Transcript Drive Laser Commissioning Experience

Drive Laser Commissioning Experience
Reminder of requirements on Drive Laser
Thales laser
Transport system
Commissioning in three areas
Thales laser and it’s specs
Beam conditioning and transport
Virtual cathode alignment
Lessons learned – remaining issues
Future
April 16, 2007
Drive Laser Operations
1
Bill White
[email protected]
UV pulse goals
•
•
•
IR to UV conversion efficiency > 10 %, 2.5 mJ output @ 255 nm
252-258 nm, < 2% energy stability
120 Hz, MTBF > 5000 hours
Spatial Profile
FWHM = 1.2 – 3.0 mm
Temporal Profile
FWHM = 10 ps
(5-20 ps)
flat-top, < 8% peak-to peak
April 16, 2007
Drive Laser Operations
90-10 rise and fall
times < 1 ps
2
Bill White
[email protected]
Thales Laser system
Stretcher
UV
Conversion
Dazzler
Preamplifier
Compressor
Oscillator
Final
Amplifier
Regen
April 16, 2007
Drive Laser Operations
3
Bill White
[email protected]
Transport
Vacuum
cell
ZoomLaser
Bay
L4
Beam shaper
L3
L1
L2
Table in
the
tunnel
Virtual
Cathode
Camera
Photocathode
Powermeter
Transport
tube
Steering
system
L5
Polarizer
Waveplate
Shutter
Launch System
L6
April 16, 2007
Drive Laser Operations
4
Bill White
[email protected]
Active
Steering
Stabilization
Active Steering Stabilization
M6
In order to meet centroid
position stability requirement
(min 60μm) M6 should be
stabilized with 35μrad
accuracy
Sensitivity of the mirror
mount 7arcsec – 34 μrad
Laser Bay
Transport
Tube
M4
From Virtual
Cathode
Table in the
tunnel
C2
Camera
M5
M3
Camera
To Photocathode
April 16, 2007
Drive Laser Operations
M2
Steering Stabilization
system test is underway
5
C1
Bill White
[email protected]
Transport System in the Laser Bay
Remotely Controlled Mirror
Beam Size Adjustment
Lens
Shaper Input Adjustment
To Transport tube
Laser Output
April 16, 2007
Drive Laser Operations
6
Bill White
[email protected]
Shaper
Optical System next to the Photocathode
From Transport tube
Steering
Stabilization Camera
Remotely
Controlled Mirror Lens
Virtual Cathode
Steering
camera
Stabilization Camera
Lead Block
Lens
Remotely
Controlled Mirrors
Powermeter
Lead Blocks
Photocathode
April 16, 2007
Drive Laser Operations
In vacuum mirror
7
Bill White
[email protected]
Transport Commissioning
Transport
Shaper
Diagnostics
Characterization
Calibration of diagnostics
GTL Installation
Virtual Cathode
April 16, 2007
Drive Laser Operations
8
Bill White
[email protected]
Timeline - Laser Commissioning
• Laser table and LSS in Vault
• Feb 13th – Began
taking UV into vault
• Feb 23 – GTL
installation began
• VC March 1 to March
12.
• Gun Installation began
March 12.
• ARR April 4
• Beam April 5
April 16, 2007
Drive Laser Operations
9
Bill White
[email protected]
Commissioning Issues
Better Schedule
coordination
Too many people
all working in
small space
Minor problems
have widespread
impact
Because of
shortened laser
commissioning,
some laser
commissioning will
continue with
injector
commissioning
April 16, 2007
Drive Laser Operations
10
Bill White
[email protected]
Commissioning Issues
Streak Camera
April 16, 2007
Drive Laser Operations
Cross correlator
11
Bill White
[email protected]
Temporal Pulse Shaping
The achieved temporal pulse shape meets physics
requirements for the injector commissioning
Plan to improve the temporal shape
Replace the Lyot filter in the regen amplifier by the edge
mirrors – this will reduce oscillations
Continue working on the Dazzler settings and the
optimum UV conversion crystals lengths
Thales engineers are coming back in September to
continue working on shaping
Plan B – to use stacking of Gaussian pulses
Design and parts for pulse stacking are in place
April 16, 2007
Drive Laser Operations
12
Bill White
[email protected]
Commissioning Issues
Transport Tubes
10m long
Hydro-carbons coating and
damaging inside of windows
when exposed to UV
Dust inside tube settling on
inside of windows – Damage
and diffraction
Will go to less expensive
windows and on site pump so
the windows can be replaced
more quickly.
April 16, 2007
Drive Laser Operations
13
Bill White
[email protected]
Commissioning Issues
Newport aspheric telescope
Converts Gaussian to flat-top
GBS-UV H
Requires good Gaussian input
Very sensitive to alignment
Aperture is just as good
and much simpler to align
Allows flexibility
Simplifies overall transport
April 16, 2007
Drive Laser Operations
14
Bill White
[email protected]
Commissioning Issues
Oscillator Problems
Picomotor translation stage
instability
Femtolase will replace
Coarse control currently
disabled/manual
Phase ambiguity due to locking
at 476MHz
Impacts phasing of RF
Can make double pulse
Could be solved with newly
available upgrade
Replacing this oscillator will solve
both problems and provide
greater seed energy
April 16, 2007
Drive Laser Operations
15
Bill White
[email protected]
Future - Hand Over to Ops
Now
Develop procedures for laser
Automate things that can and need to be automated
August 07 Down
Train Operations Group on typical Operation Procedures
Hand off laser by Jan 08
Laser Group will support Ops
Scheduled Maintenance
Issues that arise outside of the typical operation
envelope
April 16, 2007
Drive Laser Operations
16
Bill White
[email protected]
End
April 16, 2007
Drive Laser Operations
17
Bill White
[email protected]