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New constraints on oscillation parameters from $ u_e$ appearance and $ u_mu$ disappearance in the NOvA experiment

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 نشر من قبل Gary Feldman
 تاريخ النشر 2018
  مجال البحث
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We present updated results from the NOvA experiment for $ u_murightarrow u_mu$ and $ u_murightarrow u_e$ oscillations from an exposure of $8.85times10^{20}$ protons on target, which represents an increase of 46% compared to our previous publication. The results utilize significant improvements in both the simulations and analysis of the data. A joint fit to the data for $ u_mu$ disappearance and $ u_e$ appearance gives the best fit point as normal mass hierarchy, $Delta m^2_{32} = 2.44times 10^{-3}{{rm eV}^2}/c^4$, $sin^2theta_{23} = 0.56$, and $delta_{CP} = 1.21pi$. The 68.3% confidence intervals in the normal mass hierarchy are $Delta m^2_{32} in [2.37,2.52]times 10^{-3}{{rm eV}^2}/c^4$, $sin^2theta_{23} in [0.43,0.51] cup [0.52,0.60]$, and $delta_{CP} in [0,0.12pi] cup [0.91pi,2pi]$. The inverted mass hierarchy is disfavored at the 95% confidence level for all choices of the other oscillation parameters.

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