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Bhaskar DuttaTexas A&M University

Particle Theory Models and Dark Matter: A Status Update

October 31, 2017

Texas Tech University, Lubbock

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QuestionsSome Outstanding Issues of High Energy Theory

1. Dark Matter content ( is 27%)

2. Electroweak Scale

3. Ordinary Matter (baryon) Content ( is 5%)

4. Rapid Expansion of the Early Universe

5. Neutrino Mass and interactions...

Need: Theory, Experiment and Observation

DMΩ

bΩ

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Questions

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Current Status

Collider Experiments: LHCDirect Detection Experiments: DAMA, CDMS, XENON 100,

CoGeNT, LUX etc.Indirect Detection Experiments: Fermi, AMS, PAMELACosmic Microwave Sky: Planck, WMAPNeutrino Experiments: T2K, Daya Bay, Double CHOOZ,

RENO etc. COHERENT

What have we learnt? What is the status of theory models? What do we expect in the near future?Are we closing in?

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What have we learnt so far? LHC, Direct and Indirect Detection Experiments, Planck Data

Status of Models with DM Dark Matter: Cosmological History Dark Matter, Ordinary Matter Contents

Expectations Future Direct and Indirect Detection results Dark Matter at the LHC

Concluding Insights

Presentation Outline

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Large Hadron Collider(LHC)

Proton-Proton Collision

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Higgs Boson has been found Mass (mh) 125 GeVCompletes Standard Model

3 families of quarks, leptons, Gauge Bosons (force carriers) : W±, Z, γ, g

LHC: Higgs

Higgs mechanism breaks the SM symmetry spontaneously and generates mass for quarks, leptons, W, Z and Higgs

Symmetry breaking scale(Electroweak scale): 246 GeV

Much lower than the Planck scale: 1.22 x 1019 GeV

Mz=91.18 GeV, Mw=80.22 GeV

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• Higgs mass increases rapidly with scale mh2= m0

2+k Λ2: divergence problem solution needs fine tuning (1 part in 1032)

• SM prediction: mh<850 GeV to satisfy the unitarity in W scattering

• Fine tuning problem solved in supersymmetry due to fermions ↔ bosons symmetry

• Higgs mass predicted in SUSY Model?Minimal Supersymmetry Standard Model (MSSM):

loop correction prediction: mh<135 GeV

•Measured mass (125 GeV) appears in the tight MSSM window

LHC: Higgs

+= β2222 CosMm Zh Mz=91.18 GeV

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LHC: Supersymmetry

Most models predict: 1-3 TeV (colored particle masses)So far: No colored particle up to 1.9 TeV

Non-colored SUSY particles: 100 GeV to 1-2 TeV(Major role in the DM content of the Universe)

Weak LHC bound for non-colored particles hole in searches!

Trouble in Models with very tight correlation between colored and non-colored particles , e.g., minimal SUGRA/CMSSM

LHC + Direct Detection + Indirect Detection quite constraining

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Direct Detection Experiments

Any parameter space left?

DM

DM

CDMS, DAMA, CoGeNT:Signal for Low mass DM

LUX: No signal for Low or High DM mass

arXiv:1608.07648

Status of New physics/SUSY in the direct detection experiments:

• Astrophysical and nuclear matrix element uncertainties• No signal: some particle physics models are ruled out

Indirect Detection: Fermi

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: smaller than the thermal valueoannv ><σ

>< vannσ

Thermal DM 27%

Gamma-rays constraints: Dwarf spheroidals, Galactic center

Experimental constraints:

Fermi Collaboration: arXiv:1503.02641

LargeCross-sectionis constrained

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From Planck

http://public.planck.fr/images/resultats/2014-matiere-noire/plot_constraints_planck2014.jpg

Indirect Detection Excess of positrons has been found by both

AMS, PAMELA and Fermi

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Dark Matter Mass: More than 100 GeVTheory Models predictions: The excess will fall off

Pulsar can produce this excess

Is this excess due toDM annihilation?

Need Larger Cross-section (larger than the thermal cross-section 3x 10-26 cm3/sec)

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Probing Dark Matter

SM

Dark Energy68%

Atoms5%

Dark Matter27% +

Collider experiments

Overlapping region

DM content (CMB) + overlapping region:

Cosmological history, particle physics models, astrophysics

Summary

Direct Production at the collider: SUSY lurking around? More Higgs? New signal?

Direct Detection and LHC: Low/high mass DM particle?

Indirect Detection and LHC: DM thermal/non-thermal/multi-component?

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~ 0.0000001 seconds

Dark Matter: When?

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Now

Dark Matter: ThermalProduction of thermal non-relativistic DM:

particlesSMDMDM ⇔+

particlesSMDMDM ⇒+

Universe cools (T<mDM)

particlesSMDMDM ⇔+

Boltzmann equation

][3 2,

2eqDMDMeqDM

DM nnvHndt

dn−−=+ σ

∫

∫+−

+−

=

6

/)(2

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3

6

/)(2

31

3

)2(

)2(21

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π

πσ

σ TEE

TEE

eq epdpd

vepdpd

vvolnostppfdgn /.

)2(),(

3

3

≡= ∫ π

m/T

3* Tgn

snY

s

==Y

Dark Matter: Thermal

Freeze-Out: Hubble expansion dominates over the interaction rate

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v1~DM σρc

DMDM nm=Ω

20~ DM

fmT

Dark Matter content:

Assuming : 2

2

~vχ

χασmf

αχ~O(10-2) with mχ ~ O(100) GeVleads to the correct relic abundance

m/T

freeze out

scm3

26103v −×=σY becomes constant for T>Tf

Nc G

Hπ

ρ83 2

0=

Y

Y~10-11 for mχ~100 GeVto satisfy the DM content

Thermal Dark Matter

DM particle + DM Particle SM particles

Annihilation Cross-section Rate:

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>< vannσ

DM

DM

DM

DM

f: SM particles; h, H, A: various Higgs, : SUSY particleNote: All the particles in the diagram are colorless

v1~DM σ

Ω

DM Abundance:

f~

scm3

26103v −×=σWe need to satisfy thermal DM requirement

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Suitable DM Candidate: Weakly Interacting Massive Particle (WIMP)

Typical in Physics beyond the SM (LSP, LKP, …)

Most Common: Neutralino (SUSY Models)

Neutralino: Mixture of Wino, Higgsino and Bino

Neutralino can give rise to larger/smaller annihilation rate

Larger/Smaller Annihilation Non-thermal Models

Thermal Dark Matter

Thermal Dark Matter

Dark Energy68%

Atoms5%

Dark Matter27%

v1~DM σ

Ω

20~ DM

fmT

Dark Matter content:

Weak scale physics :

2

2

~vχ

χασmf

αχ~O(10-2) with mχ ~ O(100) GeVleads to the correct relic abundance

freeze out

scm3

26103v −×=σ

Mp

Inflation

TeV

GeV

MeVBBN

~ WIMP freeze-out

Non-standard thermal history at is generic in some explicit high Scale theories.

fTfTT >

Acharya, Kumar, Bobkov, Kane, Shao’08Acharya, Kane, Watson, Kumar’09Allahverdi, Cicoli, Dutta, Sinha,’13

Status of Thermal DMThermal equilibrium above is an assumption.

DM content will be different in non-standard thermal histories Barrow’82, Kamionkowski, Turner’90

DM will be a strong probe of the thermal history after it is discovered and a model is established.

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Non-Thermal DM

Decay of moduli/heavy field occurs at:

)MeV5(TeV100

~2/3

2/1

φmcTr

Tr ~ MeV : Not allowed by BBN

[Moduli : heavy scalar fields gravitationally coupled to matter]

>< vannσ : different from thermal average, is not 27% Non-thermal DM can be a solution

DM from the decay of heavy scalar field, e.g., Moduli decay

For Tr<Tf: Non-thermal dark matter

v1~DM σ

Ω

Decay of moduli produce both DM and ordinary matter

Moroi, Randall’99; Acharya, Kane, Watson’08,Randall; Kitano, Murayama, Ratz’08; Dutta, Leblond, Sinha’09; Allahverdi, Cicoli, Dutta, Sinha,’13Baer, Choi, Kim, Roszkowski’ 14 Mp

Inflatio

TeV

GeV

MeV

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Non-thermal DM

Non-thermal DM Production from moduli decay

Ordinary Matter and DM from moduli decay ⇒ Cladogenesis of DM and Ordinary Matter (Baryons) [Allaverdi, Dutta, Sinha’11]

Cladogenesis: is an evolutionary splitting event in a species in which each branch and its smaller branches forms a "clade", an evolutionary mechanism and a process of adaptive evolution that leads to the development of a greater variety of sister species.

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Mp

Inflation

TeV

GeV

MeVBBN

~ WIMP freeze-out

Mp

Inflation

TeV

GeV

MeVBBN

Non-thermal DM

Large multicomponent/non-thermal; Small Non-thermal

Probe directly at Indirect and Collider experiments

>< vannσ

DM content: summary

>< vannσ

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Future: Direct

Neutrino background seems to be a real problem!

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Neutrino background difficulties:

1. Measure the background very well in other experiments2. Measure the recoil spectrum to identify DM from neutrino

Future: Direct

1. Background is due to coherent scattering of solar and atmospheric neutrinos

Measure the coherent scattering: reactor (𝝂𝝂𝒆𝒆) and stopped pion sources (𝝂𝝂𝝁𝝁,𝝂𝝂𝝁𝝁, 𝝂𝝂𝒆𝒆)

Recent results: COHERENT (Science 03 Aug 2017)Future results: Miner, MINER+CONNIE : Texas A&M University

Determine the neutrino background carefully

2. Shape of the recoil spectra are different for different operators Identify neutrino from DM

Dent, Dutta, Newstead, Strigari, Walker, 2016

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Future: Indirect

DM+DM 𝑓𝑓 + 𝒇𝒇 𝟐𝟐𝑓𝑓 + 𝟐𝟐𝒇𝒇

b quark final states have the best constraints

Clark, Dutta, Strigari, arXiv:1709.07410

<σv>

cm

3 /s

MDM (GeV)

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Dark Matter at the LHC

Annihilation of lightest neutralinos (DM particles) quarks, leptons etc.At the LHC: proton + proton DM particles

DM Annihilation diagrams: mostly non-colored particlese.g., sleptons, staus, charginos, neutralinos, etc.

How do we produce these non-colored particles and the DM particle at the LHC? Can we measure the annihilation cross-section ?>< vannσ

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The signal : SM particles + DM particle(Missing energy)

Via Cascade decays at the LHC

(or l+l-, τ+τ−)DM

DMColored particles are produced and they decay finally into the weakly interacting stable particle

High PT jet

(or l+l-, τ+τ−)LHC is very complicated

DM at the LHC

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LHC has a blind spot for productions of non-colored particle

Special search strategy needed to extract the signal

The W boson (colorless) coming out of high energy protons can produce colorless particlesVector Boson Fusion(VBF)

New way of understanding DM or new physicssector at the LHC

Using a high ET jet + missing energy

Dutta, Gurrola, Kamon et al ’13,’14,’15,’16

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Cross Sections via VBFDM Via W at the LHCjjpp 0

10

1~~ χχ→

DM

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DM Content via VBF

Simultaneous fit of various observables:

How to check that LHC observations lead to correct dark matter content? Measure Ω at the LHC (Ω is 27%: Planck Measurement)

Dutta, Kamon etal, Phys.Rev.Lett. 111 (2013) 061801

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DM via jets +missing energy

CMS PAS EXO-16-048

Kunori et al

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Concluding InsightsModel ideas have constraints from LHC, Planck,

Neutrino data, direct and indirect detection constraints Higgs mass is within the supersymmetry model prediction

window Non-thermal Dark matter is well motivated Both Thermal and Non-thermal Dark matter have

allowed parameter spaceNon-thermal scenarios can allow us to understand the

Ordinary Matter-Dark Matter coincidence puzzleDetermination of the property of DM is crucial: LHC, direct and Indirect detections identify DM modelNeed to investigate colorless particles (suitable for DM

calculation), new force mediators at the LHC and in other experiments (e.g., Coherent neutrino scattering)

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Concluding Insights