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Physics Working Group
INTERNATIONAL NEUTRINO FACTORY AND SUPERBEAM SCOPING STUDY MEETING RAL – 25 April, 2006 Y. Nagashima OSAKA UNIVERSITY
Status, prospects and what to do here
Acknowledgements:
Y.Nagashima, ISS060427
Grateful to all ISS speakers from whom I have taken material.
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Council members EU: P. Hernandez, S.King, M. Lindner, K. Long (deputy chair), M. Mezzetto US: D.Harris , W.Marciano, L. Roberts, H.Murayama
Asia: Y.Nagashima (chair) , K. Nakamura, O. Yasuda Four subgroups and conveners
•
Theoretical : S. King
• Phenomenological:
O. Yasuda
• Experimental:
K. Long
• Muon:
L. Roberts (added after CERN meeting)
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Plenary meetings to date: CERN: 22 – KEK: 23 – 24 September, 2005 26 January, 2006 Work shops: (Physics) London: 14 – 21 November, 2005 Boston: 6-10 March, 2006 + Phone meetings ~bi weekly
This presentation is a summary of KEK and Boston meetings Y.Nagashima, ISS060427 3
Mission: Theory Subroup Establish the neutrino physics case
•
Robust arguments for peers
• ‘Elevator pitch’ for decision makers
If you happen to be on an elevator with a powerful senator, can you explain why you want to spend ~B$ on your project in 30 seconds ?
H.Murayama
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H.Murayama
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Many of these questions usually reside
in GUT scale and beyond, 5
It is very difficult to establish a one-to-one correspondence between GUT scale predictions and low energy observables.
A given model, however, usually has generic predictions for low energy observables.
Therefore studying neutrinos allows to gain considerable insight into phenomena which otherwise would be in accessible.
Colliders can not probe this kind of physics, since any effects in scattering amplitudes are suppressed by M GUT , ~O(10 -10 ) at LHC !
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S.King, P.Huber
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Top down approaches
•Connection with String theory
( P.Langacker
) Minimal see-saw unlikely.
Motivates extended see-saw such as double see-saw and type II (triplet Higgs).
•The Origin of Flavor
Can be tested experimentally Predicted by theory S. King L.Everett
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More on SUSY
Broken Flavor symmetry
Mass Hierarchy and small mixing in quarks and charged leptons suggests hidden symmetry .
Symmetry broken by a VEV
~0.02
m ~ u : m c : m t ~ m d 2 : m s 2 : m b 2 m e 2 : m
m
2 : m
t
2 ~
4 :
2 : 1 H. Murayama
Neutrino Many neutrino models Different from quark sector ?
M u
~ 4
M u
2 3 ~ 3 2 4 3 2 Y.Nagashima, ISS060427 2 3 1 2 , 1 2
d
~ ,
M
3
d
2 ~ 3 3 2 2 Generation 3 3 2 2 , 3 2 ,
l M
l
3 ~ 2 3 3 2 3 2 2 2 2 2 2 , ,
M
1 1 1 1 1 1 1 1 1
More on neutrino mass
Bottom up approaches
* Quark-Lepton Complementarity: Minakata : A.Smirnov inNOVE03 * Experimental test if New reactor experiment?
Gadolinium-loaded SK?
More on mixing Precision comparable to LBL : S. Choubey P.Harrison
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M.Fukugita, Tegmark Neutrinos in Cosmology Leptogenesis, Dark matter, Dark Energy Mass from Large Scale Structure
•
Now ∑ m
i < 0.4 eV
•
Future
s
(∑ m
i ) ~ 0.04 eV
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Mass varying neutrino
(D.Marfatia)
• •
The neutrino couples to light scalers
• A possible candidate for Dark Energy. • Explains all existing data with one sterile neutrino,
yet predicts no LSND effect A possible signal:
D
m 2 (K2K) ≠
D
m 2 (Atmosphere)
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Mission – Phenomenological Subroup
Look for new physics, survey models and determine necessary precision to: test the unitarity and/or NSI (non standard interaction)
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Status of 3+2 scheme
(Note: 3+1 scheme unlikely ) Can accommodate all data Implies: Too low BG for superbeams, wrong near detector non-osc. assumption Eventually checked by MiniBOONE !?
If confirmed: Some new interesting physics: M. Sorel
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Unitarity triangles for lepton sector
In see-saw mechanism: 6x6-Matrix unitary; in all realistic scenarios: Matter effects change unitarity triangles Example: Higher E makes sides comparable; Easier to calculate area Easier to establish CP viol.
Z.Xing
Z. Xing
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More on unitarity S.Geer
J.Lopez
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Non Standard Interaction:
A.Friedland
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Another reason to do silver channel
( e t )
More on new physics predictions S.Antusch
O.Yasuda
Muon physics subgroup:
Lepton-flavour violating processes – clear synergy with neutrino oscillations Neutrino Factory could provide copious source of muons for:
•
Rare decays: Y.Kuno
Current proton drivers: 10 8 muons/s (MEG) •
Flavour-change in scattering
4 MW PD: 10 11-12 muons/s (PRISM) Y.Nagashima, ISS060427 NF Frontend: 10 14 muons/s 16
Y.Kuno
J.Hisano
x Y.Nagashima, ISS060427
More on muon phys.
L.Roberts
K.Jungmann
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Physics with High Energy Muon beam LFV in DIS processes Slepton mixing (SUSY) introduces LFV at one loop
t
-associated LFV interesting for Higgs-boson mediated processes Use DIS process:
m
O(10 N -> 2
t
X at neutrino factory ) events for 50 GeV Also possible with neutrino beam (in preparation) Kanemura
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Mission: Experimental subgroup:
Use realistic assumptions on the performance of accelerator and detector to: Evaluate and compare performances of Superbeam Beta beam Neutrino factory First: Recent Progress on Facilities at Large
q
13
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Non-Accelerator Physics
Blaidwood Reactor Experiment in US 2-detctors P.Fisher
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More on
2b
decay
VLBNO All parameters in one experiment ?
As good as any other SB experiments.
Use wide band beam to measure both 1 st and 2 nd W.Marciano; Slides: T.Kirk
Also H.Kirk, this conference maximum
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T2KK
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
sin 2 2
q
13 =0.05
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Reminder: Studies before ISS
SB outperforms NF at large
q
13 Very little study on Beta Beam Poor knowledge on systematics
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Beta Beam study
Facilities using a Water Cherenkov detector E.Couce
Principle advantage of beta beam: No intrinsic beam BG High gamma beta beam best alternative (even “ low flux ” )
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Comparisons:
d
CP -
q
13
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P. Huber et al.
SB still outperforms BB and NF At large
q
13 More on BB E.Couce
M.Mezzetto
E.Fernandez
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For small
q
13
(<0.01)
Superbeams will not address
q
13 , mass hierarchy, or CP violation A clear case for NF and/or
b
-beam Yet, many people take an attitude “ Wait until what SB finds, NF is useful only for small
q
13 ” However, Will we get the funds to get a neutrino factory even if all previous investments end up “ unsuccessful ” ? (de Gouvêa: )
ISS060427
Investigate NF performance at high
q
13
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Huber, Lindner, Rolinec, Winter
Factory Optimization
Use a Better Detector 100 kton, magetised iron Two performance assumptions : Threshold more important than resolution
‘
Better’: – Threshold – Resolution
‘
Baseline ’: – Threshold – Resolution
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Huber, Lindner, Rolinec, Winter
factory with better detector
q 13
sensitivity vs L Better detector threshold makes L=2000-3000 km very efficient
q
13 baseline for exclusion limit Better Threshold
“Magic baseline” Y.Nagashima, ISS060427 28
Huber, Lindner, Rolinec, Winter, to appear
Optimization for large
q
13
? : E vs L
Mass hierarchy no problem for L >> 1000 km CP fraction for CP violation (3
s):
“ Standard ” “ Optimal appearance” L=1000 km/E
m
=20 GeV looks good
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More on NF W.Winter
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Better detector: Large
q
13
.
W
Can compete with the superbeam upgrades (prel.) Both better Eres and threshold useful at large
q
13 Large
Dr
+better detector prefers shorter baselines (1000-2000km); E
m
small OK
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l d e n
Golden + (Silver, Platinum) Improves sensitivity to CP violation at large
G o
Requires its own baseline?
q
13 P.Hube
r Now we have a good handle to make NF competitive at large
q
13 Need to demonstrate with realistic detectors !!
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W.Winter
Interactions: Physics-Detector
“ Close the loop Better detector = key component in large Need best possible detector with 1. Better low energy efficiences 2. Better energy resolution?
Understanding of systematics is critical.
Crosssections, Backgrounds, matter distribution, etc.
At large
q q
13 13 , it is the limiting factor.
In addition: discussion!
e ” detection, silver channel concepts etc.
Consider what physics the near detector can do ?
Good place for new physics ?
More on Y.Nagashima, ISS060427 Matter effects crosssection D E, and E th
J.Peltoniemi
M.Warner
J.Sobczyk
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Interactions: Physics-Accelerator
Physics: What muon energy really required?
40 GeV enough for
q
13 ,
d
CP , mass hierarchy ?
W.Winter
Physics: How large can flux uncertainty be?
• Storage ring+possible NF program? m + silver m m + m Y.Nagashima, ISS060427 MB
More on flux, E spectrum
m
phys. requirement J,Campagne L.Roberts
K.Jungmann
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•Avoid too many options mixed up • Discuss different options in one
section and choose one “representative” for main line of argumentation?
Need that representative here at RAL if we are to finish in August !!!
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Our goal : ‘to understand the physics of flavour’ Requires high precision, high sensitivity measurements of neutrino oscillations Also LVF in muons, 0
2
b
decay. Next 5 years Improve the precision on the atmospheric parameters Measure sin 2 2
q
13 >0.1, and find CP violation.
Next 10 years Demonstrate visibility of sub-leading transitions: Explore sin 2 2
q
13 down to 0.01
Solve mass hierarchy Then, precision era : when ???????
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Timescales: the challenge
Era of sensitivity & precision Hep-ex/0509019
て Y.Nagashima, ぃ ｓ ｇ
This graph is made by the same people who believe NF is good only for small Hypnotized, be not !
q
13.
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NF roadmap: key decision points
K.Long
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
Neutrino Factory roadmap
International scoping study (ISS) NuFact06 International design study (IDS) ♦ ● ● ● ● ● ● ● ● Neutrino Factory consortium formation Build Physics
Key decision points
Seek to instigate IDS Seek to host FP7 DS and/or I3 bids ♦ ♦ IDS mandate at Nufact06 ♦ Submit FP7 bids ♦ Form Neutrino Factory consorium ♦ Initiate build phase ♦
Ambitious, science-driven schedule Issue now is to establish vibrant R&D programme Vision for International Design Study phase: International collaboration; coordinated effort:
•
Concept development
–
full system
Y.Nagashima, ISS060427 • •
Accelerator R&D Detector R&D 2019 2020
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Summary
We have to show NF is good at large
q
13 , too.
We have to close the loop and come up with a representative plan to achieve the goal in August.
Plan a strategy to accelerate R&D, to achieve early realization of NF.
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Back up slides
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Origin of neutrino mass
Effects of physics beyond the SM as effective operators Can be expanded systematically (Weinberg)
•The origin of neutrino mass lies in the lowest order
effect of physics and thus the most sensitive probe for new physics at high scales.
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SUSYmotivated prediction
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New interactions can happen in three places Transition Detection Production
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Neutrino Oscillation Appearance Probability
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q
13 & beam experiments Appearance probability :
dependences in sin(2 q 23 ), sin( q 23 ), sign( D m 2 31 ), d -CP phase in [0,2 ] q
13 & reactor experiments
•
1-P(
e
e ) = sin 2 (2
q
13 )sin 2 (
D
m 2 31 L/4E) + O(
D
m 2 21 /
D
m 2 31 )
weak dependence in D m 2 21 • a few MeV e + short baselines ISS060427 sin 2 (2 q 13 negligible matter effects (O[10 -4 ] ) ) measurement independent of sign( D m 2 13 ) 45
Conclusions
(Reactors
：
T.Lasserre NO-VE 06)
A new reactor neutrino experiment dedicated to
q
13 is now being
Reactor & Beam programs provide complementary measurements of q 13 An early value of q 13 will help to define the optimum CP d program
Several projects of reactor experiment in the pipelines
First generation
: sin 2 (2 q 13 )~0.02-0.03 Rate + Shape Near/Far normalization error dominates (<1% error) Motionless detectors: Double Chooz, KASKA, RENO
Towards the Second Generation
: sin 2 (2 q 13 )<0.02 Movable detectors : Daya-bay, Braidwood and motionless Triple Chooz Multi-detector phased programs better cross checks
But what is the systematic error induced by moving ‘ 100 tons ’ detectors?
A further increase of the mass
: sin 2 (2 q 13 )<0.01 Movable detectors : Daya-bay, Braidwood Motionless detectors: Angra , Triple Chooz Shape only uncorrelated background dominates !!!
1000 mwe: Daya Bay, Angra Need more mass 450 mwe: Braidwood , Triple Chooz Need more mass + x >5 times better bkg rejection Y.Nagashima, ISS060427 46
Ongoing Experiments “After 5 years
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Super-Beam < 1MW
~4MW Expect to measure 23%
10%
D
m 2 13 : MINOS
2% Find non-zero
q
13
T2K, NOvA sin 2 2
q
13 ~ 10 -2
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Super Beam Phase II
D
m 2 13 sin 2 2
q
13
~10 -3 mass-hierarchy up to sin 2 2
q
13 for 1% all value of
d
~ 10 -2 NOvA Search for CP violation
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Near Future / ”next
10 yrs
”
Super Beam: opportunity
Ｘ
1
０
improvement over ongoing experiments
P.Huber et al., hep-ph/0403068 Y.Nagashima, ISS060427 NO A 49
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Kajita EP2010 Y.Nagashima, ISS060427 53
(Huber, Lindner, Rolinec, Winter, to appear)
Interactions: Detector-Accelerator
3
s
sensitivity to sin 2 2
q
13 Better Eres Better threshold Better Eres+thresh Optimization: Better detector versus higher muon energy?
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Standard
Optimal Detector (better threshold + energy resolution) Mass hier., CP violation Better threshold (especially)
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Better energy resolution Smaller matter density uncertainty (for large
q
13 )
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New physics tests
: P.Huber
Test unitarity and small ad-mixtures of “new physics” by:
t
detection P ee +P e
m
+P e
t
= 1?
(Donini, Meloni, Migliozzi, 2002; Autiero et al, 2004) Neutral currents (hard) (Barger, Geer, Whisnant, 2004) Spectral signature on probability level Example: Damping effects (Blennow, Ohlsson, Winter, hep-ph/0502147)
More complicated: Hamiltonian-level effects (e.g., Blennow, Ohlsson, Winter, hep-ph/0508175) Example: Oscillation-NSI confusion theorem (Huber, Schwetz, Valle, 2002)
Y.Nagashima, ISS060427 See other talks in this workshop for specific possible effects!
E.g. Hisano, Kanemura, Sato, Sorel, Xing 56
Beyond the ISS:
timescales
5 0 3 0 2 0
Mezzetto
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Timescales: the challenge
Era of sensitivity & precision
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Hep-ex/0509019
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Conclusions:
International scoping study: Has become established Is raising, and beginning to address, key issues Report will lay the foundations for the more detailed design-study phase International Design Study of the Neutrino Factory Required to follow the ISS to:
•
Prepare reference (baseline) design by ~2011
•
Prepare first conceptual design by ~2013 In parallel, design studies for alternative facilities carried forward: must To allow best possible facility to be identified The ISS, together with MICE, MERIT, and EMMA An exciting R&D programme … With a first-rate scientific goal be
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