/
Current *  Neutrino Oscillation Experiments Current *  Neutrino Oscillation Experiments

Current * Neutrino Oscillation Experiments - PowerPoint Presentation

altigan
altigan . @altigan
Follow
344 views
Uploaded On 2020-07-02

Current * Neutrino Oscillation Experiments - PPT Presentation

PPAP Meeting Birmingham 15 July 2009 Elisabeth Falk University of Sussex Def current running or under construction Outline Neutrinooscillation experiments what to measure and how Acceleratorbased experiments ID: 792714

sussex falk detector experiments falk sussex experiments detector beam sin reactor minos neutrino data chooz detectors 2009 measure 2010

Share:

Link:

Embed:

Download Presentation from below link

Download The PPT/PDF document "Current * Neutrino Oscillation Experime..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.


Presentation Transcript

Slide1

Current* Neutrino Oscillation Experiments

PPAP MeetingBirmingham15 July 2009Elisabeth FalkUniversity of Sussex

Def. current: running or under construction

Slide2

OutlineNeutrino-oscillation experiments:

what to measure, and howAccelerator-based experimentsReactor experimentsConclusions and outlook15/7/09E. Falk, U. of Sussex

2

Slide3

Neutrino Mixing15/7/09

E. Falk, U. of Sussex3

Solar

n

+ KamLAND:

q

12

= (34

± 3

)

o

D

m

2

12

= 7.6

x

10

-5

eV2

Atmospheric n + MINOS, K2K: q23 = (45 ± 7)oDm232 = 2.5 x 10-3 eV2

Unknown CP-violating phase

Reactor

n

(CHOOZ):sin2 2q13 < 0.11 @ 90% CL(or q13 <~ 10o)Dm231 ~ Dm232

D

m212

n2

n1

n

3

D

m

2

32

n

e

n

t

n

m

What to measure, and how

Slide4

Accelerator-Based vs. Reactor Experiments

Reactor experiments:q13 only:Look for disappearance (ne  ne

) as a fnc of L and ENear detector to measure unoscillated flux

P

(

n

e

n

e

) independent of

d

; matter effects small

15/7/09

E. Falk, U. of Sussex

4

ND

FD

LBL accelerator experiments:

s

in2 q12, D

m232:Look for disappearance (

nm 

nm) as a fnc of L and

ENear detector to measure unoscillated spectrumq13, δCP, sign(Dm232):Look for appearance (nm  ne) in nm beam vs. L and ENear detector to measure background nes (beam + mis-id)P (nm  n

e) =

f (d, sign(Dm312

))Accelerator-based and reactor experiments complementary

MINOS, T2K, NOnADouble Chooz, Daya Bay, RENO

What to measure, and how

Slide5

Experimental Approach(

nm) disappearance measurements:Measure unoscillated nm spectrum at Near DetectorExtrapolate using MCCompare to measured spectrum at Far Detector15/7/09E. Falk, U. of Sussex

5

spectrum ratio

Monte Carlo

Unoscillated

Oscillated

Monte Carlo

n

m

spectrum

What to measure, and how

n

e

appearance measurements:

Measure

n

e

spectrum at Far Detector

Near Detector

to measure background

n

e

s (beam + mis-id)

Predict Far

Detector background using MC

~ sin

2

2

q23~ Dm2

32

Slide6

Neutrino BeamProtons strike graphite target

Magnetic horns focus secondary p/KDecay of p/K produces (mostly) muon neutrinos15/7/09E. Falk, U. of Sussex

6

Accelerator-based experiments

NuMI

NuMI

Slide7

Players: MINOS, T2K, NO

nAMINOS:NuMI (Fermilab) to Soudan mine, MN735 km baselineMagnetised sci/steel calorimetersTaken beam data since 2005Two more years of data-takingLarge UK involvementAll ana/working groups have UK co-convener(s)Made significant h/w & DAQ contributions

15/7/09

E. Falk, U. of Sussex

7

Accelerator-based experiments

T2K:

J-PARC

(Tokai) to Kamioka mine

295 km baseline, off-axis

New beam

FD: Super-K (water Cerenkov)

Start data-taking in 2010

Large UK involvement

ND280 off-axis detector

(P0D, ECAL, DAQ, ….)

NO

n

A:

NuMI (Fermilab) to Ash River, MN

810

km baseline, off axis

Upgrade beam power

“Totally active” tracking liquid sci calorimeters

Start data-taking in 2013

No UK involvement

Slide8

MINOS

Main physics results to date:nm disappearance: |Δm232

|=(2.43 ± 0.13) x 10-3

eV

2

at 68% C.L.

sin

2

(2θ

23

) > 0.90 at 90% C.L

.

Most precise result

for

|Δm

2

32

| to date

n

e appearance:1.5s excess (within realms statistical fluctuation):Normal hierarchy (dCP = 0): sin2(2θ13) < 0.29 (90% C.L.)Inverted hierarchy (dCP = 0): sin2

(2θ13) < 0.42 (90% C.L.)n

m disappearance:Study 7% nm component See 1.9s fewer events than CPT-conservingNeutral-current interaction rate:

Limit on sterile neutrinos:fs < 0.68 (90% C.L.)

15/7/09E. Falk, U. of Sussex8Accelerator-based experimentsnm disappearancene appearance

Slide9

MINOS

Future plans:Update all analyses with more than double the data setData in the can (3.2  7E20 POT)Muon antineutrino runningSwitch beam magnetic horns to focus p-Start in September this yearMake the first direct measurementReduce uncertainty on Dm232 by an order of magnitude

nm mode for 2E20 POT, or until July 2010

15/7/09

E. Falk, U. of Sussexß

9

Accelerator-based experiments

Slide10

T2KPhysics programme:

Phase I:Discovery/measurement of q13D(sin2 2q23) ~ 0.01 (1%)D|Dm232| < 1 x 10-4 eV (a few %)

(90% CL)Potential phase 2:Search for CP violationMilestones:ND suite operational by end of 2009

Beam power ramped over next few years

(2009: 30 kW; 2010: 100 kW;

2011: 300 kW; + “a few years”:

750 kW

Phase 1: total of 5E21 POT

15/7/09

E. Falk, U. of Sussex

10

Accelerator-based experiments

Slide11

NO

nASignificant injection of funds via US stimulus package revived NOnAPhysics programme:Optimised for ne appearanceAn order of magnitude more sensitive than MINOS

Improve sin2 2q23 and |

D

m

2

32

| by an order of magnitude (compared to MINOS)

Mass hierarchy (sign (

D

m

2

32

))

Long baseline: only experiment sensitive to

this

Milestones:

1 May 2009: FD groundbreakingAutumn 2011: Start of beam upgrades (400 kW  700 kW)2013: Data-taking with full FD

15/7/09E. Falk, U. of Sussex

11Accelerator-based experiments

Slide12

Dominant source of systematic error in CHOOZ:Reactor neutrino spectrum

~ Cancels out with two detectorsMeasuring q13: ne Disappearance

15/7/09

E. Falk, U. of Sussex

12

Reactor experiments

Nuclear power station

Far Detector

d = 1 - 1.8 km

n

e

n

e

Present limit from CHOOZ:

sin

2

(2

13

) < 0.15 (90% C.L.) at

D

m

231 = 2.5 x 10-3 eV2

Near Detector

d = 300 - 400 m

(

nm,t)

Slide13

The Detectors15/7/09

E. Falk, U. of Sussex13

Prompt e

+

signal

E

prompt

= E

n

– (M

n

– M

p

) + m

e

Delayed n capture on Gd

(t ~ 30 ms) with emission

of g cascade ( E ~ 8 MeV)

Outer Veto:

Plastic scintillator panelsn Target:

10 m3 liquid scintillatordoped with 0.1% Gdg Catcher:23 m3 liquid scintillatorBuffer:114 m3 mineral oil with~400 PMTs

Inner Veto:90 m3 liquid scintillatorwith 80 PMTsShielding:15 cm steel

Reactor experiments

Example: Double Chooz

Inverse Beta Decay

Slide14

Players: Double Chooz, RENO, Daya Bay15/7/09

E. Falk, U. of Sussex14Reactor experiments

Double Chooz, France

Expected sin

2

2

13

~

0.03

85 ton-GW

th

Small UK interest

(Sussex, no longer funded)

Daya Bay, China

Expected sin

2

2

13

~

0.011400 ton-GWthRENO, KoreaExpected sin22

13~

0.03250 ton-GWth

Main differences:

Reactor power/no of coresConfiguration cores vs. detectors; no. of detectorsDetector target mass

Slide15

Status and Expected Milestones*15/7/09

E. Falk, U. of Sussex15Reactor experiments

2009

2010

2011

2012

2013

2014

2009

2010

2011

2012

2013

2014

2009

2010

2011

2012

2013

2014

Double Chooz

RENO

Daya Bay

* DC schedule includes my estimated delays – not official, so don’t quote it!

RENO, DB official schedules, but at least DB will likely be delayed by a few months

ND and FD ready

for data-taking

N and F tunnels

completed

ND and FD

commissioning

sin

2

2

q

13

~ 0.03 ???

First detector complete;

start dry run

Near Hall ready for

data-taking

Far Hall ready for

data-taking;

Ling Ao Hall ready a

bit earlier

Near Hall occupancy

sin

2 2q13 ~ 0.01

FD ready for data-taking

sin

2 2q13 ~ 0.06

ND ready for

data-taking

sin

2

2

q

13

~ 0.03

ND hall + tunnel

construction begins

Slide16

Comparison of q13 Sensitivities

15/7/09E. Falk, U. of Sussex

16

M. Mezzetto, Venice, March 2009

Slide17

15/7/09

E. Falk, U. of Sussex17Comparison of q

13 Sensitivities

M. Mezzetto, Venice, March 2009

Slide18

Conclusions and OutlookPast and present experiments have pinned down

q13, Dm212, q23, Dm232MINOS recently announced 1.5s result for q13T2K and reactor experiments come on-line within

~a year from nowNext 5 years will see sensitivity to sin2 2q13 to ~0.01,

plus order of magnitude improvement on

q

23

and

D

m

2

32

Need combination of different baselines + reactor to resolve

q

13

,

δ

CP

, sign (Dm232)Would be difficult to search for δCP if sin2

2q13 < 0.0115/7/09

E. Falk, U. of Sussex18

Slide19

E. Falk, U. Sussex19

Reactor Experiment Howto: Improve on ChoozStatisticsMore powerful reactor (multi-core)Larger detection volumeLonger exposureExperimental error:

n flux and cross-section uncertaintyMulti-detectorIdentical detectors

Reduce inter-detector systematics (normalisation, calibration...)

Background

Improve detector design

Increase overburden

Improve knowledge of background by direct measurement

Larger

S

/

B

CHOOZ :

R

osc

= 1.01 ± 2.8% (stat) ± 2.7% (syst)

Reach ~1% precision

Slide20

E. Falk, U. Sussex20

Double Chooz Systematic Uncertainties

n energy,

D

t, (distance e

+

- n)

Slide21

Baselines and Reactor Power15/7/09

E. Falk, U. of Sussex21Reactor experiments

Double Chooz

RENO

Daya Bay

P = 16.1 GW

th

/6 cores

L ~ 1.4 km

P = 8.2 GW

th

/2 cores

L = 1.05 km

P = 11.6 GW

th

/4 cores

~2011:

17.4 GW

th

/6 cores

L ~ 1.8 km

Slide22

Daya Bay and Ling Ao Nuclear Power Plant

Daya Bay NPP 2.9GW

2

LingAo NPP 2.9GW

2

LingAo II NPP 2.9GW

2

Under construction (2010)

Slide23

Daya Bay Run PlanIstall first two detectors

in DB Near Hall within a year from nowTake data (engineering run) while Ling Ao and Far Halls completedAdditional detectors deployed in pairs, one in Ling Ao and one in Far Hall, as they become ready – except last pairOne detector to be moved from Near to Far HallLast pair deployed in Near + Far HallsRun for three yearsPublish

15/7/09E. Falk, U. of Sussex

23

Reactor experiments

DYB (40 t)

LA (40 t)

Far (80 t)

Slide24

Daya Bay: Redundancy

Measuring sin2213 to 0.01 need to control systematic errors very well.We believe that the relative (near/far) detector systematic error could be lowered to 0.38%, with near/far cancellation and improved detector design.Side-by-side calibration: Event rates and spectra in two detectors at the same near site can be compared  How IDENTICAL our detectors are?

Detector swapping: Daya Bay antineutrino detectors are designed to be MOVABLE. All detectors are assembled and filled with liquids at the same place. Detectors at the near sites and the far site can be swapped, although not necessary to reach our designed sensitivity, to cross check the sensitivity and further reduce the systematic errors.

DYB (40 t)

LA (40 t)

Far (80 t)

Slide25

15/7/09E. Falk, U. of Sussex

25Reactor experiments

2010

2011

2014

2013

2012

2015

sin

2

2

q

13

limit

Far Detector

only

Far+Near Detectors

s

sys

= 2.6%

s

sys

= 0.6%

Comparison of

q

13 SensitivitiesDaya BayDouble Chooz

Slide26

Comparison of

q13 Sensitivities15/7/09E. Falk, U. of Sussex

26

M. Mezzetto, Venice March 2009

Assumptions:

DC to start end

of 2009; ND 1.5 yrs later

More likely 2

nd

quarter of 2010 (my estimate)

DB

to start mid 2011

From C. White: Schedule slipping by a few months

T2K: 0.1 MW in 2010;

0.45

MW in 2011;

0.75 MW thereafter

From D. Wark:

0.1 MW in 2010;

0.3 MW in 2011; ramp to 0.75 MW over a few years

MINOS, OPERA:

sensitivity as per proposal, scaled by POT

Slide27

Overview

Long baseline Fermilab  735 km  SoudanNear detector at FermilabMeasure beam composition, energy spectrumFar detector in MinnesotaSearch for and study oscillationsTest the nm

 nx oscillation hypothesisMeasure precisely |

D

m

2

32

| and

sin

2

(2

q

23

)

Search for sub-dominant

n

m

 ne oscillationsSensitive to q13Other MINOS physics:Search for sterile neutrinos, CPT/Lorentz violation

Compare nm, nm oscillationsStudies of cosmic rays and atmospheric neutrinos

Neutrino interaction studies in the Near Detector15/7/09

27E. Falk, U. of SussexMINOS

Slide28

Muon-Neutrino Disappearance Analysis

Strong energy-dependent spectrum distortionSpectrum fit with two-flavour oscillation hypothesisFit constrained to physical region + includes three largest systematicsResults:|Δm2

32|=(2.43 ± 0.13) x 10

-3

eV

2

at 68% C.L.

sin

2

(2θ

23

) > 0.90

at 90% C.L.

15/7/09

E. Falk, U. of Sussex

28

PRL

101

131802 (2008)Most precise measurement of |m232

| to date MINOS

Slide29

Antimuon-Neutrino Disappearance Analysis

Measure |Δm232|, sin

2(2θ

23

)

Test CPT

FNAL Wine & Cheese three weeks ago

n

m

CC events are 7% of beam

Mis-ID muon and NC backgrounds relatively larger

As CC analysis, but with extra cuts

Track-length likelihood, charge-sign significance

15/7/09

E. Falk, U. of Sussex

29

MINOS

Slide30

16th-22nd July 2009

30Justin EvansThe FutureAll these analyses have used 3x10

20 of the 7x1020 protons-on-target that have been recordedAs of this June’s summer shutdown

Over the next year, the analyses will be updated with the increased dataset

Using the blind analysis policy on the new data

Graphs below show the

θ

13

sensitivity for 7x10

20

PoT

If the excess persists

If the excess goes away

Slide31

Electron-Neutrino Appearance Analysis

Sub-dominant neutrino oscillationsP(νμ→

νe) ≈ sin

2

θ

23

sin

2

2

θ

13

sin

2

(1.27

Δ

m

2

31

L/E)

Also CPv and matter effects: not shown here but included in fit

ANN algorithm to select ne eventsBackground measured in NDNC events, high-y nm CC, beam ne, oscillated nt at FDData-driven technique: compare horn on/off dataPredict FD background from measured ND background + MC 15/7/09E. Falk, U. of Sussex

31

CC Event

NC Event

eCC EventMINOS

Slide32

Electron-Neutrino Appearance Analysis

Far Detector spectrum obtained after blind analysisExpected background: 27 ± 5(stat) ±

2(syst)Contours from Feldman-Cousins methodFit to number of eventsObserved events:

37

Results:

Normal hierarchy (

d

CP

= 0):

sin

2

(2θ

13

) < 0.29 (90% C.L.)

Inverted hierarchy (

d

CP

= 0): sin2(2θ

13) < 0.42 (90% C.L.)1.5s

excessWell within realms of statistical fluctuation15/7/09E. Falk, U. of Sussex32MINOS

Slide33

Neutral Current Analysis

General NC analysis overview:All active neutrino flavours participate in NC interactionMixing to a sterile ν will cause a deficit of NC events in Far DetectorAssume one sterile neutrino and that mixing between νμ, νs

and ντ occurs at a single Δm2

Survival and sterile oscillation probabilities become:

μ,s

= mixing fractions)

15/7/09

E. Falk, U. of Sussex

33

Simultaneous fit to CC and NC energy spectra yields the fraction of ν

μ

that oscillate to

ν

s

:

MINOS

Slide34

Future PlansUpdate all analyses with more than double the data set

Muon antineutrino possibilitiesSwitch beam magnetic horns to focus p-MINOS can make the first direct measurementReduce uncertainty on Dm232 by an order of magnitude15/7/09

E. Falk, U. of Sussex

34

MINOS

Slide35

Main Measurements: sin2q13

Use CCQE: ne + n  e- + pMain backgrounds:Beam n

e contaminationNC p0 events

15/7/09

E. Falk, U. of Sussex

35

T2K

Simulated SK spectrum

Slide36

Main Measurements: sin2q23,

Dm232Use CC quasi-elastic events:nm + n

 m- + p

Background from non-CCQE interactions

15/7/09

E. Falk, U. of Sussex

36

T2K

D

m

32

2

sin

2

2

q

23

n

m

disappearance

Precision

prospect:

D

(sin

22q23) ~ 0.01 (1%)D (Dm232) < 1 x 10-4 eV2 (a few %) at 90% C.L.@ Dm2 ~ 2.5 x 10

-3

eV2

Slide37

J-PARC Accelerator Complex

15/7/09

E. Falk, U. of Sussex

37

T2K

Commissioned,

in use for material & life science

Protons to 30 GeV on 23/12/08

Commissioning is on time

Commissioned,

in use for material & life science

n

beam-line components

Commissioning in progress

Neutrino Beam Line

Slide38

Near Detectors at 280 mOn- and off-axis detectors 280 m downstream of target

Understand the neutrino beam before oscillations occurT2K timelineApr 09: Beam-line commissioning 10 daysSummer-autumn 09: Install INGRID & ND280Oct 09: Restart beam commissioningDec 09-June 10: Physics runAim to improve CHOOZ limit15/7/09

E. Falk, U. of Sussex

38

On-axis: INGRID

Scintillator/iron

modules

ND 280: Off-axis detectors

inside UA1 magnet

T2K

Slide39

Beam Power Projections15/7/09

E. Falk, U. of Sussex39

April 1, 2009

T2K

Slide40

Discovery Potential15/7/09

E. Falk, U. of Sussex40

T2K