1. LER MAR13 Analysis Is MIA data less accurate than that taken in last year? Is phase measurement still Ok? Is coupling measurement still Ok? Or simply that the MIA solution over-kill? Or MIA solution caused unwanted nonlinear effect? Yiton T. Yan SLAC Let us quickly survey some results and then we will discuss this at the end.

2. Virtual LER MAR13, 2007 (left) and wanted model (right) ey ~ 2.0Ey ~ 1.5

3. MIA wanted LER (left) and after-dialing LER (right)

4. Virtual LER MAR13, 2007 (left) vs. after dialing in MIA solution (right)

5. XX raw data ---- Mar13, 2007 (left) vs. April 25, 2006

6. YY raw data ---- Mar13, 2007 (left) vs. April 25, 2006

7. XY raw data ---- Mar13, 2007 (left) vs. April 25, 2006

8. YX raw data ---- Mar13, 2007 (left) vs. April 25, 2006

9. Symplecticity for XX vs. YY MIA data shows that the MIA data for XX and YY seems to have similar quality

10. Singular values ---- Mar13, 2007 (left) vs. August 15, 2006

11. Singular Vectors ---- Mar13, 2007 (left) vs. August 15, 2006

12. Comparison of R12 residuals: Apr 25, 2006 (top) vs. Mar 13, 2007 (bottom)

13. Comparison of R34 residuals: Apr 25, 2006 (top) vs. Mar 13, 2007 (bottom)

14. Comparison of R32 (y to x) residuals: Apr 25, 2006 (top) vs. Mar 13, 2007 (bottom)

15. Comparison of R14 (x to y) residuals: Apr 25, 2006 (top) vs. Mar 13, 2007 (bottom)

16. The Knob: magnet strength changes QFP9R12-0.645 QDP8R120.71 QFP7R12-2.477 QDP6R12-0.523 QFP5R12-1.018 QDP4R121.15 QFP3R120.345 QDPR120.39 QFPR12-2.033 QFP9R041.081 QDP8R040.434 QFP7R040.983 QDP6R040.325 QFP5R041.001 QDP4R04-0.683 QFP3R040.865 QDPR04-0.328 QFPR040.578 SKG1-1.745 SKG23.494 SK6L-0.215 SK5L-0.013 SK4L0.565 SK3L0.561 SK2L-0.903 SK20.013 SK31.127 SK4-1.194 SK50.418 SK60.416 SKG3-1.357 SKG4-1.579

17. Discussion – Why MIA LER solution did not work on Mar 13, 2007, what should we do next for LER? Simply LER MIA data was not good enough to warrant a good enough virtual LER? The solution over-kill: strong changes of global skew, etc. causing significant orbit change which was not restored to the original orbit after dialing in MIA solution? Others? What should we do next for LER?