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Light higgsino models and parameter determination

Krzysztof Rolbiecki IFT-CSIC, Madrid

in collaboration with: Mikael Berggren, Felix Brummer,¨ Jenny List, Gudrid Moortgat-Pick, Hale Sert and Tania Robens

ECFA Linear Collider Workshop 2013 27–31 May 2013, DESY, Hamburg

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 1 / 21 SUSY @ LHC

What does LHC tell us about 1st/2nd gen. squarks? → quite heavy and stop searches model dependent – limits weaker

ATLAS SUSY Searches* - 95% CL Lower Limits ATLAS Preliminary Status: LHCP 2013 ∫Ldt = (4.4 - 20.7) fb-1 s = 7, 8 TeV miss -1 Model e, µ, τ, γ Jets ET ∫Ldt [fb ] Mass limit Reference

~ ~ ~ ~ MSUGRA/CMSSM 0 2-6 jets Yes 20.3 q, g 1.8 TeV m(q)=m(g) ATLAS-CONF-2013-047 ~ ~ ~ ~ MSUGRA/CMSSM 1 e, µ 4 jets Yes 5.8 q, g 1.24 TeV m(q)=m(g) ATLAS-CONF-2012-104 ~ ~ MSUGRA/CMSSM 0 7-10 jets Yes 20.3 g 1.1 TeV any m(q) ATLAS-CONF-2013-054 ~~ ~ ∼0 ~ ∼ qq, q→qχ 0 2-6 jets Yes 20.3 m(χ0 ) = 0 GeV ATLAS-CONF-2013-047 1 q 740 GeV 1 ~~ ~ ∼0 ~ ∼ gg, g→qqχ 0 2-6 jets Yes 20.3 m(χ0 ) = 0 GeV ATLAS-CONF-2013-047 1 g 1.3 TeV 1 ∼± ~ ∼± ~ ∼ ∼ ± ∼ ~ med. χ (g→qqχ ) 1 e, µ 2-4 jets Yes 4.7 g 900 GeV m(χ 0 ) < 200 GeV, m(χ ) = 0.5(m(χ 0 )+m( g)) 1208.4688 ~~ ∼ ∼ ∼ 1 1 → χ0χ 0 µ ~ χ 0 gg qqqqll(ll) 2 e, (SS) 3 jets Yes 20.7 g 1.1 TeV m( 1 ) < 650 GeV ATLAS-CONF-2013-007 ~ 1 1 ~ GMSB (l NLSP) 2 e, µ 2-4 jets Yes 4.7 g 1.24 TeV tanβ < 15 1208.4688 ~ ~ GMSB (l NLSP) 1-2 τ 0-2 jets Yes 20.7 tanβ >18 ATLAS-CONF-2013-026

Inclusive searches g 1.4 TeV ∼ γ ~ χ 0 GGM (bino NLSP) 2 0 Yes 4.8 g 1.07 TeV m( 1 ) > 50 GeV 1209.0753 ~ ∼ GGM (wino NLSP) 1 e, µ + γ 0 Yes 4.8 g 619 GeV m(χ 0 ) > 50 GeV ATLAS-CONF-2012-144 ∼ 1 γ ~ χ 0 GGM (higgsino-bino NLSP) 1 b Yes 4.8 g 900 GeV m( 1 ) > 220 GeV 1211.1167 ~ ~ GGM (higgsino NLSP) 2 e, µ (Z) 0-3 jets Yes 5.8 g 690 GeV m(H) > 200 GeV ATLAS-CONF-2012-152 ~ LSP 0 mono-jet Yes 10.5 F 1/2 scale 645 GeV m(G) > 10-4 eV ATLAS-CONF-2012-147 ~ ∼ ~ ∼ g→bbχ0 0 3 b Yes 12.8 g 1.24 TeV m(χ 0 ) < 200 GeV ATLAS-CONF-2012-145 ~ ∼ 1 ~ ∼ 1 g→ttχ0 2 e, µ (SS) 0-3 b No 20.7 g 900 GeV m(χ 0 ) < 500 GeV ATLAS-CONF-2013-007 ∼1 ∼ 1

gen. ~ ~ g→ttχ0 0 7-10 jets Yes 20.3 g 1.14 TeV m(χ 0 ) <200 GeV ATLAS-CONF-2013-054 med. 1 rd ~ ∼1 ~ ∼ ~ 0 0 3 g g→ttχ 0 3 b Yes 12.8 g 1.15 TeV m(χ ) < 200 GeV ATLAS-CONF-2012-145 1 1 ~ ~ ~ ∼ ~ ∼ b b , b →bχ0 0 2 b Yes 20.1 m(χ 0 ) < 100 GeV ATLAS-CONF-2013-053 1 1 1 1 b 1 100-630 GeV 1 ~ ~ ~ ∼± ~ ∼ ∼ b b , b →tχ 2 e, µ (SS) 0-3 b Yes 20.7 m(χ ± ) = 2 m(χ 0 ) ATLAS-CONF-2013-007 1 1 1 1 b 1 430 GeV 1 1 ~~ ~ ∼± ~ ∼ → χ µ χ 0 t1t1 (light), t1 b 1-2 e, 1-2 b Yes 4.7 t 167 GeV m( 1 ) = 55 GeV 1208.4305, 1209.2102 ~~ ~ 1∼ ~1 ∼ ~ ~ ∼ t t (light), t →Wbχ 0 2 e, µ 0-2 jets Yes 20.3 m(χ 0 ) = m(t ) - m(W) - 50 GeV, m(t ) << m(χ ± ) ATLAS-CONF-2013-048 1 1 1 1 t 1 220 GeV 1 1 1 1 ~~ ~ ∼± ~ ∼ ~ ∼ t t (medium), t →bχ 2 e, µ 0-2 jets Yes 20.3 m(χ 0 ) = 0 GeV, m(t )-m(χ ± ) = 10 GeV ATLAS-CONF-2013-048 1 1 1 1 t 1 150-440 GeV 1 1 1 ~~ ~ ∼± ~ ∼ ∼ ∼ t t (medium), t →bχ 0 2 b Yes 20.1 t 150-580 GeV m(χ 0 ) < 200 GeV, m(χ ± )-m( χ ± ) = 5 GeV ATLAS-CONF-2013-053 ~1~1 ~ 1 ∼ 1 ~1 ∼ 1 1 1 t t (heavy), t →tχ0 1 e, µ 1 b Yes 20.7 t 200-610 GeV m(χ 0 ) = 0 GeV ATLAS-CONF-2013-037 ~1~1 ~1 ∼1 1 ∼ 1

gen. squarks ~ → χ0 χ 0 t1t1 (heavy), t1 t 0 2 b Yes 20.5 t 320-660 GeV m( 1 ) = 0 GeV ATLAS-CONF-2013-024 rd ~~ 1 1 ∼ ~ 0 3 direct production µ χ t1t1 (natural GMSB) 2 e, (Z) 1 b Yes 20.7 t 500 GeV m( 1 ) > 150 GeV ATLAS-CONF-2013-025 ~ ~ ~ ~ ~1 ~ ∼ t t , t →t +Z 3 e, µ (Z) 1 b Yes 20.7 m(t ) = m(χ 0 ) + 180 GeV ATLAS-CONF-2013-025 2 2 2 1 t 2 520 GeV 1 1 ~ ~ ~ ∼0 ~ ∼ lL,RlL,R, l→lχ 2 e, µ 0 Yes 20.3 l 85-315 GeV m(χ 0 ) = 0 GeV ATLAS-CONF-2013-049 ∼ ∼ ∼ ~ 1∼ ∼ ∼ 1 ~∼ ∼ ∼ χ+χ- χ+→ ν ν µ ± χ 0 ν χ ± χ 0 , l (l ) 2 e, 0 Yes 20.3 χ 125-450 GeV m( 1 ) = 0 GeV, m(l, ) = 0.5(m( 1 ) + m( 1 )) ATLAS-CONF-2013-049 ∼1∼1 ∼1 ∼ ∼ ∼1 ∼ ∼ ∼ ∼ ∼ χ+ χ -, χ+ → τν (τν ) 2 τ 0 Yes 20.7 χ± 180-330 GeV m(χ 0 ) = 0 GeV, m(τ,ν ) = 0.5(m(χ ± ) + m(χ 0 )) ATLAS-CONF-2013-028 ∼1∼1 1 ~ ~ ∼ ∼~ ∼ ∼1 ∼ ∼ ∼ 1 ∼ ~ ∼ ∼ 1 ∼ 1 ± 0 ± ± 0 0 ± 0 EW direct χ χ → l ν l l(ν ν ), lν l l(ν ν ) 3 e, µ 0 Yes 20.7 χ χ0 m(χ ) = m(χ ), m(χ ) = 0, m(l,ν ) = 0.5(m(χ ) + m(χ )) ATLAS-CONF-2013-035 1 2 L L L , 600 GeV 1 2 1 1 1 ∼±∼ ∼ (*) ∼ ∼1 ∼2 ∼ ∼ ∼ χ χ 0 → W(*) χ 0 Z χ0 3 e, µ 0 Yes 20.7 χ± , χ0 315 GeV m(χ ± ) = m(χ 0 ), m(χ 0 ) = 0, sleptons decoupled ATLAS-CONF-2013-035

1 2 1 1 1 2 1 2 1 ∼±∼ ± ∼ ± ∼± ∼ Direct χ χ prod., long-lived χ 0 1 jet Yes 4.7 χ 220 GeV 1 < τ(χ ± ) < 10 ns 1210.2852 ~1 1 1 ~1 1 Stable g, R- 0-2 e, µ 0 Yes 4.7 g 985 GeV 1211.1597 ∼ ∼ GMSB, stable τ, low β 2 e, µ 0 Yes 4.7 τ 300 GeV 5 < tanβ < 20 1211.1597 ∼ ~ ∼ ∼ ∼ GMSB, χ0 → γ G,long-lived χ 0 2 γ 0 Yes 4.7 χ0 230 GeV 0.4 < τ(χ 0 ) < 2 ns 1304.6310 ∼ 1 1 1 1 χ0 → µ µ ~ τ ~

Long-lived qq (RPV) 1 e, 0 Yes 4.4 1 mm < c < 1 m, g decoupled 1210.7451 1 q 700 GeV

∼ ∼ ∼ , LFV pp→ν τ +X, ν τ →e+µ 2 e, µ 0 - 4.6 ν τ 1.61 TeV λ =0.10, λ =0.05 1212.1272 ∼ ∼ ∼ 311 132 →ν ν → µ τ µ τ λ , λ LFV pp τ +X, τ e( )+ 1 e, + 0 - 4.6 ν τ 1.1 TeV 311=0.10, 1(2)33=0.05 1212.1272 µ ~ ~ ~ ~ τ Bilinear RPV CMSSM 1 e, 7 jets Yes 4.7 q, g 1.2 TeV m(q) = m(g), c LSP < 1 mm ATLAS-CONF-2012-140 ∼+∼- ∼+ ∼0 ∼ 0 ∼± ∼ χ χ , χ → Wχ , χ →eeν µ,eµν 4 e, µ 0 Yes 20.7 χ 760 GeV m(χ 0 ) > 300 GeV, λ > 0 ATLAS-CONF-2013-036 1 1 1 1 1 e 1 1 121 ∼ ∼ ∼ ∼ ∼ ∼± ∼ RPV χ+χ- χ+→ χ0 χ 0→ττν τν µ τ χ 0 λ , W , e,e τ 3 e, + 0 Yes 20.7 χ 350 GeV m( 1 ) > 80 GeV, 133 > 0 ATLAS-CONF-2013-036 ~1 1 1 1 1 ~1 g → qqq 0 6 jets - 4.6 g 666 GeV 1210.4813 ~ ~ ~→ → µ ~ g t1t, t1 bs 2 e, (SS) 0-3 b Yes 20.7 g 880 GeV ATLAS-CONF-2013-007

Scalar 0 4 jets - 4.6 sgluon 100-287 GeV incl. limit from 1110.2693 1210.4826 WIMP interaction (D5, Dirac χ) 0 mono-jet Yes 10.5 M* scale 704 GeV m(χ) < 80 GeV, limit of < 687 GeV for D8 ATLAS-CONF-2012-147 Other s = 7 TeV s = 8 TeV s = 8 TeV 10-1 1 full data partial data full data Mass scale [TeV] *Only a selection of the available mass limits on new states or phenomena is shown. All limits quoted are observed minus 1σ theoretical signal cross section uncertainty.

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 2 / 21 Outline

1 Light higgsinos from gauge-gravity mediation

2 Light higgsinos at colliders

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 3 / 21 Outline

1 Light higgsinos from gauge-gravity mediation

2 Light higgsinos at colliders

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 4 / 21 Light higgsinos

L = µ H˜ H˜ + +m2 + |µ|2 |H |2 +m2 + |µ|2 |H |2 +... MSSM u d h.c. Hu u Hd d

Higgsino mass parameter µ is special: supersymmetric

A priori µ is unrelated to the scale of SUSY breaking

µ cannot be too small (LEP bound: m ± 100 GeV) χ1 & µ should not be too large:

2 2 2 2 mZ = −2 mHu − 2|µ| + O(cot β)

2 2 2 If |mHu |, |µ|  mZ ⇒ large cancellation needed ⇒ Fine-tuning!

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 4 / 21 Light higgsinos

Two approaches: µ generated supersymmetrically, around EW scale by coincidence effective µ generated by SUSY breaking in calculable models: µ/Bµ problem ⇒ µ still special

Naturalness wants µ around 100 GeV:

2 2 2 2 mZ = −2 mHu − 2|µ| + O(cot β)

LHC bounds want squarks and above 1 TeV. Motivates studying scenarios where higgsinos are light (EW scale) while everything else is heavy (multi-TeV) except maybe 3rd generation 0 ± 0 light higgsinos = near-degenerate χ1, χ1 , χ2 around 100–200 GeV

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 5 / 21 Gauge med.: µ = 0, SUSY MSSM M g2 hidden sector m ∼ m · N · Planck · soft 3/2 mess. M 16π2 mess. messenger fields with SM gauge charges

Models with GUT-scale extra dimensions: typically include superheavy “exotic ”: candidate messengers g2 masses: M ≈ M ≈ M · mess. GUT Planck 16π2 multiplicities: Nmess. ∼ O(few tens)

Hybrid gauge-gravity mediation in higher-dim. GUTs:→ Brummer,Buchm¨ uller¨ ’11,’12

µ ∼ m3/2 ∼ O(100 GeV), msoft ∼ Nmess. · m3/2 ∼ O(TeV)

Light higgsinos from hybrid gauge-gravity mediation Light higgsinos from hybrid gauge-gravity mediation SUSY hidden sector MSSM Gravity med.: µ ∼ m3/2, → Giudice/Masiero ’88

msoft ∼ m3/2 M Planck −suppressed interactions

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 6 / 21 Models with GUT-scale extra dimensions: typically include superheavy “”: candidate messengers g2 masses: M ≈ M ≈ M · mess. GUT Planck 16π2 multiplicities: Nmess. ∼ O(few tens)

Hybrid gauge-gravity mediation in higher-dim. GUTs:→ Brummer,Buchm¨ uller¨ ’11,’12

µ ∼ m3/2 ∼ O(100 GeV), msoft ∼ Nmess. · m3/2 ∼ O(TeV)

Light higgsinos from hybrid gauge-gravity mediation Light higgsinos from hybrid gauge-gravity mediation SUSY hidden sector MSSM Gravity med.: µ ∼ m3/2, → Giudice/Masiero ’88

msoft ∼ m3/2 M Planck −suppressed interactions

Gauge med.: µ = 0, SUSY MSSM M g2 hidden sector m ∼ m · N · Planck · soft 3/2 mess. M 16π2 mess. messenger fields with SM gauge charges

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 6 / 21 Light higgsinos from hybrid gauge-gravity mediation Light higgsinos from hybrid gauge-gravity mediation SUSY hidden sector MSSM Gravity med.: µ ∼ m3/2, → Giudice/Masiero ’88

msoft ∼ m3/2 M Planck −suppressed interactions

Gauge med.: µ = 0, SUSY MSSM M g2 hidden sector m ∼ m · N · Planck · soft 3/2 mess. M 16π2 mess. messenger fields with SM gauge charges

Models with GUT-scale extra dimensions: typically include superheavy “exotic matter”: candidate messengers g2 masses: M ≈ M ≈ M · mess. GUT Planck 16π2 multiplicities: Nmess. ∼ O(few tens)

Hybrid gauge-gravity mediation in higher-dim. GUTs:→ Brummer,Buchm¨ uller¨ ’11,’12

µ ∼ m3/2 ∼ O(100 GeV), msoft ∼ Nmess. · m3/2 ∼ O(TeV)

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 6 / 21 A mass spectrum from hybrid gauge-gravity mediation

mass [GeV] h0 124 0 χ1 164 ± χ1 166 0 χ2 167 0 χ3 2700 0 χ4 4100 ± χ2 4100 H0 2200 A0 2200 H± 2200 g˜ 4200 τ˜1 1900 other sleptons 2500 − 3600 squarks 2700 − 5000

tan β = 44

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 7 / 21 Y =   M1 0 −MZ cβsW MZ sβsW  0 M2 MZ cβcW −MZ sβcW     −MZ cβsW MZ cβcW 0 −µ  diagonalised via ∗ † MZ sβsW −MZ sβcW −µ 0 Mχ˜0 = N YN

M1,M2 ∼ O(TeV), µ ∼ O(100 GeV)

Quick recap: chargino and Sector

− ∗ † † T − Lχ˜ =χ˜i (6p δij − ωL(U XV )ij − ωR(VX U )ij)˜χj 1 + χ˜0(6p δ − ω (N ∗YN †) − ω (NY †N T ) )˜χ0 2 i ij L ij R ij j

 √  M2 2MW sin β diagonalised via X = √ ∗ † 2MW cos βµ Mχ˜+ = U XV

0 1 where we define ωL/R = 2 (1 ∓ γ5) Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 8 / 21 Quick recap: chargino and neutralino Sector

− ∗ † † T − Lχ˜ =χ˜i (6p δij − ωL(U XV )ij − ωR(VX U )ij)˜χj 1 + χ˜0(6p δ − ω (N ∗YN †) − ω (NY †N T ) )˜χ0 2 i ij L ij R ij j

 √  M2 2MW sin β diagonalised via X = √ ∗ † 2MW cos βµ Mχ˜+ = U XV

Y =   M1 0 −MZ cβsW MZ sβsW  0 M2 MZ cβcW −MZ sβcW     −MZ cβsW MZ cβcW 0 −µ  diagonalised via ∗ † MZ sβsW −MZ sβcW −µ 0 Mχ˜0 = N YN

M1,M2 ∼ O(TeV), µ ∼ O(100 GeV)

0 1 where we define ωL/R = 2 (1 ∓ γ5) Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 8 / 21 Approximate mass eigenstates

0 1 ˜0 ˜0  sin β + cos β mZ sin β + cos β mZ 0 χ˜1 = √ hd − hu + √ sin θw Be − √ cos θw Wf 2 2 M1 2 M2 0 1 ˜0 ˜0  sin β − cos β mZ sin β − cos β mZ 0 χ˜2 = √ hd + hu − √ sin θw Be + √ cos θw Wf 2 2 M1 2 M2 √ + ˜+ mW + χ˜1 = hu − 2 sin β Wf M2 with masses given by

2  2 2  mZ 2 sin θw cos θw Mχ˜0 = |µ| ∓ (cos β ± sign(µ) sin β) + 1,2 2 M1 M2 2 2 mZ Mχ˜± = |µ| − sin 2β sign(µ) cos θw 1 M2

± and the mass difference between chargino χ˜1 and the LSP   2 2   2 2    2 sin 2β sin θw cos θw 1 sin θw cos θw µ M ± −M 0 = mZ − + + + O χ˜ χ˜1 2 1 2 M1 M2 2 M1 M2 Mi

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 9 / 21 Outline

1 Light higgsinos from gauge-gravity mediation

2 Light higgsinos at colliders

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 10 / 21 Higgsinos + monojets

jet _ _ + q W χ0 +_ 2 χ 0 1 χ MET 1 + +_ invisible Z W q 0 χ1

Monojet (and -) signal at ATLAS and CMS Usual interpretation of j+MET: generic WIMP with contact interaction !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! q !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! χ !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!!! !!!!! !!!!! !!!!! !!!!! !!!!! !!!!!! !!!!! !!!!! !!!!! !!!!!! !!!!! !!!!! !!!!!! !!!!! !!!!! !!!!!! !!!!! !!!!! !!!!!! !!!!! !!!!! !!!!! !!!!!! !!!!! !!!!!! _ !!!!! !!!!!! !!!!! !!!!!! !!!!! !!!!!! q !!!!! !!!!!! χ

Should also provide mass limits for higgsinos!

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 10 / 21 Linear collider

Detailed parameter measurements require linear collider → Baer/Barger/Huang ’11; Berggren/Brummer/List/Moortgat-Pick/Rolbiecki/Sert,¨ in preparation

Two benchmark scenarios with hybrid gauge-gravity mediation:

mh0 124 mh0 127 mχ0 164.2 m 0 166.6 1 χ1 mχ± 165.8 m ± 167.4 1 χ1 mχ0 166.9 m 0 167.6 2 χ2 M1 1700 M1 5300 M2 4400 M2 9500 µ 166 µ 166

+ − 0 0 √ production of χ˜1 χ˜1 and χ˜2χ˜1 already at s = 350 GeV small mass splittings ⇒ , soft γs

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 11 / 21 Production at the ILC

- ˜ 1 ˜ - ˜ - 1 1 e e e + + ˜ e ˜ 1 ˜ 1 + Z ˜ e e 1 e 0 ˜ 1 ˜ 0 ˜ 0 1 e e 1 e s s ˜ 0 e˜ e˜ ˜ 0 Z 2 0 2 e ˜ 2 e e

0 0 0 0 0 0 only χ˜1χ˜2 produced: Z couplings forbid χ˜1χ˜1 and χ˜2χ˜2 for higgsinos the t and u slepton exchange proportional to Yukawa coupling ⇒ negligible for higgsinos ⇒ heavy sleptons in our scenarios but even for light ones they would not contribute

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 12 / 21 Higgsino decays

0 0 neutralino decays via off-shell Z or two-body χ˜2 → χ˜1γ for low mass difference the latter loop induced dominates ± 0 ∗ 0 0 chragino decays with off-shell W boson χ˜1 → χ˜1W → χ˜1ff lifetime up to ∼ 10−12 s ⇒ decay length cτ ∼ 10−3 m in scenarios with small mass difference one can look for displaced vertices two approaches to calculate decay modes: calculate parton level matrix element (e.g. with Whizard) and hadronize with Pythia use hadronic currents like for τ decays, implemented in Herwig++ give very different results...

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 13 / 21 Chargino decays

Pythia hadronization vs Herwig++ hadronic currents mh = 124 GeV; ∆m = 1.6 GeV Pythia Herwig++ mh = 127 GeV; ∆m = 0.7 GeV decay 0 decay Pythia Herwig++ χ˜1`ν 40% 33% 0 χ˜0π+ 10% 17% χ˜1`ν 39% 29% 1 0 + χ˜0π+π0 20% 29% χ˜1π 11% 60% 1 0 + 0 χ˜0π+π0π0 6% 8% χ˜1π π 23% 7% 1 0 + χ˜0π+π+π− 6% 7% χ˜1K 0% 3.5% 1 0 + + − 0 χ˜1π π π π 11% 2.5% Pythia also predicts decay modes not present in Herwig++ that should otherwise be highly suppressed to be fair, Herwig++ hadronization is not doing much better here...

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 14 / 21 Chargino decay modes from Herwig++

Grellscheid, Richardson arXiv:0710.1951

⇒ note that radiative corrections to the mass difference (typically ∼ 200 MeV) will have a profound effect on branching ratios if the tree level difference . 1 GeV

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 15 / 21 Neutralino decays

Decay mode 0 0 χ˜2 → χ˜1 + . . . mh = 124 GeV mh = 127 GeV γ 23.6% 74.0% νν¯ 21.9% 9.7% e+e− 3.7% 1.6% µ+µ− 3.7% 1.5% hadrons 44.9% 12.7% ± χ1 + X 1.9% 0.4%

0 radiative decay to χ˜1γ dominates for small mass differences cleanest experimentally

for mh = 124 GeV scenario hadronic decay modes become important giving low mass jets

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 16 / 21 Measurements at the ILC

+ − 0 0 √ cross sections: χ˜1 χ˜1 , χ˜1χ˜2, s = 350, 500 GeV ⇒ accuracy 1.5%–6% ± 0 mass differences: ∆m(˜χ1 − χ˜1) ⇒ accuracy 20–70 MeV 8

6

GeV 4 ê m d 2

0 2000 4000 6000 8000 10 000

M2 GeV chargino/neutralino masses from recoil against ISR ⇒ accuracy 1.5–3.5 GeV ê ⇒ more details in Hale’s talk

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 17 / 21 Parameter determination

four fitted parameters: ⇒ M1, M2, µ and tan β perform a χ2 fit exp ¯th 2 2 X Oi − Oi χ = exp δO i i tan β remains unconstrained, will be varied in [1, 60] range mu constrained by cross sections and absolute masses: +2.1 ⇒ in mh = 124 GeV scenario µ = 167−1.5 GeV ⇒ in mh = 127 GeV scenario µ = 166 ± 1 GeV mass difference between chargino and LSP strongly constraints M1 and M2

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 18 / 21 2 χ contours mh = 124 GeV scenario

L = 500 fb−1 L = 2 ab−1

10 000 5500

8000 5000

6000 2 2 M M 4500 4000

2000 4000

2000 4000 6000 8000 10 000 1500 1600 1700 1800 1900 2000 M1 M1 tan β = 50 tan β = 10 tan β = 1 , , tan β = 50, tan β = 1 errors halved includes ∆m = m 0 − m 0 χ˜2 χ˜1

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 19 / 21 2 χ contours mh = 127 GeV scenario

L = 500 fb−1 L = 2 ab−1

20 000 14 000

15 000 12 000 2 2

M 10 000 M 10 000

8000 5000

6000 5000 10 000 15 000 20 000 5000 10 000 15 000 20 000

M1 M1 tan β = 50, tan β = 5, tan β = 2 tan β = 50 errors halved includes ∆m = m 0 − m 0 χ˜2 χ˜1

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 20 / 21 Summary

0 ± 0 Light higgsinos = near-degenerate χ˜1, χ˜1 , χ˜2 around 100 − 200 GeV Motivated from Motivated from model-building E.g. hybrid gauge-gravity mediation: µ gravity-mediated, soft masses gauge-mediated Higgsinos hard to see: mass degeneracy ⇒ soft decay products Difficult to see at LHC if everything else heavy Good case for linear collider With precise measurements multi-TeV parameters could be resolved Experimental analysis ongoing ⇒ Hale’s talk

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 21 / 21 Cosmology

Gravitino LSP is natural candidate

Gravitinos produced thermally during reheating at large TR:

g~ g~

ψ3/2 ψ3/2

 T  100 GeV  m 2 Ω h2 ≈ 0.21 R g˜ ψ3/2 10 10 GeV m3/2 1 TeV

see e.g. → Bolz, Brandenburg, Buchmuller¨ ’00

10 TR ≈ 10 GeV: Nicely compatible with leptogenesis Right order of magnitude for DM abundance

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 22 / 21 Cosmology

0 Problem: χ1 NLSP long-lived, decays after BBN Energetic decay products destroy nuclei, distorting light element abundances

10 0 10 0

10−2 10−2 Bounds from → Jedamzik ’06: Ω h 2 NLSP relic density vs. lifetime 10−4 10−4 (assuming large hadronic BR) 4 2 3 −6 −6 He, H, He, (Li) 10 10

100 10 2 10 4 10 6 10 8 10 10 10 12 τ [s]

± Higgsino NLSP relic density low: coannihilation with χ1 (recall first spectrum, mχ0 = 137 GeV, m ± = 140 GeV): 1 χ1

2 −3 Ω 0 h = 3 · 10 χ1 . . . but still in conflict with BBN bounds (Small) R-parity violation? Additional entropy production?

Krzysztof Rolbiecki (IFT-CSIC, Madrid) Higgsino LSP ECFA LC2013, 29 May 2013 23 / 21