SUSY Search at Future Collider and Dark Matter Experiments

D. P. RoyHomi Bhabha Centre for Science Education

Tata Institute of Fundamental ResearchMumbai – 400088, India

&Instituto de Fisica Corpuscular, CSIC-U. de Valencia

Valencia, Spain

Outline

• SUSY : Merits & Problems

• Nature of LSP : Bino, Higgsino or Wino

• DM Constraints on Bino, Higgsino & Wino LSP Scenarios ( mSUGRA & mAMSB Models)

• Bino LSP Signals at LHC

• Higgsino & Wino LSP Signals at CLIC

• Bino, Higgsino & Wino LSP Signals in DM Expts

• Nonminimal Models for Higgsino, Wino & Bino LSP

WHY SUSY :

A. Natural Soln to the Hierarchy Problem of EWSB

B. Natural (Radiative) Mechanism for EWSB

C. Natural Candidate for the cold DM (LSP)

D. Unification of Gauge Couplings @ GUT Scale

PROBLEMS WITH SUSY :

1. Little Hierarchy Problem 2. Flavour & CP Viol. Problem

-h

t t~

mh > 114 GeV (LEP) m > 1 TeVt~

γ

eμ

e,~

e e

γe~

0de

)(

10

~~

~,

e

e

mm

TeVm

)10(

102

,

~

A

e TeVm

Split SUSY solves 2 at the cost of aggravating1.

DCTeVm

BANoTeVm

o

f

&1

)&(1

,

~

We shall consider a moremoderate option, allowing

TeVmf

10010~

Nature of the Lightest Superparticle (LSP) in the MSSM:

Astrophysical Constraints Colourless & Chargeless LSPDirect DM Detection Expts LSP not Sneutrino

ud HcHcWcBcLSP~~~~

432101

Diagonal elements : M1, M 2, ±μ in the basis ud HHHWB~~~

&~

,~

2,1

Nondiagonal elements < MZ

Exptl Indications M1, M 2, μ > 2MZ in mSUGRA HorWB~~

,~

Exception : Mii ≈ Mjj tan 2θij = 2Mij / (Mii – Mjj) large HWHB~~

,~~

“Well-tempered Neutralino Scenario” Arkani-Hamed, Delgado & Giudice

DM Relic Density Constraints on Bino, Higgsino & Wino LSP Scenarios

mSUGRA: SUSY Br in HS communicated to the OS via grav. Int. m0 , m ½ , tanβ, A0 , sign (μ) at GUT scale ( A0 = 0 & +ve μ)

RGE ( Weak Sc masses)

2/12/1222/12/111 8.0)/(:~

&4.0)/(:~

mmMWmmMB GG

||

2

2/1

2

2201

2

22

22222

)tan,,()tan,,(

5tan@1tan

tan2/

mhCmhCM

MMM

MEWSB

titiHu

HuHuHd

Z

RGE:

Hyperbolic Br (tan β > 5) of μ 2 :

Imp Weak Sc Scalar mass MHu

(LEP)

LSPHMmm

LSPBMmm

~

~

12/10

12/10

Chattopadhyay et alm0 ~ m1/2 TeV (Bino LSP)

mh > 115 GeV m1/2 > 400 GeV (M1>2MZ)

also large sfermion mass

Bino does not carry any gauge charge Pair annihilate via sfermion exch

B~

B~

f~

f

f

Large sfermion mass too large Ωh2

Except for the stau co-ann. region

Bmm ~~

B~

~

FP

CA ~

LSPH ~

Anns.Re

%)10(:~1~ withinMmCoAnn 12:.Re MMAnns A

)~~

(: 1 HBMPtFocus

Zf

f

)7(

1:~

0

~ 0,

TeVmm

TeVMLSPHH

f

fH~

0~H

W

4,32,1

24

23

, ccgg

ccg

HA

Z

f

fA

ud HcHcWcBc~~~~

4321

Wino LSP (mAMSB model)

SUSY braking in HS in communicated to the OS via the Super-Weyl Anomaly Cont. (Loop)

20

22/3

22/3

2/32

23

32/32

22

22/32

21

12/3

4

1&

163,

16,

165

33

mmyg

mmy

A

mg

Mmg

Mmg

Mmg

M

ygy

y

g

m3/2 , m0 , tan β, sign (μ)

RGE M1 : M2 : |M3| ≈ 2.8 : 1 : 7.1 including 2-loop conts

)3010(1:~

&2.01.2:~

2 TeVmTeVLSPHTeVMLSPW

Chattopadhyay et al

)~

(~ 00 HW

)~

(~ 00 HW

)~

(~ HW

W

W

)~

(~ HW

)~

(~ 00 HW

W

f

f

Robust results, independent of other SUSY parameters(Valid in any SUSY model with Wino(Higgsino) LSP)

Bino LSP Signal at LHC :

TT jjjjqqqqggjjqqqq ~~;~~

Canonical Multijet + Missing-ET signal with possibly additional jets (leptons) from cascade decay (Valid through out the Bino LSP parameter space, including the Res.Ann Region)

Focus Point Region:

12/10

2222/1

20

22/1

2

220

3/2

20

2 2/2)2/3(

Msmallmm

MmmmCmymM ZtHu

T

jit

dutg

dutt

leptonsWbgg

Wbbtttg

TeVmTeVmTeVm

TeVmTeVm

CmmmCmmCmmymm

)(44~~...22,~

2.2,5.1,3.1

10tan&5.0,2

;)3/1(

0~

~,~~~

2/10

22/1

20

2~

,~2

2/120

22/1

20

3/2

20

2~

1

1

1

Inverted Hierarchy

Chattopadhyay et al ljetsb T )41(4 Focus Pt SUSYSignal at LHC

Guchait & Roy

μ >0

μ<0

~ Co-annihilation region

111

~

~,~1

mm

BR ≈ 1 BR = 1

τ is soft, but Pτ≈+1

One can use Pτ to detect the Soft τ coming from

.~1

111

~,

~ZW

:0jet

s

1-prong hadronic τ decay (BR≈0.5)

jetp

pR

With pT > 20 GeV cut for the τ-jet the τ misid. Probabilityfrom QCD jets goes down from 6% for R > 0.3 (pTπ±> 6 GeV) to 0.25% for R > 0.8 (pTπ± > 16 GeV), while retaining mostOf the signal.

Higgsino & Wino LSP Signals at CLIC:

)~

(~

)2.0(10; 0, WHGeVmmmqq Z

π± are too soft to detect at LHC without any effective tagMust go to an e+e- Collider with reqd. beam energy (CLIC)

W,Be+

e-

γ

χ+

χ-

e+

e-

γ

W

ν

νChen, Drees, Gunion

OPAL (LEP) )~

&~

(90 WHGeVm

msEsM rec 2)/21(,10 2/1

)2(1)100(50sin: min

3

min GeVEsEeeee T

TeVT

Δm < 1 GeV χ± and /or decay π± track with displaced vertex in MVX

Δm > 1 GeV 2 prompt π± tracks (Used by OPAL to beat ννγ background)

χ± decay tracks :

Chottopadhyay et al

Higgsino LSP Signal at 3 TeV CLIC : mχ = μ ≈ 1 TeV

Luminosity = 103 ev/fb

W,Be+

e-

γ

χ+

χ-

e+

e-

γ

W

ν

ν

# ev

106

103

)(1&50

1

1&1000

1

LEPB

S

B

S

B

S

B

S

(χ± decay π± tracks)

Polarized e- (80% R) & e+ (60% L) beams :

)%25(Pr%2 dUnpolarizeobabilityee RL

Suppression of Bg by 0.08 & Sig by 0.8 Increase of S/B by ~ 10

# ev

102

104

3&50

1100

B

S

B

SGeVET

Prompt π± tracks in the Background from Beamstrahlung

W,Be+

e-

γ

χ+

χ-

χ π+

χ π-

γ

W

ν

ν

e-

e+

γ

γ

Beamstrahlung Bg f ≈ 0.1: 103 fB

S

B

S

π+

π-

Size of fB present for Mrec < 2 TeV Estimate of fB for Mrec > 2 TeV

Any Excess over this Estimate χ signal & χ mass

Δm = 165 – 190 MeV for M2 ≈ 2 TeV & μ > M2

cτ = 3-7 cm (SLD MVX at 2.5 cm 2 cm at future LC)Tracks of as 2 heavily ionising particles along with their decay π± tracks.

W~

Wino LSP Signal at 5 TeV CLIC : mχ = M2 ≈ 2 TeV

We+

e-

γ

χ+

χ-

χ π+

χ π-

e+

e-

γ

W

ν

ν

Both Wino Signal and Neutrino Bg couple only to e-L & e+

R.

One can not suppress Bg with polarized beams. But one can use polarized beams to increase both Signal and Bg rates.

Polarized e-L (80%) & e+

R (60%) Probability of e-Le+

R = 72% (25% Unpolarized) Increase of Signal and Bg rates by factors of 72/25 ≈ 3.

Bg effectively suppressed due to a robust prediction of charged and neutral wino mas diff. Δm

W~ W

~W

~

γ, Z

Discovery potential is primarily determined by the number of Signal events.

103

102

# ev

Sig ~ 100 (300) events withUnpolarized (polarized) beams

The recoiling mass Mrec > 2mχ

helps to distinguish Sig from Bg& to estimate mχ .

Bino, Higgsino & Wino LSP Signals in Dark Matter Detection Expts

χ

χ

1. Direct Detection (CDMS, ZEPLIN…)

Ge

H

Spin ind.

Ge

ud HcHcWcBc~~~~

4321

4,32,124

23 & ccgccg HZ

Best suited for Focus pt. region Less for co-ann & res.ann regions B

HB~

~~

~

Unsuited for (Suppressed both by Hχχ coupling and large χ mass)WH~

&~

2. Indirect Detection via HE ν from χχ annihilation in the Sun (Ice Cube,Antares)

χ

χ

p

p

Z

Spin dep.

ud

Zptrapann

HHHWBfor

PtFocHBmixedOKfor

ccgRR

~~~&

~,

~0

.)~~

(

)( 224

23

2.

3. Detection of HE γ Rays from Galactic Centre in ACT (HESS,CANGAROO,MAGIC,VERITAS) WH

~&

~

χ

χ

χ+

W

W

χ

χ

χ+

Wπ0sγs vσWW ~ 10-26 cm3/sCont. γ Ray Signal(But too large π0γ from Cosmic Rays)

W

W

W

γ

γ(Z)

vσγγ~ vσγZ ~ 10-27-10-28 cm3/sDiscrete γ Ray Line Signal (Eγ ≈ m χ) (Small but Clean)

γ flux coming from an angle ψ wrt Galactic Centre

LS

LS densityDMenergy

kpccmGeVdllJ

srscmJmTeVscmvN

ZNdllm

vN

]5.8)/3.0/[()()(

)()/1)(10/(1087.1)(

)(1),(2;)()(4

)(

232

1122132814

22

∫ΔΩ=0.001srJ(0)dΩ ≈ 1 sr (Cuspy:NFW), 103 (Spiked), 10-3 (Core)

∫ΔΩ=0.001srγ dΩ (NFW)

Discovery limit of ACT

Chattopadhyay et al

mSUGRA

mAMSB

)()(001.0

NFWd

Discovery limit of ACT

Chattopadhyay et al

W~

H~

HESS has reported TeV range γ rays from GC. But with power law energy spec SNR Formidable Bg to DM Signal.The source could be GC (Sgr A*) or the nearby SNR (Sgr A east) within its ang. res. Better energy & angular resolution to extract DM Signal from this Bg.

Higgsino, Wino & Bino LSP in nonminimal SUSY modelsH~

LSP in SUGRA models with nonuniversal 1)scalar & 2)gaugino masses

LSPH

mmMMmmmmBut

mmMMmmmmm

MmCmymm

ZHu

ZtHu

ZttHuHu

~@2/223:

@2/2

2/2

3

2/101222

2/120

20

20

2/101222

2/120

20

2~0

20

2222/1

2

22~0

3/2

20

2

1)

J.Ellis et al,….

2)

LSPH

MCmMF

mmMCUniversalmMF

FSU

jiM

FMM

GS

GS

S

jiPl

ijS

iGi

~4.1)1,2,10(200

@2)(1

200752412424:)5(

3,2,1&;

122/13,2,1

2/10122/13,2,1

Chattopadhyay & Roy,….

Wino LSP in 1)Nonminimal AMSB & 2)String models

1) Tree level SUSY breaking contributions to gaugino and scalar masses

).(@0:

@0)2424(1

*;2

2

ionConsideratSymmleveltreemBut

leveltreeMForF

M

FFm

M

FM

SS

Pl

SS

Pl

S

†

m (tree) ~ 100 Mλ (AMSB) Giudice et al, Wells

2) String Th: Tree level SUSY breaking masses come only from Dilaton field, while they receive only one-loop contributions from Modulii fields.

Assuming SUSY breaking by a Modulus field Mλ & m2 at one-loop level

M2 < M1 < M3 similar to the AMSB ( Wino LSP) & m ~ 10 Mλ

Brignole, Ibanez & Munoz ‘94

TeVmTeVMW

21~ 102 In these models:

Bino LSP in Non-universalGaugino Mass Model

M3 = 300, 400, 500 & 600 GeV

King, Roberts & Roy 07

Bulk annihilation region ofBino DM (yellow) allowed in Non-universal gaugino massmodels

Light right sleptonsEven left sleptons lighter than Wino=>Large leptonic BR of SUSYCascade deacy via Wino