Hamburg 24.10.2005

Björn Wonsak

Status and Future of -physics

Hamburg 24.10.2005

Björn Wonsak

What do I talk about?

MotivationsOscillationsStatusOpen QuestionsNear FutureNot so far FutureConclusions

Hamburg 24.10.2005

Björn Wonsak

Why are we doing ν-physics?

SM is very successfulbut it leaves a lot of questions open

(e.g. astrophysical questions, like big bang, matter-antimatter asymmetry, supernovaes, etc.)

we want to understand physics beyond the SMThere are two ways to do that:

High Energies bigger accelerators

Study rare, tiny effects more statistics, lower background

Hamburg 24.10.2005

Björn Wonsak

Why are we doing ν-physics?

Tiny effect (m/E)2~(eV/GeV)2=10–18 !

Suitable methode: InterferometryNeeds coherent source

Needs Interference (i.e., large mixing angles)

Needs long baseline

All this is given us by nature:

Neutrino Interferometry (Oscillations) is a unique tool to study physics at very high scales !!!

Lowest order effect of physics at short distances !!!

Hamburg 24.10.2005

Björn Wonsak

What are ν-oscillations?

Flavour eigenstates e,, are not the mass eigenstates 1,2,3

neutrino mixing

3

2

1

321

321

321

UUUUUUUUU eeee

This leads to oscillations between the e,, like in the Kaon system

ν must have different masses (not all are massless) Leptonflavour is not strictly conserved

Already beyond the SM !

Pontecorvo-Maki-Nakagawa-Sakata (PMNS) Matrix:

Hamburg 24.10.2005

Björn Wonsak

What are ν-oscillations?

3

2

2323

2323

cssc

Flavor eigenstates , Mass eigenstates 2,3 with m2, m3

W

vμ

μ

source createsflavor-eigenstates

v2

v3

propagation determined bymass-eigenstates

23,2

23,23,2 mpE

slightly different frequencies→ phase difference changes

vτ

W

τ

p,n hadrons

detector seesflavor-eigenstates

Hamburg 24.10.2005

Björn Wonsak

What are ν-oscillations?

Oscillation probability

2

sin2sin 22 P

E

Lm

2

2with

Pro

babili

ty t

o fi

nd

vτ

Distance x in Losz

Losz, Δm2sin2(2

θ)

experiment needs statistics

experiment needs energy resolution

Hamburg 24.10.2005

Björn Wonsak

What are ν-oscillations?

100

0

0

0

010

0

0

0

001

1212

1212

1313

1313

2323

2323 cs

sc

ces

esc

cs

sci

i

PMNSU

ji

ijjjii

ji

ijjjiivv

E

LmUUUU

E

LmUUUUP

2sin)(2

4sin)(4

2**

22**

If neutrinos are Majorana particles: 2 additional Majorana-Phases (CPV): α1, α2

Three flavour mixing:

Zero for CPconservation

3 mixing angles and 1 CP-violating phase

Hamburg 24.10.2005

Björn Wonsak

L/E is crucial !

sin2(212)sin2(213)

Example for 3 flavour Oscillation probability !

m213

m212

Hamburg 24.10.2005

Björn Wonsak

What do we know?

Atmospheric neutrinos Super-Kamiokande

Atmosphärische Beschleuniger

9.02sin

105.0

6.04.2

232

23223

eVm

Hamburg 24.10.2005

Björn Wonsak

What do we know?

Solar neutrinos

07.0

1.040.0tan

105.0

6.09.7

122

25212

eVm

KamLAND

Reaktor-Solar-

SNO

,e

Mass effects in the sun dominate !

Hamburg 24.10.2005

Björn Wonsak

What are ν-oscillations?

100

0

0

0

010

0

0

0

001

1212

1212

1313

1313

2323

2323 cs

sc

ces

esc

cs

sci

i

PMNSU

ji

ijjjii

ji

ijjjiivv

E

LmUUUU

E

LmUUUUP

2sin)(2

4sin)(4

2**

22**

If neutrinos are Majorana particles: 2 additional Majorana-Phases (CPV): α1, α2

Three flavour mixing:

4/104523

6/103012 1313

100

031

013

2

1

0

010

0

110

110

001

2

1

1313

1313

ces

esc

i

i

PMNSU

2

3,

2

11212 cs

1

12

1

1212

1212

131212

cs

cs

sc

U PMNS

Very different m2 in different sectors

Solar and atmospheric oscillations can be regarded as independent

2 flavor discription is sufficient

3 mixing angles and 1 CP-violating phase

Hamburg 24.10.2005

Björn Wonsak

What do we want to know?

Dirac or Majorana ?Absolute mass scale ?How small is θ13 ?CP-violation ?Mass hierarchy ?Verify Ocsillations ? LSND ? Sterile neutrinos ? CPT-violation ?

0: claim by Klapdor-Kleingrothaus !

direct measurement: Katrin aims for m<0,2eV

Diappearance energyspectra, apperance

can be adressed by oscillation experiments

need specialised experiments

Hamburg 24.10.2005

Björn Wonsak

What comes next?

low E neutrinos (few GeV): disappearance experiment 4 x1020 pot/year 2500 CC/year compare Det1-Det2 response vs E in 2-6 years sensitivity to m2

atm

main goal: reduce the errors on m223 and sin2223 as needed for sin2213

measurement

NUMI

MINOS

Minos

735km

Magnetized steel/scintillator calorimeter

started this year

Hamburg 24.10.2005

Björn Wonsak

NC/CC ratio measured

contains four neutrino interactions

Hamburg 24.10.2005

Björn Wonsak

Hamburg 24.10.2005

Björn Wonsak

What comes next?

τ appearance experiment(search for 13)

Emulsion Cloud Chamber (ECC)

1,8 kton mass

En ≈ 17 GeV

start end 2006

Hamburg 24.10.2005

Björn Wonsak

µ spectrometer

8 m

Target Trackers

Pb/Em. target

Extract selected brick  

Pb/Em. brick

8 cm Pb 1 mm

Basic “cell”

Emulsion

Electronic detectors select ν interacting brickµ ID, charge and p

Emulsion AnalysisVertex searchDecay searche/γ ID, kinematics

technic already used by Donut

discovery anno 2000

Hamburg 24.10.2005

Björn Wonsak

Hamburg 24.10.2005

Björn Wonsak

What comes next?

Double Chooz

100-200 m

12.7 m3

12.7 m3

Search for θ13:

Doppel-CHOOZ Reaktorneutrino experiment (France)

2 reaktors: 8.4GW Pth2 reaktors: 8.4GW Pth

100-200m

1 km

Double-Chooz sensitivity for (m2 = 2.0-2.5 10-3 eV2): sin2(213) < 0.025-0.03, 90% C.L.

first data taking beginning 2007

Hamburg 24.10.2005

Björn Wonsak

sin2(212)sin2(213)

m213

m212

Double-Chooz

Kamland

Hamburg 24.10.2005

Björn Wonsak

What comes next to next?

The first Super-Beam: off-axis T2K, from Tokai to SK

monitor (beam direction and intensity)

energy spectrum and intensity

Same spectrum as SK, BG measurement

start around 2009

Hamburg 24.10.2005

Björn Wonsak

30kt liquid Scintillator detectorNUMI beam with 6.5 x 1020 pot/yrWith a new Proton Driver, 25 x 1020 pot/yr Superbeam!Bunch time information used –physics comes back to surface

850km

16mrad off-axis

e/e

appearancestart about 2011

Hamburg 24.10.2005

Björn Wonsak

212

223

22

223121313

323121313

223

213

2

sin2sincos

sincos2sin2sincossin2sin

sin2sin2sincossin2sin

sin2sin2sin)(

CP

CP

eP

NOvA

T2K

122

134222

132 2sincossin2sin)(1 eeP

)4/(312

ELm 23121

2 / mm with

Neutrino superbeams

Neutrino superbeams

Hamburg 24.10.2005

Björn Wonsak

5 year onlyrun

for maximal atmospheric mixing

with m2≈2,5•10-3 eV2

Hamburg 24.10.2005

Björn Wonsak

What have we learned?

Smart way to reach high energy scales Already physics beyond the SMA lot of interesting open questionsFirst measurements were highly succesfull time for precision measurements

A new intertesting experiment every year fast growing knowledge