beam finder wire (bfw) fiducialization
DESCRIPTION
Beam Finder Wire (BFW) Fiducialization. Zack Wolf, Dean Walters, James Bailey, Eric Lundahl. Need For A BFW. The undulator will not steer the beam. It will just radiate at the wrong wavelength. The BFW allows this to be detected. BFW Specifications. LCLS PRD 1.4-004. BFW Operation. Out: - PowerPoint PPT PresentationTRANSCRIPT
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20051
Beam Finder Wire (BFW)Fiducialization
Zack Wolf,Dean Walters, James Bailey,
Eric Lundahl
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20052
Need For A BFW
The undulator will not steer the beam.It will just radiate at the wrong wavelength.The BFW allows this to be detected.
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20053
BFW SpecificationsLCLS PRD 1.4-004
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20054
BFW Operation
Out:The beam goes through a smallbeampipe making a smooth transitionto external beampipes
In:Wires are inserted into the beamline.The whole girder is moved to scan thewires across the beam.
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20055
BFW Use
Either turn quad off,or use wire systemto re-center on beam
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20056
Fiducialization Accuracy Requirements
1) Locate wire relative to local fiducials (optically): 25 um
2) Locate local fiducials relative to outside tooling balls (CMM): 15 um
3) Repeatability of positioning wires: 80 um in X, 30 um in Y
Rough Error budget:
LCLS PRD 1.4-004
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20057
Fiducializing the
Beam Finder Wire
Dean Walters, James Bailey,
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20058
Cases to Consider Fiducialization
Case 1 - Initial installation of the BFWBelow is the outline of the Initial Installation followed by the outline of the Replacement of the BFW
Case 2 - Replacement of the BFWThe replacement of the BFW is the more difficult case
Since the case of replacement is constrained access-wise, careful placement of fiducials and the BFW/Vacuum Chamber is important.
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 20059
Case 1 - Initial Fiducializing of the BFWStep 1 - Wire to BFW Frame Fiducials
External Moving Fiducials (EMF)
Wire
External Stationary Fiducials (ESF)
Beam Guide
BFW Alignment Stand
On the BFW Alignment Stand the position of each wire can be measured WRT the EMF
Measure the Beam Guide WRT the EMF
With the BFW actuated in each (up & down) position, adjust the stops for each position from the EMF to ESF per nominal dimensions .
BFW Frame
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200510
Bolt BFW Frame to Vacuum Chamber and make vacuum seal.
Adjust the lower stops to place the Beam Guide in the center of the Chamber ports.
Then measure the EMF WRT to CSF
Adjust the upper stops to correctly place the wires WRT the Girder Axis (GA)
Then measure the EMF WRT to CSF
Step 2 - BFW Frame to vacuum Chamber Alignment
Chamber Stationary Fiducials
(CSF)
BFW Chamber Alignment Stand
Case 1 - Initial Fiducializing of the BFW
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200511
The BFW Chamber along with the BFW is placed in the beam line.
Adjust the Chamber supports to place the upstream port in line with the Undulator Vacuum chamber.
The mating flanges will have the ability to self center to each other.
Make up the vacuum flange seal.
There will be the ability to make fine position adjustments after the seal is made.
Re-measure the placement of the Chamber CSF and the EMF WRT to the GA
Case 1 - Initial Fiducializing of the BFWStep 3 - Alignment of BFW/Vacuum Chamber to Undulator Vacuum Chamber
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200512
1. Assumptions for replacement of the BFW.
a) The existing BFW was aligned
b) The BFW/Vacuum Pump chamber stays in place in the beam line
c) The BFW/Vacuum Pump Chamber is supported so that when the BFW is removed that it remains accurately in place
Beam Finder Wire
BFW/Vacuum Pump Chamber
Case 2 - Replacement of the BFW
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200513
Step 1 – This is the same as Step 1 of the Initial Fiducialization Step 2 - In the case of replacement the data from Step 2 in the initial case will be used with the new BFW frame.Step 3 – This is different than the other Step 3 in that the stops will be adjusted in the field using the preexisting data.
This will be more difficult since some lines-of-sight will be blocked due to existing installed equipment.Access to adjustments will also be more awkward in the field then in Case 1 where the adjustments will be made in the lab.The new installed assembly will be measured in both positions after all adjustments have been made to record the final placement.
Case 2 - Replacement of the BFW
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200514
How Fiducialization Is Really Done
Eric Lundahl
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200515
Optically Find Wires WRT Local Fiducials
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200516
Locate ToolingBalls With CMM
Zack Wolf
BFW Fiducialization Procedure [email protected]
October 20, 200517
Previous SLAC Experience