Transcript Physics potential of very long neutrino factory baselines

Physics and Performance
Evaluation Group: Status and plans
IDS-NF Plenary meeting
RAL, United Kingdom
January 17, 2008
Walter Winter
Universität Würzburg
(somewhat biased view) on behalf of the executive committee:
Andrea Donini, Patrick Huber, Silvia Pascoli, Walter Winter,
Osamu Yasuda
Contents
PPEG mandate
 Status and IDS baseline
 Test of alternative setups:
The PPEG‘s playground
 Comparison to competitors
 Website, Euronus
 Plans
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IDS Physics and Performance
Evaluation Group (PPEG)
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… will continue the activities of the ISS physics working group.
First phase: focus on the performance of the various neutrino
facilities.
At a later stage: focus shifted towards the physics case for a
neutrino factory
Executive committee: Andrea Donini, Patrick Huber, Silvia
Pascoli, Walter Winter, Osamu Yasuda
Tasks:
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Coordinate physics performance study
Website
Interface with accelerator and detector WG
(possibly) Workshops
Report
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From ISS to IDS
ISS physics
Theory
IDS PPEG
Here?
Optimization/
parameters for
standard
physics
Experimental
Muon physics
REPORT
Additions for
NS physics/
requirements
for muon
experiments
TIME
Phenomenology
Concise physics case
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Why need another physics WG?
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Physics performance
evaluation (initial phase)
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Baseline design has to be evaluated and further
developed in discussion with other WGs
Evaluation of new ideas, especially for large q13,
such as NF+SB, NF-SB, off-axis NF, etc.
Comparison to alternatives: beta beams etc.
Define requirements for non-standard physics
measurements, e.g., silver channel, etc.
Include requirements for muon physics and how
these interact with the oscillation program
…
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Physics performance evaluation
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Main purpose of the PPEG:
Evaluate the physics performance of a given experimental
setup (neutrino factory or other, existing or planned) in a
transparent, consistent and documented fashion.
Transparent: Clearly state
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Definition of performance indicator
Approximations used
Chosen input parameters, luminosity etc.
Confidence level
Treatment of systematics
Consistent: Assumptions should be on equal footing
Documented: Relevant information will be archived and
will be accessible. Use of a website.
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Definition of parameters
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Neutrino factory setup: all the parameters are defined in
strict collaboration with the detector and accelerator WG
of the IDS
 Need of a defined and efficient communication
between the various WGs (steering group?)
There will be different types of setups:
a) Baseline setup: stable, agreed design
b) Conservative modification of 1. – e.g. different baseline etc.
g) Speculative ideas, e.g. new ideas
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Beta beam setups: possibly follow a similar procedure as
for neutrino factory, working in collaboration with betabeam groups; yet undefined!
Super-beam setups: use of existing literature and input of
well-established and recognized experts
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Status
First version of baseline setup evaluated
 First version of webpage online
 Start of discussion of requirements for nonstandard physics
 Keep track of new developments, such as
low-E neutrino factory
 Keep track of „competitors“, e.g.,
achievable beta beam luminosities
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IDS baseline setup
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IDS baseline 0.10
evaluated!
P. Huber
(plenary)
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IDS baseline: Luminosity
Luminosity ~
Useful muon
decays x
detector mass x
running time
 Luminosity critical
for
Accelerator
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Detector(s)
– Physics potential
– Optimization
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IDS baseline: other critical parameters
Detection efficiency
versus backgrounds:
Is it better to have smaller
BGs (small q13?) or higher
efficiencies (large q13?)
 How small can the
threshold be?
 Impact of systematics?
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IDS baseline iteration procedure?
… from the PPEG point of view
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Avoid quick changes; changes should be adiabatic
Change request from working group as a whole
Twice-a-year (?) review of baseline setup by
steering group?
Each change with significant impact on physics
potential has to be justified
Session in plenary meeting devoted to discussing
changes of baseline?
Specific responsible persons from each WG?
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b/g-setups: The PPEG‘s playground?
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PPEG needs some mechanism to evaluate and
compare to
– Modifications/the optimization of the IDS baseline
from the physics point of view
– New developments (such as low-E neutrino factory)
– Competitors
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Here: b-setups for modifications (such as different
baseline), g-setups for new developments
The mechanism how to choose competitor setups
(superbeams, beta beams) needs some refinement,
possibly in collaboration with Euronus
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Example (b): Choice of std. baselines?
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How does that look
like for IDS baseline?
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(Kopp, Ota, Winter, in prep.)
All regions:
Sensitivity for
sin22q13>10-4.2 (5s)
for the shown
performance
indicator
Compared to IDS
baseline: ~ factor 2
higher luminosity,
Em =50 GeV
Robust optimum for
~ 4000 + 7500 km
(not <= 3000 km!)
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Example (b): Minimum Em for NSI?
High-E NF
IDS baseline?
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High-E NF
IDS baseline?
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Higher muon energy helps; low-E NF not an option
Silver channel: Not relevant for IDS baseline; helps for Em ~ 50 GeV
(Kopp, Ota, Winter, in prep.)
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Example (g): Low-energy NF
(5 years)  (3  1020 useful decays/yr)  (2 signs)
 (20Kt fid. Mass) = 31022 Kt-decays (2 signs)
BASIC:
Excellent
threshold!
BETTER: (10 years)  (5  1020 useful decays/yr)  (2 signs)
 (20Kt fid. Mass) = 11023 Kt-decays (2 signs)
Em ~ 4 GeV
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Red (no backgrounds)
– Dotted - 1 X 1023 KT-years
– Solid – 3 X 1022 KT-years
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Black (Background @ 10-3)
– Short dash - 1 X 1023 KT-years
– Long dash – 3 X 1022 KT-years
Talk by Alan Bross
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Comparison to
„competitors“: Superbeams
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Superbeam upgrades could
compete with neutrino factory
for large q13
For large q13, CP violation is
the only relevant matter!
But, Huber: Super-beams are
„super“ not only because of
the target power, detector
mass etc., but also because of
the price!
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Talk by
P. Huber
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Beta beams: Luminosity?
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ISOL method at 1-2 GeV (200 kW)
201
– >1 1013 6He per second
– <8 1011 18Ne per second
– 8Li and 8B not studied
– Studied within EURISOL
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+
spallation
1 GeV p
Fr
fragmentation
+
Talk by
M. Lindroos
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n
p
U
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Li
fission
143
+
X
+
Cs
+
Y
Direct production
– >1 1013 (?) 6He per second
– 1 1013 18Ne per second
– 8Li and 8B not studied
– Studied at LLN, Soreq, WI and GANIL
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Production ring
– 1014 (?) 8Li
Factor of 10
beyond current
– >1013 (?) 8B
std. luminosities?
– 6He and 18Ne not studied
– Will be studied in the future
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RAL January 2008
The beta-beam task, EURISOL
Beta-beam requirements, 18
Higher g beta beams
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g ~ 350 CERN
implementation
with two baselines
q13 = 5º
2000km +
7000km
d = 0, 90, -90º
7000km
Normal Hierarchy
Peak of spectrum ~
matter resonance E
7000km
Inverted Hierarchy
“Nominal” 2·1018 decays/year
“Medium” 5·1018 decays/year
“Ultimate” 10·1018 decays/year
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E. Fernandez-Martinez
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Systematics task force?
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Knowledge on cross
sections better for high
than low neutrino
energies
Talk by M. Sorel
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Important issue especially
for superbeams
How does that look like
for a neutrino factory?
What SG/BG
uncertainties do we
expect?
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From P. Huber‘s talk
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PPEG Website
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The PPEG has already
setup a website:
http://www.ippp.dur.ac.uk/ids/
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Webpage to do:
– Incorporate and document IDS baseline;
possibly: glb-files (GLoBES), curves as data?
– Discuss and document b and g setups
– Cross-links to useful documents?
– Move together with main IDS site???
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Connection
to Euronus
A. Donini
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Questions to be addressed
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Robustness of conclusions wrt luminosity etc.?
Does the far baseline detector have to be as good as
MIND? What about the luminosity splitting?
Why did the performance become worse for large q13?
How to fix that?
Two baseline optimization?
Minimum muon energy for NSI, silver channel, near
detector physics (such as pol. structure functions)?
Physics case for silver detector?
Large q13 strategy: how to deal with Double Chooz etc.?
Include more theory people to support physics case?
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Plans until NuFact
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Update website
Two-baseline optimization, NSI requirements
Check baseline: performance for large q13, etc.
Possibly add figures for other performance
indicators (such as q23, Dm312)
Follow developments for beta beams, superbeams,
etc.
Possibly provide figures for different detector
systematics (BG versus threshold)
Possibly provide figures with competitor
comparison
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Summary and conclusions
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Mandate: Continutation of ISS, focus on physics
performance
First version of ISS baseline evaluated
Baseline optimization, muon energy requirement
have to be checked
Several procedure/strategies should be thought
over:
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Baseline iteration (with other WGs)
Large q13 strategy
Physics case for the ECC
Selection of competitor setups
Inclusion of theory at earlier stage?
Create a „systematics task force“?
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How does that relate
to Euronu?
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