Скачать презентацию Super KEKB Event Timing Controls kazuro
5117f8ea43c8251f1031a53c63f94301.ppt
- Количество слайдов: 50
Скачать презентацию Super KEKB Event Timing Controls kazuro
Скачать презентацию Super KEKB Event Timing Controls kazuro
Super. KEKB Event / Timing Controls < kazuro. furukawa @ kek. jp > Timing system towards Super. KEKB controls Kazuro Furukawa for Control Group of Super. KEKB < kazuro. Furukawa @ kek. jp > June 2011. EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 1
Super. KEKB Event / Timing Controls Accelerators at KEK Mt. Tsukuba e-/e+ Linac should inject beams to Super. KEKB (HER, LER), PF-AR storage rings J-PARC (at Tokai Site) (Super)KEKB PF-AR ATF STF c. ERL PF Linac EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 2
Super. KEKB 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. 3
Super. KEKB Event / Timing Controls Sometimes injection needed simultaneously EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 4
Super. KEKB Event / Timing Controls Fast beam switching or Simultaneous Injection u. KEKB Luminosity degradation on beam studies at PF and PF/AR u. Future Super. KEKB injections with shorter lifetime u. Sensitive luminosity tuning with Crab cavities u. PF (and PF-AR) top-up injections for higher quality experiments v. CERN/PS switches beams every 1. 2 s (PPM) v. SLAC/SLC switched beams at 180 Hz v. KEK Linac had switched beams 360 times a day in 2008 (just before simultaneous injection) v 10~120 seconds per switching EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 5
Super. KEKB Event / Timing Controls Requirements u. Maximum beam rate of 50 Hz x 2 bunches should be kept u. Most pulsed power supplies were designed to operate at constant rate (a restriction to beam mode pattern) u. Most linac magnets were not pulsed (except positron focusing coil) v. Thus, it took much time for mag-field standardization u. Approx. 1000 devices in linac v 600 active devices (gun, RF, magnets, etc), 100 passive devices (BPM, WS, etc), and static devices u 20 ms beam switching became the solution EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 6
Super. KEKB Event / Timing Controls Timing system domain u. Timing domain v 20 milli-second - Pulse-to-pulse, Beam mode flavors, v Micro-second - pulsed power supplies v Nano-second - Shape of pulses for pulsed microwave v Pico-second - Beam timing, instrumentation v < pico-second - Microwave phases u. Hardware media / software v Microwave – we always need this ³ Pulse shape, phase control v Event timing controls – intelligent timing ³ Pulse-by-pulse event manipulations EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 7
Super. KEKB Event / Timing Controls Detailed requirement at Super. KEKB u Stable multiple frequencies (114, 571, 1298, 2856, 509 MHz) v Beam bunching for large-current positron single-bunch generation v Need integer relations (common freq. 10. 38 MHz) u Injection timing precision of 30 picoseconds v Integer relation to (Super)KEKB for aperture at IP ³ Accidental coincidence for PF and PF-AR with less severe condition u Independent Circumference corrections at KEKB, PF-AR v KEKB changes 4 x 10 -7, PF and PF-AR changes 4~20 x 10 -6 u 2 bunches in a single pulse (50 Hz) v Separated by 96 ns (common freq. 10. 38 MHz) u Simultaneous top-up injections to 4 rings Super. KEKB HER/LER, PF and PF-AR v Common beam transport to KEKB and PF-AR will be upgraded EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 8
Super. KEKB Event / Timing Controls Hardware and Operation Improvements u. Separate BT for PF (2005) u. Pulsed bending magnet for PF (2007) u. PF beam from common gun (A 1) (2007) u. Beam charge safety interlock (2007) u. Event-based fast control system (2008) u. Pulsed steering magnets (2008) u. Electron bypass hole at positron target (2008) u. Interface between ring-linac RF (2008) u. Multi-energy linac optics (2008) u. Simultaneous injections (Apr. 2009) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 9
Super. KEKB Event / Timing Controls Linac Energy Profile B PF A R C 1 2 3 4 5 HER/LER/AR Energy(Ge. V) deceleration e-: 0. 1 n. C 2. 5 Ge. V → PF 1. 7 8. 0 Ge. V → HER e-: 1. 0 n. C on ccelerati a 1. 7 e-: 10 n. C e+: 1 n. C 1. 7 R EPICS Collaboration Meeting / NSRRC 3. 5 Ge. V → LER end of LINAC Kazuro Furukawa, KEK, Jun. 2011. 10
Super. KEKB Event / Timing Controls Power Management u. Power management at each power source v of 60 50 -MW power sources v In order to maximize the power v But not to increase the trip rate ³ Interlock at a reflection level VSWR of 1. 4 ³ If a trip rate is higher, the voltage is lowered ³ Surveyed statistically every week u. Some sources will be stand-by state v As backups, if the energy is enough ³ KEKB e+ has several stand-by, KEKB e– has typically one u. Energy conversion v Energy gain = constant x sqrt( power ) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 11
Super. KEKB Event / Timing Controls Linac Energy Management EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 12
Super. KEKB Event / Timing Controls Crest Phase Calibration u. Each power source with slow phase shifter v Energy measurement scanning the phase shifter ³ Primitive but reliable, while there were several methods ³ Chicken and egg issue exists on bootstrap w If no beam at the end, no measurement possible v Every several month at least after the long shutdown ³ Automated measurement takes ~2 hours for 60 sources v Result is saved as a reference to other software ³ If the voltage was changed, nominal crest change is applied (1 k. V => ~8 degree) (to be measured later) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 13
Super. KEKB Event / Timing Controls Typical Automated Phase Calibration EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 14
Super. KEKB Event / Timing Controls Two-bunch Energy Equalization u. Two bunch in a pulse v Energy compensation ³ Depending on beam charge u. Fast timing adjustment v Automated measurement v Same procedure ³ As crest phase measurement ³ With ns timing as a variable EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 15
Super. KEKB Event / Timing Controls Energy Profile u 8 driver klystrons with fast phase shifters v Each manage ~8 high power klystrons v Define the overall energy profile v With Small phase angle (from the crest) ³ Energy spread compensation depending on beam charge u 4 klystrons with fast phase shifters v Forming two energy-knobs to adjust the energies ³ Before the arc and at the end of the linac v Not to enlarge the energy spread ³ Two klystrons are grouped EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 16
Super. KEKB Event / Timing Controls Fast Controls u~150 parameter switching within 20 ms v. Keep most of magnet fields with compatible optics v. Control llrf to change energy u. Pulsed magnet triggers and delays v. Delays to keep the constant rate for certain power-supplies u. LLRF phases and delays u. Gun voltage and fine delay u. Interface to bucket selection, etc u(Ethernet-based controls are not reliable enough? ) u. FPGA and fiber-optic Rocket. IO might be the way ? EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 17
Super. KEKB Event / Timing Controls Old timing system u Distribution of RF and trigger fiducial u Many delay modules (~200) u Did not need fast controls u KEKB ring has additional slow (ms) events (8 bits) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 18
Super. KEKB Event / Timing Controls Timing System Old Timing Station EPICS Collaboration Meeting / NSRRC New Event Receiver Station with 14 outputs Kazuro Furukawa, KEK, Jun. 2011. 19
Super. KEKB Event / Timing Controls Ring - Linac u Separate oscillators v Dispersion measurement at ring v Phase lock / release at high (rf) / low (revolution) frequencies u Precision < 30 ps v Small aperture at the collision point EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 20
Super. KEKB Event / Timing Controls Event System u. Simultaneous Injection vto KEKB-HER, KEKB-LER, and PF, PF-AR v 2. 5 Ge. V to 8 Ge. V, 0. 1 n. C to 10 n. C u. Stable stored beam current at three rings v. Should improve collision tuning with Crab cavities v. Should improve the quality of experimental data at PF u. Fast switching of many device parameters v. In 20 ms / 50 Hz v. Should be reliable because beam power is much different u. MRF Series 230 Event Generator / Receiver v. Vx. Works 5. 5. 1, MVME 5500 (Originally with RTEMS but…) v. Timing precision less than 10 ps is sufficient (TD 4 provides 3 ps) v. Multi-mode fiber, and single-mode fiber for longer distance EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 21
Super. KEKB Event / Timing Controls Event System for Simultaneous Injection u MRF’s series-230 Event Generator / Receivers u 114. 24 MHz event rate, u VME 64 x and Vx. Works v 5. 5. 1 50 Hz fiducials u EPICS R 3. 14. 9 with Dev. Sup v 2. 4. 1 u. More than hundred u 17 event receivers up to now 50 Hz-Analog/Timing data Event Generator Central u. Multi/single-mode fiber u. Timing precision is < 10 ps. SH_A 1 KL_B 5/B 6 SB_B Injection SB_A e− Gun ARC v < 1 ps with external module. 96 ns e– BT (PF: 2. 5 Ge. V, 0. 1 n. C) >100 ns Cont-ABC KL_51/52 SB_C SB_1 SB_2 SB_3 SB_4 SB_5 e+ BT (KEKB: 3. 5 Ge. V, 2 n. C) >100 ns e+ Target Cont-1 96 ns Cont-2 Cont-3 Cont-4 Cont-5 Event Receivers EPICS Collaboration Meeting / NSRRC e– BT (KEKB: 8 Ge. V, 2 n. C, PFAR: 3. 0 Ge. V, 0. 1 n. C) Kazuro Furukawa, KEK, Jun. 2011. 22
Super. KEKB Event / Timing Controls Linac Event System u. Satisfies the requirements v. Event rate : 114. 24 MHz (bit rate : ~2. 3 GHz) v. Fiducial rate : 50 Hz v. Timing jitter (Short term) : ~8 ps v. No. of defined events : ~50 v. No. of receiver stations : 17 v. No. of Fast parameters : ~130 v. CPU stopped 4 times since Sep. 2008 for 18 stations EPICS Collaboration Meeting / NSRRC CPU EVG EVR Opt. Fan-out EVR & LLRF Kazuro Furukawa, KEK, Jun. 2011. 23
Super. KEKB Event / Timing Controls Synchronization Scheme u. Synchronization Req. for PF v. KEKB : < 30 ps v. PF : < 300~700 ps Linac SHB 114. 24 MHz PF Circumference Correction PF Revolution 1. 6 MHz Flip-flop 50 Hz Event System u. Linac rf is Synchronized to KEKB rf u. Event Clock is 114. 24 MHz u. We have to manage AC Line Sync. Bucket Selection Event System for KEKB Clock Fiducial 114. 24 MHz x 5 Rubidium SG HER/LER Injection Phase Control 571. 2 MHz 10 MHz SG 2856 MHz 508. 89 MHz HER/LER Bucket Selection EPICS Collaboration Meeting / NSRRC SHB 2 Phase Control x 5 X 49 ÷ 275 KEKB HER/LER Circumference Correction SHB 1 Phase Control 508. 89 MHz Acc. Phase, Timing Control v. Circumference compensation v. Bucket selection v. Injection phase controls ÷ 5120 99. 39 k. Hz KEKB Revolution Kazuro Furukawa, KEK, Jun. 2011. 24
Super. KEKB Event / Timing Controls Beam bucket selection at KEKB u. Beam pattern restrictions for beam intervals u. Select bucket where the stored current is low, partially independent on the fast timing v KEKB has 5120 buckets at 509 MHz v Common frequency between Linac – Ring, 10. 38 MHz corresponds to 49 buckets (96 ns) v We can select any buckets if we wait maximum of 5120 x 96 ns = ~500 ms EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 25
Super. KEKB Event / Timing Controls Beam Mode Pattern Generation Pulse 1 Beam Mode 1 Pulse 2 Beam Mode 2 Pulse 3 Beam Mode 3 Pulse n ……… Beam Mode n n+1 … Main event Preparation event codes for ‘n+1’ ‘n’ u Every pulse (every 20 ms) corresponds to a beam mode u 10 different beam modes are defined (for KEKB e+, etc) u One beam pulse may contain several event codes v. At least one main code and a preparation code for the next pulse u About 50 event codes are defined v. Some events correspond to many functions, and others to specific devices u Beam pattern buffer length (n) can be 2 to 500 (20 ms x 500 = 10 seconds) u A new pattern can be loaded at the end of the previous pattern v Otherwise, the pattern repeats forever. u Main events and preparation events in sequence v Main events trigger timing signals v Preparation events trigger software to exchange analog and delay parameters EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 26
Super. KEKB Event / Timing Controls Event Manipulation Human Operator Injection Programs Arbitrate and Generate Beam Mode Pattern (in Python. Tk) considering priorities of the rings equalizing pulsed power supply interval in 4 arrays (waveforms) of length 2 (40 ms) to 500 (10 s) 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 pattern generate 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. 27
Super. KEKB Event / Timing Controls Beam Mode Pattern Generators u Pattern panel arbitrates requests v From downstream rings with priorities, or human operators v There are several pattern rules due to pulse device features and limitations v Pattern arbitrator software was written in scripting languages to meet daily changes during the commissioning stage Remote controlled automatic pattern arbitrator Manual pattern generator v. Typical operation in 2009. ³~25 Hz for KEKB LER ³~12. 5 Hz for KEKB HER ³~0. 5 Hz for PF EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 28
Super. KEKB Event / Timing Controls Parameters u. Parameters switching via Event system v. LLRF phase/timing : 14 x 4 v. HP RF timing : ~60 v. Gun voltages, picosecond delay : 4 v. Pulsed magnets/solenoid : 14 v. Injection phase : 2 v. Bucket selection : 2 v. BPM : ~100 x 3 u. Basically sufficient for fast beam mode switching u. More parameters coming u. Integrity monitors u. Improved slow beam feedback, fast feedback, etc. EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 29
Super. KEKB Event / Timing Controls Linac Event System u. Satisfies the requirements v. Event rate : 114. 24 MHz (bit rate : ~2. 3 GHz) v. Fiducial rate : 50 Hz v. Timing jitter (Short term) : ~8 ps v. No. of defined events : ~50 v. No. of receiver stations : 17 v. No. of Fast parameters : ~130 v. CPU stopped 4 times since Sep. 2008 for 18 stations EPICS Collaboration Meeting / NSRRC CPU EVG EVR Opt. Fan-out EVR & LLRF Kazuro Furukawa, KEK, Jun. 2011. 30
Super. KEKB Event / Timing Controls LLRF u. LLRF Timing/analog signals are essential for absolute energy, energy spread, and dual-bunch energy equalization u. Signals are switched pulse-by-pulse u. Value changes are triggered by a preparation event u. Driver klystrons (SB), energy tuner klystron (KL), and sub-harmonic bunchers (SH) are managed by the event system EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 31
Super. KEKB Event / Timing Controls More Measurement Technique u. Switching between Four Rings v Challenging to improve beams during operation u. Event-based Controls may Help More v No-destructive measurements with four beams v Stealth (used beam-pulse) measurements ³ With beam deflector v Dithering pulse-by-pulse ³ If very good resolution was achieved EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 32
Super. KEKB Event / Timing Controls KEKB Operation Improvement (base of Super. KEKB) Belle/KEK May. 2000 Apr. 2003 Dual Bunch e+ Feb. 2005 Continuous Injections Dec. 2008 Crab Cavities and Simultaneous Injection EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 33
Super. KEKB Event / Timing Controls Top-up Beam Currents at Storage Rings u. Beam currents were kept v. KEKB 1 m. A (~0. 05%) v. PF 0. 05 m. A (~0. 01%) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 34
Super. KEKB Event / Timing Controls Towards Super. KEKB u. Nano-beam scheme at Super. KEKB v Requires low-emittance large current beams ³ Photo cathode RF gun for e- 7 Ge. V, 5 n. C ³ New capture section and new damping ring for e+ 4 Ge. V, 4 n. C ³ 40 times more luminosity v Design of damping ring ³ Selection of RF ³ Selection of harmonic number v Injection to PF-AR KEKB Super. KEKB e– e+ 8 Ge. V 3. 5 Ge. V 7 Ge. V 4 Ge. V 1 n. C 5 n. C 4 n. C 100 mm 20 mm 10 mm 2 bunch ³ Common BT to KEKB w PF-AR Injection needs 5 -10 minutes 2 bunch w Shorter life time of 10 min at Super. KEKB EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 35
Super. KEKB Event / Timing Controls Damping ring injection for Super. KEKB u Accommodate 2 bunches 2 pulses e− Gun KEKB ARC e+ BT (KEKB: 3. 5 Ge. V, 0. 6 n. C) Primary e– (4 Ge. V, 10 n. C) For e+ 25 Hz e– 25 Hz Inj. D. R. e+ 1 e– 2 e+ 3, 1 e+ Target Ext. e+ 1 e+ DR (1. 1 Ge. V, 4 n. C) e− Gun e– 4 e+ 3 e– 4 e+ 5, 3 e+ 3 e– 6 e+ 5 Super. KEKB e– 6 ARC EPICS Collaboration Meeting / NSRRC Primary e– (3. 5 Ge. V, 10 n. C) e+ BT (KEKB: 4 Ge. V, 4 n. C) e+ Target Kazuro Furukawa, KEK, Jun. 2011. 36
Super. KEKB Event / Timing Controls Development of EVR/PLC at SSRF u For Yokogawa FAM 3 PLC with F 3 RP 61 linux CPU u Prototype in 2010 u Production version at Oct. 2011 u Will simplify the additional stations EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 37
Super. KEKB Event / Timing Controls Super. KEKB timing software upgrade u Basically the same configuration as KEKB v Intelligent panels – pulse-by-pulse EVG Sequences – EVR PV databases u Need to upgrade to newer device driver/support with new register mapping v Under evaluation with newer firmware/EPICS support u Need more coordinated beam pattern generation v Need dependencies between pulses v Need to decide whether to change phases at DR u Need synchronization to laser rf gun v Laser based on local oscillator, need PLL and stabilization strategy u Possible more addition of event receivers to BT and Rings u Possible upward links for bucket selection data sharing u Linux-based device support for EVR/PLC from SSRF on F 3 RP 61 v Should be simple (? ) based on standard FAM 3 bus access EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 38
Super. KEKB Event / Timing Controls Summary u Simultaneous injections to three rings (KEKB HER/LER and PF) achieved u Challenging for four rings (incl. PF-AR) with a damping ring u Event-based controls : another layer of controls bellow EPICS slow controls u <http: //www-linac. kek. jp/cont/epics/event/> u There should be much room to establish further controls utilizing beam monitors, rf monitors, and more v With Phronesis (Ability to understand the universal truth, Greek word) we can enjoy our accelerator more EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 39
Super. KEKB Event / Timing Controls Thank You 谢谢您 EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 40
Super. KEKB Event / Timing Controls Thank you EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 41
Super. KEKB Event / Timing Controls Backup EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 42
Super. KEKB Event / Timing Controls Parameters u. Parameters switched via event system v. LLRF phase/timing : 14 x 4 ³Overall energy profile, dual-bunch energy equalization, final energy adjustment v. HP RF timing : ~60 ³Energy profile and backup management v. Gun voltages, picosecond delay : 4 ³Beam charge selection, dual bunch selection, bunching v. Pulsed magnets/solenoid : 14 ³Beam transport selection, orbit controls, positron focusing v. Injection phase interface : 2 v. Bucket selection interface : 2 v. BPM : ~100 x 3 u. Sufficient for fast beam mode switching u. Integrity monitors soon EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 43
Super. KEKB Event / Timing Controls Three Virtual Accelerators u Controls and instrumentations are essentially mode-dependent, and mutually independent u Selecting a real machine out of three virtual machines v Managing three parameter sets (four under Super. KEKB environment) e− Gun ARC e– BT (PF: 2. 5 Ge. V, 0. 1 n. C) PF Injection e+ Target Event-based Control System e− Gun ARC KEKB-LER Injection Primary e– (4 Ge. V, 10 n. C) e+ BT (KEKB: 3. 5 Ge. V, 0. 6 n. C) e+ Target e− Gun ARC KEKB-HER Injection e+ Target e– BT (KEKB: 8 Ge. V, 1. 2 n. C) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 44
Super. KEKB Event / Timing Controls Three-fold Independent Closed Loops u Feedback loop software act on one of three virtual machines v Managing independent parameter sets e− Gun ARC e– BT (PF: 2. 5 Ge. V, 0. 1 n. C) PF Injection e+ Target Event-based Control System e− Gun ARC KEKB-LER Injection Primary e– (4 Ge. V, 10 n. C) e+ BT (KEKB: 3. 5 Ge. V, 0. 6 n. C) e+ Target e− Gun ARC KEKB-HER Injection e+ Target e– BT (KEKB: 8 Ge. V, 1. 2 n. C) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 45
Super. KEKB Event / Timing Controls For Super. KEKB Complex u Slightly More Complicated Conditions with DR ³ Harmonic number of Super. KEKB-MR (509 MHz) is 5120 ³ Common frequency between Linac-MR is 10. 38 MHz (49 buckets, 96 ns) ³ DR should have common frequency, RF chosen to be 509 MHz ³ 2 x 2 bunches, bunch separation of 49 -bucket , kicker rise/fall time of 100 ns ³ Jitter (wait-time) of HP modulator (50 Hz) must be <~2 ms v Harmonic number of DR was chosen to be 230 u In order to Select All the Buckets in Super. KEKB MR v Active (Pulse-to-pulse) LLRF controls necessary at linac ³ Better LLRF monitor is required v Dependency between pulses increases u For PFAR Injection v Positron have to be used to share the beam-transport v Independent circumference controls will interfere w PF can use 2. 5 Ge. V electron with accidental synchronization (<~300 ps) ³ More investigation underway EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 46
Super. KEKB Event / Timing Controls Event System Consideration for Super. KEKB u. Possibly Cascaded Event Systems v. For damping ring, main ring and other sub-systems u. New firmware with new register map v. For newer device support software in EPICS community ³Several local modification already, want to synchronize with other institutes v. Several institutes in Asia may use Compact. PCI as well ³Whether PLC version can use the same environment? ? u. Several fast control projects for Super. KEKB v. Several embedded systems with PLC EVRs for RF stations v. Bucket selection to cover both damping and main rings ³In KEKB, separate system was used and selection signal was used as AC to EVG v. Fast feedbacks in Linac and in main ring u. Several others EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 47
Super. KEKB Event / Timing Controls BPM u. Tektronix DPO 7104 can acquire data at >50 Hz. v. With embedded EPICS u. Beam modes are recognized by events through CA network. u. Clients can monitor data of an interested beam mode. u 26 oscilloscopes are installed. u 100 BPMs are synchronized. (100 BPMs at BT as well soon) EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 48
Super. KEKB Event / Timing Controls Measurement and Data Acquisition u. Originally much efforts to develop detectors, shaping amplifiers v. No budget for all BPMs u. Switched to direct waveform acquisition v. Minimized active components, then minimized calibration tasks, maintenance v. Equal-length cables v. One oscilloscope covers about 5 BPMs, or combined 20 (or 40) waveforms v 5 - 10 Gs/s (with additional interpolation) v. Possible to measure dual bunches v. Solved many issues at once! v. Extract each signal, apply calibration factors, send to upper layer at 50 Hz EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 49
Super. KEKB Event / Timing Controls Embedded IOC on Oscilloscope u. DPO 7104, 10 Gs/s, 4 ch, 8 bit v. Windows-XP v. Cygwin software development environment v. Microsoft Visual C++ 2008 ³http: //www-linac. kek. jp/cont/epics/win 32/ v. EPICS 3. 14. 8. 2 v. Fast data-acquisition at ~150 Hz was tricky, but was possible v. Event triggers the data acquisition v. Beam positions and charges are calculated based on ~30 coefficients, and tagged with beam modes v 50 Hz processing is stable at Linac v. Very efficient for us EPICS Collaboration Meeting / NSRRC Kazuro Furukawa, KEK, Jun. 2011. 50
Скачать презентацию Super KEKB Event Timing Controls kazuro
5117f8ea43c8251f1031a53c63f94301.ppt