The Gran Sasso laboratory and the neutrino beam from … · The Gran Sasso laboratory and the...

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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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