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 & BinoLSP

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

−χ

e,

~µν

e e

γe~

0χde

)(

10

~~

~,

e

e

mm

TeVm

νν

ν

µ

µ

≅

>)10(

10

2

,

~

−<

>

A

e TeVm

µφSplit SUSY solves 2 at the cost of

aggravating1.

DCTeVm

BANoTeVm

o

f

&1

)&(1

,

~

⇒≈

⇒>>>

±χ

We shall consider a more

moderate option, allowing

TeVmf

10010~ −=

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

Astrophysical Constraints ⇒ Colourless & Chargeless LSP

Direct DM Detection Expts ⇒ LSP not Sneutrino

ud HcHcWcBcLSP~~~~

4321

0

1 +++=≡→∴ χχ

Diagonal elements : M1, M 2, ±µ in the basisud HHHWB

~~~&

~,

~2,1 ±=

Nondiagonal elements < MZ

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

,~

≅⇒ χ

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

,~~

−−=⇒ χ“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 ≈=≈= αααα

||

2

2/1

2

2

2

01

2

2

2

22222

)tan,,()tan,,(

5tan@1tan

tan2/

mhCmhCM

MMM

MEWSB

titiHu

HuHuHd

Z

βαβα

ββ

βµ

ε ≈−

+=−

>−≈−

−=+⇒

RGE:

Hyperbolic Br (tan β > 5) of µ 2 :

Imp Weak Sc Scalar mass MHu

(LEP)

LSPHMmm

LSPBMmm

−⇒<⇒>>

−⇒>⇒≈~

~

12/10

12/10

µ

µ

Chattopadhyay et al

m0 ~ 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 ~~ ≅τ

B~

τ~ τττ

γ

FP→

CA−↑τ~

LSPH −←~

Anns.Re↑

%)10(:~1~ ≈≅− withinMmCoAnn ττ 12:.Re MMAnns A ≅

)~~

(: 1 HBMPtFocus −=≅− χµχ

χZ

f

f

)7(

1:~

0

~ 0,

TeVmm

TeVMLSPHH

>≈

≅≅− ±

φ

µ

f

f±H~

0~H

W

4,32,1

2

4

2

3

, ccgg

ccg

HA

Z

∝

−∝

χχχχ

χχ

f

fA

χ

χ

ud HcHcWcBc~~~~

4321 +++=χ

Wino LSP (mAMSB model)

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

2

0

2

2/3

2

2/3

2/32

2

332/32

2

222/32

2

112/3

4

1&

163,

16,

165

33

mmyg

mmy

A

mg

Mmg

Mmg

Mmg

M

yg

y

y

g

+

∂∂

+∂∂

−=−=

−===⇒=

βγ

βγβ

πππ

β

φ

λ

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 −=≅−±=− φµ

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 ∉→→∉→→ χχχχ ~~;~~

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

222

2/1

2

0

2

2/1

2

2

2

0

3/2

2

0

2 2/2)2/3(

Msmallmm

MmmmCmymM ZtHu

≈⇒>>

−−=−+=−−=≈≈

µ

µε

T

ji

t

dutg

dutt

leptonsWbgg

Wbbtttg

TeVmTeVmTeVm

TeVmTeVm

CmmmCmmCmmymm

∉+→+→⇒

→→⇒

≥==⇒

===

+=+=+−=

+

)(44~~

...22,~

2.2,5.1,3.1

10tan&5.0,2

;)3/1(

0~

~,~~~

2/10

2

2/1

2

0

2~

,~2

2/1

2

0

2

2/1

2

0

3/2

2

0

2~

1

1

1

χχχ

βInverted

Hierarchy

Chattopadhyay et al ljetsb T )41(4 −+∉++Focus Pt SUSY

Signal at LHC

Guchait & Roy

µ >0

µ<0

τ~ Co-annihilation region

χτττνχ

χτ

→→

≅±

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 χττ →

χχ ≡≡ ±111

~,

~ZW

:0

321jet

s−

±± →τ

ππντ 1-prong hadronic τ decay (BR≈0.5)

jetp

pR

−

±

=τ

π

With pT > 20 GeV cut for the τ-jet the τ misid. Probability

from 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 most

Of the signal.

Higgsino & Wino LSP Signals at CLIC:

)~

(~

)2.0(10; 0

,WHGeVmmmqq

Z ↵<−≡∆→→ ±−+−+

χχγ χχππχχ

⇒π± are too soft to detect at LHC without any effective tag

⇒Must go to an e+e- Collider with reqd. beam energy (CLIC)

W,Be+

e-

γ

χ+

χ-

e+

e-

γ

W

ν

ν

Chen, Drees, Gunion

OPAL (LEP) )~

&~

(90 WHGeVm >⇒ χ

χγγθ msEsM rec 2)/21(,10 2/1 >−=> o

o)2(1)100(50sin: min

3

min >⇒>⇒≅→ −+−+ θθγ γγθ GeVEsEeeee T

TeV

T

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

∆m > 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

γ

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

∆m = 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. ∆m

±W~ ±

W~

±W~

γ, Z

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

103

102

# ev

Sig ~ 100 (300) events with

Unpolarized (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 +++=χ

4,32,1

2

4

2

3 & ccgccg HZ ∝−∝ χχχχ

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

HB~

~~

≅

−=

χ

χ

τ~

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

&~

≅χ

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

χ

χ

p

p

Z

Spin dep.

ud

Zp

trapann

HHHWBfor

PtFocHBmixedOKfor

ccgRR

~~~&

~,

~0

.)~~

(

)( 22

4

2

3

2.

±≡≅⇒

−=⇒

−∝∝∝=

χ

χ

σ χχχχχχ

3. Detection of HE γ Rays from Galactic Centre in

ACT (HESS,CANGAROO,MAGIC,VERITAS) WH~

&~

≅χ

χ

χ

χ+

W

W

χ

χ

χ+

W→→→→π0s→→→→γs vσWW ~ 10-26 cm3/s

⇒⇒⇒⇒Cont. γ Ray Signal

(But too large π0→→→→γ from Cosmic Rays)

W

W

W

γ

γ(Z)

vσγγ~ vσγZ ~ 10-27-10-28 cm3/s

⇒Discrete 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

2

2

ρψ

ψσψφ

γγγψρπ

σψφ

χγγ

γχ

γγ 321

∫∆Ω=0.001srJ(0)dΩ ≈ 1 sr (Cuspy:NFW),

103 (Spiked), 10-3 (Core)

∫∆Ω=0.001srφφφφγ dΩ (NFW)

←←←←Discovery limit of ACT

Chattopadhyay et al

mSUGRA

mAMSB

)()(001.0

NFWd∫=∆Ω

Ωψφγ

←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 models

H~

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

2/101

222

2/1

2

0

2

0

2

0

2/101

222

2/1

2

0

2

0

2~

0

2

0

222

2/1

2

2

2~

0

3/2

2

0

2

µµ

µµε

µ

1)

J.Ellis et al,….

2)

LSPH

MCmMF

mmMCUniversalmMF

FSU

jiM

FMM

G

S

G

S

S

ji

Pl

ijS

i

G

i

−⇒

<⇒≅⇒×=⇒=

≈>⇒≅⇒=⇒=

+++=⊗⊃

=∈≡

~

4.1)1,2,10(200

@2)(1

200752412424:)5(

3,2,1&;

122/13,2,1

2/10122/13,2,1

µ

µ

λλλ

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

−≠

−=⇒⊄⊗≠

∈∈

φ

λ

φλ φφλλ†

mφ (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 & mφ2 at one-loop level

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

Brignole, Ibanez & Munoz ‘94

TeVmTeVMW

21~ 102 −≈⇒≈ φ

In these models:

Bino LSP in Non-universal

Gaugino Mass Model

M3 = 300, 400, 500 & 600 GeV

King, Roberts & Roy 07

Bulk annihilation region of

Bino DM (yellow) allowed in

Non-universal gaugino mass

models

Light right sleptons

Even left sleptons lighter than Wino

=>Large leptonic BR of SUSY

Cascade deacy via Wino