Claudia Frugiuele Mixing stops at the LHC in collaboration with P - - PowerPoint PPT Presentation

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Claudia Frugiuele Mixing stops at the LHC in collaboration with P - - PowerPoint PPT Presentation

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Claudia Frugiuele Mixing stops at the LHC in collaboration with P . Agrawal hep ph 1304.3068 GGI 07/06/2013 Monday, 10 June 13 SUSY after the LHC first run Summary of CMS SUSY Results* in SMS framework LHCP 2013 m(mother)-m(LSP)=200 GeV

slide-1
SLIDE 1

Mixing stops at the LHC

Claudia Frugiuele

GGI 07/06/2013 in collaboration with P . Agrawal

hep ph 1304.3068

Monday, 10 June 13

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SLIDE 2

SUSY after the LHC first run

Mass scales [GeV] 200 400 600 800 1000 1200

χ ∼ l → l ~ χ ∼ χ ∼ ν τ ll → ± χ ∼ 2 χ ∼ χ ∼ χ ∼ W Z → 2 χ ∼ ± χ ∼ χ ∼ χ ∼ ν ν
  • l
+ l →
  • χ
∼ + χ ∼ χ ∼ χ ∼ ν τ τ τ → ± χ ∼ 2 χ ∼ χ ∼ χ ∼ ν lll → ± χ ∼ 2 χ ∼ χ ∼ bZ → b ~ χ ∼ tW → b ~ χ ∼ b → b ~ ) χ ∼ W → + χ ∼ b( → t ~ ) χ ∼ W → + χ ∼ b( → t ~ χ ∼ t → t ~ χ ∼ t → t ~ χ ∼ q → q ~ χ ∼ q → q ~ χ ∼ btW → g ~ ) χ ∼ γ → 2 χ ∼ qq( → g ~ ) χ ∼ W → ± χ ∼ | χ ∼ γ → 2 χ ∼ qq( → g ~ ) χ ∼ Z → 2 χ ∼ qq ( → g ~ ) χ ∼ ν ± l → ± χ ∼ qq( → g ~ ) χ ∼ t → t ~ t( → g ~ ) χ ∼ | χ ∼ W → ± χ ∼ qq( → g ~ ) χ ∼ | χ ∼ τ τ → 2 χ ∼ qq( → g ~ ) χ ∼
  • l
+ l → 2 χ ∼ qq ( → g ~ χ ∼ tt → g ~ χ ∼ bb → g ~ χ ∼ qq → g ~ χ ∼ qq → g ~ SUS-12-022 L=9.20 /fb SUS-13-008 L=19.50 /fb SUS-13-011 L=19.50 /fb x = 0.25 x = 0.50 x = 0.75 SUS-13-008 L=19.50 /fb SUS-12-001 L=4.93 /fb SUS-11-010 L=4.98 /fb SUS-12-022 L=9.20 /fb x = 0.05 x = 0.50 x = 0.95 SUS-12-022 L=9.20 /fb SUS-12-028 L=11.70 /fb SUS-12-028 L=11.70 /fb SUS-13-007 SUS-13-008 L=19.40 19.50 /fb SUS-12-024 SUS-12-028 L=19.40 11.70 /fb SUS-12-001 L=4.93 /fb SUS-12-028 L=11.70 /fb SUS-12-005 SUS-11-024 L=4.70 /fb SUS-13-008 SUS-12-017 L=19.50 10.50 /fb SUS-12-005 SUS-11-024 L=4.70 /fb SUS-12-004 L=4.98 /fb SUS-12-022 L=9.20 /fb SUS-11-011 L=4.98 /fb SUS-13-008 L=19.50 /fb SUS-13-011 L=19.50 /fb left-handed top unpolarized top right-handed top SUS-11-024 SUS-12-005 L=4.70 /fb SUS-11-021 SUS-12-002 L=4.98 4.73 /fb x = 0.25 x = 0.50 x = 0.75 SUS-12-022 L=9.20 /fb x = 0.05 x = 0.50 x = 0.95 SUS-12-010 L=4.98 /fb x = 0.25 x = 0.50 x = 0.75 SUS-12-022 L=9.20 /fb SUS-11-030 L=4.98 /fb gluino production squark stop sbottom EWK gauginos slepton

Summary of CMS SUSY Results* in SMS framework CMS Preliminary

m(mother)-m(LSP)=200 GeV m(LSP)=0 GeV

LHCP 2013

= 7 TeV s = 8 TeV s

lsp

m ⋅

  • (1-x)
mother

m ⋅ = x

intermediate

m For decays with intermediate mass, Only a selection of available mass limits *Observed limits, theory uncertainties not included Probe *up to* the quoted mass limit Monday, 10 June 13

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SLIDE 3

Natural SUSY after the first run

Plot from Weiler talk on natural susy

Bounds on gluinos and degenerate1&2 generation squarks reached the TeV threshold... limits on gluino are already in tension with naturalness Dirac gluinos?

Monday, 10 June 13

slide-4
SLIDE 4

Natural SUSY after the first run

Plot from Weiler talk on natural susy

Bounds on Gluinos and degenerate1&2 generation squarks reached the TeV threshold... limits on gluino are already in tension with naturalness Dirac gluinos?

agnostic about the mechanism to raise the Higgs mass

Monday, 10 June 13

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SLIDE 5

Naturalness+LHC bounds on squarks

suggest SUSY breaking mediation knows about flavor exploring other structure beyond MFV what does this imply for the LHC pheno?

No much freedom in the MSSM due to the severe flavor problem somewhat large mixing allowed between right handed stop and charm ( Blanke,Giudice,Paradisi,Perez,Zupan,’13)

Monday, 10 June 13

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SLIDE 6

Having R symmetry ameliorates the flavor problem

  • Majorana masses for the gauginos
  • A term
  • Mu term

most of the dangerous contributions to flavor observable arise from R violating terms:

kribs,weiner,poppitz ’07

Beyond the MSSM?

Monday, 10 June 13

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SLIDE 7

∆F = 2

gluino Majorana mass insertion

∆F = 1

mu term

Monday, 10 June 13

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SLIDE 8

EDM bounds

no chirality flip from Majorana mass insertion or mu term suppressed by the Yukawa coupling

µ → eγ

Monday, 10 June 13

slide-9
SLIDE 9

c li s d d f

Flavor problem relaxed but not solved Mixing between first&second generation still suppressed by K0K0 mixing some flavor structure still required

even stronger bounds considering ✏K δ =

M 2

12

√

M 2

11M 2 22

Monday, 10 June 13

slide-10
SLIDE 10

R symmetry relax several of the flavor bounds interesting ingredient to build a flavorful SUSY breaking mediation mechanism allows larger flavor violation in the squark sector

what is the impact of this on the LHC phenomenology?

Monday, 10 June 13

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SLIDE 11

Flavor violating (FV) decay mode of the stop is dominant in a large region

  • f the parameter space

single top production

δLL/RR

23

=

M 2

23

√

M 2

22M 2 33 ∼ 1

δLL/RR

13

=

M 2

13

√

M 2

11M 2 33 ∼ 1

  • r

Mixed third generation at the LHC

kribs,martin,roy’09

Monday, 10 June 13

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SLIDE 12

(Light) stop NLSP

kinematically forbidden

m˜

t < mt + mLSP

m˜

t < µ < 300GeV

˜ t → t LSP

˜ t → bχ±

LSP gravitino, singlino or bino natural region if the stop is light also kinematically forbidden

better if it is pseudo-dirac

Monday, 10 June 13

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SLIDE 13

FV decay mode dominates over the 3 body decay

150 200 250 300 350 400 0.00 0.02 0.04 0.06 0.08 0.10

mt

~ @GeVD

sin2q

m˜

t − mLSP = 150 GeV

more compressed spectrum FV dominates for even smaller mixing angle contour plot

BR(˜ t → χ0j) = 90% BR(˜ t → Gj) = 90%

Monday, 10 June 13

slide-14
SLIDE 14

180 200 220 240 260 280 300 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35

mt

~ @GeVD

sin2q

Significant BR also when the decay into top+LSP is open!

BR(˜ t → jχ0) = 50%

BR(˜ t → jχ0) = 75%

BR(˜ t → jG) = 75%

BR(˜ t → jG) = 50%

massless LSP light stop FV is still the dominant decay mode

Monday, 10 June 13

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SLIDE 15

180 200 220 240 260 280 300 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35

mt

~ @GeVD

sin2q

Significant BR also when the decay into top+LSP is open!

BR(˜ t → jχ0) = 50%

BR(˜ t → jχ0) = 75%

BR(˜ t → jG) = 75%

BR(˜ t → jG) = 50%

massless LSP light stop FV is still the dominant decay mode heavier stops FV BR(˜ t → jLSP) ∼ sin2 θ

Monday, 10 June 13

slide-16
SLIDE 16

180 200 220 240 260 280 300 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35

mt

~ @GeVD

sin2q

Significant BR also when the decay into top+LSP is open!

BR(˜ t → jχ0) = 50%

BR(˜ t → jχ0) = 75%

BR(˜ t → jG) = 75%

BR(˜ t → jG) = 50%

massless LSP light stop FV is still the dominant decay mode heavier stops FV BR(˜ t → jLSP) ∼ sin2 θ

relax the bounds on the stop mass

(blanke et al)

Monday, 10 June 13

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SLIDE 17

MSSM with MFV

m˜

t < mb + mW + mLSP FV significant only for CKM suppressed

θtc ∼ vAytybVcbV ∗

tb

16π2 ˜ m2

log ΛUV

˜ m

∼ 10−5

compete with the 4 body decay

Monday, 10 June 13

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SLIDE 18

CDF Tevatron dedicated searches covered just the parameter space relevant for the MSSM

˜ t → c LSP

what about this region?

Monday, 10 June 13

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SLIDE 19

Stops searches at the LHC

both ATLAS and CMS are looking for stops in

˜ t → tχ0

˜ t → bχ+

[GeV]

1

t ~

m

100 200 300 400 500 600 700

1
  • +
m t < m 1 t ~ m 1
  • + m
W + m b < m 1 t ~ m

200 300 400 500 600

) 1
  • m
× = 2 1 ±
  • (
m 1 ±
  • +
m b < m 1 t ~ m < 106 GeV 1 ±
  • m
+5 GeV) 1
  • = m
1 ±
  • ( m
1 ±
  • +m
b < m 1 t ~ m < 103.5 GeV 1 ±
  • m

[GeV]

1
  • m

100 200 300 400 500 600

Observed limits )

theo
  • Observed limits (-1

Expected limits

1
  • m
× = 2 ± 1
  • m
  • 1
= 20-21 fb int L
  • 10 GeV
1 t ~ = m ± 1
  • m
  • 1
= 20.3 fb int L = 150 GeV ± 1
  • m
  • 1
= 20.7 fb int L = 106 GeV ± 1
  • m
  • 1
= 4.7 fb int L + 5 GeV 1
  • = m
± 1
  • m
  • 1
= 20.1 fb int L
  • 1
= 4.7 fb int L
  • 1
21 fb
  • int
L 1
  • W b
  • 1
= 20 fb int L

ATLAS Preliminary

production

1

t ~

1

t ~

Status: LHCP 2013 =8 TeV s

  • 1

= 20 - 21 fb

int

L =7 TeV s

  • 1

= 4.7 fb

int

L

0L ATLAS-CONF-2013-024 1L ATLAS-CONF-2013-037
  • 2L ATLAS-CONF-2013-048
0L ATLAS-CONF-2013-053
  • 1L ATLAS-CONF-2013-037
2L ATLAS-CONF-2013-048 1L CONF-2013-037, 2L CONF-2013-048 0L [1208.1447] 1L [1208.2590] 2L [1209.4186]
  • 2L [1208.4305], 1-2L [1209.2102]
  • 1-2L [1209.2102]
1
  • (*)

W

  • 1
±
  • ,
1 ±
  • b
  • 1

t ~

1
  • W b
  • 1

t ~ /

1
  • t
  • 1

t ~

1
  • t
  • 1

t ~ 0L,

1
  • t
  • 1

t ~ 1L,

1
  • t
  • 1

t ~ 2L,

1
  • W b
  • 1

t ~ 2L, + 5 GeV

1
  • = m
± 1
  • 0L, m

= 106 GeV

± 1
  • , m
1 ±
  • b
  • 1

t ~ 1-2L, = 150 GeV

± 1
  • , m
1 ±
  • b
  • 1

t ~ 1L,

  • 10 GeV
1 t ~

= m

± 1
  • , m
1 ±
  • b
  • 1

t ~ 2L,

1
  • m

× = 2

± 1
  • , m
1 ±
  • b
  • 1

t ~ 1-2L,

Monday, 10 June 13

slide-20
SLIDE 20

what about our topology?

no dedicated searches

Stop NLSP

[GeV]

1

t ~

m

200 300 400 500 600 700

[GeV]

1
  • m

50 100 150 200 250 300 350

1
  • t
  • 1

t ~ 0L,

1
  • t
  • 1

t ~ 1L,

1
  • t
  • 1

t ~ 2L,

1
  • W b
  • 1

t ~ 2L,

1
  • +m
t

< m

1 t ~

m

1
  • +

m

W

+ m

b

< m

1 t ~

m

1

  • W b
  • 1

t ~ /

1

  • t
  • 1

t ~ production,

1

t ~

1

t ~ Status: LHCP 2013

ATLAS Preliminary

  • 1

= 4.7 fb

int

L

  • 1

21 fb

  • int

L

1
  • W b
  • 1

= 20 fb

int

L

Observed limits )

theo
  • Observed limits (-1

Expected limits

0L CONF-2013-024 =8 TeV s

  • 1

= 20 - 21 fb

int

L =7 TeV s

  • 1

= 4.7 fb

int

L 1L CONF-2013-037

  • 2L CONF-2013-048

0L [1208.1447] 1L [1208.2590] 2L [1209.4186]

  • 3 body decay

Monday, 10 June 13

slide-21
SLIDE 21

Standard jets+MET searches ?

region interesting for us left uncostrained

m˜

t < 300 GeV

m˜

t − mLSP < 150 GeV

no limits

Monday, 10 June 13

slide-22
SLIDE 22

ISR dependence of the efficiency

important to include initial state radiation large MET from ISR recoil

in compressed spectrum the two LSPs are produced back to back as the mother particles

Monday, 10 June 13

slide-23
SLIDE 23

Our study

decay, parton shower and hadronization with Phytia We generated with MadGraph5

˜ t˜ t∗ ˜ t˜ t∗ + j ˜ t˜ t∗ + 2j

Matched sample

BR(˜ t → jLSP)=100%

Detector simulation with PGS Limits from CMS razor and alphaT analysis

Monday, 10 June 13

slide-24
SLIDE 24

CMS razor analysis

  • data driven background ( no heavy use
  • f MC simulations). Background has an

exponential shape in the razor variables.

R2

relate of the missing energy in the event and to the angle between the megajets

estimate of the energy scale of event

MR

Razor variables

At least two jets required- all the hard jets combined into megajets

  • inclusive search (jets+MET+(0,1,2)leptons)

Monday, 10 June 13

slide-25
SLIDE 25

wh dep yo

Cuts on razor variables

2D cuts more efficient to reduce the backgrounds without killing also signals

QCD multijet background killed by a cut on

R2

Monday, 10 June 13

slide-26
SLIDE 26

200 400 600 800 100 200 300 400 500

m˜

t [GeV]

mLSP [GeV]

m˜

t = mLSP

m˜

t = mW + mb + mLSP

m˜

t = mt + mLSP

Our limits

natural region m˜

t < µ < 300 GeV almost excluded

Monday, 10 June 13

slide-27
SLIDE 27

Razor almost close the light stop window?

delgado,giudice,isidori,pierini,strumia ’12

Monday, 10 June 13

slide-28
SLIDE 28

[GeV]

1

t ~

m

200 300 400 500 600 700

[GeV]

1

  • m

50 100 150 200 250 300 350

1
  • t
  • 1

t ~ 0L,

1
  • t
  • 1

t ~ 1L,

1
  • t
  • 1

t ~ 2L,

1
  • W b
  • 1

t ~ 2L,

1
  • +

m

t

< m

1 t ~

m

1
  • +

m

W

+ m

b

< m

1 t ~

m

1

  • W b
  • 1

t ~ /

1

  • t
  • 1

t ~ production,

1

t ~

1

t ~ Status: LHCP 2013

ATLAS Preliminary

  • 1

= 4.7 fb

int

L

  • 1

21 fb

  • int

L

1
  • W b
  • 1

= 20 fb

int

L

Observed limits )

theo

  • Observed limits (-1

Expected limits

0L CONF-2013-024 =8 TeV s

  • 1

= 20 - 21 fb

int

L =7 TeV s

  • 1

= 4.7 fb

int

L 1L CONF-2013-037

  • 2L CONF-2013-048

0L [1208.1447] 1L [1208.2590] 2L [1209.4186]

  • 175 GeV < m˜

t < 200 GeV

Left unconstrained by the dedicated searches

Monday, 10 June 13

slide-29
SLIDE 29

Razor almost close the light stop window?

stealth stop ruled

  • ut?

work in progress with P .Agrawal and J.Lykken

Monday, 10 June 13

slide-30
SLIDE 30

Summarizing..

  • Exploring scenarios beyond the MSSM can

improve existing searches and eventually suggest new ones, but LHC is already doing a pretty good job already.

  • CMS is updating its analysis to the compressed

region having also our scenario in mind.

  • it seems we really need to kill the missing energy
  • f the event to escape LHC searches and hide

SUSY

Monday, 10 June 13

slide-31
SLIDE 31

backup

Monday, 10 June 13

slide-32
SLIDE 32

New Adjoints superfields for each SM gauge group

Supersoft SUSY Breaking

R d2θ

M W 0 αW α i ψi

W 0

α ∼ Dθα

Dirac gauginos

ψ ˜

B ψ ˜

W ψ˜

g

D term spurion

Fox,Nelson,Weiner, 2002

N=2 SUSY gauge sector

Monday, 10 June 13