Zack Wolf BFW Fiducialization October 20, Beam Finder Wire (BFW) Fiducialization Zack Wolf, Dean Walters, James Bailey, Eric Lundahl

Zack Wolf BFW Fiducialization October 20, 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 October 20, BFW Specifications LCLS PRD

Zack Wolf BFW Fiducialization October 20, BFW Operation Out: The beam goes through a small beampipe making a smooth transition to external beampipes In: Wires are inserted into the beamline. The whole girder is moved to scan the wires across the beam.

Zack Wolf BFW Fiducialization October 20, BFW Use Either turn quad off, or use wire system to re-center on beam

Zack Wolf BFW Fiducialization October 20, 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

Zack Wolf BFW Fiducialization October 20, Fiducializing the Beam Finder Wire Dean Walters, James Bailey,

Zack Wolf BFW Fiducialization October 20, Cases to Consider Fiducialization Case 1 - Initial installation of the BFW Below is the outline of the Initial Installation followed by the outline of the Replacement of the BFW Case 2 - Replacement of the BFW The 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 October 20, Case 1 - Initial Fiducializing of the BFW Step 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 October 20, 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 October 20, 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 BFW Step 3 - Alignment of BFW/Vacuum Chamber to Undulator Vacuum Chamber

Zack Wolf BFW Fiducialization October 20, 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 October 20, 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 October 20, How Fiducialization Is Really Done Eric Lundahl

Zack Wolf BFW Fiducialization October 20, Optically Find Wires WRT Local Fiducials

Zack Wolf BFW Fiducialization October 20, Locate Tooling Balls With CMM

Zack Wolf BFW Fiducialization October 20, Previous SLAC Experience