LCLS Injector Down-Time Work Prioritized for Fall of 2007
September 13, 2007
P. Emma, et al.
Laser Repair and Upgrade (refer to B. White’s more complete list)
Top Priority:
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Install and test new oscillator
Commission laser iris position feedback loop
Second Priority:
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Change magnification for larger spot size on vacuum transport windows
Remove all air currents in laser room to stabilize laser beam
Add energy attenuator where it will not affect temporal shape
Make sure temperature monitors are everywhere needed, with alarm limits
Add anamorphic imaging to remove ellipticity in laser spot
Beamline Repairs
Top Priority (and in order):
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Shim fields for BX12 & BX13 BC1 dipoles (remove and re-measure)
Phase match X-band structure input/output couplers (possibly in situ)
Realign X-band structure – move it 0.6-mm horizontally toward wall
(north)?
Add polarizing filter to OTRS11 to cut synchrotron radiation background
Extend travel of YAGG1 and align (y-position needs to be lowered
significantly)
Fix TCAV roll angle (is presently rolled 2.5º CW looking downbeam)
Inspect OTR2 foil for damage and possibly replace
Repair FC01 and IM01, and reverse and align AM01 mirror
Realign GTL YAG01, YAG02, BPM2, and BPM3 (and more?)
Replace all 20-micron diameter wires with 40-micron (still Tungsten)
Second Priority:
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Realign RF gun (especially in z, where gun is presently 0.3 inches upstream)
Widen BC1 mover range to 300 mm (original design requirement)
Commission injector beamline laser alignment system (after AM01 mirror fixed)
Replace VV03 with remotely controllable vacuum valve (is manual valve now)
Fix roll angle (and database!) for BPM201 & BPMS1
Rotate wire cards in WS04 and WS13 (becomes top priority if wires are replaced)
Fix temporary support (jack stand) under BPM13
Install VVS1 properly (remove C-clamp)
Refine alignment of all components as time allows (QM02?)
Install BPM processor on BPMM14 (take BPMG1 processor if needed) (done)
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Add amplifiers to bunch length monitors to extend dynamic range
Measure permeability of QM02 vacuum chamber
Re-align CQ11 tweaker quad (~1 mm off in x – beam data available)
Fix all OTR/YAG-screen travel so that they no longer get stuck (fail to extract)
Test gear-reducer to fix wire vibration
Beamline Upgrades (if possible)
Top Priority (if any upgrade can be implemented):
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Add an OTR screen nearby PR55 in BSY (or replace) – use OTR1?
Add an OTR screen in sector-30, if time and location determined – use OTR3
(drop for now).
Second Priority:
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Add BPM between WS12 & OTR12 (if possible) (drop for now)
Add color digital camera at OTR12 (see J. Frisch)
RF Systems
Second Priority:
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New LCLS master oscillator (or alternate)
Need an automated procedure/software to fix phase jumps in the LLRF system
Phase the three L1S sections w.r.t. each other (21-1d is 30 out of phase?)
Move RF Hut water temperature regulation sensor to INSIDE of room
Complete software and installation for Klystron PADs
Complete beam synchronous data acquisition for RF system
Provide EPICS feedback loop for LCLS-to-linac RF phase control (Matlab now)
Controls
Top Priority:
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Save/Compare/Restore facility in EPICS
Second Priority:
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Crop camera images in IOC’s and do centroid and rms calculations in IOC?
Add tolerances and alarms on RF parameters