Displaced RPV SUSY & Baryogenesis Yanou Cui Perimeter - - PowerPoint PPT Presentation

Displaced RPV SUSY & Baryogenesis

Yanou Cui

Perimeter Institute

Long-lived BSM particles @ LHC workshop UMass-Amherst, Nov 12, 2015

1

Displaced SUSY

• Gauge mediation: NLSP→gravitino + SM

decay suppressed by 1/F2, displaced with F≳104TeV

• Anomaly mediation: co-LSP winos

decay suppressed by mass degeneracy ∆m∼mᴨ ⇒long disappearing track

• Mini-split spectrum: NLSP→SM + LSP (RPC)

decay suppressed by 1/(m0)4 + 3-body

• R-parity violation: decay suppressed by tiny RPV

couplings (UDD, LLE, QDL…) (or w/mini-split spectrum)

2

Displaced SUSY

• Gauge mediation: NLSP→gravitino + SM

decay suppressed by 1/F2, displaced with F≳104TeV

• Anomaly mediation: co-LSP winos

decay suppressed by mass degeneracy ∆m∼mᴨ ⇒long disappearing track

• Mini-split spectrum: NLSP→SM + LSP (RPC)

decay suppressed by 1/(m0)4 + 3-body

• R-parity violation: decay suppressed by tiny RPV

couplings (UDD, LLE, QDL…) (or w/mini-split spectrum)

2

• Generically motivated by cosmology: baryogenesis!

Displaced SUSY

• Gauge mediation: NLSP→gravitino + SM

decay suppressed by 1/F2, displaced with F≳104TeV

• Anomaly mediation: co-LSP winos

decay suppressed by mass degeneracy ∆m∼mᴨ ⇒long disappearing track

• Mini-split spectrum: NLSP→SM + LSP (RPC)

decay suppressed by 1/(m0)4 + 3-body

• R-parity violation: decay suppressed by tiny RPV

couplings (UDD, LLE, QDL…) (or w/mini-split spectrum)

2

• Generically motivated by cosmology: baryogenesis!

(see Brock’s talk for more!)

Cosmological Concern with RPV Natural SUSY

3

Cosmological Concern with RPV Natural SUSY

3

• Light stop with RPV ( ) prompt decay: An important

channel of natural SUSY search at the LHC prompt ⇒ λij ≳10-7 (Ldecay ≳1 mm)

• f ◆

B natural

Cosmological Concern with RPV Natural SUSY

3

• f ◆

B natural

∗

B ˜ Hut ! ¯ di ¯ dj

• Assume conventional baryogenesis at T≳TEW

pre-existing baryon abundance efficiently erased by scatterings, e.g. ,, if λij ≳10-7 !

• Light stop with RPV ( ) prompt decay: An important

channel of natural SUSY search at the LHC prompt ⇒ λij ≳10-7 (Ldecay ≳1 mm)

• f ◆

B natural

Cosmological Concern with RPV Natural SUSY

3

• f ◆

B natural

∗

B ˜ Hut ! ¯ di ¯ dj

• Assume conventional baryogenesis at T≳TEW

pre-existing baryon abundance efficiently erased by scatterings, e.g. ,, if λij ≳10-7 !

• Light stop with RPV ( ) prompt decay: An important

channel of natural SUSY search at the LHC prompt ⇒ λij ≳10-7 (Ldecay ≳1 mm)

• f ◆

B natural

Cosmological Concern with RPV Natural SUSY

3

• f ◆

B natural

∗

B ˜ Hut ! ¯ di ¯ dj

• Assume conventional baryogenesis at T≳TEW

pre-existing baryon abundance efficiently erased by scatterings, e.g. ,, if λij ≳10-7 !

• Light stop with RPV ( ) prompt decay: An important

channel of natural SUSY search at the LHC prompt ⇒ λij ≳10-7 (Ldecay ≳1 mm)

• f ◆

B natural

YB(0) = Y ini

B e− R Tini

ΓW(T) H(T) dT T ⇠ Y init

B e −

λ2 ij y2 t g1/2 ∗ Mpl mEW

★ Estimate of washout: exponential reduction if Γw ≳ H (TEW)

Cosmological Concern with RPV Natural SUSY

3

• f ◆

B natural

∗

B ˜ Hut ! ¯ di ¯ dj

• Assume conventional baryogenesis at T≳TEW

pre-existing baryon abundance efficiently erased by scatterings, e.g. ,, if λij ≳10-7 !

• Light stop with RPV ( ) prompt decay: An important

channel of natural SUSY search at the LHC prompt ⇒ λij ≳10-7 (Ldecay ≳1 mm)

• f ◆

B natural

YB(0) = Y ini

B e− R Tini

ΓW(T) H(T) dT T ⇠ Y init

B e −

λ2 ij y2 t g1/2 ∗ Mpl mEW

★ Estimate of washout: exponential reduction if Γw ≳ H (TEW)

Cosmological Concern with RPV Natural SUSY

3

• f ◆

B natural

∗

B ˜ Hut ! ¯ di ¯ dj

• Assume conventional baryogenesis at T≳TEW

pre-existing baryon abundance efficiently erased by scatterings, e.g. ,, if λij ≳10-7 !

• Light stop with RPV ( ) prompt decay: An important

channel of natural SUSY search at the LHC prompt ⇒ λij ≳10-7 (Ldecay ≳1 mm)

• f ◆

B natural

YB(0) = Y ini

B e− R Tini

ΓW(T) H(T) dT T ⇠ Y init

B e −

λ2 ij y2 t g1/2 ∗ Mpl mEW

★ Estimate of washout: exponential reduction if Γw ≳ H (TEW)

What are possible solutions to this problem?

Avoid the Problem: Suppress RPV Washout

4

• To ensure successful baryogenesis at T≳TEW … (?)

Natural SUSY with λij ≲10-7 ⇒ Displaced Stop at LHC!

(Barry, Graham and Rajendran 2013)

CMS dijet ATLAS µ spect

charged stable

ATLAS HCAL t ! d s (RPV) ~ _ _

prompt paired dijets

jet substructure (projection)

C M S d i j e t ATLAS µ spect

• j

• n

charged stable

ATLAS HCAL t ! b b (DRPV) ~ _ _

prompt paired dijets jet substructure (projection)

ATLAS µ+tracks

★ Good coverage up to m∼1TeV w/recent development at

ATLAS/CMS! (colored, low bkg)

Liu and Tweedie, 2015

Solve the Problem: Baryogenesis from RPV

5

• Baryogenesis at T≲TEW , after all washout processes

decouple (Γw ≲ H ) ? — RPV reset/regenerate ΩB !? (new ideas…)

Solve the Problem: Baryogenesis from RPV

5

• Baryogenesis at T≲TEW , after all washout processes

decouple (Γw ≲ H ) ? — RPV reset/regenerate ΩB !? (new ideas…)

• Could SUSY shed light on prominent

puzzles in modern cosmology?

ΩDM ≈23%, ΩB≈5% , ΩB ~ ΩDM

• Familiar/well-studied case: (RPC) LSP

WIMP dark matter, MET+X search @LHC

p p MET MET χDM χDM ISR

Solve the Problem: Baryogenesis from RPV

5

• Baryogenesis at T≲TEW , after all washout processes

decouple (Γw ≲ H ) ? — RPV reset/regenerate ΩB !? (new ideas…)

• Could SUSY shed light on prominent

puzzles in modern cosmology?

ΩDM ≈23%, ΩB≈5% , ΩB ~ ΩDM

• Familiar/well-studied case: (RPC) LSP

WIMP dark matter, MET+X search @LHC

p p MET MET χDM χDM ISR

• Potential addressing ΩB, ΩB ~ ΩDM w/RPV?

⟹ (again) Displaced vertices @LHC!

6

Let’s start a journey beyond SUSY, then come back…

Mini-Review of Baryogenesis

6

Let’s start a journey beyond SUSY, then come back…

• Origin of ΩB ? = Where do we ourselves come from?

10 B ¯

B Initial asymmetry

⇡ ηB = (nB n ¯

B)/nγ ⇠ 1010

symmetric component annihilated away

Asymmetric ΩB today

Mini-Review of Baryogenesis

6

Let’s start a journey beyond SUSY, then come back…

• Origin of ΩB ? = Where do we ourselves come from?

10 B ¯

B Initial asymmetry

⇡ ηB = (nB n ¯

B)/nγ ⇠ 1010

symmetric component annihilated away

Asymmetric ΩB today

Sakharov Conditions (1967):

• Baryon number violation
• C-, CP-violation

(- provided by RPV SUSY ?…)

• Out-of equilibrium (CPT)

B

neq

B = neq ¯ B ,

hBieq = 0

Mini-Review of Baryogenesis

6

Let’s start a journey beyond SUSY, then come back…

• Origin of ΩB ? = Where do we ourselves come from?

10 B ¯

B Initial asymmetry

⇡ ηB = (nB n ¯

B)/nγ ⇠ 1010

symmetric component annihilated away

Asymmetric ΩB today

Sakharov Conditions (1967):

• Baryon number violation
• C-, CP-violation

(- provided by RPV SUSY ?…)

• Out-of equilibrium (CPT)

B

neq

B = neq ¯ B ,

hBieq = 0

ΩB ≈5%: Need BSM Physics!

Mini-Review of Baryogenesis

6

Let’s start a journey beyond SUSY, then come back…

• Origin of ΩB ? = Where do we ourselves come from?

10 B ¯

B Initial asymmetry

⇡ ηB = (nB n ¯

B)/nγ ⇠ 1010

symmetric component annihilated away

Asymmetric ΩB today

❖ Existing baryogenesis mechanisms: (leptogenesis, EWBG…) Most involve high M or/and T, direct experimental test impossible (c.f. WIMP DM for ΩDM)

Sakharov Conditions (1967):

• Baryon number violation
• C-, CP-violation

(- provided by RPV SUSY ?…)

• Out-of equilibrium (CPT)

B

neq

B = neq ¯ B ,

hBieq = 0

ΩB ≈5%: Need BSM Physics!

Baryogenesis from Out-of-Equilibrium Decay

A general class of baryogenesis models(e.g. leptogenesis)

• Assume a massive neutral particle χ
• Baryon asymmetry can be produced in its decay (B-, CP-violating)
• Typically, the inverse processes efficiently erase the asymmetry
• But, if χ is long-lived, and decays only after Tf < Mχ :

Out-of-equilibrium decay Sakharov conditions

Γ(χ ! f) 6= Γ(χ ! ¯ f) nf n ¯

f 6= 0

χ

f f

✔

χ

f f

13

X

e−Mχ/Tdecay

Inverse decay: Boltzmann suppressed

, X

7

Baryogenesis from Out-of-Equilibrium Decay

• Asymmetry is robustly preserved if (H: Hubble expansion rate)

Weak washout scenario An intriguing observation (YC, Sundrum 2012; YC, Shuve, 2014)

• If χ has mass at weak scale (the new energy frontier LHC

is exploring!), numerology gives

• Converting to decay length:

Γχ < H(T = Mχ),

χ

f f

✔

χ

f f

13

X

cτχ & mm

Displaced vertex regime @LHC!

8

c⌧ −1

χ

< H(TEW) ∼ 10−13 GeV

9

Γχ < H(T = Mχ),

cτχ & mm

• A generic connection between cosmological slow

rates at T ~100 GeV and displaced vertices at colliders

Displaced Vertices Motivated by Baryogenesis

• The universe around EW phase transition was just

slightly bigger than LHC tracking resolution!

H(100 GeV) ∼ 10−14 GeV ∼ (1.3 cm)−1

10 GeV → (1.3 m)−1

1 TeV → (0.13 mm)−1

Displaced Vertices Motivated by Baryogenesis

• Production at the LHC?

No conflict between a small decay rate and a large production rate

j/`/MET j/`/MET

p p

(cτχ & 1 mm)

χ

χBG

• Long lifetime due to

approximate symmetry (e.g. Z2 parity)

• Recover MET signal for

DM in the limit of exact symmetry!

10

Displaced Vertices Motivated by Baryogenesis

• Production at the LHC?

No conflict between a small decay rate and a large production rate

j/`/MET j/`/MET

p p

(cτχ & 1 mm)

χ

χBG

parity-preserving vertex

• Long lifetime due to

approximate symmetry (e.g. Z2 parity)

• Recover MET signal for

DM in the limit of exact symmetry!

10

Displaced Vertices Motivated by Baryogenesis

• Production at the LHC?

No conflict between a small decay rate and a large production rate

j/`/MET j/`/MET

p p

(cτχ & 1 mm)

χ

χBG

parity-preserving vertex parity-violating vertex

• Long lifetime due to

approximate symmetry (e.g. Z2 parity)

• Recover MET signal for

DM in the limit of exact symmetry!

10

Displaced Vertices Motivated by Baryogenesis

• Production at the LHC?

No conflict between a small decay rate and a large production rate

j/`/MET j/`/MET

p p

(cτχ & 1 mm)

χ

χBG

parity-preserving vertex parity-violating vertex

• Long lifetime due to

approximate symmetry (e.g. Z2 parity)

• Recover MET signal for

DM in the limit of exact symmetry!

10

Concrete, motivated baryogenesis models as example?

Baryogenesis from WIMPs

• YC and Raman Sundrum, Phys.Rev.D,11603 (2012)
• YC, JHEP 1312 (2013) 067

11

12

12

WIMP DM 𝜓 WIMP DM 𝜓 X X

• The familiar story of a stable WIMP

12

WIMP DM 𝜓 WIMP DM 𝜓 X X

ΩDM

• The familiar story of a stable WIMP

thermal freeze out

• ut-of-equilibrium

12

WIMP DM 𝜓 WIMP DM 𝜓 X X

ΩDM

• The familiar story of a stable WIMP

thermal freeze out

• ut-of-equilibrium
• A different story of a (general) WIMP?

WIMP 𝜓 WIMP 𝜓 X X

thermal freeze out

• ut-of-equilibrium

Stable 𝜓DM, ΩDM

?

12

WIMP DM 𝜓 WIMP DM 𝜓 X X

ΩDM

• The familiar story of a stable WIMP

thermal freeze out

• ut-of-equilibrium
• A different story of a (general) WIMP?

WIMP 𝜓 WIMP 𝜓 X X

thermal freeze out

• ut-of-equilibrium

Stable 𝜓DM, ΩDM Metastable 𝜓B?

(later decay)

?

+ B-, C-, CP-violating decay

✴ Diverse lifetimes: generic in nature

(symmetry, mass/coupling hierarchy) e.g. long lifetime of b-quark, muon ( ), SUSY WIMP w/RPV

mW mb, mµ

12

WIMP DM 𝜓 WIMP DM 𝜓 X X

ΩDM

• The familiar story of a stable WIMP

thermal freeze out

• ut-of-equilibrium
• A different story of a (general) WIMP?

WIMP 𝜓 WIMP 𝜓 X X

thermal freeze out

• ut-of-equilibrium

Stable 𝜓DM, ΩDM Metastable 𝜓B?

(later decay)

?

+ B-, C-, CP-violating decay

✴ Diverse lifetimes: generic in nature

(symmetry, mass/coupling hierarchy) e.g. long lifetime of b-quark, muon ( ), SUSY WIMP w/RPV

mW mb, mµ

YC and Sundrum 2012; YC 2013

• CP
• B(
• L)
• SM

SM

• SM

SM

• SM

T T

ΩB = ✏CP

Mp MWIMPΩτ!1 WIMP

WIMPΩτ!1

WIMP

★ Thermal freezeout ★ Baryogenesis

from decay

• A new baryogenesis mechanism

w/weak scale new physics: A WIMP miracle for baryons, can occur well below TEW

• If + A stable WIMP DM

new path addressing ΩB ~ ΩDM

• A generalized WIMP miracle!

Γχ . H(Tfreezeout)

13

Baryogenesis from Metastable WIMP Decay

A Minimal Model Example

(easy embedding in RPV natural SUSY!)

• We add to the Standard Model Lagrangian ( ):

di-quark scalar w/same charges as SM u-quark; SM singlet Majorana fermions; small breaking of a -parity long-lived

14

• nly χ

! SM

• nly χ

.

• B,
• CP

∆L = λijφdidj + εiχ¯ uiφ + M2

χχ2 + yiψ¯

uiφ + M2

ψψ2

+ αχ2S + β|H|2S + M2

SS2 + h.c.

φ: u; χ, ψ: SM Complex

χ ⌘ χB, the WIMP parent for baryogenesis. parameters leading to long-lived , can represent

• genesis. εi ⌧ 1:

represent a

S: singlet scalar, mediate WIMP annihilation via h-portal

A Minimal Model Example

• Out-of-equilibrium decay
• f 𝜓 ΩB
• Interference of tree- & loop-level decay

CP asymmetry

• Check other constraints ( oscillation, neutron EDM…)

With weak scale masses, new particles couple mostly

to heaviest quarks (b, t) (just like the Higgs boson!)

15

✏CP ≡ Γ( → ∗u) − Γ( → ¯ u) Γ( → ∗u) + Γ( → ¯ u)

χ ui φ ψ uj φ∗

χ φ uj ψ ui φ∗

Pn→¯

n

χ u φ∗ d d

¯ u φ ¯ d ¯ d χ

• Our mechanism: generic low scale baryogenesis

Embed in motivated theory framework, e.g. SUSY? Favored viable SUSY models after LHC runs:

• “Natural” SUSY: light stop and/or B-(L-) violation
• (Mini-)Split SUSY (mgauginos ≪ msfermions)

16

Meeting Particle Physics Frontier

—Embedding in Supersymmetry (SUSY)

V) m˜

t ⌧ m˜ q1,2

Coming back to RPV SUSY vs. baryogenesis…

Embedding in Natural SUSY: Model

Our minimal model: direct “blueprint”

• Promote singlets to chiral superfields, add to the MSSM.

superpotential:

• Assume pattern: scalar and heavy, decoupled,

as in “natural SUSY”

• Mapping: (minimal model SUSY model)
• Diquark light in superfield
• Baryon parent singlet fermion singlet
• Majorana MSSM gaugino
• Singlet scalar singlet , mixes with , enables

annihilation

• Small parameter , enables late decay via

mixing

¯ B ◆ B

lueprint”: our minimal singlets χ, S to ant super

• MSSM. Relevant superpotential terms:

W ⊃ λijTDiDj + ε0χHuHd + ytQHuT + +µχχ2 + µHuHd + µSS2 + αχ2S + βSHuHd.

Assume ⇠⇠⇠

⇠

SUSY patter

• f χ and

“natur and ˜ q1,2 al SUSY” Diquark φ light ˜ tR

• f super

⇒ superfield T,

ε0χH

ana ψ B and

ε0χH

2S 2S

− ˜ Hu mixing. of χ and

“natur

ε0

ε0:

y χ → ˜ ¯ tt

via χ − ˜ Hu

17

Embedding in Mini-Split SUSY

(Cui, JHEP 1312 (2013) 067)

Sakharov#1: out-of equilibrium

Split SUSY+ O(1) RPV: Natural long life-time of gauginos

Split spectrum Late decay automatic! e.g. (heavy mediator, 3- body...)

18

• SC

⇠

• O(100 1000)TeV ⇠ mscalar mgaugino ⇠ TeV

m 100 1000 TeV

+ RPV

χ → udd

2 X

Interesting (surprising) finding: successful baryogenesis from minimal SUSY standard model (WIMP decay)!

˜ B ˜ B → ∆B !

˜ B di dj uk ˜ d∗

Embedding in Mini-Split SUSY

(Cui, JHEP 1312 (2013) 067)

Sakharov#1: out-of equilibrium

Split SUSY+ O(1) RPV: Natural long life-time of gauginos

Split spectrum Late decay automatic! e.g. (heavy mediator, 3- body...)

18

• SC

⇠

• O(100 1000)TeV ⇠ mscalar mgaugino ⇠ TeV

m 100 1000 TeV

+ RPV

χ → udd

2 X

Interesting (surprising) finding: successful baryogenesis from minimal SUSY standard model (WIMP decay)!

! , m ˜

B

˜ B ˜ B → ∆B !

˜ B di dj uk ˜ d∗

★ Sakharov #2, #3 (CP-, B/L-violation)

rich CPV sources in SUSY (e.g. Majorana gaugino

masses), from RPV couplings (safer w/heavy scalars)

★ WIMP parent for baryons with “would-be” over-

abundance : Bino ! (not desirable if it is DM in RPC

SUSY...)

★ Nanopoulos-Weinberg Theorem for Baryogenesis:

additional source in the interference loop Another Majorana fermion in MSSM? , !

19

Embedding in Mini-Split SUSY

, ◆ B (◆ L) 100 1000

X

eV ˜ BB

• ¯

B ◆ B

˜ W,

, ˜ g

X

X

Minimal model (MSSM+RPV) gives everything needed for baryogenesis!

Embedding in Mini-split SUSY

20

˜ B di dj uk ˜ d∗

˜ B ˜ d di ¯ d ˜ g ˜ d∗ dj uk

˜ B ˜ B H H∗ ˜ H

Tree-level RPV decay: Interference loop: Thermal annihilation:

• Key processes:

˜ B dj di uk ˜ d∗ ¯ d ˜ d∗ ˜ g

(b)

(RPC decays also included in analysis)

Numerical Results, examples

Include cosmological constraints: … mini-split: !

104 105 106 107 106 107 108 109 m0 HGeVL m HGeV<

Baryogenesis with MB

0.01<WDB<0.04 washout Td>Tf

(a)

105 106 107 108 107 108 109 1010 m0 HGeVL m HGeV<

Leptogenesis with MB

0.01<WDB<0.04 washout Td>Tf Td<Tc

(b) Figure 7: Cosmologically allowed regions of parameter space for (a) baryogenesis and (b) leptogenesis models. We set RPV couplings λ

2 . Cyan region provides baryon abundance 10−2 < Ω∆B < 4·10−2.

In the case of leptogenesis the brown region is excluded by decay after EWPT at Tc ≈ 100 GeV. The pink region is excluded by our simple basic assumption that bino decays after freezeout. Yellow region is excluded by requiring that washout processes are suppressed (Td < M ˜

B). Yellow region is in fact all included in the

pink region (so appear to be orange in the overlapped region).

! mscalar ⇠ O(100 1000)TeV M n i 2 m2 M f Ω∆B,

Loss of full naturalness: a compromise with anthropic/ environmental selection?

21

Baryogenesis from Out-of-equlibrium Decays

— Collider Phenomenology

YC and Shuve, arxiv:1409.6729, JHEP

★ Strategy/results generally applicable to other new physics search via displaced vertices

22

• Classify parity-invariant production modes (analogy to DM

search @LHC!), e.g.

• Classify decay modes (unlike DM search), e.g.

Simplified Models

23

• Classify parity-invariant production modes (analogy to DM

search @LHC!), e.g.

• Classify decay modes (unlike DM search), e.g.

wino/gluino-like (state in interference loop) Charged under SM gauge interactions:

g/W/Z

χ

χ

Simplified Models

23

• Classify parity-invariant production modes (analogy to DM

search @LHC!), e.g.

• Classify decay modes (unlike DM search), e.g.

wino/gluino-like (state in interference loop) Charged under SM gauge interactions:

g/W/Z

χ

χ

Simplified Models

Higgs portal:

singlet-like (e.g. Mχ = 150 GeV)

χ

χ

h

S

sin α

λSχχ

23

• Classify parity-invariant production modes (analogy to DM

search @LHC!), e.g.

• Classify decay modes (unlike DM search), e.g.

wino/gluino-like (state in interference loop) Charged under SM gauge interactions:

g/W/Z

χ

χ

Simplified Models

Higgs portal:

singlet-like (e.g. Mχ = 150 GeV)

χ

χ

h

S

sin α

λSχχ

fixed coupling,
 study mass reach fix mass, study
 coupling reach

23

• Classify parity-invariant production modes (analogy to DM

search @LHC!), e.g.

• Classify decay modes (unlike DM search), e.g.

wino/gluino-like (state in interference loop) Charged under SM gauge interactions:

g/W/Z

χ

χ

Simplified Models

Higgs portal:

singlet-like (e.g. Mχ = 150 GeV)

χ

χ

h

S

sin α

λSχχ

fixed coupling,
 study mass reach fix mass, study
 coupling reach

Baryon number violating:

χ → uidjdk

23

• Classify parity-invariant production modes (analogy to DM

search @LHC!), e.g.

• Classify decay modes (unlike DM search), e.g.

wino/gluino-like (state in interference loop) Charged under SM gauge interactions:

g/W/Z

χ

χ

Simplified Models

Higgs portal:

singlet-like (e.g. Mχ = 150 GeV)

χ

χ

h

S

sin α

λSχχ

fixed coupling,
 study mass reach fix mass, study
 coupling reach

Baryon number violating:

χ → uidjdk

Lepton number violating:

χ → LiQj ¯ dk

χ → LiLj ¯ Ek

23

• Classify parity-invariant production modes (analogy to DM

search @LHC!), e.g.

• Classify decay modes (unlike DM search), e.g.

wino/gluino-like (state in interference loop) Charged under SM gauge interactions:

g/W/Z

χ

χ

Simplified Models

Higgs portal:

singlet-like (e.g. Mχ = 150 GeV)

χ

χ

h

S

sin α

λSχχ

fixed coupling,
 study mass reach fix mass, study
 coupling reach

Baryon number violating:

χ → uidjdk

Lepton number violating:

χ → LiQj ¯ dk

χ → LiLj ¯ Ek

23

Later comprehensive analyses in RPV SUSY: Liu, Tweedie 2015; Csaki et.al 2015; Zwanne 2015

Experimental Searches

• Focus on displaced decay in tracking volume
• Near lower bound & better sensitivity, easier to model!

(decay in other parts of detector important too…)

cτχ & mm

24

Experimental Searches

• Focus on displaced decay in tracking volume
• Near lower bound & better sensitivity, easier to model!

(decay in other parts of detector important too…)

• Two concrete examples (light-flavour only):

Baryon number violating: displaced jets (all-hadronic)

CMS, arXiv:1411.6530

χ → 3q

cτχ & mm

24

Experimental Searches

• Focus on displaced decay in tracking volume
• Near lower bound & better sensitivity, easier to model!

(decay in other parts of detector important too…)

• Two concrete examples (light-flavour only):

Baryon number violating: displaced jets (all-hadronic)

CMS, arXiv:1411.6530

χ → 3q

Lepton number violating: displaced muon + hadrons

ATLAS-CONF-2013-092

→ ` + 2q

cτχ & mm

24

Experimental Searches

• Focus on displaced decay in tracking volume
• Near lower bound & better sensitivity, easier to model!

(decay in other parts of detector important too…)

• Goal of our analysis:
• What is the coverage for our simplified models based on

benchmarks chosen by the collaborations?

• What advice can we provide for general experimental improvement?

• Two concrete examples (light-flavour only):

Baryon number violating: displaced jets (all-hadronic)

CMS, arXiv:1411.6530

χ → 3q

Lepton number violating: displaced muon + hadrons

ATLAS-CONF-2013-092

→ ` + 2q

cτχ & mm

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Fully hadronic displaced vertices

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8 TeV:

200 400 600 800 1000 0.5 1.0 5.0 10.0 50.0 100.0 Mc HGeVL scc95 % CL HfbL

wino Æ 3j, s = 8 TeV

scc HNLOL <Lxy> = 300 cm <Lxy> = 30 cm <Lxy> = 3 cm

wino

CMS displaced dijet, arXiv:1411.6530

Fully hadronic displaced vertices

25

8 TeV:

200 400 600 800 1000 0.5 1.0 5.0 10.0 50.0 100.0 Mc HGeVL scc95 % CL HfbL

wino Æ 3j, s = 8 TeV

scc HNLOL <Lxy> = 300 cm <Lxy> = 30 cm <Lxy> = 3 cm

wino

singlet-like (Higgs portal)

No bound @ 8 TeV 20 fb-1! (we study a challenging case: Mχ = 150 GeV, moderately off-shell!) CMS displaced dijet, arXiv:1411.6530

Fully hadronic displaced vertices

25

8 TeV:

200 400 600 800 1000 0.5 1.0 5.0 10.0 50.0 100.0 Mc HGeVL scc95 % CL HfbL

wino Æ 3j, s = 8 TeV

scc HNLOL <Lxy> = 300 cm <Lxy> = 30 cm <Lxy> = 3 cm

wino

singlet-like (Higgs portal)

No bound @ 8 TeV 20 fb-1! (we study a challenging case: Mχ = 150 GeV, moderately off-shell!) CMS displaced dijet, arXiv:1411.6530

0.5 1.0 1.5 2.0 10 20 50 100 200 500 1000 2000 lScc sinH2aL luminosity Hfb-1L

Higgs portal c Æ 3j, 1DV vs. 2DV comparison s = 13 TeV

mc = 150 GeV 1 DV, 30% syst. 1 DV, 10% syst. 2 DV

Lxy = 3 cm

1000 1500 2000 2500 1 5 10 50 100 500 1000 Mc HGeVL luminosity Hfb-1L

wino Æ 3j, 2 DV, luminosity for 3 events, s = 13 TeV

1 DV, 30% syst. 1 DV, 10% syst. 2 DV

13 TeV:

Displaced muon + hadrons

26

wino

200 400 600 800 0.5 1.0 5.0 10.0 50.0 100.0 Mc HGeVL scc95 % CL HfbL

wino Æ m + tracks, s = 8 TeV

scc HNLOL <Lxy> = 30 cm <Lxy> = 3 cm <Lxy> = 0.3 cm

500 1000 1500 2000 2500 0.001 0.01 0.1 1 10 100 1000 Mc HGeVL luminosity Hfb-1L

wino Æ m + tracks, 1 DV, luminosity for 3 events, s = 13 TeV

<Lxy> = 30 cm <Lxy> = 3 cm <Lxy> = 0.3 cm

8 TeV 13 TeV:

M~2.5 TeV

ATLAS-CONF-2013-092

Displaced muon + hadrons

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wino

200 400 600 800 0.5 1.0 5.0 10.0 50.0 100.0 Mc HGeVL scc95 % CL HfbL

wino Æ m + tracks, s = 8 TeV

scc HNLOL <Lxy> = 30 cm <Lxy> = 3 cm <Lxy> = 0.3 cm

500 1000 1500 2000 2500 0.001 0.01 0.1 1 10 100 1000 Mc HGeVL luminosity Hfb-1L

wino Æ m + tracks, 1 DV, luminosity for 3 events, s = 13 TeV

<Lxy> = 30 cm <Lxy> = 3 cm <Lxy> = 0.3 cm

8 TeV 13 TeV:

M~2.5 TeV

singlet (Higgs portal)

No bound @ 8 TeV 20 fb-1

0.0 0.5 1.0 1.5 2.0 5 10 50 100 500 1000 lScc sinH2aL luminosity Hfb-1L

Higgs portal c Æ m + tracks, 1DV, luminosity for 3 events, s = 13 TeV

mc = 150 GeV <Lxy> = 30 cm <Lxy> = 3 cm <Lxy> = 0.3 cm

(singlet-like, Mχ = 150 GeV) ATLAS-CONF-2013-092

• 13 TeV: 𝞃S~10 ab for Lxy~1 cm!

Conclusion/Outlook-1

• A general conflict between RPV natural SUSY with

prompt decay vs. conventional baryogenesis at T≳TEW

• Passive solution: suppress RPV ⟹ displaced stop

(good coverage)

• Natural alternative: (new) baryogenesis at T≲TEW
• WIMP baryogenesis (ΩB (+)ΩB ~ ΩDM) & RPV SUSY

⟹ displaced singlino/wino (sample high multiplicity DV,

improve trigger/sensitivity for all-hadronic final states…)

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Conclusion/Outlook-2

• Baryogenesis from metastable weak scale particle

decay:

• A robust cosmological motivation for DV searches

at the LHC

• Exciting opportunity to reproduce the early universe

BG @LHC! (cf. WIMP DM search)

• w/ATLAS displaced jets working group: working on

implementing our simplified models as a benchmark example in official analysis w/LHC Run 2 data…

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