BPM Upgrade Projects Status & Technical Update Bob Webber DOE Review of Tevatron Operations March 2005

BPM Projects - DoE Tevatron Operations Review - March Webber2 Recent and Active BPM Projects  Recycler Ring  Completed and operational since early 2004  NuMI Beam Line  Completed and operational since first NuMI extracted beam  This system reported meaningful beam position data on first pulse !!!  Tevatron Ring ( ) (9/2/03 – 5/17/05) ($1081K labor, $1764K m&s)  Installed and operational for routine proton measurements in ~25% of the ring; functioning compatibly with remaining old systems  Completion of installation scheduled by end of May 2005  Antiproton Transfer Lines ( ) (3/26/04 – 7/25/05) ($91K labor, $284K m&s) (details in Elvin Harms’ Rapid Transfer Talk earlier this breakout)  In final design stage, manpower assigned, ~80% procurements done  Will employ NuMI/Recycler software and Tevatron EchoTek boards  Completion expected by ~August ’05  Main Injector Ring ( ) (1/3/05 – 6/1/06) ($324K labor, $900K m&s)  Requirements being reviewed  Awaits manpower currently devoted to Tevatron and Transfer Line projects  All systems are built around a common commercial (Echotek) digital receiver board

BPM Projects - DoE Tevatron Operations Review - March Webber3 Tev BPM - General Status  Cooperative activity between Computing and Accelerator Divisions, CD has provided ~80% of total project effort  Essentially all hardware is in hand, including spares  Considerable planning and care allow adiabatic installation without adversely impacting Tevatron operations  It is a big deal to seamlessly replace a large operational system without disrupting Collider operation and luminousity production  7 of 27 systems are installed and routinely operational for proton measurements (functional replacement for old systems)  Antiproton position measurements have been demonstrated but not yet routinely operational  Installation pace is presently limited ~equally by:  Opportunity -- we don’t install during a Collider store  Debugging –- operational problems must be solved as they are discovered

BPM Projects - DoE Tevatron Operations Review - March Webber4 TeV BPM - Software  ~85% of required VME front-end software functionality has been implemented and debugged  Data is packaged, either in VME front-end or in ACNET BPMLIB library code, to “look like” data from the old BPM system so as to minimize modifications to legacy console applications  Software switch permits transparent operation with mixture of old and new BPM systems in field  Critical legacy console applications are working with new BPM data after little or no modification  Some new applications are being developed to take advantage of the system’s new capabilities  SDA is being updated to use the new BPM data as each new crate is installed

BPM Projects - DoE Tevatron Operations Review - March Webber5 TeV BPM - Colored Pictures! A3 House Installation BPM Integrity Check

BPM Projects - DoE Tevatron Operations Review - March Webber6 TeV BPM – 36 Bunch Closed Orbit Resolution Upper Limits 20 minutes of closed orbit data for A3 BPMs 400 microns full vertical scale all plots Histograms of same data and RMS variation from the mean

BPM Projects - DoE Tevatron Operations Review - March Webber7 TeV BPM – 36 Bunch Closed Orbit Resolution Correlation plot of closed orbit data from two BPMs on opposite sides of ring estimate resolution to be ~5 microns

BPM Projects - DoE Tevatron Operations Review - March Webber8 Tev BPM – Single Proton Bunch TBT Measurements TBT resolution is better than 50 microns RMS

BPM Projects - DoE Tevatron Operations Review - March Webber9 TeV BPM - Antiproton Measurement “Plan A”  Establish cross-talk (imperfect pickup directionality) coefficients a, b, c and d and compute corrected antiproton signals according to:  Now working to establish unique coefficients for each BPM and cope with operational maintenance of time varying values  There is a “Plan B” … BPM ApAp ProtonsPbars A pbar B pbar BpBp

BPM Projects - DoE Tevatron Operations Review - March Webber10 TeV BPM – Antiproton Measurements Proton sum signal Proton position Pbar positionPbar sum signal Pbar sum signal during proton loading (ideally zero) Proton loading Pbar loading Ramp

BPM Projects - DoE Tevatron Operations Review - March Webber11 TeV BPM - What’s Left  Solve currently known bugs  Intermittent first turn/injection turn-by-turn (phase/timing problem)  Complete hardware installation  Implement and test additional required functionality  Robustness of Pbar measurements  “Safe” mode (timing robust first turn measurements)  Calibration-scaling-offset database  Produce as-built drawings and documentation  MOU -> operations  Project closeout

BPM Projects - DoE Tevatron Operations Review - March Webber12 Transfer Line BPM  First system required to observe both 53MHz and 2.5MHz beam structures  Major impact on design and required dynamic range of analog circuitry upstream of digital receiver boards  Precursor to MI BPM system with similar requirement  Operational scenarios are complicated due to different beam structures down parts of beam lines at different times  Recycler/NuMI front-end software that is suited mode switching and cycle dependent data buffers will be used  Design of analog circuit is in final prototype stage  All major procurements except analog boards are complete  VME front-end software is ready and waiting  Prototype/development system now installed at F23  Schedule calls for completion mid to late summer 2005 – integration will be subject to operational constraints

BPM Projects - DoE Tevatron Operations Review - March Webber13 Main Injector BPM Project  This project will follow on the heels of the currently Tevatron and Transfer Line BPMs  Scope  Replace signal processing electronics and front-end data acquisition systems for ~208 beam position monitors located around the Main Injector and in six buildings  Objectives  Eliminate obsolete Multibus II hardware and ACNET communications protocol  Accommodate measurement of beam in 2.5MHz RF buckets  Provide improved measurement resolution  Beams Document #471, dated February 2003, specifies system requirements and is now under review by Main Injector Department

BPM Projects - DoE Tevatron Operations Review - March Webber14 Main Injector BPM - Similarities to Tevatron BPM  General system design and implementation  Beam information to be obtained and types of measurements, i.e. first turn, closed orbit, and turn-by-turn  Anticipated hardware, except more complicated analog circuitry upstream of digitizer  Scope of DAQ, on-line, and off-line software, although different in detail

BPM Projects - DoE Tevatron Operations Review - March Webber15 Main Injector BPM - Differences from Tev -- All in the Details  Main Injector operating cycles are more varied in type than in Tevatron and dynamically interwoven in time  Both 2.5MHz and 53MHz signal frequencies must be processed (in different Nyquist bands)  Measurement data for multiple operating cycle types is to be stored separately in parallel front-end data buffers  Both protons and antiprotons must be measured, but  Do not circulate simultaneously (but fine timing is different)  Pickups are not directional not separate p/pbar cables protons and pbars require different fine timing  Measurement of user selectable segment (batch) of the circulating beam is required

BPM Projects - DoE Tevatron Operations Review - March Webber16 Main Injector BPM - Anticipated Implementation  Analog front-end electronics will leverage heavily off Transfer Line BPM project (common requirement to deal with 2.5MHz and 53MHz signal frequencies)  VME and VXWORKS front-end DAQ systems as other new systems  Tevatron style EchoTek digital receiver boards  Tevatron style digitizer clock and timing boards  Front-end software probably dependent on what group implements the system (different in detail from both Tevatron and Recycler)

BPM Projects - DoE Tevatron Operations Review - March Webber17 Main Injector BPM - How Project Likely Plays Out  Little dedicated effort up to now other than clarification and refinement of requirements  MI department occupied with NuMI commissioning  BPM people occupied with the other new BPM systems  Analog front-end design will flow from Transfer Line project  Most people who provided engineering, software, and technical support for NuMI BPM will focus on Transfer Line project through ~May ’05  Software support from Tevatron project might become available in ~June ’05  Commodity procurements can begin any time (EchoTek boards already procured and in hand)  A development system initially with either Tevatron or Recycler software should be installed in MI by June 2005  Computing Division will likely play a major role in the project

BPM Projects - DoE Tevatron Operations Review - March Webber18 BPM Projects - Summary  We are mid-stream in the effort of re-building all major BPM systems in the accelerator complex except Linac and Booster  Results from completed systems in Recycler and NuMI and partially installed systems in Tevatron show excellent performance and operational credibility and utility  Considerable effort remains to:  Complete Tevatron system  Overcome analog signal challenges for Transfer Lines and Main Injector  Meet the diverse and dynamic functional requirements demanded in Main Injector

BPM Projects - DoE Tevatron Operations Review - March Webber19 BACKUP SLIDES  #1577 B3 resolutions  1571 coupling  1581 pbars  #1752 for Rob’s most recent very good talk

BPM Projects - DoE Tevatron Operations Review - March Webber20 Antiproton Measurements  Present ratio of proton to antiproton intensities combined with directivity of stripline pick-up produces residual proton signals at the antiproton port about 50% the amplitude of antiproton signals  When antiproton intensities increase they will begin to “contaminate” the proton signals also  We opt to not pursue p/pbar separation by precise timing Typical signal from pbar end of BPM for present bunch intensities 80 nsec/tic Pbar bunch signal Undesired Proton bunch signal

BPM Projects - DoE Tevatron Operations Review - March Webber21  Separate p/pbar signals with relaxed timing requiring precision and maintenance of ~50 nsec rather than ~5 nsec  Observe only “isolated” proton or antiproton bunches at ends of 12-bunch trains  No pbar bunches observable One pbar bunch observable  Five bunches observable Two bunches observable Antiproton “Plan B”

BPM Projects - DoE Tevatron Operations Review - March Webber22 Coverage of Ring in Antiproton “Plan B”  Locations with at least one clear pbar bunch (at least 400 nsec from nearest proton bunch) at various times in cycle  x axis is feet around ring from B0, each point is BPM location  y axis is clearance >21 is “clear”

BPM Projects - DoE Tevatron Operations Review - March Webber23 HA15 and VA14 P/Pbar Positions “Plan B” Changing Separators Horizontal Pbar Horizontal Proton Vertical Proton Vertical Pbar Position Scales 2mm/box

BPM Projects - DoE Tevatron Operations Review - March Webber24 Horizontal A15 Helix Change and Pbar Loss “Plan B”

BPM Projects - DoE Tevatron Operations Review - March Webber25 Block Diagram Cartoon of Signal Path  Note that proton and pbar signal paths from same half of BPM are directly connected together by the stripline --- reflections from one will feed directly into the signal of the other attenuator53MHz BPF Eight Channel VME Digital Receiver Proton Inside attenuator53MHz BPF attenuator53MHz BPF Proton Outside Pbar Outside attenuator53MHz BPF Pbar Inside VME CPU ACNET Diagnostic and Calibrate Signals

BPM Projects - DoE Tevatron Operations Review - March Webber26 Main Injector BPM - Possible Roles for Computing Division  Total effort level would be between that provided for Recycler and Tevatron BPM Projects Less engineering design effort than in Tevatron project  Administrative project management  Analog circuit board layout and fabrication based on AD designs  Support for procurement, incoming component inspections and testing, production testing, equipment tracking, etc.  Supply Tevatron BPM style timing boards  DAQ, on-line, and off-line software components after successful completion of Tevatron system  Installation manpower  To serve all these roles, CD effort estimated as on the scale of 60 FTE months  Learning curve (AD language, machine operational issues, ACNET) has already been largely traveled by CD personnel on Tevatron project  Details will be different

BPM Projects - DoE Tevatron Operations Review - March Webber27 BPM Accuracy/Resolution Specs This is Table 2 from Requirements document. Table gives the most stringent requirements on the system; for certain types of operation these requirements are relaxed. Note: resolutions are stated as 3 sigma. Key Specifications (Protons): Measurement Range:  15mm Absolute Position Accuracy: < 1.0 mm Long Term Position Stability: < 0.02 mm Best Orbit Position Resolution: < 0.02mm (0.3 sec averaging) Position Linearity: < 1.5% Relative Position Accuracy: < 5% Intensity Stability: < 2% Key Specifications (Pbars)_: Measurement Range:  15mm Absolute Position Accuracy: < 1.0 mm Long Term Position Stability: < 0.02 mm Best Orbit Position Resolution: < 0.05mm (0.3 sec averaging) Position Linearity: < 1.5% Relative Position Accuracy: < 5% Intensity Stability: < 2%

BPM Projects - DoE Tevatron Operations Review - March Webber28 Demonstrated Beam Measurements  Recycler-type BPM front-end is set up for development and tests in TeV House A1  Connects to both Proton and Pbar signals of one horizontal BPM and one vertical BPM  Interfaced to ACNET with small subset of ultimate required functionality  Closed orbit and turn-by-turn measurement performance have been demonstrated  In use to assess narrowband frequency domain p/pbar signal de-convolution  Will soon demonstrate “wide” time separation of Protons and Pbars (utilize isolated bunches at the ends of the otherwise over-lapping 12-bunch trains); ~50 rather than ~5 nsec timing

BPM Projects - DoE Tevatron Operations Review - March Webber29 Proton Positions in Load of Store #3172: Old vs New Old: rms error ~140 um for uncoalesced beam, ~70 um for coalesced beam, and 0.6 mm “step” between the two New: rms error ~25 um for uncoalesced beam, <9 um for coalesced beam, no “step” between the two

BPM Projects - DoE Tevatron Operations Review - March Webber30 Closed Orbit Resolution During Proton Loading Green: Vertical 100 microns/div showing ~10 micron resolution and orbit changes due to leakage fields in ramping injection Lambertson magnet Red: Beam Intensity showing proton bunches loading Yellow: Time in Supercycle

BPM Projects - DoE Tevatron Operations Review - March Webber31 Upper Limit of Closed Orbit Resolution Average of standard deviations for twelve five-minute intervals First one-hour intervalSecond one-hour interval ± mm ± mm Two one-hour periods of 1 KHz bandwidth proton position measurement data, 17 hours apart, in store #3148. (data-logged at 1 Hz) 50 microns / vertical division Demonstrates upper limit resolution of 9 microns rms in 1 Khz (any real beam motion not excluded) to meet spec of 7 micron 1 sigma in ~10Hz

BPM Projects - DoE Tevatron Operations Review - March Webber32 Injection Turn-By-Turn --- Un-coalesced Protons Vertical A14Horizontal A15 vertical axis units are millimeters in all plots vertical tune horizontal tune

BPM Projects - DoE Tevatron Operations Review - March Webber33 Turn-by-Turn Long After Injection Single Coalesced Bunch Vertical A14Horizontal A15 vertical axis units are millimeters in all plots Horizontal transverse motion due to persistent synchrotron oscillation

BPM Projects - DoE Tevatron Operations Review - March Webber34 Upper Limits on TBT Resolution --- Vertical A14 If remove betatron and synchrotron motion by zeroing 17 frequency line amplitudes around betatron frequencies and one at synchrotron frequency, leaving untouched 494 of the original 512 frequencies, TBT resolution is found to be 15 microns Standard deviation of raw data is 34 microns

BPM Projects - DoE Tevatron Operations Review - March Webber35 Same Coalesced Proton Bunch Given Big Vertical Kick Vertical A14Horizontal A15 vertical tune horizontal tune vertical tune

BPM Projects - DoE Tevatron Operations Review - March Webber36 Antiproton “Plan A”  Model BPM as an 8-port network at processing frequency  Measure network transfer functions with beam, e.g. ratio of proton signal on pbar end to proton signal on proton end  Measure signals then correct according to pre-determined transfer function before computing positions  Measurements in process to determine achievable accuracy Linear System P Upper In P Lower In Pbar Upper In P Upper Scope InRefl InRefl InRefl InRefl Pbar Upper Scope P Lower Scope Pbar Lower Scope BPM ApAp ProtonsPbars A pbar B pbar BpBp