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The Gran Sasso laboratory and theneutrino beam from CERN
Eugenio Cocciacoccia@lngs.infn.it
Erice 2 september 2006
Content
• The Gran Sasso Laboratory
• Neutrino physics activity
• The Cern to Gran Sasso neutrino beam
• First events
• Perspectives
Underground Laboratories
Very high energy phenomena, such as proton decay and neutrinoless double beta decay, happen spontaneously, but at extremely low rates. The study of neutrino properties from natural and artificial sources and the detection of dark matter candidates requires capability of detecting extremely weak effects.
Thanks to the rock coverage and the corresponding reduction in the cosmic ray flux, underground laboratories provide the necessary low background environment to investigate these processes.
These laboratories appear complementary to those with accelerators in the basic research of the elementary constituents of matter, of their interactions and symmetries.
LABORATORI NAZIONALI DEL GRAN SASSO - INFN
Largest underground laboratory for astroparticle physics
1400 m rock coveragecosmic µ reduction= 10–6 (1 /m2 h)underground area: 18 000 m2
external facilitieseasy access756 scientists from 24 countriesPermanent staff = 70 positions
Research lines• Neutrino physics (mass, oscillations, stellar physics)• Dark matter• Nuclear reactions of astrophysics interest• Gravitational waves• Geophysics• Biology
Evidence of neutrino oscillation
GALLEX / GNO - solar νMACRO - atmospheric ν
Unique cosmic ray studies
EAS-TOP with LVD
LNGS most significant results with past experiments
PRESENT EXPERIMENTS
Solar ν LunaBorexino
ν fromSupernovaeLVDBorexinoICARUS
Dark MatterDAMA/LIBRA; CRESST
WARP; Xenon test
ν beam fromCERN:OPERA
ββ decay and rare eventsCuoricinoCUORE; GERDA
Fundamental physicsVIP
GravitationalWavesLisa test
Occupancy
Borexino
OPERA
HALL CHALL B
HALL A
LVD
CRESST
CUORE
CUORICINO
LUNA2DAMA/LIBRA
GENIUS-TF
MI R&DXENON
ICARUS
GERDAWARP
VIP
LOW ACTIVITY LAB
LISA
BAM - OPERA
• Upgrade of the ventilation system • Upgrade of the cooling capability• Upgrade of the electrical power
2004 - 2005 - 2006Important safety and infrastructures upgrade of the Laboratory
• Floor waterproofing • Realization of containment basins • Safety measure for the drinkable water
LVD Large Volume Detector
2 - 5 SN/century expected in our Galaxy.Plan for multidecennial observations
1000 tons liquid scintillator + layers of streamertubes
300 ν from a SN in the center of Galaxy (8.5 kpc)
Running since 1992
SN1987A
Collab.:Italy, Brazil, Russia, USA, Japan
Early warning of neutrino burst important for astronomical observations with different
messengers (photons, gravitational waves)SNEWS = Supernova Early Warning System
LVD, SNO, SuperK in future: Kamland, BOREXINO
1000 billions ν in 20s from the SN coreMeasurement of neutrinos spectra and time evolutionprovides important information on ν physics and on SNevolution.Neutrino signal detectable from SN in our Galaxy orMagellanic Clouds
Large Volume Detector• 3 identical towers in the detector
• 35 active modules in a tower
• 8 counters in one module
Super-Super-Kamiokande Kamiokande (10(1044))Kamland Kamland (330)(330)
SNO (800)SNO (800)MiniBooNE MiniBooNE (190)(190)
Tra parentesi Tra parentesi ilil numero numero didi eventi eventi dada una una SN alSN alcentro dellacentro della Galassia Galassia
LVD (400)LVD (400)Borexino (80)Borexino (80)Borexino Borexino (80)(80)
AmandaAmandaIceCubeIceCubeIceCubeIceCube
BOREXINO300 tons liquid scintillator in a nylon bag2200 photomultipliers2500 tons ultrapure waterEnergy threshold 0.25 MeVReal time neutrino (all flavours) detectorMeasure mono-energetic (0.86 MeV) 7Be neutrinoflux through the detection of ν-e.40 ev/d if SSM Sphere 13.7 m diam. supports
the P Ms & optical concentratorsSpace inside the sphere containspurified PCPurified water outside the sphere
Collab.:Italy, France, USA, Germany,
Hungary, Russia, BelgiumPoland, Canada
18 m diam., 16.9 mheight
Solar, atmospheric, reactor neutrino experiments
Emerging picture
µµee ττ
µµee ττ
µµ ττ
11SunSun
NormalNormal
22
33
AtmosphereAtmosphere
µµee ττ
µµee ττ
µµ ττ
11SunSun
InvertedInverted
22
33
AtmosphereAtmosphere
Tasks and Open QuestionsTasks and Open Questions
•• Precision for Precision for θθ12 12 andand θθ2323 •• How large is How large is θθ1313 ??•• CP-violating phase CP-violating phase ??•• Mass ordering Mass ordering ? ? (normal vs inverted) (normal vs inverted)•• Absolute masses Absolute masses ?? (hierarchical vs degenerate) (hierarchical vs degenerate)•• Dirac Dirac oror Majorana Majorana ??
•• Anything beyond Anything beyond ??
Gran Sasso 2nd generation neutrinoexperiments
Mass scale / Dirac or Maiorana?
(CUORE, GERDA)
Oscillation parameters (neutrino tau appearence, unitarityof the mixing matrix , matter effect)
(OPERA, ICARUS, Borexino)
How small θ13 ? ==> Improve limits (only if θ13 ≠0 and δ ≠0CP leptonic violation possible)
(OPERA)
Neutrinoless ββ Decay
76Ge
76Se
76As
O+
2–
2+
O+
Some nuclei decay onlySome nuclei decay onlyby the by the ββββ mode, e.g. mode, e.g.
Half life Half life ~ 10~ 102121 yr yr
MeasuredMeasuredquantityquantity
Best limitBest limitfrom from 7676GeGe
00νν mode, enabled mode, enabledbyby Majorana Majorana mass mass
Standard 2Standard 2νν mode mode
Neutrino masses and 0ν2β decayHeidelberg Moscow experiment
HV Klapdor et al, NIMA: Data Acquisition and Analysis of the 76-GeDouble Beta experiment in Gran Sasso 1990-2003
0.1< mν (0.4) <0.6 eV4 sigma
CUORE 400 kg cryogenic detector (now Cuoricino 42Kg) to search fordouble beta neutrinoless events using TeO2 crystals. Approved in 2004
The setup will probe the neutrinoless double beta decay of 76Ge crystalswith a sensitivity of T1/2 > 10-24 y at 90% confidence level, correspondingto a range of effective neutrino mass < 0.09 - 0.20 eV within 3 years.
Approved in 2005
ββ decay neutrinoless experiments
MIBETA (Milan)20 detectors of natural TeO2crystals130Te mass = 2.3 kg
CUORICINOSensitive 130Te mass = 40 kgStatus: running
CUOREproposal approved in 2004130Te mass = 400 kg
Heidelberg-Moscow11 kg of enriched 76Ge detect.The most sensitive experiment in the world76Ge -->76Se + 2e-
GENIUS-TFTest facility for GENIUS40 kg HM Ge
Approved: GERDASensitive mass: 1 ton enriched Ge crystals in Liquid N2
β decay n --> p + e- + ν
2β0ν is a very rare decay: T(half life) ≥ 10-25 years)
ν = ν
Majorana neutrino
Upper limit onthe mass of νe0,39 eV
CuoricinoThe CUORICINO set-up, 11 planesof 4 cristals 5x5x5 cm3 and 2 planeshaving 9 cristals 3x3x6 cm3 ofTeO2 .The total mass is 40 kilograms, oneorder of magnitude bigger thanother cryogenic detector The experiment is in data taking atGran Sasso
With Cuore neutrino masssensitivity < 10-2 eV(dependent from the model)
Now m < 0.4-2 eV
Cern Neutrinos to Gran Sasso (CNGS)
1979
Nobody has observed unambiguously the appearance of newflavours.
You can’t do it at the solar scale (E too small to produce muons)At the atmospheric scale oscillations are very likely
P(νµ → ντ) ≈ cos4 ϑ13 sin2 2ϑ23 sin2 [1.27 Δm223L(km)/E(GeV)]
Hence, you must be able to identify unambiguously τ leptons
CNGS has been designed for it
Over the next five years the present generation of oscillationexperiments at accelerators with long-baseline beams are expected to confirm the νµ ντ interpretation of the atmospheric ν deficit and to measure sin2 223 and |∆m2 23| within 10 ÷ 15 % of accuracy if |∆m2 23| > 10-3 eV2.
Neutrino facility P momentum (GeV/c) L (km) E (GeV ) p.o.t./year (1019)
KEK PS 12 250 1.5 2
FNAL NUMI 120 735 3 36
CERN CNGS 400 732 17.4 4.5
K2K and MINOS are looking for neutrino disappearance, bymeasuring the νµ survival probability as a function of theneutrino energy while OPERA will search for evidence of ντinteractions in a νµ beam.
CNGS schedule(schematic, simplified version)
“today”
18 August 2006
The 2 ways of detectingτ appearance @GRAN SASSO
νµ ….. ντ → τ- + X oscillation CC interaction
µ- ντ νµ ΒR 18 %h- ντ nπο 50 %e- ντ νe 18 %π+ π- π- ντ nπο 14%
OPERA: Observation of the decaytopology of τin photographic emulsion (~ µm granularity)
ICARUS: detailed TPC imagein liquid argon and kinematiccriteria (~ mm granularity)
Decay “kink”
ντ
ν
τ-
ν interaction
OPERA: an hybrid detector
8 cm
Emulsion analysis:VertexDecay kinke/gamma IDMultiple scattering,kinematics
Electronicdetector
→ finds thebrick of νinteraction→ µ ID,charge andp
Emulsions+lead + target tracker (scintillator strips)
Spectrometer(drift tubes-RPCs)
Pb Emulsion 1 mm
Basic “cell”
CNGS beam performances
50 ms10.5 µs 10.5 µs
LVD monitor of the CNGS beamNeutrinos from CNGS are observed through: the detection of muons produced in neutrino CC interactions
with the surrounding rock or in the detector the detection of the hadron jets produced in neutrino NC/CC
interactions in the detector
CNGS beam*νµ
µ
LVD
Gran Sasso rock
LVD monitor of the CNGS beam
From the Montecarlo simulation we expect 6.67 10-16 events/proton ontarget (p.o.t.)
1 year of data (200 days) -> 4.5 1019 p.o.t. -> 150 events/day
The neutrino candidate are defined as at least a signal from a counterof the detector with an energy deposit greater than 100 MeV.
We can discriminate CNGS event from cosmic muons requiring: horizontal direction of the reconstructed muon time coincidence of the event with the CNGS time spill (cosmicmuon background is then about 0.2 events/day)
The first CNGS event: OνE
Event Display: µ from rock
Event Display: internal ν NC/CC?
LVD rate
Agreement between the observed events and the expectedfrom the beam intensity!
18 8
, 11:
30
20 8
, 09:
12
21 8
, 07:
30
22 8
, 04:
17
Time event distribution
The LVD CNGS events timedistribution with respect tothe time spill agrees with theduration of the spill!
The analisys of data taking with the LVD detectorshows that:
the CNGS beam is working very well as it was expected
we continue to collect data and update the results
we want to make a deeper analisys of the data toextract more informations (external/internal, CC/NC)
OPERABeamevent
CC event originatedfrom material in front of thedetector (BOREXINO, rocks)
CC event in the first magnet
µ-track
(forgive about the red-line fit)
Angular distribution of all events
Polar angle
Azimuthal angle
Cosmic muons
Zoom on Beam events3.5° from below
Clean selected events
• The CNGS beam is operating smoothly with very goodquality• The tracking detectors of OPERA are taking data withpractically no dead time• More than 100 beam correlated events have beenobserved with a clean time distribution• The recorded events show the expected trackingperformances• OPERA is now ready for the next step: observingneutrino interactions in the Emulsion Cloud Chamber bricks
Next step : end of october run !!!
OPERA conclusions
Next step: from electronic detectors to emulsionanalysis
supermodule
8 m
TargetTrackersPb/Em.target
Emulsion analysis:
Vertex, decay kink e/γ ID, multiplescattering, kinematics
Extract selectedbrick
Pb/Em. brick
8 cm Pb 1 mm
Basic “cell”
Emulsion
Electronic detectors:
Brick finding muon ID, charge and p
Link to mu ID,Candidate event
Spectrometer
Binning ~ cm Binning ~ μm10-4
Brickproduction
CS box
Brick
Emulsion films
Lead boxes
BAM piling/pressing section
BAM wrapping section
Brick insertion, extraction,processing,
Brick Manipulating System
Emulsion developping lab
Vacuum sucker vehicle
Water Water CCerenkov erenkov (0.5-1 MT)(0.5-1 MT)•• Well known technique from Well known technique from Super-KSuper-K•• Interesting for Interesting for e/e/µµ separation separation
Tracking Calorimeters (100 KT) Tracking Calorimeters (100 KT)•• Fully active with liquid scintillator: ~Fully active with liquid scintillator: ~NOvANOvA•• Or sampling iron calorimeter: ~Or sampling iron calorimeter: ~MINOSMINOS•• Muon charge is crucial: B field !!!Muon charge is crucial: B field !!!•• Golden channelGolden channel
Hybrid emulsion (4 KT)Hybrid emulsion (4 KT)
•• Experience from Experience from OPERAOPERA•• Silver channelSilver channel Interesting to solveInteresting to solve
degeneracies degeneracies
•• Golden and bronze alsoGolden and bronze also
Detectors
Liquid Argon TPC (100 KT)Liquid Argon TPC (100 KT)
β-beamsuper-beam
CP asymmetryhas opposite sign
High energy beams only: High energy beams only: Nufact Nufact or highor high γ γ ββ-beam-beam
Low energy beam only:Low energy beam only:•• γ<γ<350350 ββ-beam-beam•• Super-beam Super-beam
Neu
trin
o E
nerg
yN
eutr
ino
Ene
rgy
BothBoth•• 3D active detector:3D active detector: Imaging, Imaging, calorimetrycalorimetry, , CCerenkoverenkov•• Challenging: ongoing R&D strategyChallenging: ongoing R&D strategy
And also:And also:•• Proton decayProton decay•• Supernovae neutrinosSupernovae neutrinos
ICARUSA self-triggering, high resolution, liquid argon calorimeter and tracker for studying
neutrino interactions and proton decay.
• T600 installation started in december 2004• The technical infrastructures in Hall B is in progress (electrical
power supply system, ventilation, cooling)• Call for tenders for the Nitrogen riliquefaction system launched• Data taking foreseen at the end of 2007
ICARUS T300 Detector’s performanceK
+[AB]! µ
+[BC]! e
+[CD]
Collection view
Run 939 Event 95
Induction 2 viewA
BC
DK+
µ+
e+A
A
B
B
C
C
µ+[AB]! e
+[BC]
AB
BC
K+
µ+
Run 939 Event 46
Particle identification by characteristic decay (µ+,µ-,K+,K-,Ko)
µ+
e+
µ+ e+
Main Physics Issues (“few kTon LAr detector”)
• proton and neutron decaysearches
• atmospheric neutrinos
• solar neutrinos
• cosmic neutrinos (SN, γ-raybursts, neutron starcollapse)
uud
e+
dd
pπ0
A new large European infrastructure for a detector 105-106 ton scale ?
Improved studies on proton decay, on low-energy neutrinos from astrophysical originand possible detection of future accelerator neutrino beams
Three detection techniques being studied: water-Cherenkov, liquid scintillator andliquid argon
Worldwide efforts
Laboratori Nazionali delGran Sasso, Italy
LNGS
Laboratoire Souterrainde Modane, France
LSM
Laboratorio Subterraneo de Canfranc, Spain
LSC
Institute of UndergroundScience, Boulby Mine, UK
IUS
Gerda
17000 visitors/year
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