Transcript Linac Update

LCLS Linac Update
E. Bong
Facility Advisory Committee Meeting
October 12, 2004
LCLS
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac Update
Brief Overview
L1 & BC1 Progress
LTU & E-Dump Status
Continuing Resolution Impact
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
Nominal LCLS Linac Parameters for 1.5-Å FEL
Single bunch, 1-nC charge, 1.2-mm slice emittance, 120-Hz repetition rate…
250 MeV
z  0.19 mm
  1.6 %
Linac-X
L =0.6 m
rf= -160
14.1 GeV
z  0.022 mm
  0.01 %
135 MeV
z  0.83 mm
  0.10 %
Linac-1
L 9 m
rf  -25°
SLAC linac
21-1b
21-1d
DL-1
L 12 m
R56 0
X
4.54 GeV
z  0.022 mm
  0.71 %
Linac-2
L 330 m
rf  -41°
Linac-3
L 550 m
rf  -10°
21-3b
24-6d
25-1a
30-8c
BC-1
L 6 m
R56 -39 mm
SLAC linac tunnel
BC-2
L 22 m
R56 -25 mm
E-Dump
undulator
L =130 m
LTU
L =275 m
R56  0
research yard
(RF phase: frf = 0 is at accelerating crest)
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
Baseline System Design
1.5-Å SASE FEL Linac:
Requirements
Acceleration to 14.3 GeV (4.5 GeV min.)
Bunch compression to 3.4 kA (gex,y  1.2 mm)
Emittance preservation (<20% ‘slice’, <100% ‘projected’)
Final energy spread (<0.02% ‘slice’, <0.1% ‘projected’)
Minimal sensitivity to system ‘jitter’
Diagnostics integrated into design
Flexible operations (1.5 to 15 Å, low-charge, chirp, etc.)
Compatibility with other SLAC programs
use 2 compressors, 3 linacs
Linac Physics Requirement Document PRD# 1.3-001
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS/SLAC Program Compatibility
Program Changeover Time
15 minutes from LCLS to damped SLAC beam
24 hours from LCLS to undamped ESA beam
Moving Chicanes
Articulates collinear with linac axis for straight-ahead
X-Band Structure Aperture
7mm, smaller than linac scrapers (16.5mm)
Smaller than undamped beam
Moves off-axis, temporary pipe installed
BPM Module Design
Charge Range. LCLS 0.2nC to 1nC. Full ESA beam
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
L1 & BC1 Subsystem
Linac 1 (L1)
Treaty Point LCLS
Injector/LCLS Linac
LCLS Injector
Two short accelerator
structures, refurbished
Quads+BPMs,X&YCOR
Bunch Compressor 1 (BC1)
X-Band
Structure
(NLC)
Quad + BPM,
YCOR,XCOR,
QE, Toroid
Bunch
Compressor &
Diagnostics
Emittance
Diagnostics.
LCLS Linac
Remove 5 S-Band Structures
Electrons
System background 3-D complete
X-Band structure and waveguide network design in progress
BC1 chicane articulation design in progress
Dimensional checks between mechanical layout and physics deck
performed
Work remaining: short accelerators, emittance diagnostics section
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
X-Band System Design
60cm structure from
Fermi
Integrated into
beamline layout
Translation to be
designed
XL4 Klystron
NLC waveguide
components designed
for 8-Pack
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
BC1 System Design Status
Articulated bunch
compressor layout
Dynamic solid modeling
Bend Magnets LLP
Install FY ’06 shutdown
BC1 inter-bend diagnostics package
BPM, collimator, OTR
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac L2, BC2, L3
Except for BC2 in Linac Sector 24, Linac
Sectors 22-30 largely unmodified
System schematics complete
3-D models of area backgrounds near
complete
File management structure for 3-D models
complete
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac LTU Subsystem Schematic
Energy and emittance diagnostics, energy collimation, bunch length
diagnostics and undulator launch feedback
3-D solid automated layout generated from MAD done
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
Multiple Undulator Expansion Capability
LTU
Multiple beamlines NOT in LCLS baseline scope
Baseline design not to exclude possibility of expansion
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
Main Dump and Safety Dump
Main dump electromagnets allow energy
and energy spread measurements
Safety dump permanent magnets deflect
e-beam on BYD failure
Ray traces show no beam transported
through wall in any failure condition
Working with SLAC Radiation Safety for
approval of design
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac Work Plan by Area
Design, Long Lead Procurement, Construction, Installation, FEL Commissioning
Linac Coherent Light Source Project Time Line
Fiscal Year
Quarter
Project Engineering Design
Long-Lead Procurement
Construction
Laser Commissioning
Project Task
2003
2004
2005
2006
2007
2008
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
LCLS Linac Summary by Area
Linac 1
Bunch Compressor 1
Linac 2
Bunch Compressor 2
Linac 3
Linac-to-Undulator
Electron Dump
LLP X-Band
LLP BC1 BC2 Bends
PED
Procure-install
PED
Procure-install
PED
PED
Procure-install
PED
Procure-install
PED
Procure-install
PED
Procure-install
L1, BC1, L2, BC2 and L3 must be installed during
SLAC Linac downtimes.
October 12, 2004
FAC LCLS Linac Update
SLAC Linac Downtimes
Eric Bong
[email protected]
LCLS Linac Organizational Chart
LCLS Linac System
Eric Bong: Manager
Paul Emma: Physicist
Dayle Koturi
LCLS Linac
Controls Liazon
Peter McINtosh
Linac
RF Systems
Leif Eriksson
L1, L2, L3 BC1,
BC2 Integration,
Vacuum
Tim Montagne
LTU & E-Dump
Integration,
Diagnostics
Carl Rago
Mech. Data, RF
Distribution
Magnets
LCLS Linac Mechanical Engineering
Klystron
Department
Engineers
Designers
Fabrication
Klystron
DEpartment
Joe Stieber
LCLS MD
Stephan Davies
LCLS MD
Paul Stephans
LCLS MD
SLAC Mechanical Design
Stanford
ME Grad. RA
Manish Narula
Venkat Srinivasan
Ashish Mitra
New LCLS
ME Hire
SLAC Mechanical
Engineers
SLAC Mechanical
Design
Department
LCLS Installation
Manager
Resources obtained through both direct hire and matrixed from SLAC departments
Resources within groups distributed based on project demands
Communication between systems managed through Interface Control Documents
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac Challenges
RF Stability
Existing system phase and amplitude stable to requirements over several seconds
Stability achievable over longer time scales using bunch length and energy feedback
Bunch Length Measurement & Feedback
Bunch length measurement in R&D at SPPS
Feedback modeling and simulation by J. Wu
Epics/SLAC Controls System Compatibility
Require Epics system to access SLC control system in order to operate existing
equipment required for LCLS
SLC control system needs to access EPICS system to operate LCLS upgraded
equipment required in high power beam operations
Articulated Bunch Compressors
Articulation required for R56 tuning for full range of beam charge
Move for Accelerator centerline for un-damped beam operation
BPM Module Design
Measurement of full range of beam charge required
Two beam e+ e- beam operations place additional challenge on module design
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
Work Plan Next 6 Months
Matrix in Klystron Dept. engineering and design support
for X-Band modulator and LLRF design
Begin procurement of X-Band system
Begin procurement of BC1 & BC2 dipoles
Complete L1 & BC1 design & details
Complete BC1 diagnostics design & details
Begin L2 & L3 system design
Obtain Radiation Physics approval of safety dump design
Continue jitter and feedback modeling
Develop commissioning plans
Develop detailed installation plan
Integrate Injector and Linac engineering groups
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
Linac System Progress Summary
Linac baseline presented to EIR
Linac area schematics complete
Linac Li21-30 3D backgrounds in process
L1, BC1 and X-Band modeling underway
Conducted L1 & BC1 preliminary design review
E-Dump & Safety Dump design under radiation
safety review
Jitter model developed and feedback simulations
conducted, presented at XFEL conference J. Wu
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
Continuing Resolution Impact
Procurement of long lead items delayed
Ramp-up of engineering effort delayed
In most cases delays decrease schedule
float
X-Band Klystron will not be ready for FY’06
downtime
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
End
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
BC 1 X-Band Compressor
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac L2 Subsystem
Parameter Description
Symbol
Value
Unit
Initial to final electron energy
E
0.25 to 4.54
GeV
Bunch length (rms)
z
195
mm
Active length of system
L
329
m
 E /E
1.6 to 0.7
%
s
-41
S-deg
S-band voltage at crest (not incl. ~15% overhead)
DV
5.7
GV
S-band mean phase stability (rms)
D
0.07
deg-S
D V /V 0
0.1
%
Relative energy spread of e - bunch (rms)
RF phase of S-band sections
S-band mean amplitude stability (rms)
Linac Sector 21-3b to 24-6d. Largely unmodified SLAC Linac.
Energy chirps the bunch to allow compression in BC2
RF stability critical
Four wire scanners added for emittance measurement
Requirements PRD# 1.3-004
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac BC2 Subsystem
Parameter Description
Symbol
Value
Unit
Nominal electron energy
E
4.54
GeV
Initial and final bunch length (rms)
z
190 - 22
mm
Active length of system
L
22.5
m
 E /E
0.7
%
Bend angle of each chicane dipole
|q B |
1.98
deg
Nominal |R 56 | (and operational range)
|R 56 |
25 (10 to 50)
mm
LB
50
cm
Relative energy spread of e - bunch (rms)
Length of chicane dipoles
Linac Sector 24-7a to 24-8d, Remove eight S-Band structures
compress a single 1-nC, 195-mm long (rms) electron bunch, at a repetition
rate of 120 Hz, at 4.54 GeV to an rms length of 22 mm
BC2 Bends, Long Lead Procurement Item
Requirements – PRD# 1.3-005
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Linac L3 Subsystem
Parameter Description
Symbol
Value
Unit
Initial to final electron energy
E
4.54 to 14
GeV
Bunch length (rms)
z
22
mm
Active length of system
L
553
m
 E /E
0.7 to 0.01
%
s
-10 or 0
S-deg
S-band voltage at crest (not incl. ~15% overhead)
DV
9.9
GV
S-band mean phase stability (rms)
D
0.15
deg-S
D V /V 0
0.08
%
Relative energy spread of e - bunch (rms)
RF phase of S-band sections
S-band mean amplitude stability (rms)
October 12, 2004
FAC LCLS Linac Update
Linac Sector 25 to 30 largely
unmodified.
Two accelerator structures
added, two structures moved,
two wire scanners moved,
transverse cavity moved, new
OTR screen.
Requirements PRD# 1.3-006
Eric Bong
[email protected]
LCLS Linac LTU Subsystem
Parameter Description
Symbol
Value
Unit
Electron energy range
E
4.5 to 14
GeV
Bunch length (rms)
z
22
mm
Active length of system
L
342
m
Relative energy spread of e - bunch (rms)
 E /E
0.01
%
Bend angle of each of 4 horizontal dipoles
|q B |
0.5
deg
Bend angle of each of 2 vertical dipoles
|q y |
2.3
mrad
New Beamline extending from FFTB muon plug wall in SLAC BSY,
across research yard in new housing to FEL undulator
Transports a 1-nC, 20-mm long (rms) electron bunch, at a repetition
rate of 120 Hz, at 14 GeV to the LCLS FEL undulator
Includes energy and emittance diagnostics, energy collimation, bunch
length diagnostics and undulator launch feedback
Requirements PRD# 1.3-007
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]
LCLS Longitudinal Feedback Simulation
feedback off
feedback on (Integral gain:0.5)
DE / E  -0.0007 %;
DE / E std  0.09 %
DI / I  0.10 %;
DI / I std  8.5 %
Dt  0.003 ps;
Dt std  0.15 ps
Juhao Wu (SLAC)
October 12, 2004
FAC LCLS Linac Update
Eric Bong
[email protected]