Bruno Muratori (for the EMMA team) STFC, Daresbury Laboratory EMMA commissioning 02/09/08
Bruno Muratori (for the EMMA team)
STFC, Daresbury Laboratory
EMMA commissioning
02/09/08
Overview
• What is commissioning ?– Preparing machine for beam
• set-up DAQ & controls & hardware• set-up diagnostic devices required
– Getting beam into the machine & where you want it– Making sure all desired properties are achieved
• for the bunch (full characterisation etc.)• for the machine (e.g. dispersion-free sections)
– Set-up machine for particular experiments– Need as many simulations of the machine as possible !
I. Gun commissioning - complete (December 2007)
II. First energy recovery- will start now (September 2008) !- all procedures are ready (in Wiki)- online modelling (Mathematica based), being
currently developed- get the energy recovery without FEL first
III. Machine tuning - fine beam tuning - phase space manipulation to achieve minimal bunch
length - full beam characterisation - EO bunch length measurements
ALICE commissioning (1)
IV. Energy recovery with FEL- first light from FEL- energy recovery of FEL disrupted beam - commissioning complete
V. ALICE exploitation - CBS experiments- tomography with space charge (in EMMA injection line)- other experiments (e.g. linac transfer matrices measurement)- preparations for EMMA commissioning
ALICE commissioning (2)
ALICE schematic
LINAC
BOO
STER
GU
N
SOL-01
H&V-01
H&V-06BPM-01
BUNCHERYAG-01
SOL-02
H&V-02 BPM-02
Q-01
YAG-02 Q-02
BPM-03
H&V-03 Q-03
Q-04
YAG-03
DIP-01
Q-05
DIP-02
YAG-??
FCUP-01
BPM-04H&V-04
Q-06Q-07
Q-08Q-09
DIP-3
Q-10
YAG-04
Q-11 BPM-05H&V-05
Q-12
INJECTOR
OTR-01BPM-01H&V-01
ST1
OTR-02 DIP-01DIP-02
DIP-03Q-01
OTR-03
BPM-02H&V-02
Q-02 Q-03 Q-04
OTR-04
BPM-01DIP-01
BPM-02SEXT-01
OTR-01
ST1 ARC1
ARC1
Q-01
V-01
Q-02
BPM-03
DIP-02
BPM-04
Q-03
V-02
Q-04
OTR-02SEXT-02
BPM-05DIP-03
BPM-06
OTR-01
Q-01Q-02
BPM-01H&V-01
OTR-02
Q-03Q-04
BPM-02H&V-02DIP-01
DIP-02BPM-03V-03
OTR-03
DIP-03
DIP-04Q-05
ST 2ST 2
ARC 2 PLM-01TCM-01
BPM-04H&V-04
BPM-05H&V-05
BPM-01H&V-01
Q-06Q-07
WIGGLER
ST 3ST 3
Q-01Q-02
Q-03Q-04
OTR-01
BPM-02H&V-02
BPM-01DIP-01
BPM-02SEXT-01
OTR-01
Q-01
V-01
Q-02
BPM-03DIP-02
BPM-03Q-03
V-02
Q-04
OTR-02SEXT-02BPM-05
DIP-03BPM-06
ARC 2
ST4
OTR-01Q-01 Q-02
BPM-01H&V-01
Q-03
DUMP-01
Q-04 Q-05
BPM-02H&V-02
OTR-02DIP-01 DIP-02 DIP-03
BPM-01Q-01
Q-02Q-03
OTR-01
DMP
1 m
Note: scale is for guidance only
ERLP SCHEMATIC DIAGRAM
v.0.2 (15/06/2006)extracted from AO-180/10078/E
• Need similar schematic for EMMA injection line, ring and extraction line (shall be enormously more detailed … !)
Injection Line Commissioning (1)
• I Prepare ALICE as Injector for EMMA– Set required beam energy (e.g. 10 MeV)– Beam characterisation
• Bunch length / Charge / Emittance / Energy spread / other ?
– Hardware commissioning– Controls & online model commissioning
• These should be as comprehensive as possible (within reason)
– DAS commissioning
Injection Line Commissioning (2)
Set initial charge at 1 pC• II Thread beam through injector line
– Cancel dispersion in diagnostic straight– Steering: use steerers & kickers to get beam to given
point & with right angle depending on energy and required septum settings
– Beam characterisation (as much as possible – as always !)
– Comparison with models wherever possible
Injection Line Commissioning (3)
• III EMMA ½ turn → extraction– Threading beam without acceleration– Threading beam with acceleration– Characterisation of beam in both cases (extraction /
diagnostic line)• IV EMMA 1 ½ turn → extraction
– Threading beam without acceleration– Threading beam with acceleration– Characterisation of beam in both cases (extraction /
diagnostic line)
Injection Line Commissioning (4)
• V EMMA 10 turn → extraction– Same as before but
• In one go ?• Step by step ? (i.e. one turn at a time)
– Characterisation of beam in all cases
Set nominal charge (q = 16 or 32 pC)• VI Repeat all of the above• VII EMMA exploitation
– Establish Orbit– Tune measurements– Aperture survey
ALICE
EMMA
ALICE quadrupoles
SRS quadrupoles
New quadrupoles
Faraday Cup
Screen
last dispersivesection
Diagnostics:injection line
Diagnostics – injection line (1)
• OTR Screen in ALICE before extraction dipole• BPMs @ entrance of every dipole in injection line• Straight ahead Faraday cup to measure charge &
energy spread• OTR screen in dogleg for bunch length & energy
measurement• Tomography section: 60 degrees phase advance per
screen with three screens for projected transverse emittance measurements
Diagnostics – injection line (2)
• Last dispersive section:– OTR screen & vertical slit in middle of first section
together with– OTR screen in final section for energy and energy
spread measurements– Vertical steerers for position & angle before ring (to
be used with kickers for steering)– BPM at entrance of EMMA ring for position before
entering
Online Modelling (1)
• Build on ALICE experience– Gun commissioning
• Script to run ASTRA for comparisons / predictions– Injection line
• Run GPT for space charge calculations in ALICE• Script to run ELEGANT / other for remainder of
ALICE– ALICE ring
• Script to run ELEGANT / GENESIS / other codes for lasing etc.
Online Modelling (2)
• Create model of ALICE to EMMA injector line in GPT– Run this model both on & off line for comparisons /
predictions• Create S2E model for all of EMMA in GPT
– Run with field maps & misalignments for comparisons / predictions
– Run all the way to spectrometer & dump in the EMMA extraction line
• Compare this with ZGOUBI models & FFEMMAG models wherever possible
Online Modelling (3)• Ring optics – what things may look like
courtesy S. Machida
Online Modelling (4)• Injection orbit and optics - what things may look like
Set septum and kicker strength
See orbit and optics of incoming beam
courtesy S. Machida
Injection Septum 65°
Kicker
Kicker
Cavities x 19
Extraction Septum 70°
Kicker
Kicker
Screen
Wire Scanner
Wall Current Monitor
Wire Scanner
Screen
BPM x 82
D Quadrupole x 42F Quadrupole x 42
16 Vertical Correctors
IOT Racks (3)
Waveguide distribution
EMMA Ring
KickerPowerSupplies
SeptumPowerSupply
SeptumPowerSupply
KickerPowerSupplies
Establishing the orbit (1)• Look at Beam Position Monitor (BPM) one by one from the
injection point (not symmetric → not straightforward)• Adjust initial beam position (x,x’,y,y’) as well as Quad
current and position
BPM
Establishing the orbit (2)
• Double focusing lattice (QF and QD)• Bend fields are created by shifting quadrupoles
QFQD
Linear slide
• 4 knobs– QF and QD strength– QF and QD position
(horizontally)
• 4 parameters to fit
– Qx and Qy
– TOF shape and offset
ERLP
EMMA
SRS quadrupoles
New quadrupoles
TD Cavity
spectrometer dipoleDiagnostics:
extraction line
Diagnostic linedeflecting cavity tomography EO
spectrometer
NEW DIAGNOSTICS BEAMLINE LAYOUTSpectrometer BPM @ dipole entranceScreenFaraday Cup
E-O Monitor
Screen x 3Tomography Section
Wall Current Monitor
BPM & Valve
SRS Quadrupoles x 6
New Quadrupoles x 4
ALICE
New Dipoles (43°) & BPMs at dipole entrance
Current measurement Longitudinal profile
Position measurement
New Quadrupoles x 4
Screen& Vert. Slit
Emittance measurement
Extracted momentum
Location for Transverse Deflecting Cavity(NOT IN BUDGET)
Screen
Measurements in diagnostic line
• Energy– First dipole & spectrometer at end with OTRs
• Emittance– Quadrupole scans & tomography 60° phase
advance / screen– Equivalent set-up in injection line for comparisons
• Bunch length– EO monitor downstream of tomography– No profile information
Measurements with TDC
• Slice emittance & transverse profiles given by
– knowledge of R12 from TDC to screen
– horizontal dimension on screen gives slice emittance– vertical dimension gives bunch length
• Slice energy spread given by– streaked beam and spectrometer
12 sind sR 01 11 12''01 21 22
xx R R
xx R R
Experiments on EMMA
• Cross different large resonances• Measurement of time of flight
– Change frequency until no synchrotron oscillations– Frequency then translates into TOF– Hence find minimum of TOF
• Relationship of TOF to lattice parameters / tune– Tune vs. energy
• Study variation of all parameters to lattice properties• Interpretation of BPM readings
– Not all identical & only symmetry every other cell– Important to model all BPM readings → GPT / other
Aperture survey
• Phase space at injection• Scan aperture in phase space with a pencil beam• See S. Tzenov’s talk for more details
• When is normalized acceptance is 3 mm rad ?• Explore acceptance at all energies• Should also be modelled with FFEMMAG, GPT & others• To be done at all energies from 10 to 20 MeV
x’
/
x
/
pencil beam
Conclusions / Discussion
• Commissioning for EMMA will be a lengthy procedure !• As many models as possible are required for all aspects
of the machine– At all energies– For all lattices
• These may be far from
perfect but should give
insight into the trend or
pattern of beam behaviour e.g. ALICE solenoid scan• Online models should also be done where possible &
necessary
0
5
10
15
20
300 320 340 360 380 400
SQRT (XY)FWHM (Astra)
SQ
RT
(X
Y),
mm
B1, G
SOL-01 scanBeam size (FWHM) on YAG "A"Q = 54pC (#712)