June 8, 2007 LPC Early CMS Physics 1

Relic Density in MET+Jets+Taus Sample

at the LHC

Teruki KamonTexas A&M University

[1] Physics Case in MET+Jets+Taus Sample

[2] Specific Tasks on MET+Jets+Taus Events

June 8, 2007 LPC Early CMS Physics 2

[1] Physics Case in MET+Jets+Taus Sample

1) Phys. Lett. B 639 (2006) 46R. Arnowitt, D. Butta, T. Kamon, N. Kolev, D. Toback

2) Phys. Lett. B 649 (2007) 73R. Arnowitt, A. Aurisano, D. Butta, T. Kamon, N. Kolev,

P. Simeon, D. Toback, P. Wagner

3) To appearR. Arnowitt, D. Butta, A. Gurrola, T. Kamon, A.

Krislock, D. Toback[2] Specific Tasks on MET+Jets+Taus EventsJonathan Asaadi, Adam Aurisano, Alfredo Gurrola,

Teruki Kamon, Chi-Nhan Nguyen, Alexei Safonov, David Toback,

Michael Weinberger

June 8, 2007 LPC Early CMS Physics 3

4

3

2

1splitting normal matter and dark matter apart

– Another Clear Evidence of Dark Matter – (8/21/06)

Dark Matter(Gravitational Lensing)

Ordinary Matter(NASA’s Chandra XObservatory)

Cosmic Collision of 2 Galaxy Clusters

time

Approximately the same size asthe Milky Way

June 8, 2007 LPC Early CMS Physics 4

8

pb 0.9

1

230

2

2

ann

0 ann

201

mv

dxv

~h

.

fx

~

8

pb 0.9

1

230

2

2

ann

0 ann

201

mv

dxv

~h

.

fx

~

Particle Physics and CosmologyS

US

YS

US

Y

CDM = Neutralino ( )CDM = Neutralino ( )01~

Ast

rop

hys

ics

Ast

rop

hys

ics

SUSY is an interesting class of models to provide a massive neutral particle (m ~ 100 GeV) and weakly interacting (WIMP).

011

~~ MMM Δ Griest, Seckel ’91

June 8, 2007 LPC Early CMS Physics 5

Minimal Supergravity (mSUGRA)4 parameters + 1 sign

m1/2 Common gaugino mass at MG

m0 Common scalar mass at MG

A0 Trilinear couping at MG

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

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

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

m0 Common scalar mass at MG

A0 Trilinear couping at MG

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

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

Experimental Constraints

(WMAP) 0.1290.094

2)(g 1027 10

104.5 )(Br 102.2

GeV 104 &GeV 114

2

10

44

charginoHiggs

01

h

a

sb

MM

~

μ

June 8, 2007 LPC Early CMS Physics 6

Experimental Constraints

Where are WMAP Favored regions?

Magnetic Moment of Muon

Higgs Mass (Mh)

Branching Ratio b s

Mas

s o

f S

qu

arks

an

d S

lep

ton

s

Mass of Gauginos

No Neutralino LSP

Excluded

Exc

lud

ed

June 8, 2007 LPC Early CMS Physics 7

Dark Matter Allowed Region

Magnetic Moment of Muon

Higgs Mass (Mh)

Branching Ratio b s

Mas

s o

f S

qu

arks

an

d S

lep

ton

s

Mass of Gauginos

No Neutralino LSP

Excluded

Exc

lud

ed

WMAP Favored region

June 8, 2007 LPC Early CMS Physics 8

[Neutralino-stau coannihilation region]

[Focus point region]The lightest neutralino has a larger higgsino component

[A-annihilation funnel region]This appears for large values of m1/2

Note: this narrow band does not disappear even with accurate measurement of CDM.

Dark Matter Allowed Regions

tyuniversari gaugino with

0.4~ ,0.8~ ,2.8~ 1/21/21/2 01

02

mMmMmMχ~χ~g~

tyuniversari gaugino with

0.4~ ,0.8~ ,2.8~ 1/21/21/2 01

02

mMmMmMχ~χ~g~

mSUGRA

June 8, 2007 LPC Early CMS Physics 9

tan= 40, > 0, A0 = 0

Can we measure M at colliders?

Phys. Lett. B 649 (2007) 73

Coannihilation Region

GeV 155

011

~

MMM ~~

June 8, 2007 LPC Early CMS Physics 10

>4 jet + ETmiss

+ >2

SUSY in Early Stage at the LHCO

ne

of t

he

key

rea

ctio

ns

Uni

que

kine

mat

ics

GeV 155

011

~

MMM ~~

June 8, 2007 LPC Early CMS Physics 11

Kinematical Cuts and Event Selection ET

j1 > 100 GeV, ETj2,3,4 > 50 GeV

Meff > 400 GeV (Meff ETj1+ET

j2+ETj3+ET

j4+ ETmiss)

ETmiss > max [100, 0.2 Meff]

Phys. Rev. D 55 (1997) 5520

Example Analysis

June 8, 2007 LPC Early CMS Physics 12

SUSY mass scale could be measured with an accuracy of 10-20%

This measurement does not tell us whether the model can generate the right amount of dark matter

The dark matter content is measured to be 23% with an accuracy of around 5% at WMAPQuestion:To what accuracy can we calculate the relic density based on the measurements at the LHC?

Meff and Relic Density

June 8, 2007 LPC Early CMS Physics 13

>4 jet + ETmiss

+ >2

Anatomy: PTsoft

ET > 20 GeV is essential!

low energyhigh energy

Slope of PT distribution contains ΔM information

More events for larger MDetecting low energy ’s are an enormous challenge for the detectors.

June 8, 2007 LPC Early CMS Physics 14

OS

Low OS PT histogram with PT of softer ; High OS PT histogram with PT of harder

02

~EETTmissmiss + 2j + 2 + 2j + 2 Analysis Path Analysis Path

Cuts to reduce the SM backgrounds (W+jets, …)

ETmiss > 180 GeV, ET

j1 > 100 GeV, ETj2 > 100 GeV,

ETmiss + ET

j1 + ETj2 > 600 GeV

PT > 20 GeV, PT

> 40 GeV ( = 50% , fake rate 1%)

Low OS-LS

High OS-LS

Low LS

High LS

Low OS

High OS

LS

Low OS PT histogram with PT of softer ; High OS PT histogram with PT of harder

Look at pairs and CATEGORIZE them as opposite (OS) or like sign (LS)

June 8, 2007 LPC Early CMS Physics 15

OS

OS-LS

LS

[1] ETmiss , at least 2 jets, at least 2 ’s with PT

vis > 20, 40 GeV

[2] = 50% , fake rate 1%

[3] Cuts: ETjet1 > 100 GeV, ET

jet2 > 100 GeV, ETmiss > 180 GeV

ETjet1 + ET

jet2 + ETmiss > 600 GeV

PTsoft in OSLS

GeV 10.6

GeV 3260

GeV 831

02

M

.M

M

~

g~

GeV 10.6

GeV 3260

GeV 831

02

M

.M

M

~

g~

June 8, 2007 LPC Early CMS Physics 16

We still see the dependence of the PT slope on M using OSLS method,

GeV 3260

GeV 831

02

.M

M

~

g~

PTsoft(OSLS) : M Dependence

GeV 015.M

GeV 75.M

GeV 610.M

June 8, 2007 LPC Early CMS Physics 17

Anatomy: Di-tau Mass Distribution

10 fb1

LSOS

OSLS

Mpeak = 47.1 GeV

Mmax(true) = 78.7 GeV

)?( 02

peak

~M,MfM

OSLS counts with M< 100 GeV:Top : 6 countsW+jets : 1 countSUSY : 125 counts 11 2

2

2

2max

1

01

02

102

~

~

~

~

~M

M

M

MMM 11 2

2

2

2max

1

01

02

102

~

~

~

~

~M

M

M

MMM

Phys. Lett. B 639 (2006) 46

June 8, 2007 LPC Early CMS Physics 18

Anatomy: M(j,,)a) if ET

j1 ETj2 > 100 GeV

j = j2

b) if ETj1 ET

j2 < 100 GeVj = jn with smaller R(, jn)

OS

LS

OSLS

Probing MSquark – MLSP

June 8, 2007 LPC Early CMS Physics 19

How to Establish the DiscoveryPhys. Lett. B 639 (2006) 46Phys. Lett. B 649 (2007) 73

Work in progress

[1] NOSLS (Number of OSLS counts) 5 significance where Significance = NOSLS / NOS+LS

[2] Clear peak (Mpeak) and end-point (Mmax) in di-tau mass distribution for OSLS pairsAre they consistent with the decay kinematics?

[3] Mpeak (and Mmax) on M and M2

0.

[4] PT slope is used to determine M.

[5] M(j,,)

ObservablesObservables

June 8, 2007 LPC Early CMS Physics 20

Example Translation

1/21/21/2 0.4~ ,0.8~ ,2.8~

tyuniversari gaugino with

models mSUGRAfor general In

01

02

mMmMmMχ~χ~g~

0.1 201

h~

0)(

0

40tan

GeV 350

GeV 210

0

1/2

0

sgn

A

m

m

GeV .6140

GeV 2151

GeV 260

GeV 830

01

02

χ~

τ~

χ~

g~

M

.M

M

MWe establish the dark allowed regions from the detailed features of the signals, and accurately measure the masses.

We calculate the relic density and compare with WMAP.

Work in progress

June 8, 2007 LPC Early CMS Physics 21

[1] Physics Case in MET+Jets+Taus Sample

1) Phys. Lett. B 639 (2006) 46R. Arnowitt, D. Butta, T. Kamon, N. Kolev, D. Toback

2) Phys. Lett. B 649 (2007) 73R. Arnowitt, A. Aurisano, D. Butta, T. Kamon, N. Kolev,

P. Simeon, D. Toback, P. Wagner

3) To appearR. Arnowitt, D. Butta, A. Gurrola, T. Kamon, A.

Krislock, D. Toback[2] Specific Tasks on MET+Jets+Taus EventsJonathan Asaadi, Adam Aurisano, Alfredo Gurrola,

Teruki Kamon, Chi-Nhan Nguyen, Alexei Safonov, David Toback,

Michael Weinberger

June 8, 2007 LPC Early CMS Physics 22

TAMU Activities Lepton+Tau Trigger for Z(for Calibration) :

Chi-Nhan Nguyen

Tau Energy - Expanding the CDF experience : Andrey Elagin

MET+Jet Trigger & Sample :Adam Aurisano, Michael Weinberger

MET correction with tau : Alfredo Gurrola, Chi-Nhan Nguyen

Meff Study with tau : Jonathan Asaadi, Alfredo Gurrola

June 8, 2007 LPC Early CMS Physics 23

Backups

June 8, 2007 LPC Early CMS Physics 24

Appendix 1: Reference Pointsm1/2 = 360 GeVm1/2 = 360 GeV

Mgluino = 830 GeV

June 8, 2007 LPC Early CMS Physics 25

Backups

June 8, 2007 LPC Early CMS Physics 26

Tau 101 – How to Find TauTau 101 – How to Find Tau

jet

jet

jet

June 8, 2007 LPC Early CMS Physics 27

TO FIND THE TAU’S

Particle Physics and Cosmology

Tau 101 QuizTau 101 Quiz

June 8, 2007 LPC Early CMS Physics 28

jetjet

jet

jet

jetjet

jet

jet

jet

jetjet

jet

Particle Physics and Cosmology

Tau 101 Quiz - AnswerTau 101 Quiz - Answer

June 8, 2007 LPC Early CMS Physics 29

So far in the laboratories we have seen the particles responsible for 4% of the universe.

The upcoming experiments will try to probe the nature of 23 % of the universe: dark matter.

Challenge:73% of the universe is still a major

puzzle.Not yet understood theoretically!

Conclusion

June 8, 2007 29June 8, 2007 Particle Physics and Cosmology

TO HELP SOLVE THE PUZZLE OF THE UNIVERSE.