3rd oscillations working group report: i t just got interesting

Kurt Woschnagg*UC Berkeley

*WG co-lead with Ty DeYoung

IceCube collaboration meeting, Banff, March 8, 2014

3rd Oscillations Working Group Report:It just got interesting

Atmospheric Neutrino Oscillations

Search for muon neutrino disappearance in DeepCore data

Atmospheric Neutrino Oscillations

Search for muon neutrino disappearance in DeepCore data

Theoretical oscillogram

Observables

Likelihood scan inparameter space

Current νμ disappearance results

Other analyses, including ντ appearance, in event selection stage→ Low-Energy Summary by Jason K.

IC79 νμ disappearance: final level expectationsEvent rates (normalized to burn sample)

35% energy errordown to ~15 GeVusing Monopod

~7000 events in full sample

~80% neutrino purity

needs to be understood

Laura Gladstone (UW)

Confidence contours with Multillh

Confidence contours with Multillh

IC79 νμ disappearance: data challengeLaura Gladstone (UW)

IC86 νμ disappearance: multiyear extensionJuan Pablo Yáñez (DESY)Results from IC86-I analysis:

IC86 νμ disappearance: multiyear extensionJuan Pablo Yáñez (DESY)Extension to three years:

(LE summary has details)

IC86 νμ disappearance: new energy estimatorUse combinedReco by Andrii Terliuk

IC86 νμ disappearance: new energy estimator

IC86 νμ disappearance: new energy estimator

IC86 νμ disappearance: background templateNeed background template for likelihood fit

Relaxed veto cuts to estimate background from CORSIKA

New approach: estimate background from data

IC86 νμ disappearance: background template

IC86 νμ disappearance: background template

IC86 νμ disappearance: gains in statisticsTake three years instead of one: +200%Remove faulty selection logic: +40%

Remove RTVeto cut: +20%

Total increase: 1500 events to 7500 events

And it all adds up to…Sensitivity for three years of IC86 data

Now we’re talking!

Upgoing νμ survival probability

Vacuum only

3 Fl

avor

s

Including Matter

3 Fl

avor

s

4 Fl

avor

s

Vacuum only

4 Fl

avor

s Including Matter

Standard 3-flavor oscillations

With a sterile neutrino

IC59 sterile neutrino search (from Friday plenary)

Marius Wallraff, Christopher Wiebusch (Aachen)

Warning, the fit is 2-d Shown are projections

Ratio: Experiment and Best Fit relative to Null Pulls: Experiment and Best Fit relative to Null

IC59 diffuse HE sample(A. Schukraft)

IC59 sterile neutrino search (from Friday plenary)

Marius Wallraff, Christopher Wiebusch (Aachen)Significances calculated from log L = log L(Best fit) – log L(null) (assuming 2 dof)

m422 = 0.156 eV2

q24 = 17°

IC79+IC86 sterile neutrino searchCarlos Argüelles Delgado, Jordi Salvadó Serra (Madison)

IC79+IC86 diffuse HE samples (C. Weaver)Higher energy range than IC59 sampleDifferent theoretical approach to calculating oscillation probabilitiesAs in IC59 analysis, action is in zenith angle:

Caution: We have had a zenith dip at -0.4 due to a bug (“the NiuGen bug”) before

IC86 sensitivity (one year)

Disfavored by cosmological data

Burn sample fits

IC79

IC86

IC59

IC79+IC86 sterile neutrino search: outlook

+ Explain things like this:

IC86 IC59

1. IceCube is competitive with dedicated oscillation experiments

2. Marius may not graduate for a while…

3. We will have frequent oscillation calls

Conclusions