Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://nuclphys.sinp.msu.ru/conf/epp10/Brunner.pdf Äàòà èçìåíåíèÿ: Sat Sep 7 16:20:14 2013 Äàòà èíäåêñèðîâàíèÿ: Fri Feb 28 02:28:50 2014 Êîäèðîâêà:

NEUTRINO TELESCOPES AS TARGETS FOR LONG-BASELINE NEUTRINO BEAMS

J. Brunner CPPM (Marseille)




Layout
· Neutrino Telescopes
·(

talk Ch.Spiering, Saturday)

·

Antares, IceCube/DeepCore

· Neutrino Oscillations · Results from Antares · Results from IceCube/Deep-Core · Matter effects & Neutrino Mass hierarchy · PINGU : Low energy extension of IceCube · ORCA : Low energy option of KM3Net · Neutrino Beams · Muon Event Counting · Electron Event Counting


IceCube

~220 /day Threshold IceCube ~ 100 GeV DeepCore ~10 GeV


Deep-Core
·

More densily instrumented than IceCube · 8 special strings + 7 nearest standard strings · Spacing 45 -72 m
· (IceCube 125 m)

· ·

Vertical Spacing 7m
· (IceCube 20m)

Clearest ice (eff ~ 45-50 m) · High QE PMT (35%)


Deep-Core
·

More densily instrumented than IceCube · 8 special strings + 7 nearest standard strings · Spacing 45 -72 m
· (IceCube 125 m)

· ·

Vertical Spacing 7m
· (IceCube 20m)

Clearest ice (eff ~ 45-50 m) · High QE PMT (35%)


Antares
·

· · · · ·

Mediterranean Sea close to Toulon Depth ~2475 km Volume ~0.01 km¨ 12 strings, each with 25 PMT triplets Operating in final configuration since 2008


Oscillations of atmospheric neutrinos
Muon neutrino survival probability Vertically upward
Mena et al. PR D78 2008
ANT ARE S/De epCo re
cosmic ray

Earth L



Horizontal

Ch. Spiering


IceCube/Deep-Core results
IC79 :May 2010-April 2011 319 days lifetime Neutrino events: 719 DeepCore 38000 high energy Zenith angle only analysis
arXiv:1305.3909

IC86 :May 2011-April 2012 343 days lifetime 1487 neutrino events Strict selection : "direct light"
ICRC 2013 : Contribution 450


Summary of Results
ICRC 2013 : Contribution 848

·

Clear signal of atmospheric neutrino oscillations seen in IceCube and Antares

IceCube/DeepCore : - One year of data analysed - Strong potential for future studies
·


Deep-Core 6 years (2017)
Current results statistics limited · Shown extrapolation assumes additional improvements 1)Higher efficiency 2)Better resolutions 3)Smaller systematics uncertainties
·
ICRC 2013 : Contribution 460


Matter effects & Mass Hierarchy
· · ·

Solar Neutrinos : Matter effects inside sun
·

m2 > m1 m3 >< m1,m2

Matter effects in Earth (not yet measured !)
·

Normal Hierarchy

Inverted Hierarchy


Example Earth Matter Effect : P(

µ

µ)
NH IH

Resonance energy Earth mantle : 6-7 GeV
GLOBES

cos = 0.6 Baseline = 7645 km Inclination = 36.9°


PINGU Design
· · · · ·

Precision IceCube Next Generation Upgrade 20-40 Additional Strings inside Deep-Core Volume Strings ~300m high, 60-120 Optical Modules Instrumented Volume 3-4 Mtons Energy threshold ~2 GeV


KM3Net project


KM3Net project


KM3Net ­ ORCA Layout
Oscillation Research with Cosmics in the Abyss


PINGU ­ ORCA : Energy
Energy reconstruction from total light yield · Ice is a better calorimeter due to scattering
· ·

Energy reconstruction from fitted track length

ORCA PINGU

ICRC 2013 : Contribution 555

ICRC 2013 : Contribution 164


PINGU ­ ORCA : Zenith angle
Resolution close to kinematical limit · Water is a better tracker due to absence of scattering
·

PINGU

ORCA

ICRC 2013 : Contribution 555

ICRC 2013 : Contribution 164


Sensitivity Calculation
Fit of event count in Energy-Zenith space · Color code : bin-by-bin significance of hierarchy difference
·
Oscillation parameter fixed Oscillation parameter fitted

W. Winter : arXiv:1305.5539


PINGU Oscillation parameters

Side effect of correlation between mass hierarchy and oscillation parameters · After one year of data taking with PINGU competitive measurement of dm232
·

ICRC 2013 : Contribution 555


Sensitivity Calculation
3 years PINGU (20 lines) · 1.3-2.9 sigma separation of mass hierarchy hypothesis
·

Challenges of measurements with atmospheric neutrinos: · Cancellations !
·
· neutrinos / antineutrinos · muons / electrons (flavour ID) · Energy resolution · Oscillation parameters

W. Winter : arXiv:1305.5539


Neutrinos from Beams
Eliminate ambiguities · Improve mass hierarchy sensitivity
·

arXiv:1301.4577

Narrow band beam 6-9 GeV 1020 p.o.t.


P(

µ

µ)
GLOBES

cos = 0.1 Baseline = 1274 km Inclination = 5.7°

NH IH


P(

µ

µ)
GLOBES

cos = 0.2 Baseline = 2548 km Inclination = 11.5°

NH IH


P(

µ

µ)
GLOBES

cos = 0.3 Baseline = 3823 km Inclination = 17.4°

NH IH


P(

µ

µ)
GLOBES

cos = 0.4 Baseline = 5097 km Inclination = 23.6°

NH IH


P(

µ

µ)
GLOBES

cos = 0.5 Baseline = 6371 km Inclination = 30.0°

NH IH


P(

µ

µ)
GLOBES

cos = 0.6 Baseline = 7645 km Inclination = 36.9°

NH IH


P(

µ

µ)
GLOBES

cos = 0.7 Baseline = 8919 km Inclination = 44.4°

NH IH


P(

µ

µ)
GLOBES

cos = 0.8 Baseline = 10194 km Inclination = 53.1°

NH IH


P(

µ

µ)
GLOBES Beam to IceCube

cos = 0.9 Baseline = 11468 km Inclination = 64.2°

NH IH


P(

µ

µ)
GLOBES

cos = 1.0 Baseline = 12742 km Inclination = 90.0°

NH IH


Counting Muons from Beam Neutrinos
·

Optimal Beamline : 7000-8000 km

·

Favoured Option:
Mton underwater detector (ORCA)

arXiv:1301.4577

· FermiLab ­ KM3Net site in Mediterranean Sea · 1300 versus 950 events for both mass hierarchy hypotheses in

·

Inverse approach : Counting "Electrons"


P(

µ

e)
GLOBES (CP-phase varied in steps of 30°)

cos = 0.1 Baseline = 1274 km Inclination = 5.7°

NH IH


P(

µ

e)
GLOBES

cos = 0.2 Baseline = 2548 km Inclination = 11.5°

NH IH


P(

µ

e)
GLOBES

cos = 0.3 Baseline = 3823 km Inclination = 17.4°

NH IH


P(

µ

e)
GLOBES

cos = 0.4 Baseline = 5097 km Inclination = 23.6°

NH IH


P(

µ

e)
GLOBES

cos = 0.5 Baseline = 6371 km Inclination = 30.0°

NH IH


P(

µ

e)
GLOBES

cos = 0.6 Baseline = 7645 km Inclination = 36.9°

NH IH


P(

µ

e)
GLOBES

cos = 0.7 Baseline = 8919 km Inclination = 44.4°

NH IH


P(

µ

e)
GLOBES

cos = 0.8 Baseline = 10194 km Inclination = 53.1°

NH IH


P(

µ

e)
GLOBES Beam to IceCube

cos = 0.9 Baseline = 11468 km Inclination = 64.2°

NH IH


P(

µ

e)
GLOBES

cos = 1.0 Baseline = 12742 km Inclination = 90.0°

NH IH


Optimal Baseline ?
For L>2000km the oscillation probabilities are always well separated for both MH hypotheses · To find optimal baseline calculate event rates
·
· N ~ 1/L2 · N ~ E (cross section) · Fixed beam profile · ORCA detector response

NH IH


Optimal Baseline
·

L=2600km maximizes the difference in event rates between two MH hypotheses

Event rate difference NH - IH


Proton Accelerator Complex Protvino

Presentation S. Ivanov (IHEP) on 22/11/2012 @ CERN

Talk Wednesday


Protvino ­ ANTARES (ORCA)
Baseline 2588km ; beam inclination : 11.7° (cos = 0.2) · Deepest point 134km : 3.3 g/cm3
·


SKAT bubble chamber
p target focus Decay pipe 140m 270m 245m Shielding 55m SKAT

Courtesy: R. Nahnhauer


Beam parametrisation (1988)
· Very clean µ beam · Less than 1% contaminations from other flavours · Most neutrinos between 18 GeV
Z. Phys. C 40 (1988) 487


Event rates - Signal
Event numbers for 1.5 1021 p.o.t.s · 20 statistical separation of both Mass Hierarchy hypotheses from signal · 10000 muon events for beam normalisation
·
· 3.5% separation between MH hypotheses

· Other contributions: : 1316 +/- 13 ; 1416 +/- 8 ; NC : 4732

NH 10927 +/ 24 IH 10548 +/ 43

NH 1621 +/ 255

µ CC

e CC
IH 497 +/ 100


Flavour identification
· Misidentification probability : · assume same for both directions
· 50% at 2 GeV

random ; 20% at 5 GeV ; 10% at GeV


Event rates ­ All Flavours & Mis-ID
· · · · ·

Event numbers for 1.5 1021 pots 9-18% difference for NH/IH 7 statistical separation of MH hypotheses Can allow for few % syst. Uncertainty No requirement of energy reconstruction

tracks

NH 10690 +/ 45 IH 10244 +/ 15

cascades
NH 7300 +/ 200 IH 6420 +/ 80


Synergies between potential Sites
Protvino

4.1°

11.0° 13.6°

Modane 2393km Antares 2588km

Gran Sasso 2189km Nemo 2574km


Conclusion
· · · · · ·

Upgraded proton accelerator at Protvino well suited for LBL towards Mediterranean Sea Needed : 1021 p.o.t. within few years Preliminary Performance Figures of ORCA encouraging Synergy with Underground Labs in the same beam Complementary to measurement with atmospheric High Significance determination of Mass Hierarchy


Backup


Oscillation parameters
Taken from Global Fit (Fogli et al.) for both hierarchy options · CP phase left free
·


Oscillation Probabilities

· All relevant oscillation probabilities taken into account · Full 3flavour treatment · CPphase variations included


Neutrino Cross sections
Simple parton scaling assumed (QE, Res. ignored) Flavour universality m threshold

NC approximation


Neutrino Cross sections
Simple parton scaling assumed (QE, Res. ignored) Flavour universality m threshold

NC approximation

NC, CC: e µ



Solid : neutrino , dashed : antineutrino


Event rates
Here : no flavour misidentification · CC Rates
·

·

NC Rates


Event rates
Include Background and Flavour tagging · Total Background :
·

·

Total Event Rate :