Neutrino parameters with large experiments (CP violation, mass - - PowerPoint PPT Presentation
Mauro Mezzetto, Istituto Nazionale Fisica Nucleare, Padova Neutrino parameters with large experiments (CP violation, mass hierarchy,...) Present Status Different approaches for mass hierarchy Measuring CP: Dune and Hyper-Kamiokande
Mauro Mezzetto, Istituto Nazionale Fisica Nucleare, Padova
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Out of the 26 (please inform Wikipedia that aren’t 19) free parameters of the Standard Model, 4 are not yet measured: mνe, mνµ, mντ, δCP
mass ordering
neutrinos and antineutrinos
Neutrino mass ordering
atmospheric:
Leptonic CP violation
the CP violating phase in the PMNS mixing matrix
atmospheric:
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mass ordering would be an intringuing hint to build such extensions. Neutrino masses are the only laboratory check of cosmological parameters.
understand the matter-antimatter asymmetry in the Universe
(unitarity of the mixing matrix, NSI in neutrino oscillations, deviations from expected values of matter effects)
accelerator physics: proton decay, indirect DM searches, relic SN neutrinos etc.
The 3 ν model is matched by 4 anomalies conspiring to the same oscillation parameters LSND: a 3.5 σ excess of νe events in a neutrino beam created by pion decays at rest. First paper on
1995, the experiment has never been repeated.
MiniBoone: a 10 years effort at Fermilab to check the LSND result at different energies (but same
L/E), the final result had been inconclusive.
Reactor anomaly: recent recalculation of neutrino fluxes at reactors showed an enhancement of
about 3.5% of absolute fluxes with respect to previous calculations: all the reactor experiments at very short baselines could be reinterpreted as evidence of νe disappearance (about 2.5 σ). Recent results on reactor experiments seriously match the reliability of these recent calculations.
Source calibration of Gallex and SAGE: the source calibration of these experiments showed a
15% deficit of νe events. To be noted that the calibration had been designed and funded to check the efficiency of the detectors, while the sterile evidence is there assuming 100% efficiency of the detectors.
Overall fit: the 4 anomalies can accommodated in the same oscillation model by adding a 4th,
sterile, neutrino, with a mass of about 1 eV, nevertheless tensions exist in the global fit
Cosmology: severely constraints total number of neutrinos to 3 and their mass below 1 eV Most economical way to falsify steriles: a convincing null result from the source experiments at Borex (SOX) would falsify the sterile n interpretation of anomalies Most complete way to explore the phenomenology if steriles exist: the new short baseline project at Fermilab, with 3 liquid argon detectors, has the potential of fully exploit the several manifestations of sterile neutrinos.
disappearance: Juno
disappearance: INO, Hyper- Kamiokande
appearance: NOνA, Dune, Hyper-Kamiokande
in neutrino oscillations: Orca, Pingu
(Very) long baseline ν experiments have the best potential for this measurement, they set a time window for experiments with 3σ sensitivity
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Should be updated Orca and HK not included
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ORCA: arXiv:1601.07459; PINGU: arXiv:1401.2046
Resonant region: measure MH Saturated region: measure ∆m2
Dilution and systematics due to ν flux, cross-sections and angle smearing… but effect is large; Requires the identification of both νµ and νe (not cascade) events.
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Yanez, Kouchner: Adv.High Energy Phys. 2015 (2015) 271968 ORCA LoI PINGU LoI
ORCA: Installation time 3 years, ready in 2020 if funded in 2017 PINGU: Procurement and installation takes 4 years.
Performances are still preliminary
parameters and systematic errors could degrade performances (Capozzi et al, PhysRev.D.91.073011)
performances (Ribordy Smirnov, PhysRevD.87.11307)
computed
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CDR: arXiv:1508.07166, Physics: J.Phys. G43 (2016) no.3, 030401
2020)
measurement of sin2θ12, δm2
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and also SuperNovae, solar, atmospheric, geo neutrinos, proton decay, indirect DM searches ..
sin2θ12 δm2
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δm2
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As hard as to disentangle the two curves below Requires extreme control of detector response
MH sensitivity in 6 years. External measure of ∆m2
µµ could be crucial
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... because of a very favorable combination of parameters
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T2K (Phys.Rev. D88 (2013) 3, 032002) and NOνA (arXiv:1601.05022) measure a combination of θ13 and δCP while reactors (PDG 2012) measure pure θ13 effects. Their combination favours δCP =-π/2
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From T2K collaboration: PTEP 2015 (2015) 4, 043C01
Full statistics of the running experiments: T2K and Noνa, equal ν and ν runs, dashed lines: including systematics
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Upgrade the beam at 1.3 MW (already approved), collect 20 1021 pot (3 times nominal intensity) upgrade beam line, improve analysis
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Since a long time they are known to be the real bottleneck (or in positive the
Huber, MM, Schwetz, JHEP 0803 (2008) 021
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Varying θ13 at fixed luminosity Varying luminosity at fixed θ13 .
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A sophisticated close detector station: ND280 + Ingrid The best quality hadroproduction data ever produced (NA61) already included A huge, qualified, effort by the largest collaboration ever seen in neutrino physics At present limited by statistics
ν
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arXiv:1109.3262, arXiv:1412.4673, PTEP 2015 (2015) 053C02 Submitted to Science Council of Japan by T. Kajita on March 31, 2016 ... with a different configuration with respect to published papers
0.75 MW 1.3 MW Beam power
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Assuming 2Tank HD staging (2nd tank from 7th year), 10 years total run 78% (62%) coverage at 3σ (5σ) ~ 70 precision on δCP possible MH sensitivity Combining beam and atmospherics Same staging assumptions
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Proto Dune Double Phase Proto Dune Single Phase
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HK estimation assuming identical close detector as T2K Dune estimation extrapolating from Minos (no LAr close detector data so far)
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... under my own responsibility
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