Transcript ISS-detectors

ISS-detectors
Missions:
“Evaluate the options for the neutrino detection systems
with a view to defining a baseline set of detection
systems to be taken forward in a subsequent
conceptual-design phase”
-->This talk
“Provide a research-and-development program
required to deliver the baseline design 
Funding request for four years of detector R&D
“2007-2010” (but more likely “2008-2011”)
-->Paul Soler
The nice thing with neutrino beams is that one can have more
than one detector on the same beam line!
ISS-4 22 August. 2006 IRVINE Alain Blondel
Organization
Detector ‘council’ (i.e. steering group)
role: ensure basic organization, and monitors progress wrt objectives
Alain Blondel (Geneva)
Alan Bross (Fermilab)
Kenji Kaneyuki (ICRR)
Paolo Strolin (INFN)
Paul Soler (Glasgow)
Dave Wark (Imperial)
Mauro Mezzetto (Interface with physics)
http://dpnc.unige.ch/users/blondel/detectors/detector-study.htm
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Water Cerenkov Detectors
Working groups
Kenji Kaneyuki, Jean-Eric Campagne
Magnetic Sampling Detectors
Jeff Nelson --> Anselmo Cervera
http://dpnc.unige.ch/users/blondel/detectors/magneticdetector/SMD-web.htm
TASD Malcolm Ellis
Large Magnet Alan Bross
Liquid Argon TPC
http://www.hep.yorku.ca/menary/ISS/
Scott Menary, Andreas Badertscher, Claudio Montanari,
Guiseppe Battistoni (FLARE/GLACIER/ICARUS’)
Emulsion Detectors
http://people.na.infn.it/~pmiglioz/ISS-ECC-G/ISSMainPage.html
Pasquale Migliozzi
Near Detectors
http://ppewww.ph.gla.ac.uk/~psoler/ISS/ISS_Near_Detector.html
Paul Soler
Detector Technology will be associated with detector type for now
dedicated detector technology session at ISS2
in 22
KEK
Jan06.
ISS-4
August.
2006 IRVINE
Alain Blondel
ISS detector mailing list (78)
ISS-4 22 August. 2006 IRVINE
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Executive summary: I. baseline detectors
beam
Far detector
R&D needed
sub-GeV
BB and SB
(MEMPHYS, T2K)
Megaton WC
photosensors!
cavern and
infrastructure
1-2 GeV
BB and SB
(off axis NUMI, high
g BB, WBB)
no established baseline
TASD (NOvA-like)
or
Liquid Argon TPC
or Megaton WC
Neutrino Factory
(20-50 GeV,
2500-7000km)
~100kton magnetized
iron calorimeter (golden)
photosensors and
detectors
long drifts,
long wires, LEMs
straightforward
from MINOS
simulation+physics
studies
+ ~10 kton
non-magnetic ECC (silver) ibid vs OPERA
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Executive summary
II. beyond the baseline,
(but should be studied)
beam
Far detector
R&D needed
sub-GeV
BB and SB
(MEMPHYS, T2K)
Liquid Argon TPC
(100kton)
clarify what is the
advantage wrt
WC?
1-2 GeV
BB and SB
(off axis NUMI, high
g BB)
no established baseline
Neutrino Factory
(20-50 GeV,
2500-7000km)
platinum detectors!
large coil around
TASD
Larg
ECC
engineering study
for magnet!
simulations and
physics evaluation;
photosensors,
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2006drift,
IRVINE etc…
Alain Blondel
long
Executive summary:
III: near detector, beam instrumentation
beam
BI, ND
R&D needed
sub-GeV BB and SB
(MEMPHYS, T2K)
concept
simulations
T2K example…. CONCEPT
for precision measurements? theory
1-2 GeV BB and SB
(off axis NUMI, high g
BB)
NOvA example..
CONCEPT for
precision measurements?
Neutrino Factory
(20-50 GeV,
2500-7000km)
beam intensity (BCT)
beam energy +polarization
beam divergence meast
shielding
leptonic detector
hadronic detector
ibid
need study
-need study
need concept
simul+study
simul+study+
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detAlain
R&D
ISS-detector report
-- draft -1 exists, (17 pages) available from detector Web page.
-- will be in LateX
will be augmented with
-- executive summary and description of baseline recommandations
-- section on very large air-core magnetic volumes
-- section on Larg research in the US
-- section on detector technology
-- section outlining the R&D efforts required
proposed deadline for new input: 15 october
will be edited, corrected and harmonized to be ready by end of 2006.
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Highlights
1. WATER CHERENKOV
-- First cost estimate of Frejus Megaton detector
-- T2KK idea
2. MAGNETIZED IRON CALORIMETER
-- realistic design and cost estimate
-- revision of golden analysis ==> much better efficiency at low Energy
3. LARGE MAGNETIC VOLUME
-- a new concept
-- MECC detector could demonstrably do platimum channel
4. Liquid Argon
-- impressive R&D efforts (long drift, long wires)
5. systematic related discussions
-- matter effect for NUFACT
-- nuclear effects for Low Energy beam
6. Began first simulations of NuFACT near detectors
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review of far detector options
-- Water Cherenkov
-- Liquid argon (non magnetic)
-- magnetized iron calorimeter
-- ECC
-- large magnetic volumes
-- for TASD
-- for ECC
-- for liquid argon
-- detector technology
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Water Cerenkov
-- can be made in very large volumes (already SK =50kton)
-- very well known technology
-- other applications: proton decay, low energy natural neutrinos,
atmospheric, solar and SN neutrinos, Gadzook, etc…
-- cannot be magnetized easily
-- pattern recognition limited to 1 ring events (--> sub GeV neutrinos)
-- baseline detector for sub-GeV neutrinos.
-- three projects around the world: HK, UNO, MEMPHYS
-- community organized and coordinated in its own
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WC report for ISS from
Chang Kee Young(UNO)
Kaneyuki (HyperK)
Campagne (MEMPHYS)
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The MEMPHYS Project
65m
CERN
130km
65m
Water Cerenkov modules at Fréjus
Fréjus
4800mwe
CERN to Fréjus
Neutrino Super-beam and Beta-beam
Excavation engineering pre-study has been done for 5 shafts
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MEMPHYS: Main results of the preliminary study
Best site (rock quality) in the middle of the mountain, at a depth of 4800 mwe
Cylindrical shafts feasible:  = 65 m and a height h = 80 m (≈ 250 000 m3)
 215 000 tons of water (4 times SK)
- 4 m from outside for veto and fiducial cut 146 000 tons fiducial target
3 modules would give 440 kilotons Fid. (like UNO) BASELINE
estimated excavation cost ≈ 80 M€ X Nb of shafts
this number should be >~ doubled for photo-detectors, electronics and other
infrastructure
(--> >~500 M€ for three shafts = 440 kton fiducial)
-- >~G€ for a megaton --
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The T2HK project
• Tunnel-shaped cavity
• Avoid sharp edges. Spherical
shape is the best
• Twin cavities
• MFD/MTOT worse than single
cavity. But…
• Two detectors are independent.
One detector is alive when the
other is calibrated or maintained
• Staging approach is possible
• The Tochibora mine is considered as a candidate site: very good rock quality
• Photosensors: PMT long-term stability proven, but too expensive. Photosensors:
time production too long. How to reduce it?
• 13” HPD prototype under test at Tokyo U.
• in Japan detector R&D for Mton WC will start this fall( FJ-PPL)
• T2KK part of the plans.
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Possible experimental set-up
Total cost must
be similar to the
baseline design.
2.5 deg. off axis
2.5 deg. off axis
Distance from
the target (km)
JPARC
2.5deg.off-axis beam @Kamioka
Off-axis angle
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NB about 300 Oku-Yen should be included for the beam upgrade
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comments
The physics reach of WC detectors is well advanced and based on the solid bases of
previous successful projects. Furthermore, it is very wide (SPL and/or BB, ATM,
Solar, SN, proton decay,…)
Assuming the availability of the needed budget and no correlation with the T2K/Nova
results, 2020 seems to be a realistic date for the start of data taking. In case of
correlation a 5 years delay is possible.
Given that ATM neutrinos are for free and help a lot in solving degeneracies, it is
mandatory to include them in all calculations
An issue is the R&D on photodetectors:
Costs should be reduced. HPD are promising. For the time being the better PE/MeV cost is given by 12” PMT
Production rate should be optimized. At present it lasts 10 years the production of all PMTs for 1Mton
detector. Storage space could become a problem
MEMPHYS project: it seems that once the ATM  are included the SPL performs
better than BB (assuming equal sys errors. Optimistic?). Maybe the BB adopted for
the Frejus is not the optimal choice.
MEMPHYS + SPL+BB gives excellent performances but it is very
expensive, perhaps in the same ballpark as NuFACT
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-- Liquid Argon TPC:
This is the particle physics equivalent of superstrings:
DOE (detector of everything)
it can do everything, can it do anything BETTER?
(than a dedicated standard technique)
to be quantitatively demonstrated case by case.
impressive progress from ICARUS T600
recent highlights
-- effort at FERMILAB (FLARE)
-- 2 efforts in EU ICARUS and GLACIER
-- observation of operation in magnetic field
-- programme on-going to demonstrate long drift, or long wires
talks by Badertscher, Menary, Rubbia
INFN ICARUS were contacted and added to mailing list with no further result.
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US Larg effort (Menary)
Implementation of Larg detector in Globes underway
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Finally, What about at 990 km From Fermilab
(Furthest Canadian Site)?
Here, 20 mrad is the minimum off-axis
angle allowed (since central axis of the
beam is some 16 km above the surface
at this point).
cycling on d..
0--> 2p --> etc
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considerable noise reduction can be obtained
by gas amplification
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non- trivial liquid argon consumption!!!!
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height is limited by high voltage
1kV/cm  2 MV for 20m…
field degrader in liquid argon tested 
(Cockroft-Greinacher circuit)
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and drift under high pressure
in pressurized cryostat
long drift will be tested
in 5m vertical drift tube
(ETHZ-Napoli)
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Install ARGONTUBE at the U. of Berne
Budget for digging hole allocated, excavation during Summer
2006!
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NEUTRINO FACTORY DETECTORS
An ideal detector exploiting a
Neutrino Factory should:
Identify and measure the charge of the muon (“golden
channel”) with high accuracy
Identify and measure the charge of the electron with
high accuracy (“Platinum channel”)
Identify the  decays (“silver channel”)
Measure the complete kinematics of an event in order
to increase the signal/back ratio
Migliozzi
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-- Magnetic segmented detector:
this is a typical NUFACT detector for E>>1.5 GeV
e  m
GOLDEN CHANNEL
experience from MINOS &NOvA
designs prepared for Monolith and INO
iron-scintillator sandwich with sci-fi + APD read-out
proposed straightforward design 90kton for ~175M$.
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Magnetized Iron calorimeter
(baseline detector, Cervera, Nelson)
B = 1 T  = 15 m, L = 25 m
t(iron) =4cm, t(sc)=1cm
Fiducial mass = 100 kT
Charge discrimination down to 1 GeV
Event rates for 1020 muon decays (<~1 year)
Baseline
732 Km
3500 Km
m CC
e CC
108
2 x 108
4 x 106
7.5 x 106
m signal (sin2 q13=0.01)
3.4 x 105
3 x 105
(J-PARC I SK = 40)
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A Strawman Concept for a Nufact
Iron Tracker Detector (Jeff Nelson)
15m diameter polygon
Triangular liquid scintillator cells
4 piece laminate
Can be thin if planes
interconnected
Structure based on NOvA using
MINERvA-like shapes
4cm x 6cm cells (starting point)
3mm thick PVC walls
Looped WLS fibers & APDs
e.g. down to 1cm
Idea from 1st NOVA Proposal
60kA-turn central coil
A sample would look like
0.5m x 0.5m
Average field of 1.5T
Extrapolation of MINOS
1 cm Fe
0.7 cm PVC
3.3 cm LS
2/3rds Fe; ρ ≈ 2
Based on 175M$ for 90kt
NB: in fact it is not best to go to
iron:scint=1:4 cm
6 cm
Dp/P is better by 20% for
iron:scint= 4:2 cm
4 cm
--> probably more mass/better cost possible
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Iron (4cm) + active (1cm)
NUFACT detector studied so far:
This ‘conceptual detector’
was used for the sensitivity studies.
Performance from MINOS proposal
CUTS optimized for low q13 limits
with cut-off at muon energy of 5 GeV
resulting signal efficiency:
Monolith
at 3000 km,
1st max is at 6 GeV
2d max is at 2 GeV
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at 3000 km,
1st max is at 6 GeV
2d max is at 2 GeV
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New analysis (Cervera)
OLD:
Pm> 5 GeV
NEW: Lm > Lhad + 75cm
(shown for three different
purity levels down to << 10-4 )
new analysis
old analysis
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Location
of22INO
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INO Detector Concept
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Construction of RPC
2 mm thick spacer
Two 2 mm thick float Glass
Separated by 2 mm spacer
Pickup strips
Glass plates
Resistive coating onISS-4
the outer
surfaces of glass
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Underground Cavern
Experimental Hall
Layout of the Underground Cavern
Size of the experimental hall
150 m X 22 m X 30 m
Parking & Storage
Access tunnel
Experimental Hall
orientation wrt the incoming beam?
Electronics
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FAR SITES
Without calling specifically for candidate far detector sites we received
two contributions of far sites that would welcome a neutrino factory beam
1. Pihäsalmi Finland (Juha Peltoniemi)
2. INO Indian Neutrino Observatory (PUSHEP at Tamilnadu) Naba Mondal
we also know of Canary Islands
This is a subject that will need to be pursued
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-- Emulsion detector:
this is a typical NUFACT detector for the
silver channel
E>>10 GeV
e  
experience from OPERA
silver channel has opposite sign d dependence
than golden
--> solving ambiguities, test unitarity.
By necessity less precise
than golden channel.
Here 5kton ECC combined with
+ 40 kton LMD
only tau--> muon decay channel
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 trigger and locate the neutrino interactions
 muon identification and momentum/charge measurement
ECC emulsion analysis:
Electronic detectors:
Target
Trackers
Pb/Em.
target
Vertex, decay kink e/g ID, multiple
scattering, kinematics
Spectrometer
Pb/Em. brick
Link to muon ID,
Candidate event
8m
Basic “cell”
Extract selected
brick
Brick finding, muon ID, charge and p
8 cm
Pb Emulsion
1 mm
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p/pISS-4
< 20%
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LARGE MAGNETIC VOLUME
Observing the platinum channel
or the silver channel for more decay channels
requires a dedicated Low Z and very fine grained detector
immersed in a large magnetic volume
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Multiple Solenoids - Conceptual Layouts
Magnetic Tunnel

15 m x 15 m x 15m modules; B = 0.5T
Magnetic Cavern
Magnet
Steel

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4
1.2 Totally Active Scintillation Detector
Camilleri, Bross
10 solenoids next to each other. Horizontal field perpendicular to beam
Each: 750 turns, 4500 amps, 0.2 Tesla. 42 MJoules . 5Meuros.
Total: 420 MJoules (CMS: 2700 MJoules)
50 turns
Coil: Aluminium (Alain: LN2 cooled).
Possible magnet schemes for TASD


Problem: Periodic coil material every 15m:
Increase length of solenoid
along beam?
rd
How thick?
3 International Scoping Study Meeting
Rutherford Appleton Laboratory
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Options
 Technologies

Room temperature Cu or Al conductor – Well, maybe

Power dissipation is high and field is relatively low
– But I will consider it

High Tc superconductor – NO*



At this point in time for the same Ampere-Turns: 200X more
expensive than convention SC
*However, development progress in recent years has been
rapid so the situation could change in the near (5 yr) future.
Conventional SC



Lots of experience, but this size is new.
Technically – certainly doable
BUT WHAT IS THE COST?
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3
Cost Extrapolations for Baseline NF Detector
ONE Magnet
 Cost via stored energy


Stored energy  340 MJ
From Green and Lorant

C(M$)  0.5(340)0.662  24M$
 Cost via Magnetic Volume

From Green and Lorant

C(M$)  0.4(.5 X 3400)0.635  45M$
 Reference Point – CMS Solenoid


C(M$)  0.5(2700)0.662  93M$ (Stored energy)
C(M$)  0.4(4 X 370)0.635  41M$ (Magnetic volume)
 Most Optimistic Extrapolation

Use stored energy and conclude formula overestimates by factor
of 1.7 (93/54) based on CMS case

Then NF magnet extrapolated cost – 14M$
 Most Pessimistic Extrapolation

Use magnetic volume and conclude formula underestimates by a
factor of 1.3 (54/41) based on CMS case

Then NF magnet extrapolated cost – 60M$
conventional SC magnet:
X 10 Magnets
=140-600M$
8
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Also considered was a conventional Al magnet. Cost = ~50 M$, but
power cost is about 10-30 M$ a year.
Clearly a more detailed estimate would be highly worthwhile to
understand what is the best way to build a large magnet on the walls of
a large underground cavern.
SC Magnets of this size can certainly be built, but better cost
estimates will only come after some real engineering analysis
6-12 month effort
It could be very expensive and unpractical
therefore this is not considered to be a baseline
nevertheless it seems very worthwhile to study.
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Conclusions II
 At this time it appears that a large volume air-core
magnetized detector for a neutrino factory is not
feasible from cost considerations, but is certainly
technically feasible
 R&D aimed at the mechanical engineering issues is
required to see if the costs can be reduced.
 Developments in high Tc SC could change this
picture



Reduction in cost of the high Tc conductor itself
Possibility for non-vacuum insulated vessels (Icarus
example) for SC operating at 77K
There is a long way to go to make this viable
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15
x ~ a few X0=14cm….
B > 0.5 T
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Magnetized ECC structure
target
4.5 cm, 2 X0
spectrometer
shower absorber
Electronic det:
e/p/µ separator
&
“Time stamp”
35 stainless steel plates emulsion films
Rohacell® plate
We have focused on the “target + spectrometer” optimization
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µ end electron momentum resolution:
3 gaps (3cm thick) and 0.5 T
µ
electron
For the electron only hits associated to the primary electrons used in the
parabolic fit (Kalman not used)
Given the non negligible energy loss in the target, the electron energy is taken
downstream for the comparison of true against reconstructed
FIRST CONVINCING DEMONSTRATION THAT THE PLATINUM CHANNEL COULD
BE USED!
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Magnetized fully active detector
first simultation studies (M. Ellis)
e-mu PID
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SYSTEMATICS related topics
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A revealing comparison:
A detailed comparison of the capability of observing CP violation was performed
by P. Huber (+M. Mezzetto and AB) on the following grounds
-- GLOBES was used.
-- T2HK from LOI: 1000kt , 4MW beam power,
6 years anti-neutrinos, 2 years neutrinos.
systematic errors on background and signal: 5%.
-- The beta-beam 5.8 1018 He dk/year 2.2 1018 Ne dk/year (5 +5yrs)
The Superbeam from 3.5 GeV SPL and 4 MW.
Same 500kton detector
Systematic errors on signal efficiency (or cross-sections) and bkgs are 2% or 5%.
--NUFACT 3.1 1020 m+ and 3.1 1020 m+ per year for 10 years
100 kton iron-scintillator at 3000km and 30 kton at 7000km (e.g. INO). (old type!)
The matter density errors of the two baselines (uncorrelated): 2 to 5%
The systematics are 0.1% on the signal and 20% on the background, uncorrelated.
all correlations, ambiguities, etc… taken into account
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d  [00-900 ]
d  [900-1800 ]
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NB: 3sigma = 60 means that +-1 sigma = +-3.50
d  [1800-2700 ]
d  [2700-3600 ]
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What do we learn?
1.
matter effect for NUFACT
Both (BB+SB+MD) and NUFACT outperform e.g. T2HK on most cases.
2. combination of BB+SB is really powerful.
3. for sin22q13 below 0.01 NUFACT as such outperforms anyone
4. for large values of q13 systematic errors dominate.
Matter effects for NUFACT, cross-sections for low energy beams.
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This is because we are at first maximum or above,  CP asymmetry is small!
for NUFACT:
 work on systematic errors on
matter effect
A preliminary study was made by
E. Kozlovskaya, J. Peltoniemi, J. Sarkamo,
The density distribution in the Earth along
the CERN-Pyhäsalmi baseline and its effect
on neutrino oscillations. CUPP-07/2003
the uncertainties on matter
effects are at the level of a few%
J. Peltoniemi
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Errors in density
ISS-3 at RAL Warner
location
length
“a priori”
“best”
Continental
2500 km
4.7%
2.9%
Oceanic
2500 km
2.6%
1.7%
Continental
9000 km
2.0%
1.7%
Oceanic
9000 km
1.8%
1.5%
Errors are ~2 sigma
(errors not really Gaussian)
Recommendations
Avoid:
• Alps
• central Europe
• thick crust (e.g. Fenoscandia)
• Europe to Japan
Recommendations
Best profiles:
• Western Europe to Eastern US
• Atlantic Islands (Canaries, Maderia,
Azores) to Portugal, western Spain, NW
France, southern Ireland, western
England
Such a study,
in collaboration with geophysicists
will be needed for candidate LBL sites
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-- Near detectors and flux instrumentation
-- flux and cross-section determinations
-- other neutrino physics
a completely new, yet essential aspect of
superbeam, beta-beam and neutrino factory
NO PERFORMANCE EVALUATION SHOULD BE TAKEN
SERIOUSLY UNTIL THE NEAR DETECTOR CONCEPTS HAVE
BEEN LAYED DOWN!
Soler, Sanchez tomorrow
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near detector constraints for CP violation
ex. beta-beam or nufact:
P(em) - P(em)
P(em) + P(em)
= ACP a
sind sin (m212 L/4E) sin q12 sin q13
sin2 q13 + solar term…
e diff. cross-section*detection-eff *flux and ibid for bkg
BUT: need to know m and m diff. cross-section* detection-eff
Near detector gives
with small (relative) systematic errors.
knowledge of cross-sections (relative to each-other) required
knowledge of flux!
interchange role of
e
and
m for superbeam
ISS-4 22 August. 2006 IRVINE
Alain Blondel
experimental signal= signal cross-section X efficiency of selection + Background
 sig     + B
need to know this:
e
m
e
m
 sig /  sig
 sig /  sig
this is not a totally trivial quantity as
there is somethig particular in each of
these cross-sections:
for instance the effects of muon mass
as well as nuclear effects are different for
neutrinos and anti-neutrinos
while e.g. pion threshold is different for
muon and electron neutrinos
and of course the fluxes… but the product flux*sig is measured in
the near detector
ISS-4 22 August. 2006 IRVINE
Alain Blondel
3.5 GeV SPL
g  100 b-beam
-- low proton energy:
no Kaons  e background is low
--region below pion threshold
(low bkg from pions)
but:
low event rate and
uncertainties on cross-sections
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Uncertainties in the double ratio (Sobczyk at RAL meeting)
1. problem comes from compound of
Fermi motion and binding energy
with the muon mass effect.
R
 ( m )
,
 ( e )
R
 ( m )
 ( e )
the double ratio calculation is very insensitive to variations of parameters … but
ISS-4 22 August. 2006 IRVINE
Alain Blondel
 ( m )
 ( e )
DR 
 ( m )
 ( e )
at 250 MeV (first maximum in Frejus expt) prediction varies from 0.88 to 0.94
according to nuclear model used. (= +- 0.03?)
Hope to improve results with monochromatic k-capture beam
ISS-4 22 August. 2006 IRVINE
Alain Blondel
FLUX in NUFACT will be known to 10-3
see NUFACT YELLOW REPORT
this was studied including
-----
principle design of polarimeter, and absolute energy calibration
principle design of angular divergence measurement
radiative corrections to muon decay
absolute x-section calibration using neutrino – electron interactions
ee
(event number etc… considered)
this is true for
e
m
e
m
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Near
detector
and beam
instrumentation
5. Near
Detector
Beam
Spectra at NUFACT



Near detector(s) are some distance (d~30-1000 m)
from the end of straight section of the muon storage ring.
Muons decay at different points of straight section: near detector is
sampling a different distribution of neutrinos to what is being seen by the
far detector
If decay straight is L=100m and
Different far detector baselines:
?
?
?
730 km, 20 m detector: q~30 mrad
2500 km, 20 m detector: q~8 mrad
7500 km: 20 m detector: q~3 mrad
Cherenkov
BCT
shielding
Polarimeter
storage ring
d
d =30 m, at 8 mrad, lateral
displacement of neutrinos is
0.25-1.0mm to subtend same angle.
the charm and DIS detector
the
leptonic detector
International Scoping Study
ISS-4
UC Irvine, 21 August
200622 August. 2006 IRVINE
18
Alain Blondel
Inverse muon decay
Inverse muon decay: scattering off electrons in the near detector
(Karadzhov, Tsenov)
 m + e -  e + μ -
νe + e -  ν μ + μ -
Simulation of a cylindrical detector with radius 1 m, thickness 30 cm
and density 1.032 g/cm3(scintillator, total mass ~1 ton)
105 events per year.
==> flux and a detector simulations -- ongoing
ISS-4 22 August. 2006 IRVINE
Alain Blondel
5. Near Detector Event Spectra
d=30 m, r=0.5 m
Event rates Anti-
m
25.5 GeV
d=130 m, r=0.5 m
26.6 GeV
d=1km, r=0.5 m
37.1 GeV
e
32.5 GeV
22.3 GeV
23.2 GeV
International Scoping Study
UC Irvine, 21 August 2006
ISS-4 22 August. 2006 IRVINE
20
Alain Blondel
6. Near Detector Design
Possible design near detector around UA1/NOMAD/T2K magnet
EM calorimeter
Hadronic
Calorimeter
Muon chambers
International Scoping Study
UC Irvine, 21 August 2006
23
main aim is to measure the charm crosssection (dominant Bkg to golden channel)
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Detector Technology Development for Neutrino
Detectors (Bross)
At the ISS meeting at KEK we had a very interesting session
on detector technologies relevant to neutrino detectors
Current Status
Near-term R&D goals
There was a common thread to almost all the talks – photo
sensors and fiber optics
Applications primarily for TASD and Water Cerenkov
TASD – WLS fiber readout of scintillator and the photo sensor
Water Cerenkov – Need for VERY large Area Photocathode coverage
In particular
Hybrid PMT
Kuraray Fiber
Status and techology
Metal-Resistive-Semiconductor APD/SiPMT/Multi-Pixel-PhotonCounter
ISS-4 22 August. 2006 IRVINE Alain Blondel
Visible-Light-Photon-Counter
HYBRID PMT
The Principle of HAPD
Main idea of HAPD:
Replace dynodes of PMT with an avalanche diode
photon
HV
Bias
cf. PMT
photocathode
photo electron
(p.e.)
Bombardment Gain
(~4500@20kV)
dynodes
Avalanche Gain
avalanche diode
(AD)
(~20 or more)
Multiple gain stages in
dynodes
ISS-4 22 August. 2006 IRVINE
Alain Blondel
A ‘half-scale’ prototype
208 mm (~8-inch)
Al coating
2 rings
C. JORAM -- CERN
Development in collaboration with
Photonis-DEP, C. Fontaine et al.
77
MRS/SiPMT/MPPC
All are Si avalanche photodiode based on similar technology
For readout of WLS fibers
Offer opportunity for high gain - potentially very low cost photon
counter
Commercial processing technology
High packing density
Currently QE is relatively low, but R&D points to improvement
possibilities
Room temperature or near room temperature (-20C) operation
possible
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Principles of MRS APD operation
CPTA, Moscow (MRS APD)
MePhi/PULSAR, Moscow (SiPM)
Dubna
Multipixel Geiger mode APD’s
invented in Russia in 1980’s
Number of pixels
 450 - 4000
limited Geiger mode
PMT: diameter 20 mm
MRS: active area 1x1mm2
diam 1 mm
Depletion region  2mm
Drift velosity  107 cm/s
Field  (2-3)x105 V/cm
Qpixel = Cpixel x V = Cpixel x (Vbias - Vbreakdown)
6 electrons
Cpixel  50fmF V  few voltsISS-4
 22QAugust.
pixel  2x10
2006 IRVINE
Alain Blondel
MRS APD
- Diameter of active area
- Number of pixels
- Geometrical efficiency
- Photon detection efficiency
at th=0.5 p.e. and dark rate ~1MHz
- Bias voltage range
- Gain
- Sensitivity to magnetic field ( 9T)
- Cross talk
- Auto calibration and control
- Dark noise rate (th =0.5 p.e)
New devices
- Dark noise rate
- PDE
- Dynamic range, linearity of signal
- Temperature effects
- Long time stability
- Lifetime
- Recovery time
1.1 mm
556
70-80 %
10-15%
25-75 V
106 - 107
no
4-6%
separated p.e. peaks
 1 MHz
LED signal
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Multi-Pixel-Photon-Counter
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Multi-Pixel-Photon-Counter
Operation
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Visible Light Photon Counter
The Visible light Photon Counter is an impurity
band avalanche photodiode that operates in
the range of 6-10K
Parameters (from D0 program)
QE = 85%
Gain = 35k-65k
Noise = 10-50 kHz (@1 pe threshold)
Most-Importantly: COST
For the D0 program (approximately 120k pixels
(1mm) the per channel cost for the VLPC system
(packaged, tested, delivered) was $60/Ch
ISS-4 22 August. 2006 IRVINE
Alain Blondel
D0 VLPCs
VLPC  6th Generation
High QE  80%
Low noise <5X104 Hz
(@1 pe)
High Rate capability
>40 MHz
High production yield
 70%
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Recent VLPC R&D
Gen VII – New AR Coating
D0 VLPCs used quarter wave SiO2 AR coating
>10% reflection loss
Gen VII uses Silicon nitride
Should improve VLPC QE to >95% @525nm
Gen VII - Scratch Coating
D0 VLPCs had exposed AL traces
Resulted in minor die losses due to handling
Over coating traces will eliminate this loss
ISS-4 22 August. 2006 IRVINE
Alain Blondel
New Wafer - Gen VII
3 X 3 (3mm X 3mm)
4X8 (.5mm)
2X4 (1 mm) [D0]
1 cm2 single pixel
16X16 (.5mm)
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Close-UP, 2X4(1mm pixel), 4X8, 16X16 element
arrays
ISS-4 22 August. 2006 IRVINE
Alain Blondel
Latest VLPC – Gen VII
Conclusions on VLPC R&D Program
Grew 80 wafers - can be fabricated for about $150k! (New
Vendor)
This is the epitaxial growth step:
$0.1/1 mm pixel
• Note D0 cost was $2/pixel!
We estimate that the epitaxial wafers can be processed for
about $2-3k/wafer
About $0.3/1 mm pixel
We expect yields of 90% (to be determined in upcoming tests)
D0 Yield was 70%
New material is 5 to 10X more uniform than the D0 material and
the defect density is 50X smaller
1 mm pixel cost at wafer level <$0.5/pixel!
ISS-4 22 August. 2006 IRVINE
Alain Blondel
CONCLUSIONS -I
The ISS detector task assembled in a new fashion a range of
activities that are happening in the world.
A number of new results were obtained and baseline detectors
were defined.
For low energy beams, the Water Cherenkov can be considered as
baseline detector technology at least below pion threshold. An
active international activity exists in this domain.
1Mton~(0.5-1) G€
For medium energy (1-2 GeV) there is comptetiton and it is not
obvious which detector (WC, Larg or TASD) gives the best
performance at a given cost.
ISS-4 22 August. 2006 IRVINE
Alain Blondel
CONCLUSIONS II
For the neutrino factory a 100 kton magnetized iron detector can
be built at a cost of <~200 M$ for the golden channel.
New analysis of low E muons should improve sensitivities.
An non magnetic Emulsion Cloud Chamber (ECC) detector for tau
detection can straightforwardly be added with a mass of >~5 kton
There is interest/hope that low Z detectors can be embedded in a
Large Magnetic Volume. At first sight difficulties and cost are
very large. However this should be actively pursued. Electron sign
determination up to 10 GeV has been demonstrated for MECC, and
studies are ongoing for Liquid Argon and pure scintillator detector.
ISS-4 22 August. 2006 IRVINE
Alain Blondel
CONCLUSIONS III
Near detector, beam instrumentation and cross-section measurements are
absolutely required. The precision measurements such as CP constitute a
new game wih respect to the present generation.
For the super-beam and beta beam the near detector and beam diagnostic
systems need to be invented.
There is a serious potential problem at low energy due to the interplay of
muon mass effect and nuclear effects. A first evaluation was made at the
occasion of the study.
NUFACT flux and cross sections should be calibrated with a precision of
10-3. An important design and simulation effort is required for the near
detector and diagnostic area. (shielding strategy is unknown at this point)
Finally matter effects were discussed with the conclusion that a
systematic error at 2% seems achievable with good collaboration with
geologists.
ISS-4 22 August. 2006 IRVINE
Alain Blondel
CONCLUSIONS IV
The next generation of efforts should see a first go at the
design effort and R&D towards the design of precision neutrino
experiments
There is a motivated core of people eager to do so and this
activity should grow.
THANKS!
ISS-4 22 August. 2006 IRVINE
Alain Blondel