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ISS-detectors. Working group reports. Water Cerenkov Detectors report by Jacques Bouchez Magnetic Sampling Detectors http://dpnc.unige.ch/users/blondel/detectors/magneticdetector/SMD-web.htm report by Alan Bross Liquid Argon TPC http://www.hep.yorku.ca/menary/ISS/ - PowerPoint PPT Presentation
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ISS-2 25 jan. 2006 KEK Alain Blondel
ISS-detectors
ISS-2 25 jan. 2006 KEK Alain Blondel
Water Cerenkov Detectorsreport by Jacques Bouchez
Magnetic Sampling Detectorshttp://dpnc.unige.ch/users/blondel/detectors/magneticdetector/SMD-web.htm
report by Alan Bross
Liquid Argon TPC http://www.hep.yorku.ca/menary/ISS/
reports by Scott Menary, Andreas Badertscher
Emulsion Detectors http://people.na.infn.it/~pmiglioz/ISS-ECC-G/ISSMainPage.html
report by Pasquale Migliozzi
Near Detectors http://ppewww.ph.gla.ac.uk/~psoler/ISS/ISS_Near_Detector.html
reports by Paul Soler and Federico Sanchez
Working group reports
Detector Technology will take place this afternoon
ISS-2 25 jan. 2006 KEK Alain Blondel
Wednesday 25 January
time speaker
14:00 MPPC T. Nakadaira
14 :30 SiPMs for T2K ND280
Y. Kudenko
15:00 New VLPC R&D A.Bross
15:30 Hybrid PMT H. Nakayama
16:00 Scintillating Fiber Production (Kuraray)
Y. Shiomi
16:30 Open discussion
Technology discussion session (organized by Alan Bross and Kenji Kaneyuki)
ISS-2 25 jan. 2006 KEK Alain Blondel
The MEMPHYS Project
65m
65m
Fréjus
CERN
130km130km
4800mweExcavation engineering pre-study has been done for 5
shafts
Water Cerenkov modules at FréjusCERN to FréjusNeutrino Super-beam and Beta-beam
ISS-2 25 jan. 2006 KEK Alain Blondel
A Very Large Laboratory
In the middle of the Fréjus tunnel at a depth of4800 m.w.e a preliminary investigation shows the feasibility to excavate up to five
shafts of about 250,000 m3 each
Henderson
HK
ISS-2 25 jan. 2006 KEK Alain Blondel
65m
~ 4 x SK
65m
Detector basic unit
Detector:
cylinder (a la SK) 65 m diameter and 65 m height: : → 215 000 tons of water (4 times SK)
taking out 4 m from outside for veto and fiducial cut →146 000 ton fiducial target
3 modules : 440 kilotons (like UNO) BASELINE
4 modules would give 580 kilotons (HK)
→Simulations done using 440 kt
each cavity 70 m diameter and 80 m total height
ISS-2 25 jan. 2006 KEK Alain Blondel
ISS-2 25 jan. 2006 KEK Alain Blondel
R&D on electronics (ASICs)
Integrated readout : “digital PM (bits out)”Charge measurement (12bits)Time measurement (1ns)Single photoelectron sensitivity
High counting rate capability (target 100 MHz)
Large area pixellised PM : “PMm2”16 low cost PMsCentralized ASIC for DAQVariable gain to have only one HV
Multichannel readoutGain adjustment to compensatenon uniformitySubsequent versions of OPERA_ROC ASICs
aim at 200 euros/channel
ISS-2 25 jan. 2006 KEK Alain Blondel
Mechanics & PMT tests
Basic unit that we want to build and test under water
Electronic box water tight
IPNO
Taken in charge by IPNO: well experienced in photodetectors (last operation: Auger). With PHOTONIS tests of PMT 8”, 9” 12” and Hybrid-PMT and HPD
ISS-2 25 jan. 2006 KEK Alain Blondel
A possible schedule for MEMPHYS at Frejus
Year 2005 2010 2015 2020
Safety tunnel Excavation
Lab cavity ExcavationP.S Study
detector PM R&D PMT production
Det.preparation InstallationOutside lab.
Non-acc.physics P-decay, SN
Superbeam Construction Superbeam
betabeam Beta beamConstruction
decision for cavity digging decision for SPL construction decision for EURISOL site
ISS-2 25 jan. 2006 KEK Alain Blondel
SUPERBEAM BETABEAM
→ e e →
→ e e →
Superbeam + beta beam together
2 ways of testing CP, T and CPT : redundancy and check of systematics
2 beams
1 detector
2yrs
8yrs
5yrs
5yrs
pure4 flavours + K
ISS-2 25 jan. 2006 KEK Alain Blondel
MEMPHYS comments (AB)
-- French neutrino community strongly motivated-- R&D already started. -- CERN beams (Beta-beam, Superbeam) possible please consider oscillation physics performance with BOTH betabeam gamma=100 AND WBB Superbeam Ep= 3-4 GeV. (no Kaons) ball-park est. cost of total package
600M€ (detector) + + (from erlier est…) betabeam (~500M€) + superbeam (~400 M€)
main physics question mark: is it possible at all to do the physics with low energy events ?
J. Bouchez promised to investigate the principle of a near detector system to determine cross-sections and efficiencies for the four flavours of neutrinos as function of energy.
ISS-2 25 jan. 2006 KEK Alain Blondel
ISS-2 25 jan. 2006 KEK Alain Blondel
considerable noise reduction can be obtained by gas amplification
ISS-2 25 jan. 2006 KEK Alain Blondel
industrial study of large Tank 70 m diameter, 20 m drift = 100 kton of Larg shown to be feasible conceptually
ISS-2 25 jan. 2006 KEK Alain Blondel
non- trivial liquid argon consumption!!!!
ISS-2 25 jan. 2006 KEK Alain Blondel
height is limited by high voltage 1kV/cm 2 MV for 20m…
field degrader in liquid argon tested (Cockroft-Greinacher circuit)
ISS-2 25 jan. 2006 KEK Alain Blondel
long drift will be tested in 5m vertical drift tube (ETHZ-Napoli)
and drift under high pressurein pressurized cryostat
ISS-2 25 jan. 2006 KEK Alain Blondel
consequences of long drift: time integration
1. Detector must be underground to limit cosmics (are they all just muons?)
2. photomultipliers sensitive to 128 nm scintillation light can be installed for trigger
3. however Raleigh scattering (<1m scattering length) limits position reconstruction from light timing
4. it is possible to tag timing of neutrino events with precision small wrt 100 ns. and operate with both mu+ and mu- trains injected in storage ring
ISS-2 25 jan. 2006 KEK Alain Blondel
ll-
l+
ex: race track geometry:constraint:
¦l- - l+¦ > l +
where is the precision
of the experiments time tagplus margin
Muons of both signs circulate in opposite directions in the same ring. The two straight sections point to the same far detector(s). OK
There is one inconvenient with this: the fact that there are two decay lines implies two near detectors.
In addition this does not work for the triangle.
this can be solved by
dog bone ortwo rings with one or more common straights
ISS-2 25 jan. 2006 KEK Alain Blondel
ISS-2 25 jan. 2006 KEK Alain Blondel
NB B field is perp. to drift!NBB: what range of electrons does this correcpond to?
ISS-2 25 jan. 2006 KEK Alain Blondel
ISS-2 25 jan. 2006 KEK Alain Blondel
ISS-2 25 jan. 2006 KEK Alain Blondel
Questions:
what is efficiency as a function of energy vs B field?
what magnetic field is necessary to have reasonable efficiency for electrons up to first oscillation maximum and a little more? (this is of course a baseline dependent statement)
phenomenologists: be prepared to add this to the perfect detector! 10 (100?) kton with 30% efficiency for wrong sign electrons up to 5 GeV ? dreams?
High Tc supra conductor magnet?
ISS-2 25 jan. 2006 KEK Alain Blondel
ISS-2 25 jan. 2006 KEK Alain Blondel
US Larg effort (Menary) Implementation of Larg detector in Globes underway a few weeks to go!
ISS-2 25 jan. 2006 KEK Alain Blondel
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 (“time reversal of the golden channel”)
Identify the decays (“silver channel”)Measure the complete kinematics of an event in
order to increase the signal/back ratioMigliozzi
ISS-2 25 jan. 2006 KEK Alain Blondel
“MECC” structure
Stainless steel or Lead Film Rohacell
DONUT/OPERA type target + Emulsion spectrometer + TT + Electron/pi discriminator
B
Assumption: accuracy of film by film alignment = 10 micron (conservative)
13 lead plates (~2.5 X0) + 4 spacers (2 cm gap) (NB in the future we plan to study stainless steel as well. May be it will be the baseline solution: lighter target)
The geometry of the MECC is being optimized
3 cm Electronic detectors/ECC
ISS-2 25 jan. 2006 KEK Alain Blondel
Momentum resolution for muons
ISS-2 25 jan. 2006 KEK Alain Blondel
Charge misidentification
ISS-2 25 jan. 2006 KEK Alain Blondel
Estimate of showering electrons
ISS-2 25 jan. 2006 KEK Alain Blondel
Momentum resolution vs zvertex
ISS-2 25 jan. 2006 KEK Alain Blondel
q-mis vs zvertex
Given the true-hit based reconstruction, the quoted charge misidentification can be seen as an lower limit. Anyhow it is a good starting point!
the real question will be how many right signs appear as wrong sign!
ISS-2 25 jan. 2006 KEK Alain Blondel
Outlook
Study the perf ormance of a stainless steel target Detailed study of the way how to magnetize the detector Defi ne a realistic baseline f or the e/ discriminator: its
choice depends on the total target mass, the TT width (i.e. how many evts per brick), the costs, …
Finalize the electron analysis: the e/ separation and the charge reconstruction
Check the sensitivity to the “golden” (the muon threshold is at 3 GeV!)
A full simulation of neutrino events is mandatory in order to evaluate the oscillation sensitivity and provide the input f or GLOBES
We plan to perf orm a fi rst exposure of a MECC on a charged beam at CERN this year
Migliozzi
ISS-2 25 jan. 2006 KEK Alain Blondel
Basic Detector Concept
7.5 mm
15.0 mm
Considered Extremely Fined Grained
segmented magnetic detector (Bross)
ISS-2 25 jan. 2006 KEK Alain Blondel
Magnetic Field
? Has not been investigated in any detail yet.? Considering two options:
– Iron sheets in between scintillator layers.? Parameters to study are thickness of each sheet and ratio of
scintillator to iron.? More work needed to understand how to accurately simulate
the field and perform reasonable reconstruction.– Air toroid magnet surrounding detector.
? ATLAS magnet is a starting point in terms of scale.? Simulating 0.15 T field to start. ? Will study physics parameters (P resolution, charge ID, etc)
as a function of magnetic field
ISS-2 25 jan. 2006 KEK Alain Blondel
Muon
3 GeV/c
ISS-2 25 jan. 2006 KEK Alain Blondel
Electron
ISS-2 25 jan. 2006 KEK Alain Blondel
Momentum Resolution
ISS-2 25 jan. 2006 KEK Alain Blondel
Is this Detector Scenario Credible?? Technology is not really an Issue
– COST IS? Assume a 25kT all scintillator detector with air-core
magnet (B = 1-3 kG)– Of course the study will also include magnetized Fe
? Much larger Fiducial mass– Or could add non-active target in air-core design
? Scintillator (Solid or Liquid) – No R&D issues– Cost (solid) - $100M
? Segmentation as shown here gives X 106 ch– $10/ch is possible - $70M
? Fiber Cost – Assume high QE PD and high yield scint. Use 0.4mm fiber– $0.16/m $16M (Very important optimization – 1 mm fiber is
6X the cost!)? $100M for magnets + infrastructure, etc? Total is something less than $300M
– Not an order of magnitude more than what is acceptable
ISS-2 25 jan. 2006 KEK Alain Blondel
3. Flux normalisation (cont.)3. Flux normalisation (cont.)
Rates:— E = 50 GeV
— L = 100 m, d = 30 m— Muon decays per year: 1020
— Divergence = 0.1 m/E
— Radius R=50 cm
100 m
Yearly event rates
High granularity in inner region
that subtends to far detector.
E.g. at 25 GeV, number neutrino
interactions per year is:
20 x 106 per 100 g/cm2.
With 50 kg 109 interactions/yr
ISS-2 25 jan. 2006 KEK Alain Blondel
3. Flux normalisation (cont.)3. Flux normalisation (cont.) Neutrino flux normalisation by measuring: Signal: low angle forward going muon with no recoil Calculable with high precision in SM
Same type of detector needed for elastic scattering on electrons:
ee
)LABin(2)( 2
22
22
EmG
mq
msG
dy
edeF
W
WFCC
ee ee
)()(
ee )()(
)1(22 ymE ee E.g. CHARM II obtained value of sin2W from this
24
22
2
)1(sinsin2
1)(y
sG
dy
edWW
FNC
24
22
2
1sinsin2
1)(y
sG
dy
edWW
Fe
ISS-2 25 jan. 2006 KEK Alain Blondel
4. Muon polarization4. Muon polarization Fit neutrino spectrum for polarization:
Compare fitted polarization to measured one from polarimeter:
ISS-2 25 jan. 2006 KEK Alain Blondel
5. Cross sections5. Cross sections
Measurement of cross sections in DIS, QE and RES. Coherent Different nuclear targets: H2, D2
Nuclear effects, nuclear shadowing, reinteractions
With modest size targets can obtain very large statistics
What is lowest energy we can achieve? E.g. with LAr can go down to ~MeV
ISS-2 25 jan. 2006 KEK Alain Blondel
F . S a n c h e z ( U A B / I F A E ) I S S M e e t i n g , D e t e c t o r P a r a l l e l M e e t i n g . J a n 2 0 0 6
F u n c t i o n o f a n e a r d e t e c t o r
ee
ee
EffBNEffBN
EffBNEffBNA
//)(//)(
//)(//)(
• B a c k g r o u n d s a r e g e n e r a t e d b y e l e c t r o n n e u t r i n o s , n e u t r i n o s ( o r m i s - r e c o n s t r u c t e d m u o n n e u t r i n o s w h e n e v e r t h e e n e r g y r e c o n s t r u c t i o n i s i m p o r t a n t ) . P r e c i s e k n o w l e d g e o f e l e c t r o n a n d 0
p r o d u c t i o n p r o c e s s e s a r e c r u c i a l b o t h f o r N C a n d C C r e a c t i o n s .
• I f fl u x i s m e a s u r e d w i t h a p a r t i c u l a r c h a n n e l : = N / i t i s n o t e n s u r e d t h a t t h e t e r m B c a n c e l s t h e u n c e r t a i n t i e s i n
• T h e e ffi c i e n c i e s c a n b e d i ff e r e n t f o r n e u t r i n o s a n d a n t i -n e u t r i n o s . P r e c i s e k n o w l e d g e o f b a s i c k i n e m a t i c s b e h a v i o r o f t h ei n t e r a c t i o n i s i m p o r t a n t ( W , q 2 , E d e p e n d e n c i e s , p a r t i c l e s p r o p e r t i e s i n t h e h a d r o n i c h a l f o f t h e r e a c t i o n ) .
ISS-2 25 jan. 2006 KEK Alain Blondel
F.Sanchez (UA B/IFA E) IS S M eeting, Detector Paralle l M eeting. Jan 2006
CC Q uasi-elast ic
• Knowledge of CC-Q E cr oss-sect ion is poor .
• I t is also not cover ing t he t hr eshold. T his could be impor t ant f or low ener gy neut r ino exper iment s.
ISS-2 25 jan. 2006 KEK Alain BlondelF .S a n c h e z ( U A B / IF A E ) IS S M e e t in g , D e te c to r P a r a lle l M e e t in g . J a n 2 0 0 6
T h e over al l c r os s s ec t ions f or CC1 (w it h t h e W ? 2 G eV c ut ) :
nln
pln
plp0
CC- 1
I t is not w e l l meas ur e d and i t d e pend s on t h e W c ut (h igh er mas s r es onanc es –up t o 18 - and non- r es onant r egion)
threshold will be different for e and mu, affected by fermi motion, reinteractions and Q2 distribution (neutrino antineutrino)
ISS-2 25 jan. 2006 KEK Alain Blondel
F.Sanchez (UAB/IFAE) ISS Meeting, Detector Parallel Meeting. Jan 2006
Nuclear eff ects• Fermi motion and Pauli
blocking aff ect the cross-section at low q2
and also introduce and additional smearing in the reconstruction of neutrino energy.
ISS-2 25 jan. 2006 KEK Alain Blondel
F.Sanchez (UAB/IFAE) ISS Meeting, Detector Parallel Meeting. Jan 2006
Remarks• The near detector is f undamental to achieve design goals of
Neutrino Factory and Beta Beams.• Personal prejudices:
– Similar target Far/ Near.– Exclusive channel measurements. – Possibility of changing neutrino spectrum.– Measure exclusive reactions.– Flux, is it possible to measure it f rom elastic scattering on electrons?.– The problem of energy scale!.– Problem of reaction threshold’s.
• Design is driven by Far detector needs: – WHAT ARE THE EXPECTED BACKGROUNDS? – HOW TO NORMALI ZE FLUX?– HOW TO MEASURE ENERGY?. WHI CH PRECI SI ON?.– …
• Watch at improvements in neutrino interactions f rom theorist (NuI nt conf erence series) and experiments (Minera & f uture T2K).
• Some of these conclusions do not apply if large energy neutrinosare studied (> 4/ 5 GeV).
ISS-2 25 jan. 2006 KEK Alain Blondel
6. Charm Production6. Charm Production Remember that main background to golden
channel is production of charm: Qt = P sin2 cut eliminates backg at 10-6
...,,,, 00 csDDDD
not detected
De
e
De e
NC
CC
Hadron decay
Can use near detector to measure Pt and Qt distribution of charm, if we can reconstruct explicitly:
With silicon detector can reconstruct more than 106 charm states per year
Cervera et al.
ISS-2 25 jan. 2006 KEK Alain Blondel
6. Charm (cont.) 6. Charm (cont.) NOMAD-STAR silicon detector was able to reconstruct 45 charm
events in NOMAD. Measured charm rate:
Fully active silicon target (ie. 52 kg with 18 layers of Si 500 m thick,
50 x 50 cm2 =4.5 m2) for full charm event reconstruction. Optimal design: fully pixelated detector (e.g. Monolithic Active Pixels MAPS)
ISS-2 25 jan. 2006 KEK Alain Blondel
Next steps
0. everyone to produce web site and mailing list
1. develop simulation of detector with justified level of simplification for performance evaluation. (no need to have full simulation to evaluate charm decays in flight!)
2. develop tool to evaluate performance:GLOBES input files in form of eficiency for neutrino type to be detected as event class i
i E, P, QT)
(NB limitation is that all types and classes must have same energy binning)
3. begin to think of R&D developments and experiments to be performed, (preferably on real neutrino physics experiments)
4. cost model mass term + B-field term + 3 sigma charge confusion at 1.5 GeV muon or 6 GeV electron
5. delegate one rep/group to the physics meeting in Boston
ISS-2 25 jan. 2006 KEK Alain Blondel
7X7 table for each Ev , y , (x?)
ISS-2 25 jan. 2006 KEK Alain Blondel
near detector
Set-up a generic simulation of a near detectorDefine a series of potential detector geometries to run on near detector-- dedicated purely-leptonic detector for absolute fluy-- quasi-elastic , pi, pi0 detector with variable targets (a la T2K ND280)-- charm detector for NufactCarry out physics studies needed for the ISS report:
1. Study flux normalisation through: 2. Use quasi-elastic and elastic interactions to determine neutrino
spectrum3. Reconstruct muon polarization from spectrum4. Sensitivity for cross-section measurements: low energy?5. Determination of charm: remember this is main background for
golden channel!6. ….suggestions ….
ee
ISS-2 25 jan. 2006 KEK Alain Blondel
ISS- detector video conferences 14:00 GMT
23 february16 march13 april
Detector group will delegate 1 person per sub-group to physics meeting in Boston
already known to be invited for next meeting at RAL
Juha Peltoniemi: (Oulu Mine)
Jan Sobczyk: (Wroclaw –theorist- low energy interactions)
Introduction: Pasquale Migliozzi
Summary: Paul Soler
THANKS to ALL!