# Difference between revisions of "NOvA results"

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=[https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.123.151803 Analysis 2019]= | =[https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.123.151803 Analysis 2019]= | ||

− | + | This analysis became the first measurement of neutrino oscillation parameters using neutrinos and antineutrinos. | |

− | The best-fit point is found for the normal hierarchy <math> \theta_{23} </math> | + | |

+ | The best-fit point is found for the '''normal''' hierarchy and the '''upper''' <math> \theta_{23} </math> octant: | ||

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

Line 10: | Line 11: | ||

<math> \delta_{CP} = 0.0^{+1.3}_{-0.4} \pi </math> | <math> \delta_{CP} = 0.0^{+1.3}_{-0.4} \pi </math> | ||

− | + | The data prefer the '''normal''' hierarchy with a significance of <math> 1.9 \sigma </math> and the '''upper''' <math> \theta_{23} </math> octant with a significance of <math> 1.6 \sigma </math>. These results exclude <math> \delta_{CP} </math> values in the inverted mass hierarchy from <math> - 0.04 </math> to <math> 0.97\pi </math> in the lower <math> \theta_{23}</math> octant and <math> 0.04 </math> to <math> 0.91\pi </math> in the upper octant by more than <math> 3\sigma </math>. | |

+ | |||

+ | Other results: | ||

<table border="1" width="25%" cellpadding="5"> | <table border="1" width="25%" cellpadding="5"> |

## Latest revision as of 15:37, 28 May 2021

## Contents

# Analysis 2019

This analysis became the first measurement of neutrino oscillation parameters using neutrinos and antineutrinos.

The best-fit point is found for the **normal** hierarchy and the **upper** octant:

The data prefer the **normal** hierarchy with a significance of and the **upper** octant with a significance of . These results exclude values in the inverted mass hierarchy from to in the lower octant and to in the upper octant by more than .

Other results:

NO, LO | IH, UO | IH, LO | |
---|---|---|---|

# Analysis 2017

The results utilize significant improvements in both the simulations and analysis of the data. A joint fit to the data for disappearance and appearance gives the best-fit point as normal mass hierarchy,

,

,

.

The **68.3%** confidence intervals in the **normal** mass hierarchy are

,

,

.

The **inverted** mass hierarchy is **disfavored** at the **95%** confidence level for all
choices of the other oscillation parameters.

# Second Analysis (2016)

The results of the second analysis were published in 2017. This analysis used an exposure equivalent to from the Fermilab NuMI beam.

## Muon neutino disappearance results

The best fit in the **normal hierarchy** gives:

The best fit in the **inverted hierarchy** gives:

Maximal mixing, where , was disfavored at .

## Electron neutrino appearance results

candidates were observed with a background of .

The hypothesis of inverted mass hierarchy with in the lower octant is disfavored at greater than 93% C.L. for all values of .

## Sterile neutrinos

Sterile analysis used data collected from February 2014 to May 2016.

With an exposure of POT-equivalent, **95 NC-like events** were observe in the FD, compared with an expectation of . This result is consistent with three-flavor mixing within **1.03 σ**.
No evidence for depletion of NC events is observed in the FD at a distance of 810 km from the neutrino source and NOvA sees no evidence for active-sterile neutrino mixing.

NOvA set limits of and in a **3+1 model** scenario.

# First Analysis (2015)

The results of the first analysis were published in 2016. This analysis used a 14 kton-equivalent exposure of from the Fermilab NuMI beam.

## Muon-neutrino disappearance results

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

and in the 68% CL range , with two statistically degenerate best-fit values:

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

and in the 68% CL range , with two statistically degenerate best-fit values:

## Electron neutrino appearance results

NOvA had observed -like events in the FD, with a background prediction of

The range of in the **IH** is disfavored at the 90% C.L. The range of in the **NH** is disfavored at the 90% C.L.