Particle Physics Seminar

Neutrino Oscillation is firmly established. The task ahead is to measure with increasing precision of the oscillation parameters, sin2223 and m223. The most sensitive determination of these parameters is conducted by measuring the disappearance of muon neutrino during 735km flight from the source, Near Detector at Fermilab, to the Far Detector at Soudan mine. Additional, sensitive search of sin2213 down to a few percent level is one of the goals of the MINOS program. Measurements and discoveries of the elements of neutrino mixing matrix outlined above critically depends upon the precision with which one can predict the neutrino flux ratio in the Far Detector with respect to the Near Detector. In the first half of my talk, I will describe the method of predicting the NuMI neutrino flux using the low-nu (hadronic energy) events in the Near Detector. The analysis provides an empirical parameterization of tuning the simulation of production spectra of secondary hadrons produced in the 120GeV proton-NuMI target collisions by fitting the spectra of muon neutrino charged-current events at low-nu. In the second half of my talk, I will present the latest MINOS result of electron neutrino appearance analysis based on a 7E20 protons-on-target exposure.