061128Seminar at Kanazawa U.1 Future Neutrino Facilities “ Plan B ” of the World High Energy...

061128 Seminar at Kanazawa U. 1

Future Neutrino Facilities “Plan B” of the World High Energy Community

Yorikiyo NagashimaOsaka University

November 28, 2006Kanazawa University


International Scoping Studyof a Neutrino Factory and

super-beam facility

Joint Effort by ECFA/BENE NuFact-J US Muon Collider and Neutrino Factory Collaboration UK Neutrino Factory collaboration Hosted by CCLRC/RAL

Proposed at NuFact05. Final report to NuFact06 ( August 24, 2006)

(http://www.hep.ph.ic.ac.uk/iss/)


What to do?

Investigate a best strategy for the long future of the neutrino physics considering the ongoing and near future plans of three regions.

Chairman : P.Dornan (ICL) Conveners:

Physics working group : Y. Nagashima (Osaka) Detector working group: A.Blondel (CERN) Accelerator working group: M.Zisman (LBL)


Where do we go from here ?Two directions beyond SM, toward

Unification

◆ EW symmetry breaking, ◆ HIGGS, GUT, SUSY, ED 　　 LHC, ILC ◆ Clear theoretical guide exists: Top down approach◆ Discovery !

◆ Flavor Problem◆ Origin of generations, Mass Hierarchy 　 Super B, Factory◆ No clear theory exists. Only experimental observations:

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　 Bottom Up Ap

proach◆ Precision and surprise !


Many of these questions usually reside in GUT scale and beyond,


A given GUT model usually has generic predictions for low energy observables.Studying ’s gives considerable insight into phenomena which otherwise would be inaccessible.Colliders can not probe this kind of physics, since any effects in scattering amplitudes are suppressed by MGUT, ~O(10-10) at LHC !


Key measurements The most sensitive low energy observables are

Majorana mass – 0

Absolute m – Katrin, Cosmology

Oscillation measurements can address following questions.How large is ? Leptonic CP violation ? 　 mass hierarchy ? Is maximal ?Unitarity test and/or more than 3 ’s? Test of Q-L complementarity: ex.Test of Sum rules: ex.

Model prediction


The neutrino mixing matrix: 3 angles and a Dirac phase 2 Majorana phases

e

c12c13 s12c13 s13e i

s12c23 c12s13s23ei c12c23 s12s13s23e

i c13s23

s12s23 c12s13c23ei c12s23 s12s13c23e

i c13c23

1

2

3

Majorana phases do not contribute to oscillations

実験的には ?


Unknown or poorly known 13 , CP phase , sign of m2

13

m213= 2 x10-3eV2

m212= 8 x10-5 eV2

From now on, assume standard 3 flavor oscillation.Use above 3 indicators forOptimization of future neutrino facilities.


Neutrino Oscillation Appearance Probability

大気 (13)項 .

太陽項 .

CP 項 .

sin2213<0.1 ~ 0.04

061128 Seminar at Kanazawa U. 14Yellow; Numi, 45mrad

E of most SB and BB peaks at ~1GeV

Neutrino Factory


LBL expts. operate at atmospheric distance

optimum

E=1GeV

Note: The functions scale as L/E

Earth diameter


To resolve mass hierarchy, a long baseline 　 (>1000km) is needed

Magic Baseline


3 types of accelerator neutrino facilities

Super BeamConventional: use ビビビ Mega watt class proton acceleratorContamination of e in beam

Beta BeamProduce beta active isotope A* Aee ： e ビーム

And accelerate (use SPS or LHC)Q-value low collimated beam, small BKG

Neutrino FactoryUse from decay, cool, accelerate, store and let decay : e ビームClean, intense, high energy (10-30GeV), all channels availableConsidered as an ultimate neutrino facilityNeeds R&D, Cost?

Ongoing experiments are all of SB type


Accelerator ExperimentsPhase Japan U S Europe

1. Now K2K (done) (250 km)

MiniBooNEMINOS (735 km)

OPERA, ICARUS (730 km)

2. Next 5 yrs

T2K (2009~)

(295 km)NOA (2013~)

(810 km)3. Next 10 yrs ?

T2KII (4MW)T2HK (SKHK)Or T2KK (~1200km)

NOA IIw/PD and 2nd OADetector

WBB with very long baseline ( >2000km)

MEMPHYS(130km)(SPL+ Beam, =150)

4. After that

Factory ?(E=20-50 GeV, 4000+7500km)

Beam ? (=350,730km)

Confirm atm. Osci.

Find 13

Measure CP, solve MH

Ultimate facility


Super Beam (< 1MW 4MW) T2K, NOvA, SPLFind non-zero 13 down to sin2213 ~ 10-2

Expect to measure m213:

23% 10% MINOS 2% T2K, NOvA

Super Beam Phase II (Detector Upgrade) T2HK, NOvAIIsin2213 ~10-3 mass-hierarchy up to sin2213 ~ 10-2 for all values of NOvA II, T2KKSearch for CP violationm13

2 　　　 1%

Note: Reactor is very competitive in search of 13

061128 Seminar at Kanazawa U. 20Adapted from Lindner et al.,Hep-ph/0403068, 0503101

~2013

Future


Correlation and Degeneracy P(e)=Asin2213+sin213(Bcos ±Csin )+D　 Measurement of 　　　　　　　　　　　　　　 at fixed E/L gives a line in 13-CP plane.　 Measurement of both gives a two-fold (13-CP or intrinsic) degeneracy

(-) (-)

CP CP

DegeneracyCorrelation


Total of8-fold degeneracy (intrinsic) ambiguity Mass hierarchy two-fold (sign) degeneracy: |m2

31|=|-m231|

(octant)degeneracy: sin2223= sin22()23

Sign degeneracy


(a) 2 different L/E or a wide band beam

(b) Same L/E 2 different channels

Solving the degeneracy

Synergy of independent experiments

CP CP


Degeneracy free, clean experimentShort baseline reactor experiments:

2nd term small for sin2213 >> 10-3 !

(see e.g. Akhmedov et al., hep-ph/0402175)

No CP, No mass hierarch

y!

Note: 31=m231L/4

DChooz


Reactor data are more effective than anti-neutrinos

Note: Reactor II : sin2213=0.01

M.Lindner; hep-ph/0503101


NOvA alone suffers from sign degeneracy.Adding reactor data solves the problem.


Near Future : Next 5 yrs. (Super Beam I)

T2K (Japan) 295km

C2GT (CNGS beam) 730km

NOA(NUMI beam) 810km

They all look for ~ e oscillations


Detectors for SB and BB are similar.Type 1: Water cherenkov counter a la SK (=50 kt) Upgrade x10 volume : ~Megaton Hyper Kamiokande, UNO, MEMPHYS

E< 1GeVQuasi Elastic eventsLarge volume


Detector for SB, Type 2, 　 TASD: Totally Active Scintillator Detctor a la NOvA

E ~1-5GeVModerate Volume

Proposed NOvA Detector•30 ktons of liquid scintilltor•15.7m x 15.7m x 132m•1984 layers•635,136 cells, each 3.8x6.0x1570 cm3 •Readout by WLS+1 APD •~20 p.e. expected

Readout


T2K can probe 　 sin2213~0.01 　　 .

And also has some sensitivity to CP


5 yr only

2.5 yr each

and run

2.5 yr each

and run

2.5 yr each and _

NOvA compared withT2K


95% CL Resolution of the Mass Ordering

T2K

NOvA’s strength is in mass hierarchy.


Near Future / ”next 10 yrs” P.Huber et al., hep-ph/0403068

NOAII

m2=2.0x10-3eV2

Super Beam: Phase IIＸ 1 ０ improvement 　 over ongoing experi

ments

T2HK

II


NOvA’s effort to compete with T2HK

Gary Feldman, WIN’05


+

+

++

+

NOA

95% CL Resolution of the Mass Hierarchy

Possible Reach in 2010-2020

Here, NOvA’s long baseline is an advantage.

2nd detector


T2KKT2HK’s solution to compete with NOvA II

Split T2HK detector into two and place one in Korea

Long baseline helps to resolve degeneracy at Kamioka.T2KK reach

comparable or better than

NOvA and T2HK combined

T.Kajita, K.Nakamura

P.Oddone


sin2213=0.05

By taking ½ to Korea, the ability to solve degeneracies enhanced .


T2KK: enhanced abilities Note; the difference in systematics

(3m312=0.0025 eV2

PRELIMINARY

(Barger, Huber, Marfatia, Winter, in preparation)(Barger, Huber, Marfatia, Winter, in preparation)


22

33T2K-II(Kamioka)

Kamioka+Korea

Expected sensitivityExpected sensitivity

22

T2K II (Kamioka)

33

Kamioka + Korea

Sensitivity to CP(sin≠0) Sensitivity to mass hierarchy

Neutrino + anti-neutrino runs = 8 years

hep-ph/0504026

3 T2HK+ NovaIntermediate

3 T2HK+ Nova

Conclusion: T2K~NOvA, T2HK~NOvA II except mass hierarchyT2KK~NOvA II in all aspects


US: Further effort :NOvA comparable with T2K in 13, CP

NOvA II outperforms T2HK in mass hierarchy, but T2KK can compete with NOvA II.

Their solution? Wide Band Beam w/very long baseline .

BNL FNAL

UNO or Liq. Ar. at far site


If WBB and the UNO water cherenkov detector can perform as claimed

it is as good as any other Super Beam experiments.However,

No direct E information: E has to be reconstructed

Use Quasi Elastic EventsRejection of NC BKG is crucial.Liq. Ar. is a solution, but a large Liq. Ar. Det. ?

Under investigation


T2KK is good at sin2213 and CPV discoveryWBB is better at mass hierarchy.

Comparison of SB performances I


Why is T2KK good at 13 and CPV ?Large mass counts !

Comparison of SB performances II


The MEMPHYS Project: SPL (Super Proton Linac) and Beta-Beam : From CERN to FREJUS

Fréjus

CERN

130km130km

4800mwe

SPL @ CERN: On axis beam2.2GeV, 50Hz, 2.3x1014p/pulse 4MWNeutrino beam energy: ~0.3 GeV

Future possibility: CERN to Gran Sasso in Italy (730km)

In the meantime, Europeans are thinking ahead. .

3x145 ktons Water Cherenkov


CERN Super-beam: θ13 and CP discovery reach. .

T2HK (slightly) out-performs SPLT2HK closer to being systematically limited (effect of going from 2% systematic errors to 5%) .


So look into possibility of adding a beam.• Produce beta active isotopes• Store 18Ne, 6He, accelerate and let them decay

to produce pure e and e beams•He- 2.9×1018 decays per year, max. =150 @SPS•Ne- 1.1×1018 decays per year, max. =250 @SPS

• Two beta-beam options considered.•BB1: =100, L=130km (CERN to Frejus)•BB2: =350, L=730km (CERN to Gran Sasso)

•Note: Tevatron and LHC can give ~350 , <~800, respectively.


Advantage of Beam1.Flux and E-spectrum well-kown 1%2.Pure e beam, LE in ion-CM

• Strong collimation good at LBL• Near/Far spectrum very similar

3. Low BKG4. Adjustable E Experiments @diff. E5. Synergy w/SPL　　 Can run both at SB mode (e) and

BB mode (e ) Useful to resolve degeneracy Suitable for T, CPT exp.

061128 Seminar at Kanazawa U. 50J-E. Campagne et al hep-ph/0603172

SPL+BB1 synergy

SPL alone cannot outperform T2HK, but the combination of SPL and BB1 does.


Neutrino Factory

Provides clean intense e channel (Golden)

and e channel (Silver)

and e channel (Platinum) And disappearance channels

and e e

NF (golden)+SB combined solves degeneracies

down to sin2213 ~ 10-5

Considered as the ultimate neutrino facilityThe question is cost consideration (1500M$+400M$*E/20 in Study II)

Long Future/ “next 20 years ? ”


Neutrino Factory:Concept:Produce intense ’s.Phase rotate and cool.Accelerate and store.Up to 1021 decay ’s /yr.

NF design as of 2006


NF: baseline detector as of 2006

Baseline: 50 kt Iron detector with E=50GeV 1021 decays/yr; exposure ‘5 plus 5’ years


ISS Study 1 : Optimization of Golden channel (e )Baseline: 50 kt Iron detector with E=50GeV

1021 decays/yr; exposure ‘5 plus 5’ years

Improved detector: “Golden*”

‘Improved’:

– Threshold

– Resolution

‘Baseline’:

– Threshold

– Resolution

Similar to NOvA detector


NF: with improved (Golden*) detector

One detectorGolden*

Better Threshold

Better detector threshold makes L=2000-4000 km very efficient 13-baseline for exclusion limit

Huber, Lindner, Rolinec, Winter hep-ph/0606119


ISS study 2 : additional channels in NF:

Emulsion cloud chamber: “Silver”OPERA-like performance ; 5 kTon

Emulsion cloud chamber : “Silver*”10 kT + 5 times efficiency

Liquid argon detector: “Platinum”

15 kTon; Eres ~ 0.15% × E ; charge ID to 7.5 GeV0.2 signal efficiency, 0.01 charge confusion

Golden* with electron CID : “Platinum*”

50 kt charge ID up to 50 GeV

Note: Siver* and Platinum* very optimistic spec.


supermodule

8 m

Target Trackers

Pb/Em. target

ECC emulsion analysis:

Vertex, decay kink e/ ID, multiple scattering, kinematics

Extract selected brick

Pb/Em. brick

8 cmPb 1 mm

Basic “cell”

Emulsion

trigger and locate the neutrino interactions muon identification and momentum/charge measurement

Electronic detectors:

Brick finding, muon ID, charge and p

Link to muon ID,Candidate event

Spectrometer

p/p < 20%

Silver Channel


Platinum channel:

Platinum*

Platinum

Useful to resolve degeneracy However, Liq. Ar. Detector suffer from CID upper limit. Currently Charge ID < 7.5 GeV

Improves performance at large sin2213 (0.1-0.01)CID upper limit OK, here

High efficiency compared to scintillators

x 2-3


At magic baseline (~7500km)

Resolves degeneracy problem.But, no sensitivity to CP or sign(m2

13)

Addition of Golden(*) at magic baseline

Combination of 1 detctor at L=7500* solves degeneracy and another at 3000km measure CP and sign(m2

13) looks best **.

Note: * Indian INO is located at MB from CERN. http://www.imsc.res.in/~ino/

** do not consider other useful channels.

http://www.imsc.res.in/~ino/

http://www.imsc.res.in/~ino/


NF: alternative way to resolve degeneracy

Addition of either silver or platinum channel solves the degeneracy problem.

However, detector feasibility is uncertain.Note 1 : Improved detector (Golden*) alone performs just as well.Note 2 : The optimal solution is to add 2nd detector at MB.


ISS Study III : NF Optimization Potential . .

(1) Golden50 kT, MID, L = 4000 kmEμ = 50 GeV(2)=(1)+(Golden)MB(3)=(2), but Golden ->Golden* and E=20GeV(4)=(3)+Platinum*

Current proposalGolden detector at 4000km and at MBE : 20-50GeVUpgrade later to Golden*

5% error2% error

P.Huber et al., hep ph/0606119


ISS study on NF: SummaryPast NF optimized for cleanest wrong sign muon HE

sit at tails of 1st maximum suffer from degeneracyImproved detector sensitive to 1st maximum help to solve degeneracy

Established Doable E range 20-50GeV (used to be 50 GeV or above) NF competitive with SB at large sin2213=0.1-0.01

Performance of additional channelsDegeneracy can be solved by addition of MB, or improved detector (golden*), or addition of silver* or platinum*.Silver or Platinum are not enough, however

Silver* and Platinum* need extensive R&DCurrent choice of detector configuration

Golden at 4000km and MB (7500km) then upgrade to Golden*


Performance comparison of various facilities.

(On equal footings)Experimental conditions.

The bands in figures indicateSystematics: SPL and T2HK from 5% to 2%

WBB as proposalBeta beam: from BB1: =100, 500kt water C (130km)

to BB2: =350, 500kt water C (730km)Neutrino Factory:

from Golden (4000km), Eμ = 50 GeV to Golden* (4000 km)+ Golden* (7500 km), Eμ = 20 GeV


θ13 Sensitivity Mass

hierarchy .

Preliminary

Preliminary

NF can outperform SB and BB for sin2213 < 0.001

ISS Study IV : Comparison


Comparison: CP violation .

Preliminary

BB2 does best at sin22 13 > 10-

2.5

However, SB may come earlier.For sin22 13 < 10-3, NF is unique.


Which option for large 13 /or for small 13?

(from Huber et al, hep-ph/0601266)Superbeam? (loweset possible effort).

May suffer from systematics: more R&D-beams + SPL are more sensitive for sin2 213 > 0.01.

below this value NF is more sensitive.Decision point for small sin2213 (= 0.01) for NF ?

Depends on what optimized for : MH or CPV. Take two ?

Decision point ?


Evaluation of the facilities: Summary

SB can be sensitive down to sin2213~10-3

T2HK is competitive with any other SB facilities (NOvA, SPL, or WBB ) except on mass hierarchy. T2KK solves this problem and improves CP sensitivity considerably .BB1 is marginally better than SB, but has no sensitivity on mass hierarchy.BB2 extends 13 reach considerably

and is the best performer in CP at large 13(≧10-2.5)BB can be competitive with SB/NF, if it can be built easily on existing facility like SPS.NF has no match for 13 < 10-3, can reach 10-5 and competes favorably at large 13 .Decision point for NF, when sin2213 < 0.01 ?But, what is the most likely value of sin2213 ?

If sin213<<0.1, some symmetry is required. Many models that predict large 12 and 13, tend to have a sizeable value of sin2213.


Identifying the correct theory:Precise knowledge of neutrino mixing parameters can discriminate:


What to do for future ?IDS (International Design Study ) : starting soonTarget: CDR by 2012 : • proposal as a post LHC or ILC parallel project ?

For Japan, the path seems already fixed.Plan B is running already ahead of Plan A !Neutrino projects and possibly Super B.

So, cross fingers for early discovery of sin2213

and go to T2HK or T2KK to verify CP violation. Challenge: reduce systematics < 2% ??


終

061128Seminar at Kanazawa U.1 Future Neutrino Facilities “ Plan B ” of the World High Energy...

Documents

Transcript of 061128Seminar at Kanazawa U.1 Future Neutrino Facilities “ Plan B ” of the World High Energy...