SLIDE 1
Missing proton energy fake data effect on deltaCP
DUNE LBL meeting May 13 2019
Cristóvão Vilela
This is what we have presented before
- Mass-squared bias: ~0.04e-3 eV*eV
- sinsq(theta_23) bias: ~0.025
- deltaCP bias: ~ 0.3 pi
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Missing proton energy fake data effect on deltaCP DUNE LBL meeting - - PowerPoint PPT Presentation
Missing proton energy fake data effect on deltaCP DUNE LBL meeting - - PowerPoint PPT Presentation
Missing proton energy fake data effect on deltaCP DUNE LBL meeting May 13 2019 Cristvo Vilela This is what we have presented before Mass-squared bias: ~0.04e-3 eV*eV sinsq(theta_23) bias: ~0.025 deltaCP bias: ~ 0.3 pi 2
SLIDE 2
SLIDE 3
These are the spectra we have showed before
Background was not included on the nue samples (see next slide)
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SLIDE 4
This is what the backgrounds look like
Also, new selection and binning
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SLIDE 5
DeltaCP = 1.5 pi
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SLIDE 6
DeltaCP = 1.2 pi
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SLIDE 7
Fake data fit with latest analysis tools
Ignore error bars, look only at bias - these are just the gaussian-like uncertainties at the best-fit point
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SLIDE 8
Same, without backgrounds
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SLIDE 9
With th13 constrained
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SLIDE 10
Appearance only, th13 unconstrained
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SLIDE 11
All oscillation parameters fixed other than delta
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SLIDE 12
All oscillation parameters fixed other than delta and th13
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SLIDE 13
All oscillation parameters fixed other than delta and th23
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SLIDE 14
All oscillation parameters fixed other than delta and dmsq32
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SLIDE 15
15 years exposure all oscillation parameters fitted
7 years ND exposure
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SLIDE 16
7 years exposure all oscillation parameters, NuFit constraint on all except deltaCP
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SLIDE 17
Is this just a fluke?
- For a global energy scale transformation:
- From disappearance we get a biased mass-squared splitting:
○ Such that numu survival probability stays invariant ■ i.e., energy scale shift is absorbed by oscillation parameters
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SLIDE 18
Is this just a fluke?
- Ignoring the solar term, can write the
deltaCP dependence as:
- with
- Now apply energy scale transformation and
use transformed :
○
- Appearance probability is invariant under:
○ and
- To first order, deltaCP measurements are
robust wrt energy scale in a joint LBL fit.
○ Disappearance parameter measurements are not.
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SLIDE 19
So what about this?
arXiv:1507.08560
“Since the atmospheric parameters are fixed to their current best-fit values, and we are only interested in the δCP sensitivity,there is no need to include νμ and ̄ νμ disappearance channels in our analysis.”
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SLIDE 20
Delta CP energy scale robustness - neutrinos
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SLIDE 21
Delta CP energy scale robustness - antineutrinos
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SLIDE 22
Delta CP energy scale robustness - neutrinos
True atmospheric mass splitting known.
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SLIDE 23
Delta CP energy scale robustness - antineutrinos
True atmospheric mass splitting known.
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SLIDE 24
Degeneracies
Neutrinos
- Disappearance parameters can
be degenerate with deltaCP. Made with Luke’s plotting tool.
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SLIDE 25
Conclusions
- The missing proton fake data only induces a bias in delta CP if dmsq32 is
fixed at nominal.
○ Otherwise, there is a nearly perfect trade-off between biasing deltaCP and dmsq32 and the data prefer a biased dmsq32, which is not surprising given its significant effect in the disappearance samples.
- Our fake data biases dmsq32, not deltaCP
○ To make a case for deltaCP probably need fake data that’s (more) different from a global energy scale shift… ○ Need ideas on how to present this in the short term.
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