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.

Virtual LER MAR13, 2007 (left) and wanted model (right)

ey ~ 2.0 Ey ~ 1.5

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

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

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

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

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

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

Symplecticity for XX vs. YY MIA data shows that the MIA

data for XX and YY seems to have similar quality

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

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

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

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

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

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

The Knob: magnet strength changes

QFP9R12 -0.645

QDP8R12 0.71

QFP7R12 -2.477

QDP6R12 -0.523

QFP5R12 -1.018

QDP4R12 1.15

QFP3R12 0.345

QDPR12 0.39

QFPR12 -2.033

QFP9R04 1.081

QDP8R04 0.434

QFP7R04 0.983

QDP6R04 0.325

QFP5R04 1.001

QDP4R04 -0.683

QFP3R04 0.865

QDPR04 -0.328

QFPR04 0.578

SKG1 -1.745

SKG2 3.494

SK6L -0.215

SK5L -0.013

SK4L 0.565

SK3L 0.561

SK2L -0.903

SK2 0.013

SK3 1.127

SK4 -1.194

SK5 0.418

SK6 0.416

SKG3 -1.357

SKG4 -1.579

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?