Probing Supersymmetric Cosmology at the LHC Alfredo Gurrola On behalf of TAMU (full list of collaborators in the slides to follow) Karlsruhe, Germany -

Probing Supersymmetric

Cosmology at the LHC

Probing Supersymmetric

Cosmology at the LHC

Alfredo GurrolaOn behalf of TAMU (full list of collaborators in the slides to follow)

Karlsruhe, Germany - August 19, 2009

Aug. 19, 2009 Probing Supersymmetric Cosmology at the LHC 1

Outline


Motivation

Goals

General approach to extracting Dark Matter relic density

Case studies:

Co-Annihilation

Focus point

Over-dense Dark Matter region

Work in progress

Motivation: Content of the Universe

“Normal” MatterStill Unknown

Does not interact with light (“invisible”)Relic Density: A measure

of the density of dark matter left in the universe


Our main goal is to develop techniques/methods to extract the relic density from measurements at the Large Hadron Collider.

Relic density calculation depends on the particular case of interest:

Goal

3 22eqnnvHn

dt

dn )( 3 22 SnnvHn

dt

dneq

Standard Cosmology Non-Standard Cosmology

[Case 1] “Coannihilation (CA)” RegionArnowitt, Dutta, Gurrola, Kamon, Krislock, Toback, PRL100 (2008) 231802

For earlier studies, see Arnowitt et al., PLB 649 (2007)

73; Arnowitt et al., PLB 639 (2006) 46

[Case 2] “Over-dense” RegionDutta, Gurrola, Kamon, Krislock, Lahanas, Mavromatos, NanopoulosPRD 79 (2009) 055002

[Case 3] “HB/Focus Point” RegionArnowitt, Dutta, Flanagan, Gurrola, Kamon, Kolev, Krislock

Supercritical String

Cosmologye.g., Rolling dilation in Q-cosmology


General Approach We want to take a general approach that is “independent” (to the largest

possible extent) of the particular model or scenario we are targeting:

Measure the global SUSY scale- Allows us to filter out models/scenarios that are not consistent with the global scale

1

Identify smoking-gun variables- e.g. Different points in SUSY parameter space can allow for similar global scales. We need to find the “smoking-gun” variables to discriminate between them

2


General Approach We want to take a general approach that is “independent” (to the largest

possible extent) of the particular model or scenario we are targeting:

Parameterize variables in terms of “physical” values (SUSY masses) & model parameters- The parameterization is done by varying one SUSY mass or model parameter at a time, while keeping other masses/parameter constant

3

Determine SUSY masses4

Determine model parameters- We can also use the determination of the SUSY masses to test e.g. gaugino universality.

5

W ≟ ?6Aug. 19, 2009 Probing Supersymmetric Cosmology at the LHC 6

mSUGRA (Benchmark Scenario)At the Grand Unified Scale:

4 parameters + 1 signm1/2 Common gaugino mass at MG

m0 Common scalar mass at MG

A0 Trilinear couping at MG

tanb <Hu>/<Hd> at the electroweak scale

sign(m) Sign of Higgs mixing parameter (W(2) = m Hu Hd)






Determines the particle masses at the electroweak scale by solving the Renormalization Group Equations


mSUGRA (Benchmark Scenario)At the Grand Unified Scale:











(WMAP3) 129.0094.0

SM fromdeviation 2.3 :)2(

105.4)(102.2

GeV 104 GeV; 114

2~

44

~

01

1

h

~g

sbB

MM Higgs

Key experimentalconstraints

Jegerlehner and Nyffeler,arXiv:0902.3360


Case 1: Co-Annihilation RegionWithin this framework, let’s look at the 1st dark matter allowed

region: Co-Annhilation region

tanb = 40

A0 = 0, m > 0

ab

c

m0 (

GeV

)

m1/2 (GeV)

Coannihilation Region1

Excluded by1)Rare B decay b sg 2)No CDM candidate3)Muon magnetic moment

a

bc


Case 1: Co-Annihilation RegionAt the Grand Unified Scale:












Case 1 benchmark point:

m0 = 210

m1/2 = 350

tanb = 40

A0 = 0

sign(m)>0

GeVM

GeVM

GeVM

GeVM g

6.10

141

260

831

01

02

~

~

~

01

~~ MMM

1. , Production is dominant SUSY process at LHC ( )g~ q~ ggqqgqpp ~~ ,~~ ,~~02

02

021

02

01

~~ ,~~ ,~~

11102

~~ ~~

2. Interested in events with or pairs

3. & Branching Ratios are ~ 97%

Case 1: Signature at LHC

TEJets ' sExcess in 3 final states: , ,TEJets 2 2 TEJets 4 TEbJets 3


Case 1: Event Selection In order to target events with , we require ≥ 2 hadronic t’set = 50%, ffake = 1% for pT

vis > 20 GeV (CDF based)

Require large Missing Transverse Energy to target events

with

High PT jets are required to target events with squarks/gluinos

[1] References

• hep-ph/0608193, Phys. Lett. B649 (2007) 73. R. Arnowitt et al

02

~a.

b.

c.

d. GeVP

GeVEEEH

GeVEGeVE

GeVE

visT

jetT

jetTTT

jetT

jetT

T

20 ,40)(

600

100, 100

180

21

21

02

~

01

~


Case 1: Smoking Gun ObservablesSort τ’s by ET (ET1 > ET2 > …) & use

OS-LS method to extract t pairs from

the decays on a statistical basis

2~

2~

2~

2~

~

1

01

02

102

11

M

M

M

MMM end

02

~

Minpeakagives ~~ 01

02

MMm Smaller Smaller Smaller 0


Case 1: Smoking Gun Observables0

1~~

What is the dependence on the other SUSY masses?

Slope of the soft t PT distribution has a DM dependence

hep-ph/0603128


Slope of PT distribution contains ΔM Information.

01

~MX

02

~MX

MX

gMX ~

Case 1: More Observables

p p

g~

q~

01

~

02

~

~

1

~

q

q~q

q

~ 0

1~

We can combine the t’s to the jet from the squark decay to

provide another mass peak

endj

peakj MM

2~

2~

2~

2~

~

02

01

02 11

M

M

M

MMM

qq

endj

Mtt < Mttendpoint

Jets with ET > 100 GeV

Mjtt masses for each jet

Choose the 2nd largest value Peak value ~ “True” Value

Squark = 660 GeV

Squark = 840 GeV


ETj1 > 100 GeV, ET

j2,3,4 > 50 GeV [No e’s, m’s with pT > 20 GeV]

Meff > 400 GeV (Meff ETj1+ET

j2+ETj3+ET

j4+ ETmiss) [No b jets; eb ~ 50%]

ETmiss > max [100, 0.2 Meff]

Case 1: More Observables - Meff

m1/2 = 335 GeVMeff

peak = 1220 GeV

m1/2 = 351 GeVMeff

peak = 1274 GeV

m1/2 = 365 GeVMeff

peak = 1331 GeV

)~,~( LqgfAug. 19, 2009 Probing Supersymmetric Cosmology at the LHC 16

We have 6 observables defined as functions of 5 SUSY masses

Case 1: SUSY Mass Determination

)(

)(

) (

)(

)(

)(

6peakeff

01

025

(2)peak2

01

024

(2)peak1

01

023

(2)peak

012

01

021

peak

L

Lj

Lj

Lj

q~,g~fM

~,~,M,q~fM

~,~,M,q~fM

~,~,q~fM

~,MfSlope

~,~,MfM

)91.5( 8.09.5/

)19.3( 2.01.3/

0.26.10

;19141;15260

;21831 ;25748

01

02

01

02

~~

~~

~~

~~

theoryMM

theoryMM

M

MM

MM

g

g

gqL

Inverting Eqs. 10 fb-1

14119 GeV

(GeV) 01~

M

Testing gaugino universality at 15% level.


Case 1: mSUGRA ParametersEstablished the Co-Annihilation region

• detected low energy taus (pTvis > 20 GeV)

• observed the “smoking-gun” ditau mass

Determined SUSY Masses• e.g. LSP mass was measured to ~14%• tested gaugino universality to ~15% (10 fb-1)

Determining mSUGRA parameters• mSUGRA parameters cannot be determined

directly from the SUSY masses → we need an observable that can provide us with another independent function of A0 and tanb

• In general, it is NOT true that the determination of the SUSY masses from the mSUGRA parameters will give correct results (e.g. gaugino universality does not hold true)


),tan,,(?

),(

),tan,,(

),(

002/14

02/13peakeff

002/12peak

02/11peak

AmmX

mmXM

AmmXM

mmXM j

ETj1 > 100 GeV, ET

j2,3,4 > 50 GeV [No e’s, m’s with pT > 20 GeV]

Meff(b)

> 400 GeV (Meff(b)

ETj1=b+ET

j2+ETj3+ET

j4+ ETmiss) [j1 = b jet]

ETmiss > max [100, 0.2 Meff]

Case 1: More Observables - Meff (b)

Meff(b) can be used to probe A0 and tanb without measuring stop and

sbottom masses

tanb = 48Meff

(b)peak = 933 GeVtanb = 40Meff

(b)peak = 1026 GeVtanb = 32Meff

(b)peak = 1122 GeV

Meff(b)peak (GeV)

Arb

itra

ry S

cale

u

nit

s


Solved by inverting the following functions:

140tan

160

4350

5210

0

2/1

0

A

m

m

),tan,( 02/102

~01

AmmZh

1fb 10 L

1fb 50

)fb 70( %1.4

)fb 30( %2.6/1

12~

2~ 0

101

hh

),tan,,(

),(

),tan,,(

),(

002/14peak )(

eff

02/13peakeff

002/12peak

02/11peak

AmmXM

mmXM

AmmXM

mmXM

b

j

10 fb-1

Case 1: mSUGRA Parameters


Conclusion

Case No. 2

SuspectOver-dense DM

ReportPRD 79 (2009) 055002

Minimal SUGRA

)( 3 22 SnnvHndt

dneq

m1/2

m0

Lahanas, Mavromatos, Nanopoulos, PLB 649 (2007) 63

A0 = 0, tanb = 40

Smoking gun signals in the region?

Dilaton effect creates new parameter space.


m1/2= 440 GeV; m0 = 471 GeV

m1/2= 600 GeV; m0 = 440 GeV

86.8%

77.0%

2 Reference Points

Appendix

Appendix


Case 2(a) : Higgs

1~

Lu~

01χ~

02χ~

g~

h

1χ~

m1/2=440, m0=471, tanb=40, mtop=175

Re~

u

87%

10411044

500

393

181

341

114

46213%

Z91

N(b) > 2 with PT > 100 GeV; 0.4< DRbb < 1

ETmiss > 180 GeV;

N(jet) > 2 with ET > 200 GeV; ET

miss + ETj1 + ET

j2 > 600 GeV


w/ side-band BG subtraction

where:

Meff ETj1+ET

j2+ETj3+ET

j4+ ETmiss

[No b jets; eb ~ 50%]

Meff(b)

ETj1=b+ET

j2+ETj3+ET

j4+ ETmiss

Meff(bb)

ETj1=b+ET

j2=b+ETj3+ET

j4+ ETmiss

)tan(

)tan(

)(

)(

00214peak )(

eff

00213peak )(

eff

0212peakeff

0211point end

A,,m,mXM

A,,m,mXM

m,mXM

m,mXM

/bb

/b

/

/jbb

4 Kinematical VariablesSide-band BG subtraction

(GeV) (2)bbjM

(GeV) bbM

71)4(fb 500 01 m

4801/2 m

4001/2 m


Band = Uncertainties with 1000 fb-1

Kinematical Templates


Determining mSUGRA ParametersSolved by inverting the following functions:

)tan(

)tan(

)(

)(

00214peak )(

eff

00213peak )(

eff

0212peakeff

0211point end

A,,m,mXM

A,,m,mXM

m,mXM

m,mXM

/bb

/b

/

/jbb


Determining Wh2


1839tan

950

15440

50472

0

21

0

A

m

m

/

),tan,( 02/102

~01

AmmZh 1fb 1000 L

%~h/h ~~ 150ΩΩ 2201

01

)tan(

)tan(

)(

)(

00214peak )(

eff

00213peak )(

eff

0212peakeff

0211point end

A,,m,mXM

A,,m,mXM

m,mXM

m,mXM

/bb

/b

/

/jbb

1000 fb-1

Note: These regions have large Wh2 if one just calculate based on standard cosmology. We put a factor of 0.1 for this non-standard cosmology.


Case 2(b) : Stau and Higgs

1~

Lu~

01χ~

02χ~

g~

h

1χ~

m1/2=600, m0=440, tanb=40, mtop=175

Re~

u

20.5%

13661252

494

376

249

462

114

46277%

Follow Case 2(a) and Case 1

)tan(

)tan(

)(

)(

00214peak

00213peak )(

eff

0212peakeff

0211(2)peak

A,,m,mXM

A,,m,mXM

m,mXM

m,mXM

/

/b

/

/j

)tan(

)tan(

)(

)(

00214peak )(

eff

00213peak )(

eff

0212peakeff

0211point end

A,,m,mXM

A,,m,mXM

m,mXM

m,mXM

/bb

/b

/

/jbb


Determining Wh2


340tan

450

6600

23440

0

21

0

A

m

m

/

),tan,( 02/102

~01

AmmZh 1fb 500 L

%~h/h ~~ 19ΩΩ 2201

01

)tan(

)tan(

)(

)(

00214peak

00213peak )(

eff

0212peakeff

0211(2)peak

A,,m,mXM

A,,m,mXM

m,mXM

m,mXM

/

/b

/

/j

500 fb-1

b/c stau helps to determine tanb accurately.Aug. 19, 2009 Probing Supersymmetric Cosmology at the LHC 29

Case 2 SummaryOver-dense Dark Matter Region: sOD-CDM ~ sCDM /10

Implication at the LHC: Region where c2

0 decays to HiggsdWCDM /WCDM ~ 150% (1000 fb-1)

Region where c20 decays to stau and Higgs

dWCDM /WCDM ~ 20% (500 fb-1)

Future Work: o More over-dense and under-dense cases?


Case No. 3

Suspect HB/FP

Report In progress

Minimal SUGRA

3 22eqnnvHn

dt

dn

Prospects at the LHC A few mass measurements are available: 2nd and 3rd neutralinos, and gluino

QuestionCan we make a cosmological measurement?

g~

0i

~

q~ l~ Z

ZZ

Z

Abram Krislock’s image of HB/FP, October 18, 2008

m0, A0, m, tanb

m1/2, , m tanb


0

0

0

0

2

1

0

scMssM

ccMcsM

scMccMM

ssMcsMM

WZWZ

WZWZ

WZWZ

WZWZ

~Μ

0

0

0

0

2

1

0

scMssM

ccMcsM

scMccMM

ssMcsMM

WZWZ

WZWZ

WZWZ

WZWZ

~Μ

A4x4 (m1/2, m, tan b )

g~M 01

02

21 ~~ MMD 01

03

31 ~~ MMD

Part 1 : New to Probe Wh2

)tan( 212

01

,,mZh /~


dD21 and dD32 dm and d tanb

dD21/D21 dD31/D31

d

tan

b

/ tan

b

d

tan

b

/ tan

b

dm/m dm/m

0g~g~ M/MassumingExample (m = 195, tanb = 10):

%.D

D71

21

21

%.D

D11

31

31

%.M

M

g~

g~ 54

(1) D. Tovey, “Dark Matter Searches of ATLAS,” PPC 2007(2) H. Baer et al., “Precision Gluino Mass at the LHC in SUSY Models with Decoupled

Scalars,” Phys. Rev. D75, 095010 (2007), reporting 8% with 100 fb-1

(1) (1) (2)

300 fb-1

Let’s test this idea:

%M

M

h

h 1

arbitrary scale

arbitrary scale


Wh2 Determination

LHC Goal: D21 and D32 at 1-2% and gluino mass at 5%

%.70

%~ 31tan

tan

%~h

h282

2

%.m

m65

1/2

1/2


Reconstructing two top quarks!e.g., "Perspectives for the detection and measurement of Supersymmetry in the focus point region of mSUGRA models with the ATLAS detector at LHC,"U. De Sanctis, T. Lari, S. Montesano, C. Troncon, arXiv:0704.2515v1 [hep-ex] (Eur.Phys.J.C52:743-758,2007) No gluino mass measurement.

Question (& HW)Can we improve the gluino mass measurement by using a simultaneous detection of neutralinos and tops?

Part 2 : Mass Measurements


CSI Summary Reports: mSUGRA

tanb = 40

A0 = 0, m > 0

ab

c


a

bc

m0 (

GeV

)

m1/2 (GeV)

Over-dense DM Region

Coannihilation Region

HB/Focus Point Region

Note: g-2 data may still be controversial.

1

2

3


))()(())()((

01

01

02

~lljjbjjb

~llWbWb

~ttg~

“Smoking Gun Signal” Snapshots

tanb = 40

A0 = 0, m > 0

ab

c


a

bc

m0 (

GeV

)

m1/2 (GeV)

01

02

~~~

01

01

02

~bb

~h~

LS

OS

OS-LS

PRL100 (2008) 231802

PRD 79 (2009) 055002

T. Kamon, Talk at“The LHC and Dark Matter”Univ. of Michigan, Jan. 7, 2009

1

2

3


Goals


Our main goal is to develop techniques/methods to extract the relic density from measurements at the Large Hadron Collider.

Standard Cosmology vs. Non-Standard Cosmology

Standard:

mSUGRA Co-Annihilation Region mSUGRA Focus Point Region

Non-Standard:

Over-dense Dark Matter Region Minimal vs. Non-Minimal scenarios

Minimal: mSUGRA Non-Minimal: Work in Progress (see backup slides)

Goals

[Case 1] “Coannihilation (CA)” RegionArnowitt, Dutta, Gurrola,*) Kamon, Krislock,*) Toback, PRL100 (2008) 231802 For earlier studies, see Arnowitt et al., PLB 649

(2007) 73; Arnowitt et al., PLB 639 (2006) 46

[Case 2] “Over-dense Dark Matter” RegionDutta, Gurrola,*) Kamon, Krislock,*) Lahanas, Mavromatos, NanopoulosPRD 79 (2009) 055002

[Case 3] “HB/Focus Point” RegionArnowitt, Dutta, Flanagan,#) Gurrola,*) Kamon, Kolev, Krislock*)

[Case 4] “Non-universality” Arnowitt, Dutta, Kamon, Kolev, Krislock*)

[Case 5] New project 1Dutta, Kamon, Krislock,*) Gupta

*) Graduate student, #) REU student

3 22eqnnvHn

dt

dn )( 3 22 SnnvHn

dt

dneq

W - 1Constant in

time?e.g., Quintessence – Scalar field dark energy

[Case 6] New project 2 Allahverdi, Bornhauser, Dutta, Kamon, Richardson-McDaniel*)


SummaryGoal: Develop technique(s) to test minimal and non-minimal scenarios and extract Wh2 (standard and non-standard cosmology cases) at the LHC where a limited number of SUSY mass measurements are available.

So far 4 cases were studied or are being studied:Case 1: Coannihilation regionCase 2: Over-dense DM region (sOdCDM ~ sCDM /10)Case 3: HB/Focus Point regionCase 4: Non-universal HiggsFuture: Further improvements New cases … in progress

CSI: Cosmology at the LHC

Collider Scene Investigation


Backup Slides

Case No. 4

SuspectNon-universal Higgs

Report In progress

Non-minimal SUGRA

3 22eqnnvHn

dt

dn

[Non-universality Case] Is a cosmological measurement possible?

1) Start with over-abundance region in SSC-like mSUGRA (e.g., m1/2 = 500, m0 = 360, mHu = 360)

2) Reduce Higgs coupling parameter, m, by increasing mHu (m1/2 = 500, m0 = 360, mHu =732) Extra contributions to Wh2

More annihilation (less abundance) Normal values of Wh2

3) Find smoking gun signals

4) Technique to calculate Wh2

%%~~%%~%.%~W~

9992

9858

4242

SSCU-Non

102

1

011

W’s

Start with “JW”N(j) > 2 with pT > 30 GeVN(b) > 0 with pT > 30 GeVN(t) = 0 with pT > 20 GeV

ETmiss > 180 GeV;

N(J) > 2 with ET > 200 GeV; ET

miss + ETJ1 + ET

J2 > 600 GeV

Note there might be b-jets and/or t-jets in event, but not counted as “J” nor “j”.

500-360-732

Endpoint = 774 GeVTure = 739 GeV (c4

0)

MJW

Ture = 739 GeV (c40)

&Jet Mix to

extract W’s

&

Ture = 714 GeV (c1+/-)

Appendix

[Vetoing events with any t’ s with pT > 20 GeV]

m1/2-m0-mHu 500-360-732 500-360-694 500-360-582

Wh2 0.110 0.211 0.462

MJW(q~C1W+N1) 714 (0.20*0.42) 813 (0.31*0.48) 867 (0.57*0.31)

MJW(q~C2W+N2 /t h) 727 (0.46*0.92) 650 (0.35*0.54) 652 (0.087*0.30)

MJW(q~C2W+N3Z) 652 (0.46*0.18*0.46) NAN (0.35*0.00) NAN (0.087*0.00)

MJW(q~N4W+C1) 739 (0.24*0.74) 654 (0.19*0.85) 650 (0.053*0.56)

MbW(t1C1W+N1) 485 550 594

gluino 1161 1161 1161

uL, uR 1113, 1078 1111, 1077 1111, 1076

b1, b2 ; t1, t2 946, 989; 781, 992 948, 993; 787, 996 954, 1005; 787, 996

C1, C2 291, 427 329, 442 376, 511

N1~N4 199, 293, 316, 432 202, 328, 368, 445 205, 375, 482, 511

500-360-694

MJW, shifting with mHu500-360-582500-360-732

867813739

Endpoint = 774 GeVTure = 739 GeV (c4

0) Endpoint = 856 GeVTure = 813 GeV (c1

+/-)Endpoint = 900 GeVTure = 867 GeV (c1

+/-)

Extraction of Model Parameters

Work in Progress …

Observable Model ParametersMeff(m0, m1/2)

m0, m1/2MJtt(m0, m1/2)

MJW(m0, m1/2, m(mHu), tanb), m(mHu), tanb

MWtt(m1/2, m(mHu), tanb)

Meff(b)(m0, m1/2, m(mHu), tanb, A0) A0

Case No. 5

Suspect Hints from Tevatron

Report In progress

Minimal-type SO(10)

3 22eqnnvHn

dt

dn


Case No. 6

Suspect ?

Report In progress

Non-minimal SUGRA

3 22eqnnvHn

dt

dn

01

~01~

01~


Bsmm

From the Tevatron

B (Bs ) : “Prospect in 2002” and Now

CDF(3.7 fb-1)

CDF(1.9 fb-1)

51

Cases 1 & 2

OS-LS Slope (pTsoft )

Uncertainty Bands with 10 fb-1

(GeV) g~M

Independent of the gluino masses!

)( ),( 01

01

02

21peak

~~~ M,MfslopeM,M,MfM

Mjtt Distribution

endpeak jj MM 2~

2~

2~

2~

~

02

01

02 11

M

M

M

MMM

qq

endj

1) Mtt < Mttendpoint; Jets with ET > 100 GeV; Mjtt masses for each jet

2) Choose the 2nd large value Peak value ~ True Value

Mjtt(2) (GeV)

)( 01

02

3(2)peak

~~q~j M,M,MfML

)( ), ( 01

02

01

02

5(2)peak

24(2)peak

1 ~~q~j~~q~j M,M,M,MfMM,M,M,MfMLL

c20 Decay Branching Ratios

m1/2= 500 GeV, m0 = 470 GeV

m1/2= 600 GeV, m0 = 440 GeV

Case 3

56

Gluino Decays 12 ~Z~

ETmiss > 150 GeV

GeV) 50( )( TEjN

(GeV) )(M

2)( jN

stotal = 3.1 pb

OSDF

OSSF

GeV) 10( 2)( TpN

01

032 ~~

,

19%5.3%11% 10%


1fb 500

(GeV) )( jjbM

))()(( 01

02 ~bWbW~ttg~

Simultaneous Detection of Neutralinos and Top(s)

1fb 300

Working on the gluino mass estimate …

ETmiss + Dilepton + Jets

[1]

N(ℓ) > 2 pT > 10 GeV; |h| < 2.5

[2]

ETmiss > 150 GeV

[3]

Selection of W jj pT(j) > 30 GeV; 0.4 < DR(j,j) < 1.5M(jj) < 78 15 GeV

[4]

Selection of t Wb pT(b) > 30 GeV0.4 < DR(jj, b) < 2

(GeV) )(M

)OSDF(OSSF eee


Case 4

59

JetMix: Hunt for Wjj

N(ji) > 2 with pT > 30 GeV

ETmiss > 180 GeV;

N(J) > 2 with ET > 200 GeV; ET

miss + ETJ1 + ET

J2 > 600 GeV

For each ji in Event X, M(ji jk) is calculated with jk in Event X-1

M(ji jk)

M(ji jk)

M(ji jk) = M(ji jk) - M(ji jk)

M(ji jk)

g

e

e

01~

02~

[1] So far, the world of physics has been described by the Standard Model (SM). SM does NOT provide a solution to the Dark Matter problem.

[2] Supersymmetry

Every SM Fermion (Boson) has a Boson (Fermion) supersymmetry partner (example: )

[3] Supersymmetry (SUSY) extensions of the SM naturally provide a weakly interacting massive particle as a Cold Dark Matter candidate: Lightest SUSY Particle (LSP)

[4] We choose to work with a theoretically and experimentally well motivated model: Minimal Supergravity (mSUGRA): LSP =

[5] Within the mSUGRA framework,

is required to produce the correct DM abundance.

Dark Matter and Supersymmetry

Region)ation (CoAnnihil GeV 155~01

~~ MMM

01

~

XX~

03/22/08 Dark Matter at the LHC 5

Documents

Probing Supersymmetric Cosmology at the LHC Alfredo Gurrola On behalf of TAMU (full list of collaborators in the slides to follow) Karlsruhe, Germany -