Summary of Nufact-03 Alain Blondel NuFact 03 5th International Workshop on Neutrino Factories &...

Summary of Nufact-03 Alain Blondel

NuFact 03 5th International Workshop on Neutrino Factories & Superbeams

Columbia University, New York 5-11 June 2003

Highlights and personnal impressions

http://www.cap.bnl.gov/nufact03/


first results from miniboonefirst results from MUSCAT!theta13 prospectives (reactor proposals!) the issue of degeneraciesbeta beam getting close in performance to neutrino factory?!Nufact: death of bow-tie

machine part: MICE strongly recommended – in approval pathstatus of target status of RF cavity studiesstatus of accelerator design FFAG!!!! Cooling ring!!!!to cool or not to cool?cost saving hopes

WORLD STUDY III

synergies: emphasis on low energy muon and high intensity physics

personnal reflexions:Europe’s strengthstwo avenues for Europe: when should we chose?

NUFACT03 Highlights


peak

Miniboone


MUSCATan important experiment to re-measure multiple scattering for low Z materials (discrepancies between theories and theory vs expt)engineering run 2000… several teething problems2. new measurements in spring 2003 at Triumf with many improvements (sci-Fi tracker!)

Short LH2 empty

Short LH2 full

Long LH2 full

Results…….Results…….

2003 Physics run all went very well–46M events taken; LH2 as well as solid targets–First look at data: very good; Analysis just starting

First results: ENG meeting 9th July (?)


J Louis

approved (MINOS, OPERA, ICARUS) programmeon approval path (J-PARC SK) will lead to improvement vs CHOOZ by factor 2-3 (MINOS, ICARUS+OPERA with tau optimized beam) by factor 5 specially optimized L.E beam for ICARUSby factor 20 J-PARC SK

what else?


Superbeam possibilities

1. J-PARC SK (2008 onwards) J-PARC HK (1 Mton) will not begin excavation before results from J-PARC SK are obtained 2011? also hopes to increase intensity from 0.7 MW to 4 MW.

2. Off-axis NUMI beam exists with required flexibility detector design in progress – will lead to a LOI in the fall near detector. (how can this be in time to be competitive???)

2’. CNGT: need beam (not CNGS) and detector. Detector viability? (single wall is ‘technologically risky’)

+ interesting: what is the physics of an off axis at the second osc. max? - no near detector NB similar idea had been put forward by Susuki in 2000 in an immersed super-tanker. both 2 and 2’ are dedicated detectors that can do nothing else as such. (CNGT could be re-deployed as km3 detector)

3. BNL homestake mine 4. SPL + beta beam Frejus a very serious contender iff beta beam can perform as advertised. (almost a neutrino factory!) ecavation could start in 2008 (better get our act together!) the most consistent scheme for a CERN based effort! support SPL + propose the Fréjus International Laboratory


NuMI Off-axis Detector

Low Z imaging calorimeter: Glass RPC or Drift tubes or Liquid or solid scintillator

Electron ID efficiency ~ 40% while keeping NC background below intrinsic e levelWell known and understood detector technologiesPrimarily the engineering challenge of (cheaply) constructing a very massive detector

How massive??

50 kton detector, 5 years run => 10% measurement if sin2213 at the CHOOZ limit, or 3 evidence if sin2213 factor 10 below the CHOOZ limit (normal hierarchy, =0), or Factor 20 improvement of the limit

Para


NuMI Off-axis50 kton, 85% eff, 5

years, 4x1020 pot/y

JHF to SKPhase I, 5 years

all After cuts all After cuts

CC (no osc) 28348 6.8 10714 1.8

NC 8650 19.4 4080 9.3

Beam e 604 31.2 292 11

Signal (m223=2.8x 10-3,

NuMI/JHF)867.3 307.9 302 123

FOM (S/sqrt(B)) 40.7 26.2

Para


Determination of mass hierarchy: complementarity of JHF and NuMI

Combination of different baselines: NuMI + JHF extends the range of hierarchy discrimination to much lower mixing angles

Minakata,Nunokawa, Parke

Para


BNL Homestake Super Neutrino Beam

2540 km

Homestake BNL

28 GeV protons, 1 MW beam power500 kT Water Cherenkov detector5e7 sec of running, Conventional Horn based beam

Diwan


Advantages of a Very Long Baseline

DISAPPEARANCE

0

50

100

150

200

250

0 1 2 3 4 5 6 7 8 9 10

Reconstructed Energy (GeV)

BNL-HS 2540 km

sin2223 = 1.0

m2 32 = 2.5e-3 eV2

1 MW, 0.5 MT, 5e7 sec

No oscillations: 13290 evts

With oscillations: 6538 evts

Background: 1211 evts

neutrino oscillations result from

the factor sin2(m322 L / 4E)

modulating the flux for each

flavor (here disappearance)

the oscillation period is directly proportional to distance and inversely proportional to energy

with a very long baseline actual oscillations are seen in the data as a function of energy

the multiple-node structure of the very long baseline allows the

m322 to be precisely measured

by a wavelength rather than an amplitude (reducing systematic errors)

Diwan


e Appearance Measurements

a direct measurement of the

appearance of e is important;

the VLB method competes well with any proposed super beam concept

for values > 0.01, a measurement

of sin2213 can be made (the

current experimental limit is 0.12)

for most of the possible range of

sin2213, a good measurement of

13 and the CP-violation parameter

CP can be made by the VLB

experimental method

Diwan


e Appearance Measurements (Cont.)

even if sin2213 = 0, the current

best-fit value of m212 = 7.3x10-5

induces a e appearance signal

the size of the e appearance signal

above background depends on the

value of m212; the figure left

indicates the range of possible

measured values for the e

yields above background for various assumptions of the final value of

m212

Diwan


very long baseline proposal (BNL homestake mine)

-- interest: CP violation and sign m213 from 1st to second peak comparison

-- energy dependence helps extracting the physics

criticisms: 1. very large mass required to reach decent sensitivity (1/L2 dependence hurts)

2. possibility of detecting e signal at > 1-2 GeV seriously criticized


BETA BEAMS

Concept proposed by Piero Zucchelli

•Produce radioactive ions (ISOL technique)•Accelerate them in the CERN accelerator complex up to of order 100• Store ions in a storage ring with long straight sections aimed at a far detector

Advantages

•strongly focussed neutrino beam due to small Q value of beta decays (quality factor /Q)• very pure flavour composition ( contamination ~ 10 -4 )•perfectly known energy spectrum

Baseline scenario studied at CERN (Mats Lindroos and collaborators)

Recent progress presented at a special workshop at MoriondPossible synergy between beta beams and EURISOL

Updated study of expected performances (Mauro Mezzetto)


A new idea for the ion source: using a pulsed ECR source

Idea proposed by Pascal Sortais at Moriond workshop

Based on experimental work done at Grenoble with Phoenix

=> High density/high frequency plasmas allow to produce efficientlyshort bunches (20 s instead of 20 ms) of ions with a high repetitionrate (16 Hz) by pulsing the RF and the HV

Advantages:Ions are already very well bunched and (hopefully) totally stripped

This simplifies considerately the design downstream:

• Possibility to use a LINAC rather than a cyclotron or a FFAG•Multiple turn injection in the storage ring becomes possible (40 turns)


New RFQ

LINAC 3

PSB

Simplification of the injection system

P. Sortais, Moriond workshop


sin2 130.0003 0.001 0.003


and measurements using superbeam and betabeam

SPL:

2 years in + 8 years in anti

BETABEAM:

10 years of 6He AND 18Ne

(Mauro Mezzetto)


UPDATED CP sensitivity :

domain of 99% CL effect for maximal CP violation


Future Measurement of sinFuture Measurement of sin22221313 at at

Nuclear ReactorsNuclear Reactors

Jonathan LinkJonathan Link

Columbia UniversityColumbia University

June 6, 2003June 6, 2003

′03


Krasnoyarsk, Russia (hep-ex/0211070)Krasnoyarsk, Russia (hep-ex/0211070)

115m1000m

Completely underground facility was used Completely underground facility was used by the Soviets forby the Soviets for weapons weapons production.production.

• One ~2 GW reactor

• Two 50 ton detectors

• Near detector at 115 meters

• Far detector at 1000 meters

• About 60 days of reactor off running per year.

• ~100 GW·tons (4 years → ~0.02)


near near

far

Kashiwazaki, Japan (hep-ph/0211111)Kashiwazaki, Japan (hep-ph/0211111)• 7 Reactors, 24 GWthermal (most powerful site in the world)

• Three ~8 ton detectors

• Two near detectors at baselines of 300 to 350 meters

• One far detector at ~1300 meters

• ~190 GW·tons

See O. Yasuda in WG1 today at 16:00


US Reactor Sites State Cores Avg GW th Max GWthPalo Verde AZ 3 10570 11552South Texas Project TX 2 6864 7600Braidwood IL 2 6491 7172Vogtle GA 2 6456 7130Byron IL 2 6442 7172Browns Ferry AL 2 6377 6916Limerick PA 2 6365 6916Peach Bottom PA 2 6290 6916Sequoyah TN 2 6209 6822Oconee SC 3 6204 7704Susquehanna PA 2 6161 6978Catawba SC 2 6116 6822San Onofre CA 2 6061 6876Diablo Canyon CA 2 6043 6749Comanche Peak TX 2 5986 6916McGuire NC 2 5880 6822North Anna VA 2 5129 5786St. Lucie FL 2 4925 5400Edwin Hatch GA 2 4901 5526Arkansas Nuclear AR 2 4844 5383Calvert Cliffs MD 2 4813 5400Joseph Farley AL 2 4801 5550Dresden IL 2 4779 5914Brunswick NC 2 4701 5116Surry VA 2 4664 5092Nine Mile Point NY 2 4500 5317Quad Cities IL 2 4481 5914Indian Point NY 2 4467 6096La Salle IL 2 4323 6978Salem DE 2 4281 6918

Possible U.S. SitesPossible U.S. SitesTop 30 U.S. Sites by Power

Performance• Most U.S. sites have one or two reactors.

• One and two reactor sites are conceptually easier: only one baseline. (The experiment can be done at multi-reactor sites.)

• U.S. two reactor sites are among the best in the world in power performance.

~350 GW·tons (with a 50 ton detector)

• Many U.S. sites have other favorable qualities such as potential for shielding.

The challenge will be getting reactor operators to agree to work with us!

US Reactor Sites State Cores Avg GW th Max GWthPalo Verde AZ 3 10570 11552South Texas Project TX 2 6864 7600Braidwood IL 2 6491 7172Vogtle GA 2 6456 7130Byron IL 2 6442 7172Browns Ferry AL 2 6377 6916Limerick PA 2 6365 6916Peach Bottom PA 2 6290 6916Sequoyah TN 2 6209 6822Oconee SC 3 6204 7704Susquehanna PA 2 6161 6978Catawba SC 2 6116 6822San Onofre CA 2 6061 6876Diablo Canyon CA 2 6043 6749Comanche Peak TX 2 5986 6916McGuire NC 2 5880 6822North Anna VA 2 5129 5786St. Lucie FL 2 4925 5400Edwin Hatch GA 2 4901 5526Arkansas Nuclear AR 2 4844 5383Calvert Cliffs MD 2 4813 5400Joseph Farley AL 2 4801 5550Dresden IL 2 4779 5914Brunswick NC 2 4701 5116Surry VA 2 4664 5092Nine Mile Point NY 2 4500 5317Quad Cities IL 2 4481 5914Indian Point NY 2 4467 6096La Salle IL 2 4323 6978Salem DE 2 4281 6918


What is the Right Way to Make the Measurement?What is the Right Way to Make the Measurement?

Start with the Systematics and Work Backwards…Start with the Systematics and Work Backwards…

CHOOZ Systematic Errors, Normalization

Near Detector

Identical Near and Far Detectors

Movable Detectors

Veto and Neutron ShieldCHOOZ Background Error

BG rate 0.9%

Statistics may also be a limiting factor to the sensitivity.


Movable Detector ScenarioMovable Detector ScenarioThe far detector spends about 10% of the run at the near site where the relative efficiency of the two detectors is measured head-to-head.

The detectors must be well underground to reduce the cosmic rate.

So the near and far sites need to be connected by a tunnel!


Detector

Tun

nel W

all

Larger version of CHOOZ (smaller KamLAND)

• Homogenous Volume

• Viewed by PMT’s

• Gadolinium Loaded, Liquid Scintillator Target

• Pure Mineral Oil Buffer

In the Movable Scenario

• Rail System for Easy Transport

• Carries Electronics and Front-end DAQ.

Detector DesignDetector Design


Systematic Error from BackgroundsSystematic Error from BackgroundsAt sites with more than one reactor there is no reactor off running, so other ways of measuring the backgrounds are needed.

The toughest background comes from fast neutrons created by cosmic ’s. They can mimic the coincidence signal by striking a proton and then capturing.

1. Build it deeper (hard to do!)

2. Veto ’s and shield neutrons (effective depth)

3. Measure the recoil proton energy and extrapolate into the signal region.

Veto Detectors

p

n

n


Conclusions and ProspectsConclusions and Prospects• The physics of sin2213 is interesting and important.

• An international proto-collaboration has been formed to work towards a proposal by 2005 (and a white paper this fall).

•The search for a suitable reactor site is underway.

• Controlling the systematic errors is the key to making this measurement.

• Reactor sensitivities are comparable off-axis and the two methods are complementary.

• With a 3 year run, the sensitivity in sin2213 could reach 0.01 (90% CL) at m2 = 2.5×10-3.


Degeneracies


JJ and several others:

neutrino factory Golden + silver (taus) + likely existing info from superbeam will solve ambiguities.


Ekin

Time

Neutrino Factory: the Japanese Scenarionow more thoroughly simulated based on FFAG

physics all the way:low E muonsg-2 muons, low energy NuFact, 20 GeV NUFACT…

Other notable difference wrt US and EU scheme Energy for capture is higher (0.4 +- 0.2 kinetic GeV) (50 GeV proton source + optimization)

SUPPORTED!

COOLING is not necessary….but brings a factor in intensity of >> 2! Japan (Osaka & KEK) are active members of MICE!


Muon Physics Programs & Staging Scenario

Pion Capture (MECO) Muon LFV

Neutrino Factory Muon Collider

Muon Factory-II (PRISM-II) Muon EDM

◆High Power Proton DriverMuon g-2

Muon Factory (PRISM) Muon LFV

Muon g-2

Physics outcomesat each stage


Yoshi Mori NB: a standard cyclotron would be MUCH smaller and inexpensivebut would have much smaller acceptance and could not be scaled upto higher energies.


Yoshi Mori

PRISM=Phase Rotated Intense Slow Muon sourcePRISM=Phase Rotated Intense Slow Muon source

PRISM

Specifications muon intensity: 1011~1012

/sec central momentum: 67-120

MeV/c momentum width: 3 % (<---

30 % ） phase rotation

PRISM ring construction has been approved.

PRISM ring construction has been approved.

approx 5 M$


US MC (Neutrino Factory and Muon Collider collaboration)

highlights*** target studies already advertised. mercury jet in beam mercury jet in B field to get both is a problem: where and how???? JHF / Isolde…

***RF studies in magnetic fields Important for MICE (rf noise in spectrometer) Important for NUFACT (cooling channel with high emittance muon beam going through RF while being contained in magnetic field (phase rotation or cooling) studies so far with 800 MHz, construction of 200 MHz cavity now started!

nice study of cooling in gas H2 filled cavities. (R. Johnson)

*** replace induction linacs with RF phase rotation (Neuffer) (cost saving!)

*** cooling rings works (on paper)! main problem : the injection and ejection kicker


US MC (Neutrino Factory and Muon Collider collaboration)


sizeable improvement in the level of dark current using Be windows



Kicker studies (Palmer)


TOWARDS WORLD STUDY III

Rob Edgecock took initiative (triggered by MUG) to initiate a ‘world study III

… trigger is EU FP6 design study request.

… all three regions agree to collaborate.

Aim is: 1. Design Report by LHC start up. 2. reduce cost of neutrino factory by factor of 2.

steering group formed etc….


MICE

Experiment passed International Peer Review Panel successfully‘strongly recommends approval’

Experiment under funding review in the UK: [10 M£ or 15 M£]

this means we will be going around looking for cryogenics, RF power sources, beam magnets, etc…

RAL management has authorized construction work to begin in the experimental hall at RAL

MICE IS HAPPENING!


- STEP I: 2006

STEP II: summer 2006

STEP III: winter 2007

STEP IV: spring 2007

STEP V: fall 2007

STEP VI: 2008

If funding is adequate, the following sequence of events can be envisaged:


first results from miniboonefirst results from MUSCAT!theta13 prospectives (reactor proposals!) the issue of degeneraciesbeta beam getting close in performance to neutrino factory?!Nufact: death of bow-tie

machine part: MICE strongly recommended – in approval pathstatus of target status of RF cavity studiesstatus of accelerator design FFAG!!!! Cooling ring!!!!to cool or not to cool?cost saving hopes

WORLD STUDY III

synergies: emphasis on low energy muon and high intensity physics

personnal reflexions:Europe’s strengthstwo avenues for Europe: when should we chose?

NUFACT03 Highlights

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Summary of Nufact-03 Alain Blondel NuFact 03 5th International Workshop on Neutrino Factories &...

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