Pheno 2014 Liveblog: Day Three Session 1

We start the final day with a session on neutrino physics.

8:45 am: Neutrino Oscillations: Present and Future, Chang Kee Jung

This looks like the review talk setting the stage for the audience.  Important reminder: neutrino physics has thrown up a number of results that were not theoretically expected (non-zero masses, large mixing angles, non-zero θ13).

2013 brought us 28 events at T2K and IceCube.  Former promises hope of probing CPV at neutrinos; latter a new age in neutrino astrophysics.

Outstanding question of θ23 still unresolved with T2K.  Looks increasingly like maximal mixing.  Similarly, fit to δCP prefers -π/2, also near-critical.  More broadly, we seem to have too much νμ disappearance and too much νe appearance.  Is this pointing to something new?

9:20 am: Neutrino Oscillations Theory and Phenomenology, Irina Mocioiu

We have reached a position in the last few years of a generally consistent picture, with a few anomalies.  Despite this, we still have basic questions about e.g. the mass hierarchy that we would like to resolve.

Even more fundamental than that, though, are questions about the nature of neutrinos and how they fit in the SM.  Neutrino masses demand either Majorana neutrinos, with phenomenology associated with that, or symmetries that forbid Majorana masses, and the consequences that implies.  Unfortunately, despite all we have learned since I was an undergrad, we still do not know for sure where to look.

This ultimately motivates and EFT approach to non-standard neutrino interactions.  This seems to be where this talk is going for what remains, though I haven't seen or heard 'effective field theory'.  The fact that neutrinos interact only weakly makes them more sensitive to these effects.  Strong constraints nonetheless exist from SU2L invariance and charged lepton phenomenology.

Important possible signal: monojets!  Gets in way of DM detection through this channel; also leads to further constraints.

These things can also be inconvenient for our attempts to measure the SM neutrino parameters, possibly to the extent of reconstructing the wrong regions of parameter space.

9:55 am: High Energy Astrophysical Neutrinos - Observations and Implications, Albrecht Karle

The PeV IceCube search.  Start with two events (Bert and Ernie), 2.8σ over backgrounds already.  Motivated focused search that found 28 total extending down to sub-100 TeV.  Additional year of data has found 8 further events, one at 2 PeV, still with no significant clustering in the sky.