SuperKEKB Event / Timing Controls< kazuro.furukawa @ kek.jp >Timing system towards SuperKEKB
controls
Kazuro Furukawa
for Control Group of SuperKEKB< kazuro.Furukawa @ kek.jp >June 2011.

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Accelerators at KEK
Mt. Tsukuba!
J-PARC!
(at Tokai Site)!

(Super)KEKB!
PF-AR!

ATF!

STF!
cERL!

PF!
Linac!

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

KEKB Operation Improvement up to 2007

Apr.2003
Dual Bunch e+May.2000

Feb.2005
Continuous
Injections

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Sometimes injection needed simultaneously

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Fast beam switching or Simultaneous InjectionKEKB Luminosity degradation on beam studies at
PF and PF/AR
Future SuperKEKB injections with shorter lifetime
Sensitive luminosity tuning with Crab cavitiesPF (and PF-AR) top-up injections for higher quality
experiments
CERN/PS switches beams every 1.2s (PPM)SLAC/SLC switched beams at 180 Hz
KEK Linac had switched beams 360 times a day in 2008
(just before simultaneous injection)
10~120seconds per switching
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Requirements
Maximum beam rate of 50Hz x 2bunches should be kept
Most pulsed power supplies were designed to operate atconstant rate (a restriction to beam mode pattern)Most linac magnets were not pulsed (except positronfocusing coil)Thus, it took much time for mag-field standardization

Approx. 1000 devices in linac
600 active devices (gun, RF, magnets, etc), 100 passive devices (BPM,
WS, etc), and static devices

20ms beam switching became the solution

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Timing system domain
Timing domain
 20milli-second - Pulse-to-pulse, Beam mode flavors,
 Micro-second - pulsed power supplies
 Nano-second - Shape of pulses for pulsed microwave
 Pico-second - Beam timing, instrumentation
 < pico-second - Microwave phases

Hardware media / software Microwave – we always need this Pulse shape, phase control

 Event timing controls – intelligent timing
 Pulse-by-pulse event manipulations
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Detailed requirement at SuperKEKB
 Stable multiple frequencies (114, 571, 1298, 2856, 509MHz)
 Beam bunching for large-current positron single-bunch generation
 Need integer relations (common freq. 10.38MHz)

 Injection timing precision of 30 picoseconds
 Integer relation to (Super)KEKB for aperture at IP
 Accidental coincidence for PF and PF-AR with less severe condition

 Independent Circumference corrections at KEKB, PF, PF-AR KEKB changes 4x10-7, PF and PF-AR changes 4~20x10-6

 2bunches in a single pulse (50Hz) Separated by 96ns (common freq. 10.38MHz)

 Simultaneous top-up injections to 4 rings SuperKEKB HER/
LER, PF and PF-AR
 Common beam transport to KEKB and PF-AR will be upgraded
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Hardware and Operation Improvements
Separate BT for PF (2005)
Pulsed bending magnet for PF (2007)
PF beam from common gun (A1) (2007)
Beam charge safety interlock (2007)
Event-based fast control system (2008)
Pulsed steering magnets (2008)
Electron bypass hole at positron target (2008)
Interface between ring-linac RF (2008)
Multi-energy linac optics (2008)
Simultaneous injections (Apr.2009)
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Linac Energy Profile
B!

A!

R!
C!

1!

2!

3!

4!

5!

Energy(GeV)!

deceleration!

e-: 0.1nC!

2.5 GeV → PF!

1.7!

8.0 GeV → HER!

e-: 1.0nC!

ion!
accelerat

1.7!

e-: 10nC!

e+: 1nC!

1.7!

R!
EPICS Collaboration Meeting / NSRRC

3.5 GeV → LER!

end of LINAC!
Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Power Management
Power management at each power source of 60 50-MW power sources
 In order to maximize the power But not to increase the trip rate Interlock at a reflection level VSWR of 1.4
 If a trip rate is higher, the voltage is lowered Surveyed statistically every week

Some sources will be stand-by state As backups, if the energy is enough KEKB e+ has several stand-by, KEKB e– has typically one

Energy conversion
 Energy gain = constant x sqrt( power )EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Linac Energy Management

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Crest Phase Calibration
Each power source with slow phase shifter Energy measurement scanning the phase shifter Primitive but reliable, while there were several methods
 Chicken and egg issue exists on bootstrap
 If no beam at the end, no measurement possible

 Every several month at least after the long
shutdown
 Automated measurement takes ~2hours for 60 sources Result is saved as a reference to other software If the voltage was changed, nominal crest change isapplied (1kV => ~8degree) (to be measured later)
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Typical Automated Phase Calibration

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Two-bunch Energy Equalization
Two bunch in a pulse Energy compensation
 Depending on beam chargeFast timing adjustment
 Automated measurement Same procedure As crest phase measurement
 With ns timing as a variable

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Energy Profile
8 driver klystrons with fast phase shifters
 Each manage ~8 high power klystrons
 Define the overall energy profile With Small phase angle (from the crest)
 Energy spread compensation depending on beam charge

4 klystrons with fast phase shifters
 Forming two energy-knobs to adjust the energies Before the arc and at the end of the linac

 Not to enlarge the energy spread Two klystrons are grouped

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Fast Controls
~150 parameter switching within 20ms
Keep most of magnet fields with compatible optics
Control llrf to change energy

Pulsed magnet triggers and delays
Delays to keep the constant rate for certain power-supplies

LLRF phases and delays
Gun voltage and fine delay
Interface to bucket selection, etc
(Ethernet-based controls are not reliable enough?)
FPGA and fiber-optic RocketIO might be the way ?
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Old timing system
 Distribution of RF and trigger fiducial
 Many delay modules (~200)
 Did not need fast controls
 KEKB ring has additional slow (µs) events (8bits)

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Timing System

Old Timing Station

EPICS Collaboration Meeting / NSRRC

New Event Receiver Station
with 14 outputs

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Ring - Linac Separate oscillators
 Dispersion measurement at ring
 Phase lock / release at high (rf) / low (revolution) frequencies

 Precision < 30ps
 Small aperture at the collision point

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Event System
Simultaneous Injection
to KEKB-HER, KEKB-LER, and PF, PF-AR
2.5GeV to 8GeV, 0.1nC to 10nC

Stable stored beam current at three rings
Should improve collision tuning with Crab cavities
Should improve the quality of experimental data at PF

Fast switching of many device parameters
In 20ms / 50Hz
Should be reliable because beam power is much different

MRF Series 230 Event Generator / ReceiverVxWorks 5.5.1, MVME5500 (Originally with RTEMS but…)
Timing precision less than 10ps is sufficient (TD4 provides 3ps)
Multi-mode fiber, and single-mode fiber for longer distance

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Event System for Simultaneous Injection
 MRF’s series-230 Event Generator / Receivers
114.24MHz event rate, VME64x and VxWorks v5.5.1
50Hz fiducials
 EPICS R3.14.9 with DevSup v2.4.1
More than hundred 17 event receivers up to now
50Hz-Analog/Timing data
Central!
Event Generator!
Multi/single-mode fiber
Timing precision is < 10ps.
 < 1ps with external module.

SH_A1!
KL_B5/B6!

SB_B!

Injection!

SB_A!

e­	
  Gun!
ARC!

96ns

e– BT (PF: 2.5GeV, 0.1nC)!

>100nsCont-ABC!
KL_51/52!
SB_C!

SB_1!

SB_2!

SB_3!

SB_4!

SB_5!

e+ BT (KEKB: 3.5GeV, 2nC)!

	
  

e+	
  TargetCont-1!

>100ns
96ns

Cont-2!

Cont-3!

Cont-4!

Cont-5!

Event Receivers!
EPICS Collaboration Meeting / NSRRC

e– BT (KEKB: 8GeV, 2nC, !
PFAR: 3.0GeV, 0.1nC)!

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Linac Event System
Satisfies the requirements

CPUEvent rate : 114.24MHz (bit rate : ~2.3GHz)
Fiducial rate : 50Hz
Timing jitter (Short term) : ~8ps
No. of defined events : ~50
No. of receiver stations : 17
No. of Fast parameters : ~130
CPU stopped 4 times
since Sep.2008
for 18 stations

EPICS Collaboration Meeting / NSRRC

EVG
EVR
Opt. Fan-out

EVR & LLRF

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Synchronization Scheme
Synchronization Req.

for PFKEKB : < 30ps
PF : < 300~700ps

Linac SHB!
114.24MHz!
PF
Circumference
Correction!

Flip-flop!
Flipflop!

PF Revolution!
1.6 MHz!

Flip-flop!

Event
System!

50Hz!

Linac rf isSynchronized to KEKB
rf
Event Clock is114.24MHz
We have to manage

AC Line Sync.!

BucketSelection!

Event
System!

for KEKBClock!
Fiducial!
114.24 MHz!

SHB1 Phase
Control!

x 5!
RubidiumSG!

HER/LER
Injection
Phase Control!

571.2 MHz!
10 MHz!

SG!

x 5!
2856 MHz!
X 49 ÷ 275!

KEKB HER/LER
Circumference
Correction!

508.89 MHz!

HER/LER!
BucketSelection!

EPICS Collaboration Meeting / NSRRCSHB2 Phase
Control!

508.89 MHz!

Acc. Phase,
Timing Control

Circumferencecompensation
Bucket selection
Injection phase
controls

÷ 5120!
99.39 kHz!
KEKB
Revolution!

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Beam bucket selection at KEKB
Beam pattern restrictions for beam intervals
Select bucket where the stored current islow, partially independent on the fast timing KEKB has 5120 buckets at 509MHz
 Common frequency between Linac – Ring,
10.38MHz corresponds to 49 buckets (96ns)
 We can select any buckets if we wait maximum of
5120 x 96ns = ~500µs

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Beam Mode Pattern Generation
Pulse 1!

Pulse 2!

Pulse 3!

Beam Mode 1! Beam Mode 2! Beam Mode 3!

Pulse n!
………!

Beam Mode n!

n+1 …!

Main event
Preparation eventcodes forcodes for ʻn+1ʼ!
ʻnʼ! mode
 Every pulse (every 20ms) corresponds to a beam 10 different beam modes are defined (for KEKB e+, etc)
 One beam pulse may contain several event codesAt least one main code and a preparation code for the next pulse

 About 50 event codes are definedSome events correspond to many functions, and others to specific devices

 Beam pattern buffer length (n) can be 2 to 500 (20ms x 500 = 10 seconds)
 A new pattern can be loaded at the end of the previous pattern Otherwise, the pattern repeats forever.

 Main events and preparation events in sequence Main events trigger timing signals
 Preparation events trigger software to exchange analog and delay parameters
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Event Manipulation
Human Operator

Injection Programs

Arbitrate and Generate Beam Mode Pattern (in PythonTk)
considering priorities of the rings
equalizing pulsed power supply intervalin 4 arrays (waveforms) of length 2 (40ms) to 500 (10s)each element corresponds to a 20-ms time slot and a beam mode �Generate Events for the Next 20-ms Time Slot (in Event Generator)
reading two consecutive elements from the beam mode patterngenerate several events for the next pulse
generate preparation events for the next after next�

Generate Signals based on Received Events (in Event Receiver)generate pulsed signals as prepared in the previous time slot
program the signals (enable/disable, delays, etc) for the next
start to generate analog signals for the next�
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Beam Mode Pattern Generators
 Pattern panel arbitrates requests
 From downstream rings with priorities, or human operators
 There are several pattern rules due to pulse device features andlimitations
 Pattern arbitrator software was written in scripting languages to meet
daily changes during the commissioning stage
Remote controlled automatic pattern arbitrator!

Manual pattern generator!

Typical operation in 2009.
~25Hz for KEKB LER
~12.5Hz for KEKB HER
~0.5Hz for PF
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Parameters
Parameters switching via Event system
LLRF phase/timing : 14x4
HP RF timing : ~60
Gun voltages, picosecond delay : 4
Pulsed magnets/solenoid : 14
Injection phase : 2
Bucket selection : 2
BPM : ~100x3

Basically sufficient for fast beam mode switchingMore parameters comingIntegrity monitors
Improved slow beam feedback, fast feedback, etc.

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Linac Event System
Satisfies the requirements

CPUEvent rate : 114.24MHz (bit rate : ~2.3GHz)
Fiducial rate : 50Hz
Timing jitter (Short term) : ~8ps
No. of defined events : ~50
No. of receiver stations : 17
No. of Fast parameters : ~130
CPU stopped 4 times
since Sep.2008
for 18 stations

EPICS Collaboration Meeting / NSRRC

EVG
EVR
Opt. Fan-out

EVR & LLRF

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

LLRF
LLRF Timing/analog signals are essential for absolute energy,
energy spread, and dual-bunch energy equalization
Signals are switched pulse-by-pulse
Value changes are triggered by a preparation eventDriver klystrons (SB), energy tuner klystron (KL), andsub-harmonic bunchers (SH) are managed
by the event system

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing ControlsMore Measurement Technique
Switching between Four Rings
 Challenging to improve beams during operation

Event-based Controls may Help More
 No-destructive measurements with four beams
 Stealth (used beam-pulse) measurements
 With beam deflector

 Dithering pulse-by-pulse If very good resolution was achieved

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

KEKB Operation Improvement (base of SuperKEKB)
Belle/KEK

May.2000
Apr.2003
Dual Bunch e+
Feb.2005
Continuous
Injections
Dec.2008
Crab Cavities andSimultaneous Injection
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Top-up Beam Currents at Storage Rings
Beam currents
were kept
KEKB 1mA (~0.05%)
PF 0.05mA (~0.01%)

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Towards SuperKEKB
Nano-beam scheme at SuperKEKB
 Requires low-emittance large current beams
 Photo cathode RF gun for e- 7GeV, 5nC
 New capture section and new damping ring for e+ 4GeV, 4nC

 40 times more luminosity

 Design of damping ring
 Selection of RF Selection of harmonic number Injection to PF-AR
 Common BT to KEKBKEKBSuperKEKB

e–

e+

e–

e+

8GeV

3.5GeV

7GeV

4GeV

1nC

1nC

5nC

4nC

100µm

2000µ
m

20µm

10µm

 PF-AR Injection needs 5-10 minutes 2bunch 2bunch 2bunch 2bunch Shorter life time of 10min at SuperKEKB
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Damping ring injection for SuperKEKB
 Accommodate 2 bunches 2 pulses

e− Gun!

KEKB�

ARC!
Primary e– (4GeV, 10nC)

For e+ 25Hz e‒ 25Hz
Inj.

D.R.

e+ 1

e+ 1

e‒ 2

e+ 1

e‒ 2

e+ 3

e+
3,1

e+ 1

e‒ 4

e+ 3

e‒ 4

e+ 5

e+ 5,3

e+ 3

e‒ 6

e+ 5

e‒ 6

e+ BT (KEKB: 3.5GeV, 0.6nC)!

e+ Target!

Ext.

e+ DR (1.1 GeV, 4nC)!
e− Gun!
ARC!

EPICS Collaboration Meeting / NSRRC

Primary e– (3.5GeV, 10nC)

SuperKEKB�
e+ BT (KEKB: 4GeV, 4nC)!

e+ Target!

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Development of EVR/PLC at SSRF
 For Yokogawa FAM3 PLC with F3RP61 linux CPU
 Prototype in 2010
 Production version at Oct.2011
 Will simplify the additional stations

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

SuperKEKB timing software upgrade Basically the same configuration as KEKB Intelligent panels – pulse-by-pulse EVG Sequences – EVR PV databases Need to upgrade to newer device driver/support with new
register mapping Under evaluation with newer firmware/EPICS support

 Need more coordinated beam pattern generation
 Need dependencies between pulses Need to decide whether to change phases at DR Need synchronization to laser rf gun
 Laser based on local oscillator, need PLL and stabilization strategy

 Possible more addition of event receivers to BT and Rings
 Possible upward links for bucket selection data (SSRF or MRF)
 Linux-based device support for EVR/PLC from SSRF on F3RP61
 Should be simple (?) based on standard FAM3 bus access
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Summary
 Simultaneous injections to three rings (KEKB HER/LER
and PF) achieved
 Challenging for four rings (incl. PF-AR) with a dampingring Event-based controls : another layer of controls bellow
EPICS slow controls
 <http://www-linac.kek.jp/cont/epics/event/> There should be much room to establish further
controls utilizing beam monitors, rf monitors, and more
 With Phronesis (Ability to understand the universal truth, Greekword) we can enjoy our accelerator more

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Thank You谢谢您EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Thank you

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

BackupEPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Parameters
Parameters switched via event system
LLRF phase/timing : 14x4
Overall energy profile, dual-bunch energy equalization, final energy adjustment

HP RF timing : ~60
Energy profile and backup management

Gun voltages, picosecond delay : 4
Beam charge selection, dual bunch selection, bunchingPulsed magnets/solenoid : 14
Beam transport selection, orbit controls, positron focusing

Injection phase interface : 2
Bucket selection interface : 2
BPM : ~100x3

Sufficient for fast beam mode switchingIntegrity monitors soon
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Three Virtual Accelerators
 Controls and instrumentations are essentially mode-dependent, andmutually independent Selecting a real machine out of three virtual machines Managing three parameter sets (four under SuperKEKB environment)e− Gun!

e– BT (PF: 2.5GeV, 0.1nC)!

PF Injection�

ARC!

e+ Target!

Event-based
Control Systeme− Gun!
ARC!

KEKB-LER Injection�

Primary e– (4GeV, 10nC)

e+ BT (KEKB: 3.5GeV, 0.6nC)!

e+ Target!
e− Gun!
ARC!

KEKB-HER Injection�
e+ Target!
e– BT (KEKB: 8GeV, 1.2nC)!

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Three-fold Independent Closed Loops Feedback loop software act on one of three virtual machines Managing independent parameter setse− Gun!

e– BT (PF: 2.5GeV, 0.1nC)!

PF Injection�

ARC!

e+ Target!

Event-based
Control
Systeme− Gun!
ARC!

KEKB-LER Injection�

Primary e– (4GeV, 10nC)

e+ BT (KEKB: 3.5GeV, 0.6nC)!

e+ Target!
e− Gun!
ARC!

KEKB-HER Injection�
e+ Target!
e– BT (KEKB: 8GeV, 1.2nC)!

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

For SuperKEKB Complex
 Slightly More Complicated Conditions with DR
 Harmonic number of SuperKEKB-MR (509MHz) is 5120
 Common frequency between Linac-MR is 10.38MHz (49 buckets, 96ns)
 DR should have common frequency, RF chosen to be 509MHz
 2x2 bunches, bunch separation of 49-bucket , kicker rise/fall time of 100ns
 Jitter (wait-time) of HP modulator (50Hz) must be <~2ms Harmonic number of DR was chosen to be 230

 In order to Select All the Buckets in SuperKEKB MR
 Active (Pulse-to-pulse) LLRF controls necessary at linac
 Better LLRF monitor is required Dependency between pulses increases

 For PFAR Injection
 Positron have to be used to share the beam-transport
 Independent circumference controls will interfere

PF can use 2.5GeV electron with accidental synchronization (<~300ps)

 More investigation underway
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

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SuperKEKB Event / Timing Controls

Event System Consideration for SuperKEKB
Possibly Cascaded Event Systems
For damping ring, main ring and other sub-systems

New firmware with new register map
For newer device support software in EPICS community
Several local modification already, want to synchronize with other institutes

Several institutes in Asia may use CompactPCI as well
Whether PLC version can use the same environment??

Several fast control projects for SuperKEKB
Several embedded systems with PLC EVRs for RF stations
Bucket selection to cover both damping and main rings
In KEKB, separate system was used and selection signal was used as AC to EVGFast feedbacks in Linac and in main ring

Several others
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

47

SuperKEKB Event / Timing Controls

BPM
Tektronix DPO7104 can acquire data at >50Hz.
With embedded EPICS

Beam modes are recognized by events through CA network.
Clients can monitor data of an interested beam mode.
26 oscilloscopes are installed.
100 BPMs are synchronized. (100 BPMs at BT as well soon)

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

48

SuperKEKB Event / Timing Controls

Measurement and Data Acquisition
Originally much efforts to develop
detectors, shaping amplifiersNo budget for all BPMs

Switched to direct waveform acquisition
Minimized active components, thenminimized calibration tasks, maintenanceEqual-length cables
One oscilloscope covers about 5 BPMs, or
combined 20 (or 40) waveforms
5 - 10Gs/s (with additional interpolation)
Possible to measure dual bunches
Solved many issues at once!
Extract each signal, apply calibration
factors, send to upper layer at 50Hz

EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

49

SuperKEKB Event / Timing Controls

Embedded IOC on OscilloscopeDPO7104, 10Gs/s, 4ch, 8bit
Windows-XP
Cygwin software development environment
Microsoft Visual C++ 2008http://www-linac.kek.jp/cont/epics/win32/

EPICS 3.14.8.2
Fast data-acquisition at ~150Hz was tricky, but waspossibleEvent triggers the data acquisition
Beam positions and charges are calculated based on ~30
coefficients, and tagged with beam modes
50Hz processing is stable at Linac
Very efficient for us
EPICS Collaboration Meeting / NSRRC

Kazuro Furukawa, KEK, Jun.2011.

50