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 Λ all–orders Higgs mass driven to cutoff mh → Λ ⇒ 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 G 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 o 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 → 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: m ˜0 m + or m ˜0 m + in MSSM 2 ˜1 1 ˜1
m 0 m swc m sws ˜B Z Z 0 m m cwc mzcws m √2m cws 0 W˜ Z 1 W˜ Z mZswc mZcwc 0 √2mZcwc ! B C B m sws m cws 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 ˜1, ˜ 0 ˜ ˜ ⇒ after dark matter data ˜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 ] ˜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 κu B C 0 B m sws m cws 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 B HuHd] → protected by symmetry: tan B 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 + + + + ˜1 ˜1 2910 ˜1 ˜2 73.7 ˜1 ˜2 73.7 ˜2 ˜2 604 0 0 0 0 0 0 0 0 ˜1 ˜1 49.4 ˜1 ˜2 49.7 ˜1 ˜3 409 ˜1 ˜4 0.06 0 0 0 0 0 0 ˜2 ˜2 5.0 ˜2 ˜3 876 ˜2 ˜4 3.7 0 0 0 0 ˜3 ˜3 1.4 ˜3 ˜4 69.6 0 0 ˜4 ˜4 1.0 0 0 0 0 ˜1 ˜1 584 ˜1 ˜2 1780 ˜1 ˜3 789 ˜1 ˜4 78.8 + 0 + 0 + 0 + 0 ˜1 ˜1 914 ˜1 ˜2 2870 ˜1 ˜3 1310 ˜1 ˜4 138 0 0 0 0 ˜2 ˜1 2.7 ˜2 ˜2 55.9 ˜2 ˜3 66.6 ˜2 ˜4 430 + 0 + 0 + 0 + 0 ˜2 ˜1 4.5 ˜2 ˜2 97.7 ˜2 ˜3 119 ˜2 ˜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, Rq¯q, 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 H 10 e−ν¯W +H σtot[fb] + e e− χ˜χH˜ → νν¯ZH 1
+ − χ˜1 χ˜1 H 0.1 + − χ˜1 χ˜2 H
e−ν¯W +ZH
0 0 χ˜3χ˜4H 0.01 νν¯ZZH
0 0 χ˜1χ˜3H 0 0 χ˜1χ˜2H
0.001 200 400 600 800 1000 1200 1400 √s [GeV]
Tilman Plehn: Split Supersymmetry – p.16 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]
10 e−ν¯W +H σtot[fb] 0 0 + e e− χ˜χH˜ – measurement of anomalous Yukawas [˜gu,˜g ,˜g ,˜g ] → d u d νν¯ZH 1 ⇒ (1) direct measurements of H [Whizard, Smadgraph; unpromising!] + − χ˜1 χ˜1 H 0.1 + − χ˜1 χ˜2 H
e−ν¯W +ZH
(2) indirect determination of mass matrices 0 0 χ˜3χ˜4H 0.01 νν¯ZZH
0 0 χ˜1χ˜3H 0 0 χ˜1χ˜2H
0.001 200 400 600 800 1000 1200 1400 √s [GeV] Extracting parameters from neutralino/chargino sector – 104 smeared measurements of six masses (and cross sections) 4 – 10 fits of M1, M2, and one or more i
– LHC data alone not promising [masses only, 5% error]
800 500 700 600 8000 800 LHC 600 400 500 300 6000 600 400 400 200 300 4000 400 200 200 100 100 2000 200 0 0 0 0 0 55 95 150 210 -140 -100 3 5 -0.5 0.5 [ ] [ ] µ[ ] β κ M1 GeV M2 GeV GeV tan u Tilman Plehn: Split Supersymmetry – p.17 SPLIT SUPERSYMMETRY AT THE ILC: 2
Neutralinos/charginos at the ILC – mass measurements to 0.5% – error propagation through 104 smeared pseudo-measurements ⇒ one at the time to . 5%
1750 1400 1200 1750 1500 800 1200 1000 1500 LC 1250 1000 1250 600 800 1000 1000 800 600 750 400 600 750 400 500 200 400 500 250 200 200 250 0 0 0 0 0 70 80 173 183 -125 -115 3 5 -0.1 0.1 [ ] [ ] µ[ ] β κ M1 GeV M2 GeV GeV tan u
Tilman Plehn: Split Supersymmetry – p.18 SPLIT SUPERSYMMETRY AT THE ILC: 2
Neutralinos/charginos at the ILC – mass measurements to 0.5%, cross sections statistical error – error propagation through 104 smeared pseudo-measurements ⇒ one at the time to . 5% ⇒ four simultaneously to . 10%
1000 3000 800 1400 800 LC 2500 1200 800 600 2000 1000 600 600 800 1500 400 600 400 400 1000 200 400 200 200 500 200 0 0 0 0 0 173 183 -0.2 0.2 -0.2 0.2 -0.2 0.2 -0.4 0.4 [ ] κ κ κ κ ' M2 GeV u d u' d 2500 700 800 600 1000 600 LC 2000 500 800 500 600 1500 400 600 400 300 400 1000 300 400 200 200 200 500 100 200 100 0 0 0 0 0 173 183 -0.18 0.22 -0.12 0.28 -0.28 0.12 -0.57 0.23 [ ] κ κ κ κ M2 GeV u d u' d'
Tilman Plehn: Split Supersymmetry – p.19 SPLIT SUPERSYMMETRY AT THE ILC: 2
Neutralinos/charginos at the ILC – mass measurements to 0.5%, cross sections statistical error – error propagation through 104 smeared pseudo-measurements ⇒ one at the time to . 5% ⇒ four simultaneously to . 10%
So can we tell it is Split Susy? – mass measurement errors conservative
– only mass and cross section measurements yet [Sfitter-Fittino next step]
Fit tan m 0 0 i ij ∆ u ∆ d ∆ u ∆ d ILC 0.9 10 2 3 10 2 1.3 10 2 4 10 2 ILC 1.2 10 2 5 10 2 2 10 2 5 10 2 ILC 1.1 10 2 5 10 2 3 10 2 8 10 2 ILC 1.2 10 2 11 10 2 4 10 2 8 10 2 LHC 2.2 10 1 6 10 1 2.7 10 1 8 10 1
ILC 1.4 10 2 5 10 2 3 10 2 10 10 2 ILC 1.7 10 2 9 10 2 4 10 2 13 10 2 ILC fix tan = 3 1.6 10 2 4 10 2 4 10 2 9 10 2 2 2 2 2 ILC i =6 0 1.4 10 5 10 4 10 11 10 ILC fix tan = 5 1.6 10 2 7 10 2 4 10 2 14 10 2 ⇒ anomalous Yukawas promising at ILC Tilman Plehn: Split Supersymmetry – p.20 OUTLOOK
Showcase for state-of-the-art LHC phenomenology: Split Supersymmetry – interesting phenomenology – LHC: R hadrons observable with mass measurement – ILC: anomalous weak-ino Yukawas accessible
What stays
– exotic heavy hadrons visible at LHC [trigger issues]
– why did we aways assume MSSM-type ino Yukawas? [missed Susy test]
Tilman Plehn: Split Supersymmetry – p.21 SUSY-MADGRAPH
SUSY-Madgraph: we are done! [Hagiwara, Kanzaki, TP, Rainwater, Stelzer]
– Majoranas and fermion number violation in Madgraph [Denner, Eck, Hahn, Küblbeck]
– complete set of Feynman rules [300+ processes compared with Whizard and Sherpa] – beta version upon request, Smadevent in test phase – first physics project: SUSY pairs in WBF
Using SUSY-Madevent: squarks and gluinos plus jets [TP, Rainwater, Skands] – cascade studies sensitive to hard jet radiation? -1 10 1/σ dσ/dp : pp → gÄgÄnj – compute g˜g+2j˜ and u˜Lg+2j˜ [SPS1a, pT,j > 100GeV] T,j
[pb] t¯t600 ˜g˜g ˜uL˜g -2 10 0j 1.30 4.83 5.65 max gÄgÄjj: pT,j 1j 0.73 2.89 2.74 2j 0.26 1.09 0.85 -3 10 gÄgÄj: pT,j
min – task 1: gluon radiation vs. initial states? gÄgÄjj: pT,j -4 – task 2: comparison with Phythia showers 10 100 200 300 400 500 [ ] pT,j GeV
Tilman Plehn: Split Supersymmetry – p.22 SUSY-MADGRAPH
SUSY-Madgraph: we are done! [Hagiwara, Kanzaki, TP, Rainwater, Stelzer]
– Majoranas and fermion number violation in Madgraph [Denner, Eck, Hahn, Küblbeck]
– complete set of Feynman rules [300+ processes compared with Whizard and Sherpa] – beta version upon request, Smadevent in test phase – first physics project: SUSY pairs in WBF
Using SUSY-Madevent: squarks and gluinos plus jets [TP, Rainwater, Skands] – cascade studies sensitive to hard jet radiation? -1 10 1/σ dσ/dp : pp → uÄ gÄjj – compute g˜g+2j˜ and u˜Lg+2j˜ [SPS1a, pT,j > 100GeV] T,j L
[pb] t¯t600 ˜g˜g ˜uL˜g -2 10 0j 1.30 4.83 5.65 max uÄLgÄjj: pT,j 1j 0.73 2.89 2.74 2j 0.26 1.09 0.85 -3 10 uÄLgÄj: pT,j
min – task 1: gluon radiation vs. initial states? uÄLgÄjj: pT,j -4 – task 2: comparison with Phythia showers 10 100 200 300 400 500 [ ] pT,j GeV
Tilman Plehn: Split Supersymmetry – p.23 SUSY-MADGRAPH
SUSY-Madgraph: we are done! [Hagiwara, Kanzaki, TP, Rainwater, Stelzer]
– Majoranas and fermion number violation in Madgraph [Denner, Eck, Hahn, Küblbeck]
– complete set of Feynman rules [300+ processes compared with Whizard and Sherpa] – beta version upon request, Smadevent in test phase – first physics project: SUSY pairs in WBF
Using SUSY-Madevent: squarks and gluinos plus jets [TP, Rainwater, Skands] – cascade studies sensitive to hard jet radiation? -1 10 ± 1/σ dσ/dp : pp → ttnj – compute g˜g+2j˜ and u˜Lg+2j˜ [SPS1a, pT,j > 100GeV] T,j
[pb] t¯t600 ˜g˜g ˜uL˜g -2 10 ± 0j 1.30 4.83 5.65 max ttjj: pT,j 1j 0.73 2.89 2.74 2j 0.26 1.09 0.85 -3 ± 10 ttj: pT,j
± min – task 1: gluon radiation vs. initial states? ttjj: pT,j mt=600 GeV -4 – task 2: comparison with Phythia showers 10 100 200 300 400 500 [ ] pT,j GeV
Tilman Plehn: Split Supersymmetry – p.24 SUSY-MADGRAPH
SUSY-Madgraph: we are done! [Hagiwara, Kanzaki, TP, Rainwater, Stelzer]
– Majoranas and fermion number violation in Madgraph [Denner, Eck, Hahn, Küblbeck]
– complete set of Feynman rules [300+ processes compared with Whizard and Sherpa] – beta version upon request, Smadevent in test phase – first physics project: SUSY pairs in WBF
Using SUSY-Madevent: squarks and gluinos plus jets [TP, Rainwater, Skands]
LHC: ttbar + 2 jets CTEQ5L, no K-factors – cascade studies sensitive to hard jet radiation? MadGraph: ttbar + 2 jets 2 Pythia 6.3: pT (power) 2 Pythia 6.3: pT (wimpy) 2
(pb/GeV) 1 Pythia 6.2: Q (power) – compute g˜g+2j˜ and u˜Lg+2j˜ [SPS1a, pT,j > 100GeV] T Pythia 6.2: Q2 (wimpy) /dp σ d Max Jet pT E ≥50GeV, |η|<5, ∆R=0.4 [pb] t¯t600 ˜g˜g ˜uL˜g Tjet 0j 1.30 4.83 5.65 1j 0.73 2.89 2.74 2j 0.26 1.09 0.85
-1 – task 1: gluon radiation vs. initial states? 10 – task 2: comparison with Phythia showers 60 80 100 120 140 160 180 200 220 240
Max Jet pT (GeV)
Tilman Plehn: Split Supersymmetry – p.25