Michael Kr amer (RWTH Aachen) -...

Bethe Forum on LHC, Dark Matter and Unification, Bonn, November 2011

SUSY fits at the LHC

Michael Krämer (RWTH Aachen)

Work done in collaboration with P. Bechtle, J. Conley, K. Desch, H. Dreiner,L. Glaser, J. Lindert, B. O’Leary, C. Robens, B. Sarrazin, J.Tattersall and P.Wienemann.

See arXiv:1003.2648, arXiv:1102.4693, arXiv:1105.5398, and arXiv:1110.1287.

Supported by:

SFB/TR 9 “Computational Particle Physics”, Helmholtz Alliance “Physics at the Terascale”,

BMBF-Theorie-Verbund, Marie Curie Research Training Network “Heptools”, Graduiertenkolleg

“Elementarteilchenphysik an der TeV-Skala”

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From the motivation for a recent SUSY meeting at ICL:

The non-observation of SUSY-like signatures in the first fb−1

collected by ATLAS and CMS is in tension with the expectedranges of the parameters of constrained SUSY models like theCMSSM/mSUGRA or non-universal Higgs models. If noevidence of a missing energy signature is found by the end ofthe run year 2011, these constrained models will essentially beruled out, while a very large volume of the parameter space ofsimple SUSY will be excluded.

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SUSY searches: past, present, future

I past: EWK & flavour observables, collider limits, ΩDM

I present: ⊕ LHC SUSY and Higgs exclusions

I future: ⊕ LHC discoveries. . .

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Indirect SUSY searches

There is a wealth of precision measurements

from B/K physics, (g − 2), astrophysics (DM) and collider limitswhich show sensitivity to supersymmetry, in particular

I (g − 2)µ

I DM relic abundance

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Indirect SUSY searches: (g − 2)µ

3.6/2.4σ discrepancy between experimental data and SM prediction

Davier, Hoecker, Malaescu, Zhang, arXiv:1010.4180v1

-700 -600 -500 -400 -300 -200 -100 0

aµ – a

µ exp ×

10

–11

BN

L-E

821 2

004

HMNT 07 (e+e

–-based)

JN 09 (e+e

–)

Davier et al. 09/1 (τ-based)

Davier et al. 09/1 (e+e

–)

Davier et al. 09/2 (e+e

– w/ BABAR)

HLMNT 10 (e+e

– w/ BABAR)

DHMZ 10 (τ newest)

DHMZ 10 (e+e

– newest)

BNL-E821 (world average)

–285 ±

51

–299 ±

65

–157 ±

52

–312 ±

51

–255 ±

49

–259 ±

48

–195 ±

54

–287 ±

49

0 ±

63

→ SUSY loops: aSUSYµ ∼ sgn(µ) tanβM−2SUSY

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Dark matter relic abundance ΩDM

ΩDM is too large for large parts of the CMSSM parameter space, specialannihilation mechanisms are needed

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SUSY framework: the constrained MSSM

Indirect SUSY searches are often interpreted in the constrained MSSM,

where the breaking is universal at the GUT scale

I universal scalar masses: M2Q̃

, M2Ũ

, M2D̃

, M2L̃, M2

Ẽ→ M20 at MGUT

I universal gaugino masses: M1, M2, M3 → M1/2 at MGUTI universal trilinear couplings Aeij ,A

dij ,A

uij → A · heij ,A · hdij ,A · huij at MGUT

In addition we have tanβ, and we fix sign(µ) = +

In the CMSSM the sparticle masses are strongly correlated, e.g.

Mg̃ ' 3Mχ̃± ' 3Mχ̃02 ' 6Mχ̃01and

m2ũL ' M20 + 6.3 M21/2 + DũLm2ẽL ' M20 + 0.5 M21/2 + DẽL

where Df̃L = M2Z cos(2β)(T3f − Qf sin(2θW ))

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The Fittino CMSSM fits

I For the calculation of non-LHC observables we have used

– the spectrum generator SPheno;

– the Mastercode compilation for (g − 2)µ, flavour and electroweakprecision observables;

– MicrOMEGAs for the DM relic densities;

– HiggsBounds for the Higgs limits.

I We require that χ̃01 is the LSP.

I We then calculate and minimize

χ2 = (~Oobs − ~Oth(~P))T cov−1M (~Oobs − ~Oth(~P)) + limits

for each point ~P in the CMSSM parameter space using the Fittinopackage.

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The Fittino CMSSM fits

Our best fit point without LHC exclusions. . .

0h 0A 0H +H10χ

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Mass Spectrum of SUSY Particles no LHC

Environmentσ1

Environmentσ2

Best Fit Value

Mass Spectrum of SUSY Particles no LHC

. . . points to a light sparticle spectrum with m̃ < 1 TeV

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SUSY particle production at the LHC

SUSY particles would be produced at the LHC via QCD processes

[Beenakker, Brensing, MK, Laenen, Kulesza, Niessen ’09]

q̃g̃

q̃q̃

q̃¯̃q

g̃g̃

mq̃ = mg̃

NLO+NLL

√s = 7TeV;

σ (pp → g̃g̃/q̃¯̃q/q̃q̃/q̃g̃ + X) [pb]

m [GeV]12001000800600400200

1000

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10

1

0.1

0.01

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→ σ ≈ 100 fb for m ≈ 1000 GeV at√

S = 7 TeV

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SUSY particle production at the LHC

SUSY particles would be produced at the LHC via QCD processes

[Beenakker, Brensing, MK, Laenen, Kulesza, Niessen ’09]

q̃g̃

q̃q̃

q̃¯̃q

g̃g̃

mq̃ = mg̃

NLO+NLL

√s = 14TeV;

σ (pp → g̃g̃/q̃¯̃q/q̃q̃/q̃g̃ + X) [pb]

m [GeV]30002500200015001000500

103

101

10

1

10−1

10−2

10−3

10−4

10−5

→ σ ≈ 2.5 pb for m ≈ 1000 GeV at√

S = 14 TeV

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SUSY searches at hadron colliders

Powerful MSSM signature at the LHC: cascade decays with ET,miss

Generic signature for many new physics models which address

– the hierarchy problem– the origin of dark matter

→ predict spectrum of new particles at the TeV-scalewith weakly interacting & stable particle (← discrete parity)

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Squark and gluino searches at the LHC

ATLAS limits (1 fb−1)

→ mq̃ ≈ mg̃ ∼> 980 GeV15 / 63

Squark and gluino searches at the LHC

CMS limits (1 fb−1)

)2 (GeV/c0m0 200 400 600 800 1000

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(500)GeVg~

(750)GeVq~

(750)GeVg~

(1000)GeVq~

(1000)GeVg~

(1250)GeVq~

(1250)GeVg~

Tα

Jets+MHT

SS Dilepton

OS Dilepton

MT21 Lepton

-1 = 7 TeV, Ldt = 1.1 fbs ∫CMS Preliminary

> 0µ = 0, 0

= 10, Aβtan

Direct SUSY searches at the LHC: expected limits

The LHC is probing the preferred region of SUSY parameter spaceBechtle, Desch, Dreiner, MK, O’Leary, Robens, Sarrazin, Wienemann, arXiv:1102.4693 [hep-ph]

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2D 95% CL no LHC1D 68% CL no LHC

-195% CL exclusion 35pb-195% CL exclusion 1fb-195% CL exclusion 2fb-195% CL exclusion 7fb

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But what if we do not see any SUSY signal at the LHC?Bechtle, Desch, Dreiner, MK, O’Leary, Robens, Sarrazin, Wienemann, arXiv:1102.4693 [hep-ph]

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2D 95% CL no LHC1D 68% CL no LHC

-195% CL exclusion 35pb-195% CL exclusion 1fb-195% CL exclusion 2fb-195% CL exclusion 7fb

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We have considered the SUSY search in the 4 jets + ET ,miss signature

with Meff =∑

i pT ,i + ET ,miss:

ATL-PHYS-PUB-2010-10

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I We have calculated the CMSSM signal for a grid in (m0,m1/2) using

– the spectrum generator SPheno;

– the MC generator Herwig++;

– NLO+NLL K-factors;

– the fast detector simulation Delphes.

I We consider ten bins in the range 0 < Meff < 4 TeV and calculate theχ2 from the number of signal and background events in each bin ofthe Meff distribution.

I The SM background is taken from the ATLAS simulation. We assign30% systematic uncertainty to the SUSY signal cross-section, and 20%systematic uncertainty to the background.

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We find good agreement with the ATLAS simulation:

FITTINO 4 jets 0 lepton LO

FITTINO 4 jets 0 lepton NLO

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The 4 jets +ET ,miss signature is rather independent of tanβ and A0:

[GeV]effM0 500 1000 1500 2000 2500 3000 3500 4000

-110

1

10

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310

SM=0

0=10, Aβtan

=10000

=10, Aβtan =1000

0=20, Aβtan

=10000

=30, Aβtan =1000

0=40, Aβtan

=10000

=50, Aβtan

[GeV]effM0 500 1000 1500 2000 2500 3000 3500 4000

-110

1

10

210

310

= 5001/2

= 500, M0M

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Global SUSY fits with projected LHC exclusions: results

Low-energy observables, DM, no LHC exclusions

[GeV]0M100 200 300 400 500 600 700 800

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eV]

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2D 95% CL no LHC

1D 68% CL no LHC

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Low-energy observables, DM and LHC exclusions with 1 fb−1

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-12D 95% CL 1fb-11D 68% CL 1fb

-195% CL exclusion 1fb

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2200-12D 95% CL 2fb-11D 68% CL 2fb


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2200-12D 95% CL 7fb-11D 68% CL 7fb


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Global SUSY fits with projected LHC exclusions: is there a tension?

→ LEOs prefer low mass scales (for non-coloured sector)→ LHC prefers high mass scales (for coloured sector)

Is there a tension building up?

Let us look at the best fit points:

M0 M1/2 A0 tanβ χ2/ndf

no LHC 77+114−31 333+89−87 426

+70−735 13

+10−8 19/20

35 pb−1 126+189−54 400+109−40 724

+722−780 17

+14−9 20/21

1 fb−1 235+389−103 601+148−63 627

+1249−717 31

+19−18 24/21

2 fb−1 254+456−128 647+157−74 771

+1254−879 30

+20−19 24/21

7 fb−1 403+436−281 744+142−150 781

+1474−918 43

+11−33 25/21

→ even the CMSSM would ”survive” the 2011/2012 LHC run

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Global SUSY fits with projected LHC exclusions: is there a tension?

P-v

alu

e @

bes

t fi

t p

oin

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-11D 68% CL 7fb-11D 68% CL 2fb-11D 68% CL 1fb

-11D 68% CL 35pb1D 68% CL no LHC

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Why do tan β and M1/2 move to larger values?

I mainly due to aSUSYµ ∼ sgn(µ) tanβM−2SUSY and ΩDM

I ΩDM is too large for large parts of the CMSSM parameter space,special annihilation mechanisms are needed

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Global SUSY fits with projected LHC exclusions: individual pulls

no LHC

σ|Meas.-Fit|/ 0 1 2 3

2hCDMΩ 0.0135 ±0.1099 0.1125

SMµ - aµa-10 10× 9.0) ±(30.2 -10 10×24.0

)K∈C( 0.14 ±0.92 1.03

) ν l→(KBR 0.014 ±1.008 1.000

)γ s→(bBR 0.122 ±1.117 1.022

)ντ →(bBR 0.40 ±1.15 0.96

ll)s X→s(BBR 0.32 ±0.99 0.99

Bsm∆ 0.32 ±1.11 1.03

Bdm∆/Bsm∆ 0.16 ±1.09 1.00

[MeV] ZΓ 2.5 ±2495.2 2495.3

[nb]0hadσ 0.037 ±41.540 41.484

0lR 0.025 ±20.767 20.743

0bR 0.00066 ±0.21629 0.21601

0cR 0.0030 ±0.1721 0.1722

lA 0.0021 ±0.1513 0.1482

τA 0.0032 ±0.1465 0.1482

bA 0.020 ±0.923 0.935

cA 0.027 ±0.670 0.668

FB0,l

A 0.0010 ±0.0171 0.0165

FB0,b

A 0.0016 ±0.0992 0.1039

FB0,c

A 0.0035 ±0.0707 0.0743 leffθ

2sin 0.0012 ±0.2324 0.2314

[GeV] Wm 0.027 ±80.398 80.385

[GeV] > hm 114.3 113.4

no LHC

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-135 pb

σ|Meas.-Fit|/ 0 1 2 3

2hCDMΩ 0.0135 ±0.1099 0.1107

SMµ - aµa-10 10× 9.0) ±(30.2 -10 10×21.4

)K∈C( 0.14 ±0.92 1.02

) ν l→(KBR 0.014 ±1.008 1.000

)γ s→(bBR 0.122 ±1.117 1.009

)ντ →(bBR 0.40 ±1.15 0.945

ll)s X→s(BBR 0.32 ±0.99 0.99

Bsm∆ 0.32 ±1.11 1.02

Bdm∆/Bsm∆ 0.16 ±1.09 1.00

[MeV] ZΓ 2.5 ±2495.2 2495.0

[nb]0hadσ 0.037 ±41.540 41.483

0lR 0.025 ±20.767 20.743

0bR 0.00066 ±0.21629 0.21600

0cR 0.0030 ±0.1721 0.1722

lA 0.0021 ±0.1513 0.1479

τA 0.0032 ±0.1465 0.1479

bA 0.020 ±0.923 0.935

cA 0.027 ±0.670 0.668

FB0,l

A 0.0010 ±0.0171 0.0164

FB0,b

A 0.0016 ±0.0992 0.1037

FB0,c

A 0.0035 ±0.0707 0.0741 leffθ

2sin 0.0012 ±0.2324 0.2314

[GeV] Wm 0.027 ±80.398 80.377

LHC

-135 pb

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-11 fb

σ|Meas.-Fit|/ 0 1 2 3

2hCDMΩ 0.0135 ±0.1099 0.1063

SMµ - aµa-10 10× 9.0) ±(30.2 -10 10×26.3

)K∈C( 0.14 ±0.92 1.01

) ν l→(KBR 0.014 ±1.008 0.999

)γ s→(bBR 0.122 ±1.117 0.952

)ντ →(bBR 0.40 ±1.15 0.91

ll)s X→s(BBR 0.32 ±0.99 0.99

Bsm∆ 0.32 ±1.11 1.01

Bdm∆/Bsm∆ 0.16 ±1.09 1.00

[MeV] ZΓ 2.5 ±2495.2 2494.9

[nb]0hadσ 0.037 ±41.540 41.482

0lR 0.025 ±20.767 20.741

0bR 0.00066 ±0.21629 0.21596

0cR 0.0030 ±0.1721 0.1722

lA 0.0021 ±0.1513 0.1476

τA 0.0032 ±0.1465 0.1476

bA 0.020 ±0.923 0.935

cA 0.027 ±0.670 0.668

FB0,l

A 0.0010 ±0.0171 0.0163

FB0,b

A 0.0016 ±0.0992 0.1035

FB0,c

A 0.0035 ±0.0707 0.0739 leffθ

2sin 0.0012 ±0.2324 0.2315

[GeV] Wm 0.027 ±80.398 80.368

LHC

-11 fb

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-12 fb

σ|Meas.-Fit|/ 0 1 2 3

2hCDMΩ 0.0135 ±0.1099 0.1134

SMµ - aµa-10 10× 9.0) ±(30.2 -10 10×13.7

)K∈C( 0.14 ±0.92 1.01

) ν l→(KBR 0.014 ±1.008 0.999

)γ s→(bBR 0.122 ±1.117 0.971

)ντ →(bBR 0.40 ±1.15 0.913

ll)s X→s(BBR 0.32 ±0.99 1.00

Bsm∆ 0.32 ±1.11 1.01

Bdm∆/Bsm∆ 0.16 ±1.09 1.00

[MeV] ZΓ 2.5 ±2495.2 2494.4

[nb]0hadσ 0.037 ±41.540 41.482

0lR 0.025 ±20.767 20.741

0bR 0.00066 ±0.21629 0.21596

0cR 0.0030 ±0.1721 0.1722

lA 0.0021 ±0.1513 0.1473

τA 0.0032 ±0.1465 0.1473

bA 0.020 ±0.923 0.935

cA 0.027 ±0.670 0.668

FB0,l

A 0.0010 ±0.0171 0.0163

FB0,b

A 0.0016 ±0.0992 0.1033

FB0,c

A 0.0035 ±0.0707 0.0738 leffθ

2sin 0.0012 ±0.2324 0.2315

[GeV] Wm 0.027 ±80.398 80.366

LHC

-12 fb

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-17 fb

σ|Meas.-Fit|/ 0 1 2 3

2hCDMΩ 0.0135 ±0.1099 0.1095

SMµ - aµa-10 10× 9.0) ±(30.2 -10 10×13.3

)K∈C( 0.14 ±0.92 1.01

) ν l→(KBR 0.014 ±1.008 0.999

)γ s→(bBR 0.122 ±1.117 0.948

)ντ →(bBR 0.40 ±1.15 0.854

ll)s X→s(BBR 0.32 ±0.99 1.00

Bsm∆ 0.32 ±1.11 1.00

Bdm∆/Bsm∆ 0.16 ±1.09 1.00

[MeV] ZΓ 2.5 ±2495.2 2494.5

[nb]0hadσ 0.037 ±41.540 41.482

0lR 0.025 ±20.767 20.741

0bR 0.00066 ±0.21629 0.21595

0cR 0.0030 ±0.1721 0.1722

lA 0.0021 ±0.1513 0.1473

τA 0.0032 ±0.1465 0.1473

bA 0.020 ±0.923 0.935

cA 0.027 ±0.670 0.668

FB0,l

A 0.0010 ±0.0171 0.0163

FB0,b

A 0.0016 ±0.0992 0.1033

FB0,c

A 0.0035 ±0.0707 0.0738 leffθ

2sin 0.0012 ±0.2324 0.2315

[GeV] Wm 0.027 ±80.398 80.365

LHC

-17 fb

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Global SUSY fits with projected LHC exclusions: mass spectrum


0h 0A 0H +H10χ

20χ

30χ

40χ

1+χ

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Rl~

Ll~

1τ∼

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-1 Mass Spectrum of SUSY Particles 1fb Environmentσ1

Environmentσ2

Best Fit Value

-1 Mass Spectrum of SUSY Particles 1fb

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0h 0A 0H +H10χ

20χ

30χ

40χ

1+χ

2+χ

Rl~

Ll~

1τ∼

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Best Fit Value


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0h 0A 0H +H10χ

20χ

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Best Fit Value


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What is the role of the Higgs sector?

A few comments:

I the Higgs sector is strongly constrained in the CMSSM;

I in our CMSSM fits, the light Higgs is very SM-like, and the heavyHiggses are beyond current (future?) reach;

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A few more comments:

I the Higgs sector is strongly constrained in the CMSSM;

I in our CMSSM fits, the light Higgs is very SM-like, and the heavyHiggses are beyond current (future?) reach;

I the exclusion of a Higgs with mh ∼< 140 GeV would probably be theonly way to exclude the MSSM;

I SM Higgs searches may, however, not be sufficient to exclude a lightMSSM Higgs, e.g. because of invisible decays h→ χ̃χ̃;

I the Higgs sector will play a crucial role for the assessment of SUSYin the near future!

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Future SUSY searches beyond MET

I flavour constraints, e.g. Bs → µµ (LHCb)

I direct dark matter searches (see e.g. Aprile et al: arXiv:1104.2549)

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Comparison of global CMSSM fits with and without LHC exclusions

There has been a lot of activity recently (see e.g. arXiv:1109.3859v1)

]2 [GeV/c0m0 100 200 300 400 500 600 700 800 900 1000

]2 [

GeV

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tαAllanach CMS -1Allanach 35pb

-1Bertone 35pb-1Farina 1fb

Fittino pre LHC-1Fittino 35pb

-1Fittino 1fb-1Fittino 2fb-1Fittino 7fb

MC pre LHC

tαMC CMS -1MC 35pb

-1MC 1fbSuperBayes pre LHC

→ there is less agreement after the inclusion of LHC limits

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Comparison of global CMSSM fits with and without LHC exclusions

There has been a lot of activity recently (see e.g. arXiv:1109.3859v1)

]2 [GeV/c1/2m0 100 200 300 400 500 600 700 800 900 1000

)βta

n(

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tαAllanach CMS -1Allanach 35pb

-1Bertone 35pb-1Farina 1fb

Fittino pre LHC-1Fittino 35pb

-1Fittino 1fb-1Fittino 2fb-1Fittino 7fb

MC pre LHC

tαMC CMS -1MC 35pb

-1MC 1fbSuperBayes pre LHC

→ there is less agreement after the inclusion of LHC limits

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Global SUSY fits: the χ2 of the LHC exclusions

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Let us look at the χ2 of the LHC exclusions along the red line:

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We find a non-trivial shape of the LHC χ2:

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20.95z

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When we vary m0 and m1/2, both the SUSY rate as well as the shape ofthe Meff distribution change; SUSY signals with larger rate may becomemore background-like and thus harder to observe.

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=10000

=10, Aβtan =1000

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=10000

=30, Aβtan =1000

0=40, Aβtan

=10000

=50, Aβtan

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= 5001/2

= 500, M0M

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When we vary m0 and m1/2, both the SUSY rate as well as the shape ofthe Meff distribution change; SUSY signals with larger rate may becomemore background-like and thus harder to observe.

[GeV]effM0 500 1000 1500 2000 2500 3000 3500 4000

-110

1

10

210

310

SM=0

0=10, Aβtan

=00

=30, Aβtan =0

0=50, Aβtan

=10000

=10, Aβtan =1000

0=30, Aβtan

[GeV]effM0 500 1000 1500 2000 2500 3000 3500 4000

-110

1

10

210

310

= 4001/2

= 200, M0M

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Comparison of global CMSSM fits with LHC exclusions

I There is too wide a spread in global CMSSM fits with LHC exclusions.

The different groups use different

I LHC signatures;

I levels of sophistication in the implementation of LHC limits.

We should compare the LHC χ2 maps between the different groupsand identify problematic regions.

I How can we optimize the LHC sensitivity?

We observe

I a reduced sensitivity when going from our analysis based on the Meffdistribution to the more recent analysis of ATLAS-CONF-2011-086 (prel.);

I limitations of the sensitivity due to the systematic uncertainties of signaland background.

We should compare the impact of different analyses (Meff , αT etc.) onglobal SUSY fits and include a combination of various LHC constraints.

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SUSY parameter determination at the LHC

Mass measurements from cascade decays, e.g.

→ kinematic endpoints sensitive to masses:

(m2ll)max = (m2χ̃02

−m2l̃R )(m2l̃R−m2χ̃01)/m

2l̃R

(m2qll)max = (m2q̃L −m

2χ̃02

)(m2χ̃02−m2χ̃01)/m

2χ̃02

(m2ql,min)max = (m2q̃L −m

2χ̃02

)(m2χ̃02−m2l̃R )/m

2χ̃02

(m2ql,max)max = (m2q̃L −m

2χ̃02

)(m2l̃R −m2χ̃01

)/m2l̃R

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SUSY parameter determination with cross sections

How well could we do at 7 TeV and 1 fb−1? [Dreiner, MK, Lindert, O’Leary]

[cf. Baer et al., Altunkaynak et al., . . . ]

0

2

4

6

8

10

12

14

16

18

20

(GeV)1/2M150 200 250 300 350

(G

eV)

0M

20

40

60

80

100

120

140

160

SPS1a with 4 kinematic edges only

→ no stable fit→ add cross sections:

sensitive to masses and spins

0

2

4

6

8

10

12

14

16

18

20

(GeV)1/2M150 200 250 300 350

(G

eV)

0M

20

40

60

80

100

120

140

160

kinematic edges ⊕ cross sections→ m0 = 99± 9 GeVm1/2 = 250± 7 GeVtanβ = 11± 6

→ cross sections are crucial to determine BSM parameters

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How well could we do at 7 TeV and 1 fb−1? [Dreiner, MK, Lindert, O’Leary]

[cf. Baer et al., Altunkaynak et al., . . . ]

0

2

4

6

8

10

12

14

16

18

20

(GeV)1/2M150 200 250 300 350

(G

eV)

0M

20

40

60

80

100

120

140

160

SPS1a with 4 kinematic edges only

→ no stable fit→ add cross sections:

sensitive to masses and spins

0

2

4

6

8

10

12

14

16

18

20

(GeV)1/2M150 200 250 300 350

(G

eV)

0M

20

40

60

80

100

120

140

160

kinematic edges ⊕ cross sections→ m0 = 99± 9 GeVm1/2 = 250± 7 GeVtanβ = 11± 6

→ cross sections are crucial to determine BSM parameters61 / 63


Beyond mSUGRA: explore mirage mediation models[Choi, Nilles, Falkowski, Ratz, Loewen and many others]

→ characteristic pattern of soft SUSY-breaking termsM1 : M2 : M3 ' (1 + 0.66α) : (2 + 0.2α) : (6− 1.8α)

→ relative size of modulus and anomaly mediation controlled by αHow well can we determine α from future LHC data?

Assume LHC @ 14 TeV with 1 fb−1

kinematic edges only

[Conley, Dreiner, Glaser, MK, Tattersall]

kinematic edges ⊕ cross sections→ α = 5± 0.3

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Michael Kr amer (RWTH Aachen) -...

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