NEUTRINO PHYSICS FROM - PowerPoint Presentation

Slide1

NEUTRINO PHYSICS FROM

COSMOLOGY

EVIDENCE FOR NEW PHYSICS?

STEEN

HANNESTAD, Aarhus UniversityNuHorizons 2011

ne nm ntSlide2

Fermion Mass Spectrum

10

100

1

10

100

1

10

100

1

10

100

1

10

100

1

1

meV

eV

keV

MeV

GeV

TeV

d

s

b

Q =

-

1/3

u

c

t

Q =

+

2/3

Charged Leptons

e

m

t

All flavors

n

3

NeutrinosSlide3

FLAVOUR STATES

PROPAGATION STATES

MIXING MATRIX (UNITARY)

FORTUNATELY WE ONLY HAVE TO

CARE ABOUT THE MASS STATESSlide4

Normal hierarchy

Inverted hierarchy

If neutrino masses are hierarchical then oscillation experiments

do not give information on the absolute value of neutrino masses

However, if neutrino masses are degenerateno information can be gained from such experiments.

Experiments which rely on either the kinematics of neutrino massor the spin-flip in neutrinoless double beta decay are the most efficient for measuring m0

SOLAR

n

KAMLAND

ATMO.

n

K2K

MINOSSlide5

LIGHTEST

INVERTED

NORMAL

HIERARCHICAL

DEGENERATESlide6

experimental observable is m

n

2

model independent neutrino mass from ß-decay kinematics

only assumption: relativistic energy-momentum relation

E0 = 18.6 keV

T1/2 = 12.3 y

ß-decay and neutrino mass

T2:Slide7

Tritium decay endpoint measurements have provided limits

on the electron neutrino mass

This translates into a limit on the sum of the three mass eigenstates

Mainz experiment, final analysis (Kraus et al.)Slide8

TLK

KATRIN experiment

Ka

rlsruhe

Tritium Neutrino Experiment at Forschungszentrum KarlsruheData taking starting

early 2012

25 mSlide9
Slide10

NEUTRINO MASS AND ENERGY DENSITY

FROM COSMOLOGY

NEUTRINOS AFFECT STRUCTURE FORMATIONBECAUSE THEY ARE A SOURCE OF DARK MATTER(

n ~ 100 cm-3

)HOWEVER, eV NEUTRINOS ARE DIFFERENT FROM CDM BECAUSE THEY FREE STREAM

SCALES SMALLER THAN dFS DAMPED AWAY, LEADS TOSUPPRESSION OF POWER ON SMALL SCALES

FROMSlide11

N-BODY SIMULATIONS OF

LCDM WITH AND WITHOUT NEUTRINO MASS (768 Mpc

3) – GADGET 2

T Haugboelle, University of Aarhus

256MpcSlide12

AVAILABLE COSMOLOGICAL DATASlide13

WMAP-7 TEMPERATURE POWER SPECTRUM

LARSON ET AL, ARXIV 1001.4635Slide14

LARGE SCALE STRUCTURE SURVEYS - 2dF AND SDSSSlide15

SDSS DR-7

LRG SPECTRUM(Reid et al ’09)Slide16

S

m =

0.3 eVFINITE NEUTRINO MASSES SUPPRESS THE MATTER POWERSPECTRUM ON SCALES SMALLER THAN THE FREE-STREAMING

LENGTH

Sm = 1 eVSm = 0

eVP(k)/P(k,mn

=0)Slide17

NOW, WHAT ABOUT NEUTRINO

PHYSICS?Slide18

WHAT IS THE PRESENT BOUND ON THE NEUTRINO MASS?

STH, MIRIZZI, RAFFELT, WONG (arxiv:1004:0695)

HAMANN, STH, LESGOURGUES, RAMPF & WONG (arxiv:1003.3999)DEPENDS ON DATA SETS USED AND ALLOWED PARAMETERS

USING THE MINIMAL COSMOLOGICAL

MODELTHERE ARE MANY ANALYSES IN THE LITERATURE

JUST ONE EXAMPLESlide19

THE NEUTRINO MASS FROM COSMOLOGY PLOT

Larger model

space

More data

CMB only

+ SDSS+ SNI-a

+WL

+Ly-alpha

MinimalLCDM

+

N

n

+

w

+……

1.1 eV

0.6 eV

~ 0.5 eV

~ 0.2 eV

~ 2 eV

2.? eV

??? eV

~ 1 eV

1-2 eV

0.5-0.6 eV

0.5-0.6 eV

0.2-0.3 eV

0.2-0.3 eVSlide20

Gonzalez-Garcia et al., arxiv:1006.3795Slide21

WHAT IS

Nn

?A MEASURE OF THE ENERGY DENSITY IN NON-INTERACTINGRADIATION IN THE EARLY UNIVERSE

THE STANDARD MODEL PREDICTION IS

BUT ADDITIONAL LIGHT PARTICLES (STERILE NEUTRINOS,AXIONS, MAJORONS,…..) COULD MAKE IT HIGHERMangano et al., hep-ph/0506164Slide22

TIME EVOLUTION OF

THE 95% BOUND ON

Nn

ESTIMATED PLANCKSENSITIVITY

Pre-WMAPWMAP-1

WMAP-3WMAP-5

WMAP-7Slide23

ASSUMING A NUMBER OF ADDITIONAL STERILE STATES OF

APPROXIMATELY EQUAL MASS, TWO QUALITATIVELY DIFFERENT

HIERARCHIES EMERGE

3+N

N+3

n

s

n

s

n

A

n

A

A STERILE NEUTRINO IS PERHAPS THE MOST OBVIOUS CANDIDATE

FOR AN EXPLANATION OF THE EXTRA ENERGY DENSITYSlide24

Hamann

, STH,

Raffelt, Tamborra,Wong, arxiv:1006.5276 (PRL)

COSMOLOGY AT PRESENTNOT ONLY MARGINALLY PREFERS EXTRA ENERGY

DENSITY, BUT ALSO ALLOWSFOR QUITE HIGH NEUTRINO MASSES!3+NN+3

See alsoDodelson et al. 2006Melchiorri et al. 2009Acero & Lesgourgues 2009Slide25

Updated Antineutrino mode MB results for E>475

MeV

(official oscillation region)

Results for 5.66E20 POT

Maximum likelihood fit.Null excluded at 99.4% with respect to the two neutrino oscillation fit.Best Fit Point (∆m2, sin2 2θ) =

(0.064 eV2, 0.96) χ

2/NDF= 16.4/12.6 P(χ2)= 20.5%

Results to be published.

E>475 MeV

Richard Van de Water, NEUTRINO 2010, June 14Slide26

A

reanalysis

of short baseline disappearance experiments seems to be

compatible with oscillations (and

requires at least one extra mass state)

Mention et al., arxiv:1101.2755Slide27

Hamann

, STH,

Raffelt

,

Wong(in preparation):What happens to cosmologicalparameters if a prior is

imposedon the neutrino mass? (this is now done in an extended

model)

1s

2s

3sSlide28

BIG

BANG NUCLEOSYNTHESISSlide29

N

n

= 3

N

n = 4Nn = 2

The helium production is very sensitive to Nn Slide30

Current helium data also suggests

extra radiation

Aver et al 2010Izotov &

Thuan 2010Slide31

WHAT IS IN STORE FOR THE FUTURE?

BETTER CMB TEMPERATURE AND POLARIZATION

MEASUREMENTS (PLANCK)LARGE SCALE STRUCTURE SURVEYS AT HIGH REDSHIFT

MEASUREMENTS OF WEAK GRAVITATIONAL LENSING

ON LARGE SCALESSlide32

Distortion of background images by foreground matter

Unlensed Lensed

WEAK LENSING – A POWERFUL PROBE FOR THE FUTURESlide33

FROM A WEAK LENSING SURVEY THE ANGULAR POWER SPECTRUM

CAN BE CONSTRUCTED, JUST LIKE IN THE CASE OF CMB

MATTER POWER SPECTRUM (NON-LINEAR)WEIGHT FUNCTION DESCRIBING LENSING

PROBABILITY

(SEE FOR INSTANCE JAIN & SELJAK ’96, ABAZAJIAN & DODELSON ’03,SIMPSON & BRIDLE ’04)Slide34

STH, TU, WONG 2006Slide35

EUCLID

ESA M-CLASS MISSION

2020-25Slide36

STH, TU & WONG 2006Slide37

THIS SOUNDS GREAT, BUT UNFORTUNATELY THE THEORETICIANS

CANNOT JUST LEAN BACK AND WAIT FOR FANTASTIC NEW DATA

TO ARRIVE…..Slide38

FUTURE SURVEYS LIKE LSST WILL PROBE THE POWER SPECTRUM

TO ~ 1-2 PERCENT PRECISION

WE SHOULD BE ABLE TO CALCULATE THE POWER SPECTRUM TO AT LEAST THE SAME PRECISION!

”LSST” ERROR BARS

-1Slide39

IN ORDER TO CALCULATE THE POWER SPECTRUM TO 1%

ON THESE SCALES, A LARGE NUMBER OF EFFECTS MUST

BE TAKEN INTO ACCOUNTBARYONIC PHYSICS – STAR FORMATION, SN FEEDBACK,…..

NEUTRINOS, EVEN WITH NORMAL HIERARCHY

NON-LINEAR GRAVITY……………………..Slide40

FULL NON-LINEAR

LINEAR THEORY

Brandbyge, STH, Haugbølle, Thomsen, arXiv:0802.3700 (JCAP)

Brandbyge & STH ’09, ’10 (JCAP), Viel, Haehnelt, Springel ’10

NON-LINEAR EVOLUTION PROVIDES AN ADDITIONAL AND VERY

CHARACTERISTIC SUPPRESSION OF FLUCTUATION POWER DUE TO

NEUTRINOS (COULD BE USED AS A SMOKING GUN SIGNATURE)Slide41

CDM

n

1 < p/T < 2

0 < p/T < 1

2 < p/T < 3

3 < p/T < 4

4 < p/T < 5

5 < p/T < 6

512

h

-1

Mpc

INDIVIDUAL HALO PROPERTIESSlide42

CONCLUSIONS

NEUTRINO PHYSICS IS PERHAPS THE PRIME EXAMPLE OF HOW

TO USE COSMOLOGY TO DO PARTICLE PHYSICSTHE BOUND ON NEUTRINO MASSES IS SIGNIFICANTLYSTRONGER THAN WHAT CAN BE OBTAINED FROM DIRECT EXPERIMENTS, ALBEIT MUCH MORE MODEL DEPENDENTCOSMOLOGICAL DATA MIGHT ACTUALLY BE POINTING TO

PHYSICS BEYOND THE STANDARD MODEL IN THE FORM OFSTERILE NEUTRINOS