Progress report on sbottom and gluino reconstruction Massimiliano Chiorboli Universita and INFN...

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Progress report on sbottom and Progress report on sbottom and gluino reconstructiongluino reconstruction

Progress report on sbottom and Progress report on sbottom and gluino reconstructiongluino reconstruction

Massimiliano Chiorboli

Universita’ and INFN Catania

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

99.610 = LSP

186.01±145.8lR

379.72±211.4lL

186.820549qR

358.830570qL

379.140549.7bR

600.5tR522.5bL

412.5tL643.3g

Proposed Post-LEP Benchmarks for Supersymmetry Proposed Post-LEP Benchmarks for Supersymmetry (hep-ph/0106204)(hep-ph/0106204)Proposed Post-LEP Benchmarks for Supersymmetry Proposed Post-LEP Benchmarks for Supersymmetry (hep-ph/0106204)(hep-ph/0106204)

pb 41.41TOTSUSY

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Decay chainDecay chainDecay chainDecay chain

p

p

g~

b~

b

b

01

~

02

~ ~

0A

)( sign

10β tan

100m

250m

0

0

21

bb~

g~ pp

b~02

01

~

(15% bL, 10% bR)

(35 % bL, 22% bR)

(0.2 %)

01

~ ~

(60 %)

Event final state:

• 2 high pt isolated leptons OS

• 2 high pt b jets

• missing Et

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Event productionEvent productionEvent productionEvent production

2 isolated leptons, pT>15 GeV, ||<2.4

2 b-jets, pT>20 GeV, ||<2

• PYTHIA 6.152• CMSJET 4.801

SM bkg: tt, Z+jet, W+jet, ZZ, WW, ZW

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

First step: First step: 2200 l l++ll- - 11

00First step: First step: 2200 l l++ll- - 11

00

02

~ 01

~

~p

p

g~

b~

b

b

01

~

02

~ ~

GeV 85.32 M

)M)(MM(MM

2

χ

222

χmax01

02

~

~~~~

GeV 1.64 86.00 Mmax

Fit result:

)μM(μ )eM(e -

)μM(e -)μM(e - )μM(μ )eM(e -- Etmiss > 50 GeV

10 fb-1

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom reconstructionSbottom reconstructionSbottom reconstructionSbottom reconstruction

p

p

g~

b~

b

b

01

~

02

~ ~

Assuming M(10)

known!

p

M

M1p

01

02

~

~

GeV 92 M GeV 75

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom reconstructionSbottom reconstructionSbottom reconstructionSbottom reconstruction

Etmiss > 50 GeV Et

miss > 100 GeV Etmiss > 150 GeV

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom massSbottom massSbottom massSbottom mass

55.8

GeV 8.1516.4b)~M( 02

Result of fit:

GeV 7.549)b~

M(

GeV 5.522)b~

M(

R

L

Generated masses:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Gluino reconstructionGluino reconstructionGluino reconstructionGluino reconstruction

p

p

g~

b~

b

b

01

~

02

~ ~

b)b~

( angle

Etmiss > 150 GeV

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Gluino massGluino massGluino massGluino mass

9.54σ

GeV 7.2631.8bb)χ~M( 02

Result of fit:

GeV 643.3)gM( ~Generated mass:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Combinatorial suppressionCombinatorial suppressionCombinatorial suppressionCombinatorial suppression

tt~ g~ 1

t~ b,~ (2.7%), b~ 0221

(8%)

%) (3.5t ~ b~ 11

%) (1W t~ b~ 11

t~ b,~ (2.7%), b~ 0221

%) (1.6t ~ b~ 12

%) (1.2W t~ b~ 12

t~ b,~ (2.7%), b~ 0221

GeV 60 t)t~M(-)g~M(

GeV 200 b)~M(-)t~M(

GeV 170 t)~M(-)b~

M(

GeV 20 W)t~M(-)b~

M( GeV 330 b)~M(-)b

~M( 0

2

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Combinatorial suppressionCombinatorial suppressionCombinatorial suppressionCombinatorial suppression

Eb-jet 1 > 250 GeV

Sbottom Gluino

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Combinatorial suppressionCombinatorial suppressionCombinatorial suppressionCombinatorial suppression

Sbottom Gluino

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom massSbottom massSbottom massSbottom mass

68.8

GeV 7.7515.9b)~M( 02

Result of fit:

GeV 7.549)b~

M(

GeV 5.522)b~

M(

R

L

Generated masses:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Gluino massGluino massGluino massGluino mass

GeV 643.3)gM( ~Generated mass:

9.04σ

GeV 8.3639.3bb)χ~M( 02

Result of fit:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Dependence on M(ll)Dependence on M(ll)Dependence on M(ll)Dependence on M(ll)

GeV 92 M GeV 75 GeV 92 M GeV 60

GeV 92 M GeV 80

Sbottom

Gluino

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Dependence on M(Dependence on M())Dependence on M(Dependence on M())

M(10) true

M(10) = M(ll)

M(10) = M edge

p2p

M

M1p

01

02

~

~

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

estimationestimation estimationestimation

doesn’t depend on M(10) !

)b~

M(-)g~M(

GeV 30)~M( 01

)bM(-)gM(~~ )bM(-)gM(~~

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

estimationestimation estimationestimation

6.32σ

GeV 6.387.5b)χ~M(bb)χ~M( 02

02

Result of fit:

)bM(-)gM(~~ )bM(-)gM(~~

GeV 6.93)b~

M(-)g~M(

GeV 8.120)b~

M(-)g~M(

R

L

Generated values:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

With 60 fbWith 60 fb-1-1With 60 fbWith 60 fb-1-1

60 fb-1

Sbottom

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

cos (b2-sb) cos(b1-ll)

cos(b2-ll) cos(b1-b2)

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom(s) with 60 fbSbottom(s) with 60 fb-1-1Sbottom(s) with 60 fbSbottom(s) with 60 fb-1-1

2.25

GeV 5.45.824b)~M( 02

Result of fit:

2.31

GeV 10.04.555b)~M( 02

Etmiss > 150 GeV

Eb-jet 1 > 250 GeV

cos (b2-sb)>0.

cos(b1-ll)>0.

cos(b2-ll)>0.

cos(b1-b2)>0.

GeV 7.549)b~

M(

GeV 5.522)b~

M(

R

L

Generated masses:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Gluino with 60 fbGluino with 60 fb-1-1Gluino with 60 fbGluino with 60 fb-1-1

2.84σ

GeV 4.2633.5bb)χ~M( 02

Result of fit:60 fb-1

GeV 643.3)gM( ~Generated mass:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

with 60 fbwith 60 fb-1-1 with 60 fbwith 60 fb-1-1

60 fb-1

0.37σ

GeV 3.50.99b)χ~M(bb)χ~M( 02

02

Result of fit:

)bM(-)gM(~~ )bM(-)gM(~~

GeV 6.93)b~

M(-)g~M(

GeV 8.120)b~

M(-)g~M(

R

L

Generated values:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

152.510 = LSP

294.51±193.4lR

546.12±299.6lL

294.820780qR

532.430814qL

545.340771.3bR

800.8tR723.0bL

589.4tL919.8g

Point GPoint GPoint GPoint G

pb 6.00TOTSUSY

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

tt~ g~ 1

t~ b,~ %), (2.7 %) (8.5 b~ 0221

(16%) (8 %)

Decay chainDecay chainDecay chainDecay chain

bb~

g~ pp

b~02

(16% bL, 10% bR)

(15 % bL, 28% bR)

01

~ ~

(8 %) (60 %)

%) (3.5 %) (7t ~ b~ 11

(1%) %) (3W t~ b~ 11

%) (1.6 %) (2.6t ~ b~ 12

%) (1.2 %) (3.2W t~ b~ 12

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Dilepton EdgeDilepton EdgeDilepton EdgeDilepton Edge

60 fb-1

)μM(μ )eM(e -

E(ll) > 160 GeV

SUSY only l

slepton l

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Dilepton EdgeDilepton EdgeDilepton EdgeDilepton Edge

Etmiss > 100 GeVEt

miss > 50 GeV Etmiss > 150 GeV

E(ll) > 160 GeV

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Dilepton EdgeDilepton EdgeDilepton EdgeDilepton Edge

)μM(μ )eM(e - )μM(e -)μM(e - )μM(μ )eM(e --

E(ll) > 160 GeV Etmiss > 200 GeV

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom and gluinoSbottom and gluinoSbottom and gluinoSbottom and gluino

Etmiss > 200 GeV

Sbottom Gluino

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Combinatorial suppressionCombinatorial suppressionCombinatorial suppressionCombinatorial suppression

Eb-jet 1 > 300 GeV

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

SM suppressionSM suppressionSM suppressionSM suppression

(ll-Etmiss)

(ll) (bb)

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom and gluinoSbottom and gluinoSbottom and gluinoSbottom and gluino

Etmiss > 200 GeV

Eb-jet 1 > 300 GeV

(ll-Etmiss) > -0.8

(ll) > -0.6

(bb) > -0.7

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom peakSbottom peakSbottom peakSbottom peak

6.82

GeV 8.743b)~M( 02

Result of fit:

GeV 3.771)b~

M(

GeV 0.723)b~

M(

R

L

Generated masses:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Guino peakGuino peakGuino peakGuino peak

7.31σ

GeV 1.909bb)χ~M( 02

Result of fit:

GeV 8.199)g~M(

Generated mass:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

estimationestimation estimationestimation

This needs better understanding of the SM bkg behaviour!

27.9σ

GeV 5.7168.1b)χ~M(bb)χ~M( 02

02

Result of fit:

)bM(-)gM(~~ )bM(-)gM(~~

GeV 5.148)b~

M(-)g~M(

GeV 8.196)b~

M(-)g~M(

R

L

Generated values:

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Point G with 150 fbPoint G with 150 fb-1-1Point G with 150 fbPoint G with 150 fb-1-1

No Pile Up!

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Sbottom and gluino with 150 fbSbottom and gluino with 150 fb-1-1Sbottom and gluino with 150 fbSbottom and gluino with 150 fb-1-1

Sbottom Gluino

M(g)-M(b)

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

ConclusionsConclusionsConclusionsConclusions

Point G, with 60 fb-1

• Sbottom and gluino seem to be visible

• estimation of M(l+l-)max

• sbottom reconstruction with Resol. ~ 10 %, but 2 sbottoms not resolved

• gluino reconstruction with Resol. < 10 %

• M(g) - M(b) estimation, independent of M(10), with Err ~ 4 %

Point B, with 10 fb-1

~2~

2~

2~

2~ M)MM)(MM( 0

102

• Maybe we can separate the 2 sbottoms

Point B, with 60 fb-1

8 Mar 2002CMS Week - Physics Meeting Massimiliano Chiorboli

Eb-jet 1

PTb-jet 1

b-jet 1

Eb-jet 2

PTb-jet 2

b-jet 2

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