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تسجيل مستخدم جديدPrecision constraints for three-flavor neutrino oscillations from the full MINOS+ and MINOS data set
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We report the final measurement of the neutrino oscillation parameters $Delta m^2_{32}$ and $sin^2theta_{23}$ using all data from the MINOS and MINOS+ experiments. These data were collected using a total exposure of $23.76 times 10^{20}$ protons on target producing $ u_{mu}$ and $overline{ u_mu}$ beams and 60.75 kt$cdot$yr exposure to atmospheric neutrinos. The measurement of the disappearance of $ u_{mu}$ and the appearance of $ u_e$ events between the Near and Far detectors yields $|Delta m^2_{32}|=2.40^{+0.08}_{-0.09}~(2.45^{+0.07}_{-0.08}) times 10^{-3}$ eV$^2$ and $sin^2theta_{23} = 0.43^{+0.20}_{-0.04} ~(0.42^{+0.07}_{-0.03})$ at 68% C.L. for Normal (Inverted) Hierarchy.
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The MINOS experiment ran from 2003 until 2012 and collected a data sample including 10.71x10^20 protons-on-target (POT) of beam neutrinos, 3.36x10^20 POT of beam antineutrinos and an atmospheric neutrino exposure of 37.88 kt-yrs. The final measuremen
t of the atmospheric neutrino oscillation parameters, dm^2_32 and theta_23, came from a full three flavour oscillation analysis of the combined CC nu_mu and CC anti-nu_mu beam and atmospheric samples and the CC nu_e and CC anti-nu_e appearance samples. This analysis yielded the most precise measurement of the atmospheric mass splitting dm^2_32 performed to date. The results are |dm^2_32|=[2.28 - 2.46]x10^-3 eV^2 (68%) and sin^{2}theta_23=0.35-0.65$ (90%) in the normal hierarchy, and |dm^2_32|=[2.32 - 2.53]x10^-3 eV^2 (68%) and sin^{2}theta_23=0.34-0.67 (90%) in the inverted hierarchy. The successor to MINOS in the NOvA era at FNAL, MINOS+, is now collecting data mostly in the 3-10 GeV region, and an analysis of nu_mu disappearance using the first 2.99x10^20 POT of data produced results very consistent with those from MINOS. Future data will further test the standard neutrino oscillation paradigm and allow for improved searches for exotic phenomena including sterile neutrinos, large extra dimensions and non-standard interactions.
The MINOS experiment took data for seven years between May 2005 and April 2012. Since then it has been reborn as the new MINOS+ experiment in the upgraded medium energy NuMI beam and started taking data in September 2013. An update to the MINOS stand
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