Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 1 KEK Linac Operation (Some Experiences) Kazuro Furukawa July 17, 2006 Mini Workshop on BEPCII Linac

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 2 Contents  In KEK Linac Commissioning  Tools to Test One’s Assumption/Hypothesis  Correlation Study  Tolerance Study, and How, Dependency on Parameters  Time-series Multi-parameter Analysis  Stability Feedback System as a Anomaly Detector  Resolving one Instability makes easy to Find Another  rf System  rf Monitoring  BPM Reading  Air-Conditioner On/off Operation and Direct Air-flow  Timing Jitter for Gun Against Sub-harmonic Bunchers  Direction of Gun Relative to Solenoids  Achromatic (Dispersion) and Isochronous (R56) Correction at J-ARC, Understanding Dispersion  Energy Spread Monitor, SOR, 8-Electrode, Wire-scanner  Archiving  Beam-switching and Virtual-machine Archiving  Achieved Energy/Orbit/Angle Stabilities  Cabling  Database Handling  Linac Tends to have Less Priority in Machine Studies  For BEPCII Linac Commissioning  Multi-bunch Operation  Sub-harmonic bunchers  Sinchronization  Difficulty of Asynchronous Multi-bunch Beam

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 3 Documents  Unofficial Incomplete Report on Linac Commissioning  In Japanese (sorry)   Slightly More Official Report  In NIM A 499., p167 

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 4 Items  Tools to Test One’s Assumption/Hypothesis  Simple Programming Tool is Necessary  Has Links to Machine Controls, Database, Archive, etc  Has GUI Capability  We cannot Handle Large Machine without a Help from Computer  Basic Tools  Save/Load Basic Parameter Sets  Active and Passive Correlation Plots  Calibration Tools for Instrumentations  Simple Stabilization Tools  etc.  SADscript, Python/Tk and Tcl/Tk are Used at KEKB/Linac

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 5  Correlation Study  Plotting Between Multiple Parameters  by Changing Certain Parameter Actively  by Observing Values During Beam Operation  Synchronous Data Acquisition Preferable  Fitting is Also Nice  May Find Correlation  May Optimize Parameters

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 6  Tolerance Study, and How, Dependency on Parameters  For example, (Single-) Parameter Tolerance to Keep 90% of Optimal Beam at Positron Target  By Scanning Parameters One by one  With Multi-Parameter Drifts, Much Tighter Limits  If a Certain Parameter is not at Optimal Value, The Tolerance of Another Parameter can be Much Smaller  Good Reference to Consider the Beam Stability

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 7  Time-series Multi-parameter Analysis  Often FFT or Correlation Analysis are not Powerful Enough to Represent  Time-series Data with Changing Frequency  Multi-parameter Dependencies  There Seem to be Several Methods  At Least It was Useful to Analyze Dependencies at Spring-8 between Power-line, Air- and Cooling-water Temperature, and Beam  Singular Value Decomposition (SVD) Analysis  Can be Used to Find Correlation  For Example  If we Find 5 Good Singular Values For 10 BPM Values Starting from Gun, The Source of Fluctuation may be at the 6th BPM  Down-hill Simplex  Somewhat Brute-force, but …

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 8  Stability Feedback System as an Anomaly Detector, etc  Feedback Tool is a Source of Valuable Information  Feedback Signal can be an Anomaly Detector  If We scan a Certain Parameter, we want Another Parameter Stable to Continue the Beam Study  Even If We are satisfied with a Certain Parameter, It is Still Good to have Feedback for Above Purpose  Resolving one Instability May often Reveals Another  Step-by-step Resolution !!!

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 9  Understanding of Our Own System  rf System  Still Most Important to Our System  rf Monitoring  Monitors Down to 0.05 Degree in Phase, 0.02 Percent in Amplitude  Keeps 0.1degree and 0.1 Percent  BPM Reading  Every Beam Pulse, Synchronous Reading, Resolution  Air-Conditioner On/off Operation and Direct Air-flow  Timing Jitter for Gun Against Sub-harmonic Bunchers  Direction of Gun Relative to Solenoids

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 10  Achromatic (Dispersion) and Isochronous Correction at J- ARC  Synchronous Measurement with Many BPM and Streak Camera  Dispersion (R16, R36) and Second Order (R166, R366) Correction  Then Isochronicity (R56) Correction  Understanding Dispersion Effect to Beam Stability

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 11  Achieved Energy/Orbit/Angle Stabilities  Energy 0.03% (rms), …  Energy Spread Monitor, SOR, 8-Electrode, Wire- scanner  Archiving  Beam-switching and Virtual-machine Archiving  Cabling  Database Handling  Linac Tends to have Less Priority in Machine Studies

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 12

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 13 Increase of the Luminosity May.2000 Apr.2003 Dual Bunch e + Feb.2005 Continuous Injections KEKB and Linac Accelerator

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 14 For BEPCII Linac Commissioning  Multi-bunch Operation  Sub-harmonic bunchers  Sinchronization  Difficulty of Asynchronous Multi-bunch Beam

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 15 KEKB Commissioning Groups  Formation of Commissioning Group (KCG)  Linac Commissioning (LCG)  7 from Linac  ~10 from Ring  KEKB Ring Commissioning Group (KCG)  All LCG  ~20 from Ring  Several from Detector (BCG)  Commissioning software base was formed during Linac Commissioning (1997~) Tcl/Tk, SAD/Tk, Python/Tk LinacKEKB Ring KEKB Commissioning Group Linac Commissioning Group KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 16 SADScript  Mathematica-like Language  Not Real Symbolic Manipulation (Fast)  EPICS CA (Synchronous and Asynchronous) CaRead/CaWrite[ ], CaMonitor[ ], etc.  (Oracle Database)  Tk Widget  Canvas Draw and Plot  KBFrame on top of Tk  Data Processing (Fit, FFT, …)  Inter-Process Communication (Exec, Pipe, etc) System[ ], OpenRead/Write[ ], BidirectionalPipe[ ], etc.  Greek Letter  Full Accelerator Modeling Capability  Also Used for non-Accelerator Applications KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 17 SADScript  Example FFS; w=KBMainFrame["w1",fm,Title->"t1"]; $DisplayFunction=CanvasDrawer; W1=Frame[fm]; c1=Canvas[w1,Width->600,Height->400, Side->"top"]; Canvas$Widget=c1; data = {{0,0}, {1,1}, {2,5}, {3,8}, {4,10}, {5,7}, {6,4}, {7,2}, {8,0}, {9,2}} fit = FitPlot[data,a Sin[x b + c] + d, x, {a,5},{b,1},{c,1},{d,5}, FrameLabel->{"X","Y"}]; phase = StringJoin["Phase : ", (c/.fit[[1]]) 180/Pi, " Deg."]; f1=KBFComponentFrame[w1,Add->{KBFText[Text->phase]}]; TkWait[]; Exit[]; KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 18 KEKB Alarm Panel  KEKB Alarm Main Panel covers Linac Alarms as well. ~10,000 Records are Monitored in One Panel. Detailed alarm information/history is available in a separate panel Linac Ring KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 19 Beam Optics Panels in SAD  Beam Optics Matching and Optimization Panels in SADscript  Some Parameters goes thru EPICS Gateways, others directly to Linac KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 20 KEKB Operation Panel Examples  Tune Measurement and Tune Changer KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 21 Virtual Accelerator in KEKB  Tune/Optics Server  Keep A Model of Real Accelerator  Can Change Tune, Chromaticity, etc, on Request by Other Panels  Act as a Virtual Accelerator KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 22 Example Virtual Accelerator  Virtual Accelerator may Provide the Both Fake Steerings and Fake BPMs Maybe with Simulated Errors/Noises  Orbit Correction Application may Work On Those Fake Information Operation Panel Orbit Correction Real Acc. Optics Steerings BPMs Noises Virtual Acc. Optics Steerings BPMs Errors KEKB and Linac Operation

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 23 Thank you

Kazuro Furukawa, KEK, Jul KEK Linac Operation and Stability Linac Mini-Workshop 2006, IHEP, Beijing 24