin] » » – gauginos–higgsinos mixing: mÂ~0 m + or mÂ~0 m + in MSSM 2 Â~1 1 Â~1 m 0 m swc¯ m sws¯ ~B ¡ Z Z 0 m m cwc¯ mzcws¯ m p2m cws¯ 0 W~ Z ¡ 1 W~ Z mZswc¯ mZcwc¯ 0 ¹ à p2mZcwc¯ ¹ ! B ¡ ¡ C ¡ B m sws¯ m cws¯ ¹ 0 C B Z ¡ Z ¡ C @ A » – heavy gluinos through unification: m~B;W~;~g=m1=2 0:4; 0:8; 2:6 [mass and coupling unification independent] 0 – lightest Susy partner Â~1; º~ 0 ~ ~ ) after dark matter data Â~1 » B; W [Ellis, Falk, Olive...] Tilman Plehn: Split Supersymmetry – p.4 PHYSICS OF SPLIT SUPERSYMMETRY: 1 Split supersymmetry [Dimopoulos, Arkani-Hamed; Giudice, Romanino] – forget about fine tuning [Higgs will never be as bad as cosmological constant] – remember all the good things Susy did for you [dark matter, unification from data] – notice that scalars are evil [lepton and quark flavor, Higgs mass and LEP2] – remember simple facts about unification [SU(5) multiplets decouple; Dawson, Georgi 1979] ! ) make all scalars heavy [hope: m mGUT?] ) protect all gaugino and higgsinoe masses [ m ; m . TeV ] Â~i ~g Fine tuning no excuse for multi–billion dollar experiments [trigger by popular vote of theorists?] – gluinos and gauginos at the LHC – gauginos and higgsinos at the ILC ) is it supersymmetry? ) is it split? Tilman Plehn: Split Supersymmetry – p.5 PHYSICS OF SPLIT SUPERSYMMETRY: 2 Heavy scalars and the Higgs mass [Giudice, Romanino; Arvantaki, Davis, Graham, Wacker] » 4 2 2 – known leading corrections increased: mh mZ + GFyt log(m~t =mt ) ) large mh for heavy stops [out of LEP2 reach] ) not a precision observable anymore [large logarithms] ) light Higgs is a SM Higgs boson with mh & 140 GeV [other 2HDM heavy] 170 160 LL 150 GeVGeV HH 140 MassMass 130 120 HiggsHiggs 110 2 4 6 8 10 12 14 Log10 Ms GeV H L Tilman Plehn: Split Supersymmetry – p.6 PHYSICS OF SPLIT SUPERSYMMETRY: 2 Heavy scalars and the Higgs mass [Giudice, Romanino; Arvantaki, Davis, Graham, Wacker] » 4 2 2 – known leading corrections increased: mh mZ + GFyt log(m~t =mt ) ) large mh for heavy stops [out of LEP2 reach] 170 160 ) not a precision observable anymore [large logarithms] LL 150 GeVGeV HH 140 ) light Higgs is a SM Higgs boson with mh & 140 GeV MassMass 130 120 HiggsHiggs 110 2 4 6 8 10 12 14 Log10 Ms GeV Heavy scalars and the gluino life time [Arkani-Hamed, Dimopoulos; Giudice, Romanino] H L 30 » e 4 5 10 – decay through squark ¿~g m =m~g 1020 Lifetime of the universe – loop-induced decays? [Toharia, Wells] 10 eV 10 T – lifetime constrained by nucleosynthesis :5 0 eV T = 2 e 9 g~ – m . 10 GeV ¿ mGUT [PeV? Wells] τ [s] 1 m Gluino leaves detector ) −10 gluino hadronizes, decays much later 10 ) Displaced vertex long-lived gluino collider signature No.1 −20 10 Gluino hadronizes 1 105 1010 1015 m~ [GeV] Tilman Plehn: Split Supersymmetry – p.7 PHYSICS OF SPLIT SUPERSYMMETRY: 3 Renormalization group running – argued unification, so make Split Susy a GUT – gauge couplings unify 1000 – gaugino masses as well Gauge couplings Mi [GeV] g3 M3 1 500 g2 M2 g1 M1 0 µ 0 1 105 1010 1015 1 105 1010 1015 Q [GeV] Q [GeV] Tilman Plehn: Split Supersymmetry – p.8 PHYSICS OF SPLIT SUPERSYMMETRY: 3 Renormalization group running – argued unification, so make Split Susy a GUT 1000 Gauge couplings Mi [GeV] – gauge couplings unify g3 M3 1 500 – gaugino masses assumed to unify as well g2 M2 g1 M1 0 µ 0 1 105 1010 1015 1 105 1010 1015 Q [GeV] Q [GeV] Anomalous ino Yukawa coupling – gauginos–higgsinos mixing in MSSM: 0.2 Mixing parameters m~B 0 mZswc¯ ~gdv mZsws¯ ~guv ¡ ´ ¡0 ´ 0 0.1 κ 0 m m cwc¯ ~g v mzcws¯ ~g v d 0 W~ Z ´ d ¡ ´ ¡ u 1 mZswc¯ mZcwc¯ 0 ¹ κu B ¡ ¡ C 0 B m sws¯ m cws¯ ¹ 0 C B Z ¡ Z ¡ C @ A 0 κu 0.1 – Yukawas/gaugino–higgsino mixing fixed by Susy − 0 κd – supersymmetric beta functions broken at Q = me 0.2 − 1 105 1010 1015 Q [GeV] – anomalous Yukawas collider signal No.2: g~=g~MSSM = 1 + · Tilman Plehn: Split Supersymmetry – p.9 PHYSICS OF SPLIT SUPERSYMMETRY: 4 Manuel’s argument [Drees: hep-ph/0501106] » ¡ – remember Higgs potential and B parameter [V ¹B HuHd] ! ¹ protected by symmetry: tan ¯ B ¹ B m m sin 2¯ = 2 = 2 = 2 weak = 2 x weak for B = x m 2 2 2 2 1 + tan ¯ mH;u + mH;d m m e e e ! two solutions: x m m tan ¯ 1 : tan ¯ = weak tan ¯ 1 : tan ¯ = ¿ m x mweak e e ! remember Yukawa couplings: tan ¯ = 1:::100: m m2 tan ¯ < 100 x > B > ) 100 mweak ) 100 mweak e e ! second fine tuning not protected by anything [and pointing to Planck scale] Tilman Plehn: Split Supersymmetry – p.10 SPLIT SUSY AT THE LHC: 1 LHC production of gauginos and higgsinos – cross sections not small [Mj(mGUT) = 120GeV; in fb from Prospino2] ~g~g 1710 ¡ + ¡ + + ¡ + ¡ Â~1 Â~1 2910 Â~1 Â~2 73.7 Â~1 Â~2 73.7 Â~2 Â~2 604 0 0 0 0 0 0 0 0 Â~1Â~1 49.4 Â~1Â~2 49.7 Â~1Â~3 409 Â~1Â~4 0.06 0 0 0 0 0 0 Â~2Â~2 5.0 Â~2Â~3 876 Â~2Â~4 3.7 0 0 0 0 Â~3Â~3 1.4 Â~3Â~4 69.6 0 0 Â~4Â~4 1.0 ¡ 0 ¡ 0 ¡ 0 ¡ 0 Â~1 Â~1 584 Â~1 Â~2 1780 Â~1 Â~3 789 Â~1 Â~4 78.8 + 0 + 0 + 0 + 0 Â~1 Â~1 914 Â~1 Â~2 2870 Â~1 Â~3 1310 Â~1 Â~4 138 ¡ 0 ¡ 0 ¡ 0 ¡ 0 Â~2 Â~1 2.7 Â~2 Â~2 55.9 Â~2 Â~3 66.6 Â~2 Â~4 430 + 0 + 0 + 0 + 0 Â~2 Â~1 4.5 Â~2 Â~2 97.7 Â~2 Â~3 119 Â~2 Â~4 798 – but best background rejection m`` gone with the wind [higgsino searches?] What’s new for LHC phenomenology? – no squarks, sleptons for cascades [Giudice, Romanino; astro-particle: Pierce] – stable (hadronizing) gluinos [¿ » m¡4 » 6:5s for m = 109GeV, LHC time scale 25 ns] – heavy hadrons Rg; Rq¹q; Rqqq [Farrare, Fayet 1978; Baer,eCheung, Gunion 1999; UKQCD 1999] – gluinonium [Kühn, Ono 1984; Goldman, Haber 1985; Cheung] Tilman Plehn: Split Supersymmetry – p.11 SPLIT SUSY AT THE LHC: 2 Charged R hadrons – many gluinos pair-produced [ & 1 pb] – charged R hadrons in tracker, calorimeter, muon chambers [Cambridge ex-th] – level-1 trigger without muon chamber? [25...75 ns delay] – effect of conversion to R baryons because of light pions? [Kraan] ) fraction of charged R hadrons crucial ) effective (not calculable) parameter PRg Tilman Plehn: Split Supersymmetry – p.12 SPLIT SUSY AT THE LHC: 2 Charged R hadrons – many gluinos pair-produced [ & 1 pb] – charged R hadrons in tracker, calorimeter, muon chambers [Cambridge ex-th] – level-1 trigger without muon chamber? [25...75 ns delay] – effect of conversion to R baryons because of light pions? [Kraan] ) fraction of charged R hadrons crucial ) effective (not calculable) parameter PRg Beyond BSM signal – mass measurement through time of flight – charge flipper [Kraan; Hewett, Rizzo,...] – energy deposition: no heavy lepton Tilman Plehn: Split Supersymmetry – p.13 SPLIT SUSY AT THE LHC: 3 Neutral R hadrons – jets plus missing energy [» 10% energy loss] – trigger dependent on cross section in calorimeter – improved in combination with charged R hadron [missing energy trigger] – mass measurement from gluinonium – R hadron flavor physics? ) charged R hadrons preferable Tilman Plehn: Split Supersymmetry – p.14 SPLIT SUSY AT THE LHC: 3 Neutral R hadrons – jets plus missing energy [» 10% energy loss] – trigger dependent on cross section in calorimeter – improved in combination with charged R hadron [missing energy trigger] – mass measurement from gluinonium – R hadron flavor physics? ) charged R hadrons preferable Tilman Plehn: Split Supersymmetry – p.15 SPLIT SUPERSYMMETRY AT THE ILC: 1 Signals at the ILC – gluinos not produced because of decoupled squarks – neutralino–chargino sector analysis as usual [robust with changed decay channels] 0 0 » – measurement of anomalous Yukawas [~gu;~gd;~gu;~gd different by 10%] ) (1) direct measurements of ÂÂH 10 e−ν¯W +H σtot[fb] + e e−
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