Post on 18-Apr-2022
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Diamond Light Source: Overview and Status Richard P. Walker
on behalf of the Diamond Machine Project Team
1. Introduction
2. Machine description
3. Commissioning
4. Status and future plan
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Comparison of 3rd Generation Synchrotrons
Diamond
Swiss Light Source
APS (USA)
PETRA III (Germany)
ESRF
Canadian Light Source
SPring-8 (Japan)
ELETTRA (Italy)
Australian SynchrotronALS (USA)
SOLEIL (France)
SPEAR3 (USA)
BESSY II (Germany)
MAX-II (Sweden)
ALBA/CELLS (Spain)
PLS (Korea)
0
2
4
6
8
10
12
14
16
18
20
0 1 2 3 4 5 6 7 8 9
Energy / GeV
Emitt
ance
/ nm
rad
Diamond is a new Medium Energy, 3rd Generation Light Source, to replace the SRS – the world's first purpose built high energy synchrotron radiation source (now 25 years old)
The largest accelerator project, and the largest scientific investment in the UK for over 30 years.
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Diamond – Main Parameters
Energy 3 GeVCircumference 561.6 mNo. cells 24Symmetry 6Straight sections 6 x 8m, 18 x 5mInsertion devices 4 x 8m, 18 x 5mBeam current 300 mA (500 mA)Emittance (h, v) 2.7, 0.03 nm radLifetime > 10 hMin. ID gap 7 mm (5 mm)Beam size (h, v) 80, 8 μmBeam divergence (h, v) 35, 3 μrad(at centre of 5 m ID)
nominal, non-zero dispersion lattice
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Located at the Rutherford Appleton Laboratory, on the Harwell Science and Innovation Campus:
Central Laser
Facility
ISIS(Spallation
Neutron Source)
DiamondLight Source
Diamond Research Complex (funded, for users of Diamond, ISIS
and CLF)
Hostel(open Sep. '06)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Diamond Project Evolution
1993 Woolfson Review: SRS to be replaced by a new medium energy machine
1997 Feasibility Study (“Red Book”) published3 GeV, 16 cells, 345 m circumference, 14 nm rads
1998 Wellcome Trust joins as partner
Mar. '00 Decision to build Diamond at Rutherford Appleton Lab.
Oct. '00 3 GeV, 24 cells, 560 m circumference design approved
Apr. '02 Joint Venture Agreement signed (UK Govt./WellcomeTrust)Diamond Light Source Ltd. establishedDesign Specification Report (“Green Book”) completed by CCLRC
Jan. '07 Start of Operations
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
235 m
100 MeV Linac
3 GeV BoosterC = 158.4 m
3 GeV Storage RingC = 562.6 m
Experimental Hall and Beamlines
235 m
office building
peripheral labs. and offices
future long beamlines
technical plant
The Diamond Machine
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Linac• 100 MeV Linac of the DESY S-band Linear Collider Type II design,
supplied "turn-key" by Accel Instruments.(DLS supplied diagnostics, vacuum and control system components, and beam analysis software)
• thermionic gun; short (< 1 ns) and long pulse (0.1-1 μs) modes
• 500 MHz sub-harmonic pre-buncher, 3 GHz primary buncher, 3 GHz final buncher
• two 5.2 m constant gradient accelerating sections fed by independent klystrons
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
BoosterEnergy 3 GeVCircumference 158.4 mEmittance 141 nm radRepetition rate 5 HzLattice FODO, missing dipole
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Storage Ring
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Girders
Magnets and vacuum chambers mounted and pre-aligned on precisely machined girders, 3 per cell
Up to 6 m long and 17 T in weight.
mover system allows remote alignment possibility
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Power Supplies
Standardisation- minimum no. of different types- all 1038 power supplies use the same (PSI type) digital controller and ADC cards.
Maintainability and Reliability- plug-in modules- reduced component count- redundancy of 24 V control power and power modules
Analog- Digital-Converter
DSP-controllerincl. PWM generator
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
RF System
IOT-based 300 kW amplifiersLiquid He plant
Supercon-ducting cavities (2)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Both cavities conditioned above the nominal 2 MV accelerating voltage, meeting the specified Qo:
module DLS1 - acceptance test
1E+08
1E+09
0.00 2.00 4.00 6.00 8.00 10.00
Eacc [MV/m]
Q0
before warm-upafter warm-upspecification
5E+09
module DLS3 - acceptance test
1E+08
1E+09
0 1 2 3 4 5 6 7 8
Eacc [MV/m]
Q0
specMay 03, 2006
5E + 8
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Resolution in 2 kHz Bandwidth:<1 μm at >10 mA
Turn-by-turn (1 MHz b.w.):~ 100 μm at 1 mA
100 101 102
10-1
100
beam current [mA]
reso
lutio
n [u
m]
meanmaximumminimumproduction specoriginal spec
10-1 100 101 102
100
101
102
beam current [mA]
beam
cur
rent
dep
enda
nce
[um
]
meanmaximumproduction specoriginal spec
Beam Current Dependence< 1 μm at 60-300 mA
Digital Beam Position Monitor Electronics(Libera, integrated in EPICS)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
provides many different data streams, simultaneously
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Phase I Insertion Devices
under assembly
ready for vacuum
assembly
installed
ready for installation
installedunder bake-out
ready for vacuum
assembly
Status
In-vacuumU27I16
APPLE-II HU64I06
In-vacuumU23I02
In-vacuumU21I03
U27
SCW
U23
ID
Superconducting Multipole Wiggler
I15
In-vacuumI18
In-vacuumI04
TypeBeam-line
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
U23 trajectory and phase errors
rms phase = 2.5o
rms phase = 2.8o
g = 5 mm
g = 7 mm
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
U23 field Integrals4
2
0
-2
-4
20100-10-20
7mm1.0
0.5
0.0
-0.5
-1.0
G.m
20100-10-20mm
7mm
0.4
0.2
0.0
-0.2
-0.4
G.m
-10 -5 0 5 10mm
7mm
After Correction Before Correction
Vertical
HorizontalCentre of device after correction
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Superconducting Wiggler
SCW under test on the experimental hall floor
Field 3.5 TPeriod 60 mmNo. full poles 45Vertical aperture 10 mm
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
ID Installation Status
5m long narrow gap vessel for APPLEII undulator
in-vacuum undulator
superconducting wiggler
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Installation complete: Aug. 3rd 2005
1st beam from gun: Aug. 31st 2005
1st 100 MeV beam: Sep. 7th 2005
Acceptance test mid-Oct. 2005complete:
Machine Commissioning: Linac
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
effect of the sub-harmonic pre-buncher(wall current monitor and 10 GHz oscilloscope)
energy spread measurement
emittance measurement:
Gun Bunch AS 1 AS 2Q3 Q2 D1SR1
Q2
DumpFC3
slit
D2SR2
DumpFC4
WCM1YAG1FC1
YAG2FC2
YAG3
OTR1YAG4
BPM2ICT1OTR2YAG5
BPM3BPM1WCM2
OTR3YAG6
Gun Bunch AS 1 AS 2Q3 Q2 D1SR1
Q2
DumpFC3
slit
D2SR2
DumpFC4
WCM1YAG1FC1
YAG2FC2
YAG3
OTR1YAG4
BPM2ICT1OTR2YAG5
BPM3BPM1WCM2
OTR3YAG6
Linac Diagnostics
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Linac Performance
103103> 100Energy [MeV]
1111< 100Jitter [ps]0.05 rms, 0.16 full0.05 rms, 0.21 full < 0.25Energy variation
[%]
~ 0.2 fwhm~ 0.2 fwhm< 1Pulse width [ns]
0.2< 0.2< 0.5Energy spread [%]
4.82.1> 1.5 / 3.0Charge [nC]
1127< 50y norm. emittance[π.mm.mrad]
1618< 50x norm. emittance[π.mm.mrad]
Multi bunchSingle bunchSpecificationParameter
(Same at 1 Hz or 5 Hz)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
First beam in the Booster (100 MeV, no RF)
Dec. 21st 2005
- with no correctors
Booster Commissioning
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Feb. 13th: Beam surviving for 200 ms between injections at 100 MeV(RF on)
1/e lifetime = 1 s
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
within +/- 5 mm, with no correctors powered
Closed orbit
First orbit correction Feb. 17th
within +/- 1 mm
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
First acceleration to 700 MeV, March 10th
First extraction at 700 MeV, April 4th
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Why 700 MeV ?Water cooling system(part of the Buildings contract) not available.
Temporary systems set up for Linac, Booster RF, Storage ring RF, but not initially for the magnets.
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Booster optimisation (April '06)
2 mA typical, with ~ 70 % transfer efficiency from before injection to after extraction.
Tunes corrected through the ramp
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Optics measurements
Measured response matrix:
Predicted β-beat from LOCO analysiswithin ±15 % Horiz., ±10 % Vert.:
dispersion measurement:
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Storage Ring: Phase I Commissioning (700 MeV)
May 3rd/4th:
First beam in the storage ring –immediately after the septum
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
May 4th/5th:
First turn !
Correctors off
BPM signal at the end of the first turn
Horizontal positionVertical positionIntensity
low intensity due to two quadrupoles with inverted polarity
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Celebrating the First Turn! – 03:00 May 5th 2006
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
May 5th/6th: 4 turns
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
May 19th/20th: 2000 turns (sextupoles on, RF off)
May 6th/7th: 600 turns (sextupoles off, RF off)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
May 20th/21st: 106,764 turns !
May 21st/22nd:0.4 mA, 70% injection efficiency
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
First stored beam ! …
0.5 hour lifetime at 0.5 mA
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
But initially the beam did not accumulate …
4 kicker pulses
difference signals
- believed to be due to differences between the kicker pulse shapes (which were not tuned for operation at 700 MeV)
then after an "optimisation procedure" …..
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
> 2 mA accumulated
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
First Synchrotron Light !- from the visible Synchrotron Light Monitor
0 100 200 300 400 5000
2
4
6
8
10
time (ps)
Inte
nsity
(a.u
.)
σt ~ 24 ps
35 μs
500
ps
First use of the streak camera:
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
3.5 ms
500
ps synchrotron oscillations at injection
0 500 1000 1500 2000 2500 3000 3500 4000-60
-40
-20
0
20
40
60
80
cent
roid
(ps)
time (μs)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Response matrix measurement
tunes generally within 0.4-0.5 of the model
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Closed orbit correctionBest achieved: σx = 1.3 mm, σy = 0.9 mm
- reasonable given the uncorrected girder and BPM positional errors
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Vacuum: first observations of photo-stimulated desorption
beam current
pressure in the e-beam chamber
pressure in the SR beam port
Average base pressure 5 10-10 mbar
Dynamic pressure 1.5 10-9 at 2 mA
Consistent with desorption rate of 10-3 molecules/photon (as expected for a pre-baked, stainless steel system)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Booster 3 GeV Commissioning (June '06)
0 20 40 60 80 100 120 140 160 180 2000
0.5
1
1.5
2
time [ms]
stor
ed c
urre
nt [m
A]
0 20 40 60 80 100 120 140 160 180 2000
250
500
750
1000
dipo
le c
urre
nt [A
] • Started 3 GeV trials on June 7th
• First beam to 3 GeVon June 9th
dipole magnet currentbeam
current
200ms
60kW
1kW
200ms
60kW
1kW
linear ramp of rf power
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Tunes
Tunes constant to ΔQx = 0.07, ΔQy = 0.05
- without corrections to the sinusoidal ramps
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Closed orbit
BPM no.
Time (ms)
Horizontal position (mm)
Vertical position (mm)
Closed orbit can be corrected during the ramp, but is not needed.
After 400 MeVstays constant, within ± 3 mm.
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Extracted Beam at 3 GeV
σx=1.5 mm
σy=0.11 mmin agreement with theory (2% coupling)
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Booster is now ready to inject into the storage ring at 3 GeV.
Stability has however deteriorated, and has been linked in part to mains frequency variations ….which are being investigated
It should however improve after the World Cup !
England match end, June 15th
Mai
ns fr
eque
ncy
Time (min)
First observation of the effect of a major sporting event on accelerator operation ?
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Summary and Future Plan• Phase I storage ring commissioning at 700 MeV has been a
success: - all systems operational- beam stored and accumulated- optics in reasonable agreement with theory
• Booster commissioned at 3 GeV – ready for the next stage
• Installation of IDs and FEs in progress
• Storage ring commissioning will resume in September, when water cooling is expected to be available.
• Beamline commissioning in parallel during October-December
• Start of Operational Phase - first external users, assisting with beamline optimisation - as original target: January 2007
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
Thanks to the Machine Construction and Commissioning Teams,
Richard P. Walker EPAC'06, Edinburgh, June 29th 2006
& thank you for your attention.