1. 1 Recent developments on sensitivity calculations Effect of combined le and me running –Is there a statistical advantage over pure le running? Discrimination between ‘standard’ oscillations and decay –Can we confuse oscillations for decay and vice versa? Effect of beam systematics on  m 2 resolution –Replace bin-to-bin uncertainties with more realistic estimates D. A. Petyt 26 th March 2003

2. 2 Combined run with le and me, spectra and ratios Improved measurement of the dipImproved measurement of the he tail

3. 3 Combined run with le and me, spectra and ratios

4. 4

5. 5

6. 6 Parameter measurement errors It was suggested at SC that combined le and me running may improve the measurement of oscillation parameters over pure le running This does not appear to be the case in this analysis for values of  m 2 in the SK allowed range This study uses the same (2% norm + 2% bin-to- bin) systematic errors for both le and me. Conculsions may change when more realistic errors are applied.

7. 7 Oscillations vs decay One of the goals of the CC energy analysis is to discriminate between ‘standard’ and ‘non-standard’ oscillation models by fitting the shape of the CC energy spectrum. Neutrino decay is one of these competing models: Standard osc: Neutrino decay: Discrimination between osc and decay was first studied in NuMI-L-701. Here I ask the following questions: –If the truth is oscillations, can we fit with the decay hypothesis? –If the truth is decay, can we fit with the oscillation hypothesis? –Do runs with Ph2le and Ph2me give further discrimination?

8. 8 Data sample: decay, fit hypothesis: decay Additional discrimination from NC rate – decay model predicts a deficit of NC events due to   s oscillations. Not considered here. Contours at 90,99% C.L.

9. 9 Data sample: oscillations, fit hypothesis: decay Fit is OK at high energy but poor below 4 GeV    Contours at 90,99% C.L.

10. 10 Data sample: decay, fit hypothesis: oscillations    Fit is poor at low and high energy, OK around peak, bad   Contours at 90,99% C.L.

11. 11 Data sample: decay, fit hypothesis: oscillations    Short run with Ph2me produces a significant shift in the allowed region – a clear indication that something is wrong… Ph2me, 2.5e20 p.o.t. Contours at 90,99% C.L.

12. 12 Beam systematics The CC analysis incorporates the following beam systematics: –2% (correlated) overall normalisation error –2% (uncorrelated, 1 GeV bins) bin-to-bin error In what follows, I have replaced the bin-to-bin error with modern estimates of the far/near spectrum ratio uncertainties, with and without MIPP (see M. Messier talk at SC) I’m not sure what the uncertainty on the overall normalisation should be – I’ve tried running with different values to assess the sensitivity to this error and have also tried shape-only fits. The results that I have obtained are somewhat surprising and so should be viewed as very preliminary. However, I have stared at the code for some time and have not found anything wrong, yet…

13. 13 Error on the F/N ratio, from M.Messier talk at SC Uncertainties are quite small in the ‘oscillation’ region. Note statistical error in the 3-4 GeV bin (peak of Ph2le distribution) is ~5% for 7.4e20 p.o.t.

14. 14 Effect of normalisation error on  m 2 resolution    is minimised w.r.t. sin 2 2 

15. 15 Norm. and shape-only fits I use shape-only fits from now on to study the effect of bin-to-bin uncertainties

16. 16 Effect of bin-to-bin errors on shape-only fits Effect is surprisingly small (note 18.5e20 p.o.t. exposure) Note asymmetric errors on  m 2

17. 17 Effect appears most pronounced for low  m 2

18. 18

19. 19 syst. errors mipp errors

20. 20 Comparison with NuMI-L-701 analysis Inner curve: hose on, outer: hose off Left-hand plot shows broadly similar features to my analysis Right-hand plot looks somewhat different to what I observe.  m 2 resolution seems much worse than I obtain. Increased statistics of ‘hose on’ beam may account for some of the improvements seen here. Need to understand how these plots were produced.