Difference between revisions of "NOvA results"

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==Electron neutrino appearance results==
 
==Electron neutrino appearance results==
  
<math> 33 \nu_{e} </math> candidates were observed with a background of <math> 8.2 \pm 0.8 (syst.) </math>.
+
<math> 33 \ \nu_{e} </math> candidates were observed with a background of <math> 8.2 \pm 0.8 \ (syst.) </math>.
  
The hypothesis of inverted mass hierarchy with <math> \theta_{23} </math> in the lower octant is disfavored at greater than 93% C.L. for all values of <math> \delta_{CP} <\math>.
+
The hypothesis of inverted mass hierarchy with <math> \theta_{23} </math> in the lower octant is disfavored at greater than 93% C.L. for all values of <math> \delta_{CP} </math>.
  
  
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==Electron neutrino appearance results==
 
==Electron neutrino appearance results==
  
NOvA had observed  <math> 6 \ \nu_{e} </math>-like events in the FD, with a background prediction of <math> 0.99 \pm 0.11 (syst.) </math>
+
NOvA had observed  <math> 6 \ \nu_{e} </math>-like events in the FD, with a background prediction of <math> 0.99 \pm 0.11 \ (syst.) </math>
  
 
The range of <math> 0.1 \pi < \delta_{CP} < 0.5\pi </math> in the '''IH''' is disfavored at the 90% C.L. The range of <math> 0.25 \pi < \delta_{CP} < 0.95 \pi </math> in the '''NH''' is disfavored at the 90% C.L.
 
The range of <math> 0.1 \pi < \delta_{CP} < 0.5\pi </math> in the '''IH''' is disfavored at the 90% C.L. The range of <math> 0.25 \pi < \delta_{CP} < 0.95 \pi </math> in the '''NH''' is disfavored at the 90% C.L.

Latest revision as of 11:33, 3 November 2019

Analysis 2019

The best-fit parameters of neutrino oscillation for each choice of  \theta_{23} octant and hierarchy. The best-fit point is found for the normal hierarchy  \theta_{23} in the upper octant. In this case:

 \Delta m_{32}^2 = +2.48^{=0.11}_{-0.06} \times 10^{-3} eV^2/c^4

 sin^2 \theta_{23} = 0.56^{+0.04}_{-0.03}

 \delta_{CP} = 0.0^{+1.3}_{-0.4} \pi

Other results is showen by table:

  NO, LO IH, UO IH, LO
 \Delta m_{32}^2/ (10^{-3} eV^2/c^4)  +2.47  -2.54  -2.53
 sin^2 \theta_{23}  0.48  0.56  0.47
 \delta_{CP}/ \pi  1.9  1.5  1.4
   +1.6\sigma  +1.8\sigma  +2.0\sigma

Second Analysis

The results of the second analysis were published in 2017. This analysis used an exposure equivalent to  6.05 \times 10^{20} POT from the Fermilab NuMI beam.

Muon neutino disappearance results

The best fit in the normal hierarchy gives:

 \Delta m_{32}^2  = (2.67 \pm 0.11 ) \times 10^{-3} eV^2

 sin^2 \theta_{23} = 0.404^{+0.030}_{-0.022} \ (0.624^{+0.022}_{-0.030})

The best fit in the inverted hierarchy gives:

 \Delta m_{32}^2  = (-2.72 \pm 0.11 ) \times 10^{-3} eV^2

 sin^2 \theta_{23} = 0.398^{+0.030}_{-0.022} (0.618^{+0.022}_{-0.030})

Maximal mixing, where  sin^2 \theta_{23} = 0.5 , was disfavored at  2.6 \sigma.

Electron neutrino appearance results

 33 \ \nu_{e} candidates were observed with a background of  8.2 \pm 0.8 \ (syst.) .

The hypothesis of inverted mass hierarchy with  \theta_{23} in the lower octant is disfavored at greater than 93% C.L. for all values of  \delta_{CP} .


Sterile neutrinos?

First Analysis

The results of the first analysis were published in 2016. This analysis used a 14 kton-equivalent exposure of  2.74 \times 10^{20} POT from the Fermilab NuMI beam.

Muon-neutrino disappearance results

Assuming the normal hierarchy, the measurements have a next view:

 \Delta m^{2}_{32} = 2.52^{+0.20}_{-0.18} \times 10^{-3} eV^2

and  sin^2 \theta_{23} in the 68% CL range  [0.38, 0.65] , with two statistically degenerate best-fit values:

 sin^2 \theta_{23} = 0.43 \ (0.60)

Assuming the inverted hierarchy, the measurements have a next view:

 \Delta m^{2}_{32} = -2.56 \pm 0.19 \times 10^{-3} eV^2

and  sin^2 \theta_{23} in the 68% CL range  [0.37, 0.64] , with two statistically degenerate best-fit values:

 sin^2 \theta_{23} = 0.44 \ (0.59)


Electron neutrino appearance results

NOvA had observed  6 \ \nu_{e} -like events in the FD, with a background prediction of  0.99 \pm 0.11 \ (syst.)

The range of  0.1 \pi < \delta_{CP} < 0.5\pi in the IH is disfavored at the 90% C.L. The range of  0.25 \pi < \delta_{CP} < 0.95 \pi in the NH is disfavored at the 90% C.L.