PPEG plan for development of physics case for RDR IDS-NF plenary
meeting October 19-21, 2011 Arlington, VA, USA Walter Winter
Universitt Wrzburg TexPoint fonts used in EMF: AAAAA A A A 2
Contents The setting and consequences: the big three physics topics
2011: T2K hint for nonzero 13 Evidence for sterile neutrinos?
Superluminal neutrinos at OPERA? Other activity: PINGU Summary
[apologize for not citing all talks of our WG, but not directly a
summary talk ] T2K hint for nonzero 13 4 T2K hint for non-zero 13 ?
Source: T2K June 15, 2011: Indication of Electron Neutrino
Appearance from an Accelerator-produced off-axis Muon Neutrino Beam
2.5 exclusion of 13 =0 5 Consequences of T2K hint Parameter space
for CP starts to become constrained; CP violation difficult (need
to exclude CP =0 and ) Need new facility! Huber, Lindner, Schwetz,
Winter, 2009 6 When will T2K be confirmed? Example: Double Chooz If
T2K best-fit confirmed, data already on tape? Expect significant
results in 2012! (M. Lindner, TAUP 2011) 7 Impact on Neutrino
Factory? Staging: built low-luminosity (1/25) option first?
Optimization of accelerator, given existing equipment? Costing???
(P. Huber) 8 Impact on theory? Non-zero 13 degree to which -
-symmetry is broken? Tri-bimaximal mixings perhaps no attractive
starting point anymore? Challenges: 13 and 12 deviations from TBM
values! Some flavor symmetries (A 4 etc) disfavored? Quark-lepton
connections? GUTs? Non-zero 13 ~ Anarchy? Or: Anarchy + some
structure Froggatt-Nielsen? (R. Mohapatra vs. H. Murayama) 9 Plans
and consequences Plans: Study of optimization and systematics for
large 13 Impact of prior knowledge of 13 ? Precision physics case
for NuFact? Quantification of staging scenarios Follow model
building for large 13 Interesting quantities/relationships? Clues
for required precision? Consequences: Establish physics case for
NuFact compared to alternatives; luminosity-staging? Muon collider
program: what do they need/want [physics, accelerator]? No decision
on final RDR strategy before 13 hint confirmed/established!? Then
maybe even RDR = LOI? Evidence for sterile neutrinos? 11 Evidence
for sterile neutrinos? LSND/MiniBooNE antineutrinos Reactor anomaly
Global fits (arXiv: ) (B. Fleming, TAUP 2011) (Kopp, Maltoni,
Schwetz, ) 12 Arbitrary sterile s Cosmology: upper bound O(1 eV)
However: sterile neutrinos even preferred, if light enough Cannot
exclude that light sterile neutrinos hide among the actives (Hamann
et al, Phys.Rev.Lett. 105 (2010) ) m1m1 m2m2 m3m3 m 4 ? 13
Generalized exclusion limits without any constraints on m 41 2
(Meloni, Tang, Winter, arXiv: ) From e disppearance From
disppearance From LBL- disppearance (higher order effect) 90% CL, 2
d.o.f. Precision physics case for NuFact in presence of sterile
neutrinos? 14 Sterile s: Consequences VLENF Physics and
optimization? Can VLENF and LL-LENF be the same thing? How would
that look like? Evidence on very light steriles? Would help the
precision physics case Need to be followed further Superluminal
neutrinos at OPERA? 16 OPERA superluminal neutrinos? Time of flight
measurement of muon neutrinos Comparison of proton waveform with
neutrino events Advanced wrt speed of light by t=60.7 ns (6 ),
which cannot be accounted for otherwise (out of the ns) (OPERA,
arXiv: ; submitted Sept. 22, 2011) 17 Convincing theories? Have to
take into account SN 1987A observations; confirm MINOS results
Either strong energy-dependence of effects, or flavor dependence
Violation of Lorentz invariance implied? However, so far no
convincing theory (too pre-mature) No of papers discussing OPERA
results: 93 up to date (average: 3.4 per day) Need to follow this
development 18 Some comments on possible explanations Common
prejudice: rising and falling edges relevant for statistical
significance of effect However: Any description leading to
deviations from proton waveform shape affects g.o.f. Examples:
Smearing from proton to neutrino waveform Shortcuts of steriles
through extra dimension (Dotted: 200ns Gaussian filter, arXiv: ) 19
OPERA: Consequences HENF can test this phenomena, in principle;
compared to alternatives (right energies, right channels); but:
bunches? Important for physics case of NuFact, if confirmed Higher
precision through more statistics, longer baseline,
neutrino-antineutrino, ? 2 x BCT M. Dracos, J. Diaz New ideas/other
activities 21 Other activity: PINGU (Phased IceCube Next Generation
Upgrade) Decrease spacing of IceCube DOMs at South Pole huge mass
already at 1 GeV Supernova neutrinos? Proton decay? Atmospheric
neutrinos? Beams? (V eff from J. Koskinen, PINGU phase I only,
preliminary; Tang, Winter, to appear) FNAL/CERN-IceCube 22 NF beam
to PINGU? Key issue: energy resolution (non- magnetized detector);
need 10-20% E (see Huber, Schwetz, arXiv: ) Applications: (Tang,
Winter, to appear) Replace magic baseline (small 13 )
Single-baseline LENF (large 13 ) (avoid tau contamination by low E
, which is a serious issue for a non-magnetized detector!) 23
Summary and conclusions Need to follow and interpret developments
of big three discoveries this year: Large 13 Sterile neutrinos
Superluminal motion of neutrinos Large 13 requires Systematics
study Precision physics case? Definition of setup comparable to
LBNE? Staging? LL-LENF? BACKUP 25 OPERA: Model constraints Fraction
of superluminal neutrinosGaussian smearing (arXiv: )
