PINS, slac, July 16th 2019

Neutrino massFrom cosmology

Jia LiuNSF Fellow

Image credit: Tom Abel & Ralf Kaehler (KIPAC, SLAC)

Neutrino Oscillation ImpliesNeutrinos Must Have Mass

Normal InvertedΣmν>0.06 eV Σmν>0.1 eV

?0

Neutrino Mass from Oscillation Experiments

m2

2.5⨉10-3eV2Atmospheric / beam:

SK, MINOS, NOvA, T2K, IceCube

7.6⨉10-5eV2Solar:

SNO, KamLAND, Borexino

ν

3ν

2

ν1

ν3

ν2

ν1

Standard Model

Fermions

1012eV

109eV

106eV

103eV

1 eV

10-3eV

10-6eV

Mass generation mechanism?

CP Violation &Matter-antimatter asymmetry?

Do RH neutrinos exist?

CP Violation &Matter-antimatter asymmetry?

CP Violation &Matter-antimatter asymmetry?

Current Constraints

Electron kinetic Energy

Eve

nt C

ount

s

* 0νββ experiments (KamLAND-Zen, GERDA, etc.) are also sensitive to neutrino mass

-

Particle Experiments: Tritium Beta Decay

End pointmν = 0

End pointmν > 0

18keV

Current Constraints (95% CL)Minimum mass: 0.06 eV (Normal), 0.1 eV (Inverted)

Particle experiment Troitsk beta decay (Assev+2011)

mνeeff < 2 eV

KATRIN projection: 0.2 eV

Cosmology CMB, CMB Lensing, BAO (Planck 2018)

Σmν < 0.12 eVLSST+DESI+CMB-S4 forecast: 0.03 eV

2018-2023 2022-2019-

~2027-

Cosmic Neutrinos

CMB :380,000 yrs after

the Big Bang

CMB :380,000 yrs after

the Big Bang

C𝝂B :One second after

the Big Bang

CMB :380,000 yrs after

the Big Bang

C𝝂B :One second after

the Big Bang

?

IceCube collaboration / NSF / University of Wisconsin

Cosmic 𝝂.Difficult to detect due to their low energy

PTOLEMY ExperimentPrinceton Tritium Observatory for Light, Early-Universe, Massive-Neutrino Yield

PTOLEMY ExperimentPrinceton Tritium Observatory for Light, Early-Universe, Massive-Neutrino Yield

Our Universe as the “Detector”

Structure Formation

Microwave sky seen by COBE

Extremely smooth density field

380,000 years after the Big Bang (z=1100)

Galaxy distribution measured by 2dF

Structures (galaxies, clusters) formed

Today

Structure Formation

Massive Cosmic Neutrinos Suppress the Growth of Structure

With large thermal velocities, cosmic neutrinos suppress structure growth below their free-streaming length (e.g. ~110 Mpc for 0.1eV).

Standard Model of Cosmology Massive Neutrinos

Credit: Katrin Heitmann

Massive Cosmic Neutrinos Suppress the Growth of Structure

How do we measure the suppression

in data?

Galaxy Density Map(Sloan Digital Sky Survey)

Two Point Correlation FunctionFourier Space: Power Spectrum

Measures clustering as a function of distance

Image: SDSS galaxies

Matter Power SpectrumCosmic Scale Cluster/Galaxy

Suppression due to

massive neutrinos

Neutrino Mass

Credit: Carlton Baugh

Galaxies: Biased Tracers of Matter Distribution

Weak Gravitational Lensing:Sensitive to the Total Matter Distribution

Weak Lensing of the CMB

UNLENSEDCr

edit:

Bla

ke S

herw

in

LENSEDCr

edit:

Bla

ke S

herw

in

Σmν in the Next Decade

Modeling Nonlinear Structure

Survey Systematics(photo-z, shape…)

AstrophysicalProcesses(Baryons, IA...)

Coordinating Joint Probes

Roadmap to pin down Σm𝜈

Modeling Nonlinear Structure

Survey Systematics(photo-z, shape…)

AstrophysicalProcesses(Baryons, IA...)

Coordinating Joint Probes

Modeling Nonlinear Structure Σm𝜈= 0.1eV

–– Linear Theory–– Nonlinear (Takahashi)–– Nonlinear (Bird)

Linear Regime:Analytical Linear Theory

Mildly Nonlinear:Perturbation Theory

Highly Nonlinear:Numerical

Simulations

Neutrino Effect

StrongestHere

10% errors in current nonlinear models(we need <1%!)

MassiveNuSCosmological Massive Neutrino SimulationsJia Liu et al 2018 (https://arxiv.org/abs/1711.10524)

Σm𝜈 (eV)Neutrino Mass

𝛀 m M

atter

Densit

y

As Primordial Clustering Amplitude

Each of the 100 points is a high resolution simulation

(2 million core hours in total)

Modeling Nonlinear Structure

Survey Systematics(photo-z, shape…)

AstrophysicalProcesses(Baryons, IA...)

Coordinating Joint Probes

Modeling Nonlinear Structure

Survey Systematics(photo-z, shape…)

Coordinating Joint Probes

AstrophysicalProcesses(Baryons, IA...)

Dark matter Baryons

Illustris simulation

Modeling Nonlinear Structure

Survey Systematics(photo-z, shape…)

AstrophysicalProcesses(Baryons, IA...)

Coordinating Joint Probes

18,000 deg2

8.4m ugrizy

15,000 deg2 1.2m Optical/NIR

2,200 deg2(deep)2.4m NIR

16,000 deg2 1𝜇K-arcmin

28-230GHz(?)

16,000 deg2 6𝜇K-arcmin27-280GHz

Upcoming CMB and Galaxy Surveys

LiteBIRD

Mishra-Sharma, Alonso, Dunkley 2018

CMB S4LSST Clustering

LSST Lensing

LSST

S4+LSST S4+DESIw

dark

ene

rgy

equa

tion

of s

tate

No experiment can do it alone

2021 2022 2023 2024 2025 2026 2027 2028 2029LSSTEuclid

WFIRSTSimons Observatory

CMB-S4

Galaxy CM

B

Massive NeutrinosSuppress the structure growth

Summary

Massless

Massive

Must Combe Multiple Cosmological Probes

Mishra-Sharma, Alonso, Dunkley 2018

CMB S4LSST Clustering

LSST Lensing

LSST

S4+LSST S4+DESI

w da

rk e

nerg

y eq

uatio

n of

st

ate