1. CC background systematics or “Once more, this time with errors” Philip Rodrigues Oxford Group Meeting 6/11/07

2. 2 Error error MC stats similar to data stats – need to add in MC error to c 2 : Changes best fit point, because where S CC and S NC are what we’re trying to find

3. 3 Calculating parameter errors Use mean of up/down errors ( Dc 2 = 1 ) as symmetrical error in plots TH2::SetContour(50)

4. 4 Result – no shower scale Flatter More consistent errors Same NC dip

5. 5 Shower scale No evidence for significant shower scale Cutoff in fit at 1.8

6. 6 Robustness 1 Still not very robust

7. 7 Robustness 2 Still, not too bad considering: –RO pid has smaller lever arm

8. 8 Conclusions Results look more convincing with correct errors Robustness problems remain