Beams Division Seminar Configuration Management in the Tevatron – Alignment Ray Stefanski March 6, 2003

CM focuses on controlling outcomes. CM controls change, making sure that its impact is assessed and that every effort is made to prevent erosion of functionality or safety. Configuration Management Applies to any complex system, but we will concentrate today on Tevatron magnet alignment and stability.

Organization I would like to discuss alignment roughly along chronological lines, beginning last Summer when I first got involved. Our baseline dates to We will cover: 1.Data base development. 2.Elevations. 3.Roll measurements. 4.Continuous elevation monitors. 5.Smart Bolt measurements. 6.Summary

Contributors: Bruce Hanna Jim Volk Bob Bernstein Terry Sager George Wojcik AMG Chuck Brown Mike Church Andrey Chupyra Vladimir Shiltsev Mike Syphers MCR Dave Augustine Mechanical Techs Don Edwards Todd Johnson Duane Plant Jim Williams Dave Harding Bruce Brown John Carson Jamie Blowers Ray Hanft Hans Jostlein Crag Moore Aimin Xiao Jean Slaughter Dave Ritchie Norm Gelfand

Quad Elevations from GW 1995

Mike Syphers

Murphy Line

Computer works The Murphy-line differs from the “ideal.” At each station, the difference is about 10 mils. The accumulated beam-offset after one sector is >250 mils. We might take this seriously, if we knew where the Murphy-line was.

BD Development We’re working on a PC RIM DB for magnetic field data. We would like to combine this with Alignment data in the same DB. We want to monitor corrector magnet settings more closely to follow changes as they occur from store to store. Use of SDA.

Elevations The Tevatron now has a vertical network, tied to the Lab coordinates. A1 under repair today. A14-1 may be an example.

B-sector with more data B15-1 B16-1 B17-1

Some history of B16-1 and its neighbors. Memo dated 05/24/99 Mike Church to Alignment Group: Elevation of B-16-1 increased from ” to ” on 05/25/99. Elevation of B-16-1 increased to ” on 03/15/00. US of D-15-5 changed to ”. Elevation of B16-1 is 40.76” measured on 11/19/02. Thanks to Terry Sager.

Aperture Scan 01/07/03 Aperture Scan looks ok! Typical Tev apertures: Quad 3 inch Dipole 2.7 inch C0 lambs ~1 inch B16-1 = 1.36 inch Thanks to Dan Bollinger and Todd Johnson.

CHAURIZE, SALAH J. 03/05/2003 A14-1 Quad A14-2 Dipole Spool to Dipole Quad to Spool Example of mismatch in elevation. Spool Quad to Spool to Dipole interface. Survey and realignment in this area is presently taking place.

Elevation Data at A0 and A1 We really have insufficient data on elevations. We may be missing some important discrepancies.

Results of the Level Run

B-sector elevation corrections Shift is 17.5 mils

E-sector elevation corrections E28-2 E17-1E34-5 Shift is –39.4 mils

Talyvel Clinometer 953 more to go!

Comparison with Survey Data A19 to A 26 outliers

Comprehensive Comparison with Survey Some outliers

Correlation – Roll vs MFG

Quads with Large Rolls

Twist Magnets with twist Greater than 1 mrad.

Effect of MR Magnet Removal Roll: Twist:

Pockets of Interest Magnets with twist Greater than 1 mrad.

Distribution of larger rolls in the Tevatron. 17.4% have rolls > 1 mrad.

Level Meters in the Tevatron Duane Plant, Todd Johnson, Jim Volk, Andrey Chupyra.

Continuous relative elevation monitor.

A16-3 and A16-4 WLM Jim Volk

Quench E-Sector A-Sector B-Sector Some recent history from Todd Johnson’s Tilt Meters.

Have the Tev magnet coils moved in the ensuing years? We measure significant differences in roll between the us and ds ends of many magnets. The alignment lugs were originally set to account for any magnet twist: Both ends of the magnet should have the same roll. Twist may be induced by 4-point stands. There are several things we can do: a. Measure smart bolt settings (will be done tomorrow on a select set of magnets in the tunnel). b. Use the Kaiser coil to check for magnet coil alignment. c. There are about 24 magnets in storage that could be put on a stand and checked. Coupling in the Tevatron

Tev Magnet cross section

Smart Bolt Survey in Tevatron Measurements taken on 2/1982 and 2/18/2003. Dave Harding, John Carlson, Jamie Blowers, And many others. Would induce one Unit of a 1.

Coupling 150 GeV Beam mis-steered in P1 line T:SQ global skew quad circuit at 0 amps Look at betatron oscillation coupling between horz & vert Below are ~ 4 turns of data; 1 st turn on left; scale limits  4mm Horizontal Vertical Ron Moore

This is where we need to get creative. We need to measure magnet positions often, at least once per year.  To follow changes as they take place, we should monitor what magnets are doing over time.  Keep track of changes in corrector magnet currents.  The tilt monitors give a measure of short term changes: We need a cheap way to put 1,000 of these in the ring.  Hans Jostlein has come up with a quick roll measuring device: We hope to be able to do the entire ring in 2-3 days.  In a similar vein, we’ll need some way to quickly measure elevation. Horizontal position checks would be useful also. How do we manage the baseline configuration?

Summary A BD is being developed for Tevatron magnets to include magnetic fields and alignment data. We need to complete elevation measurements. A14-1 was a revelation. A horizontal survey network is in the design stage. A continuous position monitoring system is being developed. What can we say about twist. We may want to realign shims within the iron yoke magnets.