Minutes from March 4 Meeting


Mayda Velasco gave a talk about the NUMI on and off-axis beams, considering the differences between positive and negative horn polarity (i.e. making a mostly neutrino or a mostly antineutrino beam). Bottom lines for a NUMI off-axis beam, when horns and target are in nominal configuration: http://lotus.phys.nwu.edu/~mvelasco/nu_bar/off_axis.ps


Andre DeGouvea gave a talk about the sensitivity to matter effects, Ue3^2, and CP violation, using the fluxes assumed above. Where relevant Andre, Gabriela and Mayda assumed there would be both an on-axis and an off axis measurement.
The running assumptions are: off and on axis detector 40kton-years for neutrino running, and 80 kton-years for antineutrino running. The efficiency and background assumptions correspond to segmented minos off-axis (so very little NC background), and minos on-axis (more NC background). The assumption is that the two detectors have the same mass, so given that MINOS is 5kton, if you had an off-axis detector at 5kton and a proton driver upgrade (to gain a factor of 4) then you would be running for 2 years neutrino mode, 4 years antineutrino mode. If you had the off axis detector with more mass, that counts for more since most of the statistical power for looking at numu to nue comes from the off-axis beam.
Plots were shown for three different values of solar mass splitting (dm_12^2), since for these three regions the physics reach is different. Steve Geer made the suggestion that for given values of ue3^2, one should also include the measurement that could be made by JHF to SuperK--as a constraint--the different energy could be an important constraint in some (if not most) of the above plots.
Deborah Harris
Last modified: Mon Mar 4 15:39:45 CST 2002