1. booster corrector measurement QA Phil Schlabach 1 May 2007 Proton Source Magnet Meeting

2. booster corrector measurement QA online QA –protect against bad measurements which are not discovered until later –protect against bad magnets let’s assume for the moment there is an “offline” QA –provide feedback during production measurements to “measurer” “analyst”

3. measurement plan AC measurements with fixed coil array –excite each element individually with the specified profile other elements are connected to the PS, current set to 0 –excite all elements

4. booster corrector measurement QA 1.strength 2.harmonics 3.coupling quality of the measurement –1, 2 quality of the magnet –1, 3

5. strength measurement tolerances compute a strength “error function”  =current_mon*TF_nom-measured_field apply tolerance band

6. harmonics tolerances monitor the field shape @y=0, By(x) probes B n, Bx(x), A n monitor min/max B y (x), B x (x), |x|<1.5” apply tolerance band

7. other centering, angles –see slides single vs. multi-element excitation –also slides should we monitor coil voltages, currents (or something) –coupling, regulation issues?

8. centering, angles so far, we have been looking at harmonics re-analyzed based the normal quadrupole center –this is difficult to do online as it links information between “separate” measurements –there are similar issues with the way we’ve done angles for certain cases this is better done offline

9. centering, angles (2) proposal: for online analysis leading to QA evaluation, analyze each measurement independently –centering, angle –monitor offsets angles relative to expected angles both should be small deviations will reveal both setup and/or coupling issues

10. centering, angles (3) e.g. –probe offset or rotated will need some experience to know what to expect mm for offset, few deg. for rotation? –coupling excitation of normal element  skew –shows up in the angle excitation of (e.g.) sextupole  dipole –shows up in the centering offsets monitor in the same manner as strength error, field shape –plot x0, y0, , apply tolerances for any of this to be useful we will have to figure out how to deal with the field of the earth

11. single vs. multi-element excitation remarks so far deal with single element excitations multi-element excitations –one would have to choose an element for the online analysis (e.g. analyze as “normal quad” by fiat) –then try to devise a monitoring scheme –that’s as far as I’ve thought it out

12. list of variables strength errorstrength-TF nom *I field defectmax/min of B y (x), B x (x) inteval of  1.5” centering offsetsfield center for each element (except dipole) angular offsetfield angle - nominal

13. post testing reanalysis, 2 nd pass at magnet quality, and posting to repository trend analysis