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Tevatron IPM status Oct 2009

Tevatron IPM status Oct 2009. Andreas Jansson K.Bowie, T.Fitzpatrick, R.Kwarciany, C.Lundberg, D.Slimmer, L.Valerio, J.Zagel. Also thanks to:

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Tevatron IPM status Oct 2009

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  1. Tevatron IPM status Oct 2009 Andreas Jansson K.Bowie, T.Fitzpatrick, R.Kwarciany, C.Lundberg, D.Slimmer, L.Valerio, J.Zagel Also thanks to: T.Anderson, M.Bowden, A.Bross, A. Chen, R.Dysert, S.McCormick, S. Suleimani, H.Nguyen, C.Rivetta, H.Glass, D.Harding, B.Hively, V. Kashikin, D.Miller, Z.Tang, J.Volk, T.Zimmermann, …

  2. Outline • Brief overview history of Tev IPMs • Summary of Review talk from 2007 • Long version available at: http://indico.fnal.gov/conferenceDisplay.py?confId=1272 • What happened then? • Progress reports from 2007 to now • Summary of partial reports given at Tev Dept & Vaia’s meetings • Current status IPM status October 2009

  3. Brief overview of IPM history DESIGN IPM status October 2009

  4. Goal GOAL: Measure protons and pbar beam size turn by turn at injection and ramp during normal operation to diagnose and mitigate emittance blow-up. IPM Review, September 21, 2007

  5. Two small beams separated by helix. Separate protons from pbars, injected from circulating beam Beam induced parasitic signals. Low vacuum pressure Fine granularity and many channels Single bunch resolution and gating Improved shielding and matched cables Local pressure bump with controlled leak Challenges in the Tevatron Solutions: Challenge: IPM Review, September 21, 2007

  6. IPM detector 9.9kV 10kV 0.2T 0V 1kV MCP 100V 0V All signal cables are enclosed in a Faraday cage! IPM Review, September 21, 2007

  7. Anode board and internal cabling • ¼ mm strip pitch • 200 channels (128 instrumented) • Board mounted series resistor for back-termination and LP filtering. • In-vacuum signal cabling using UHV-compatible flex-circuits • High resolution area can be moved by swapping connectors IPM Review, September 21, 2007

  8. Microchannel plate • Max gain with 36 proton bunches is ~1e4 to avoid saturation. • Can be achieved with single plate • With dual plates, each plate would run at a very low gain and low bias current. • Use single MCP with extra-high bias current. IPM Review, September 21, 2007

  9. Front end cabling • 40 channels in each vacuum DB50 feed-thru (flex circuit) • Transition board from feed-thru. • Mini-coax bundles with external shield. • Custom (CMS) DB coax connector in FE board. IPM Review, September 21, 2007

  10. DAQ system • CMS-QIE chip digitizes signal in tunnel. • Serial data uplink on optical fiber. • Receiver and data buffer in upstairs PC • Timing + QIE clock + QIE clock supplied from PC thru cat-5E cable Host PC (LabView) Data Buffer (2x 8 links) (PCI) Timing card (PCI) Service building Tunnel Timing fanout QIE cards (16x 8 ch) IPM Review, September 21, 2007

  11. QIE card • 8 channels (CMS QIE8) per board. • Achieved noise ~1.8fC with 4’ cable. • Data is combined with timing information, serialized by CERN GOL ASIC (rad hard) and sent thru optical fiber at 1.1Gbps data rate • Timing fanout board cleans up and distributes clock and timing signals IPM Review, September 21, 2007

  12. FE board input/output format OUTPUT (1.6Gbps serial link) 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 TX_EN/RX_DV QIE4 QIE3 QIE2 QIE1 QIE0 Timing bits QIE mode CAPID0 QIE7 QIE6 QIE5 QIE4 QIE4 QIE3 QIE2 QIE1 QIE0 Timing bits QIE mode CAPID1 QIE7 QIE6 QIE5 QIE4 QIE4 QIE3 QIE2 QIE1 QIE0 Timing bits QIE mode CAPID2 QIE7 QIE6 QIE5 QIE4 Error bits Proton Revolution Counter 2RF/7 Clock Counter INPUT (Cat5 cable) • 15MHz clock frequency • Proton and pbar revolution markers • Encoded signal: IPM Review, September 21, 2007

  13. Data buffer card • Handles 8 incoming optical links (64 channels, 1.1 GB/s of data) • Can sparsify data on–the-fly based on timing masks • 512MB RAM allows for • 20.000 turns of continuous data • 90.000 turns for 72 bunches • 6 million turns for a single bunch • Read out thru PCI64 bus. • Two boards are used to handle 128 channels. • Sync via jumper cable • IPM buffer board doubled as prototype for BTeV L1 data buffer. • Considered for use in MICE experiment. IPM Review, September 21, 2007

  14. 396 ns (21 buckets) p-pbar separation ~120ns RF 2/7 Timing card • Produces the 15MHz (2/7 RF) QIE clock • Decodes and transmits beamsync revolution marker + injection and trigger events • Controls QIE settings. IPM Review, September 21, 2007

  15. Labview Software IPM Review, September 21, 2007

  16. Installation timeline • Magnets installed shutdown ‘04 • Vertical detector installed Dec’05 • Arcing problems inhibited operation at full B field. High outgassing from retrofit retainer. • Vertical detector fixed, horizontal installed May’06 • reduced DAQ system with single buffer board due to power supply limits and firmware problems). • Full DAQ, larger leak installed Oct07 • 80 channels per plane, 2 buffer boards IPM status October 2009

  17. System Status 2007 NB. REAL DATA! • Both IPMs had ‘new’ software and firmware. • Vertical IPM works pretty well, basicall since installtion. • Horizontal IPM has some hardware problems (bad FE baord) that required an access. • Horz IPM also requires two buffer boards to measure beam size at injection IPM Review, September 21, 2007

  18. Beam size at IPM location By moving detector, able to fit beam in active area, except horizontal beam size at 150GeV IPM Review, September 21, 2007

  19. Brief overview of IPM history EARLY MEASUREMENTS IPM status October 2009

  20. Protons at low beta • Proton bunch #1 at low beta during store #4758. • Measured beam size 0.55mm, turn-by-turn variation (noise) 20µm. • Total signal per bunch ~1.3pC. 30 turn average single turn Magnet at 200A IPM Review, September 21, 2007

  21. Injection – Full B field Proton bunch #21 turn-by-turn RMS profile width 1.3 35 1.2 [mm] 1.1 1.0 0.9 turns 0 10 20 FFT 0 1 cm 0.0 0.5 1.0 Store #4772 Magnet at 200A IPM Review, September 21, 2007

  22. 100 turns Four injection measurements superimposed IPM Review, September 21, 2007

  23. Measured mismatch vectors • Nominal settings • Q701 at -22A • Q701 at -42A • Q711 at -25A • Need to increase Q711 by ~15A (saturation?) • Should result in 5-10% smaller vertical emittance • Should have very little effect on horizontal plane. • Should have been tested this morning… IPM Review, September 21, 2007

  24. Flying wire comparison Known electronics problem (cross talk from revolution marker pulse) Comparison of vertical beam size from IPM and nearby Flying Wire. Tuning of abort gap cleaner timing had caused blow-up of certain bunches. From MAD lattice file, expect a 13% wider beam at Flying Wire. See ~1%. IPM Review, September 21, 2007

  25. Pbars at 980 Gev Store #5172, Jan 07 Horizontal Vertical IPM Review, September 21, 2007

  26. Pbars at 150 GeV • Also saw coasting pbars (with vertical system) at injection • Requires moving the detector to pbar orbit. • Triggering did not work at first attempt (timing event found to be disabled). Fri Jan 12 2007, shot #5175 IPM Review, September 21, 2007

  27. Shot 5186 – vertical plane Two consecutive beam revolutions in Tevatron, just at injection of batch 9. IPM Review, September 21, 2007

  28. Vertical pbar injection data (batch 9) Beam position [mm] Beam size [mm] 0.6 3.2 0.5 2.8 0.4 0.3 2.4 0 10 0 10 • Beam position gives consistent oscillation ~0.2mm. • Need to look closer at beam size data, but… • There is a clear frequency component at twice the tune! IPM Review, September 21, 2007

  29. Brief overview of IPM history ISSUES IPM status October 2009

  30. Parasitic signals 1x1 store at 980GeV ~center anode strip • Despite very good shielding, beam related signals still present with MCP gain off. • Very stable from turn to turn -> reference subtraction possible • Present even on “broken” channels (where no ionization electrons are seen) Beam pulse Timing markers IPM Review, September 21, 2007

  31. Buffer board sync • With two boards, capacitive background appeared unaligned, and background subtraction didn’t work well • Found and fixed software data alignment bug • Verified that buffer board sync check works properly IPM Review, September 21, 2007

  32. PCI card poll glitching SERDES • Polling card via PCI during measurement was found to glitch the SERDES reciever. • “Solved” by using interrupt instead of polling, and reorganising code to minimize PCI traffic during acquisition. IPM Review, September 21, 2007

  33. What happened more recently? Integration IPM status October 2009

  34. IPM Review 2007 IPM Review Committee Report The charge to the committee has consists of the following two items: • 1. What is the current status of the Tevatron IPM systems - the front-end electronics and DAQ in particular? Identify any known problems or issues. • 2. Can the IPM system be made fully operational - complete detector readout with production electronics and DAQ issues resolved - by Jan 1, 2008? What additional resources ($$, effort) would be needed to meet that date? The committee was positively impressed with quality of the work and the part of the presentation devoted to the item 1. Nevertheless very little was said about the second half of the charge. It is unclear: • What does it mean “to make IPM system fully operational?” • Which additional resources, if any, are required to finish the project timely and which additional expenses are required? Taking the above into account the Committee suggests to convene an additional short session devoted to discussion of item 2 of the charge. Andreas should settle with the Tevatron department what they consider for the project to be operational and to present a clear answer to the part 2 of the charge. Having this session in about one or two weeks should leave enough time to elaborate details. IPM status October 2009

  35. Tev dept wish list Tevatron IPM Specs for Collider II Operation General Collider II IPM Specifications: • In General the IPM controls and data retrieval should be very similar to the flying wire front end. It should be able to perform the following: • Decode V:CLDRST state and setup the instrument based on a state to instrument spec mapping owned by the IPM front end. The TFW instrument has an example of this. • Should provide plane and particle sigma data on event $75 (profile timer) There are 35 profiles that currently go out up the ramp and through the lowbeta squeeze. • Should provide data to SDA. The instrument should own a “data ready” device similar to TFW that communicates the state of pending data. This can also be used for lumber jack Client Logging. • The instrument should be free running providing data during a collider store at ~ 1/30 min. (similar to TFW). • The instrument should write bunch by bunch data into ACNET array devices following the standard convention. • . The ACNET array devices that hold bunch by bunch information should be 37 elements long. • The enumeration of array devices should have the [0] element of the array as the average value of the 36 array members to follow. There may have to be some special code to handle updating the average to reflect and average of elements with non zero values. • The [1 – 36] would store the data where bunch 1 would correlate to [1] of the ACNET device respectively. • ACNET parameter representing data and setup should be placed in the lumberjack utilizing Client Logging. • The IPM should have an ACNET application that can perform the following functions (similar to T46 for TFW): • Standard user interface. • View and Configuration of State to IPM Spec Transition Map for pre-loading specs. • View and Configuration of IPM specs. • Ability to access and plot profile data correlated to data taken on profile event and periodic sampling with capability to have fitting options for plots. • IPM ACNET devices should attempt to follow a naming convention. IPM status October 2009

  36. ACNET control • Since early 2008 the Tevatron IPMs are state driven in much the same way as flying wires. • Selected output is logged when data ready since mid-January 2008 IPM status

  37. Tom’s ACNET interface Available summer 2008 (no plotting) IPM status

  38. PSPEC settings IPM status

  39. Pbar jacking Jan 31, 2008 Store #3874 IPM status October 2009

  40. Pbar jacking 2 Feb 1, 2008 Store #3876 IPM status October 2009

  41. IPM–FW comparison Jan 2008 IPM status

  42. How to improve data quality? • Fluctuations from measurement to measurement much bigger than turn-by-turn fluctuations for coasting beam. • One known source of bad data: synchronization problems! IPM status October 2009

  43. Example: Synchronized IPM status

  44. Example: Unsynchronized Easy to detect and reject by eye for manual data-taking! IPM status

  45. One manifestation of sync issues Histogram of proton counter in first buffer data frame. Expect single cluster of three bins around zero. Saw wider cluster + scatter + unexpected peaks IPM status

  46. Sync saga • We discovered relatively early on that PCI access during an acquisition would sometimes glitch one or more of the high-speed data links. • Appears to be a FPGA internal problem, now believe it is caused by does not like 5V input signals on pins close to high speed inputs. • Work-around: re-order setup sequence to limit access to board, use interrupt instead of polling. • Seemed to work fine. IPM status

  47. Board layout IPM status

  48. Sync saga cont’d • Even without PCI access during acquisitions, loss of synchronization still occurred relatively frequently, particularly for injection measurements (long wait time) • Improved the initial synchronization logic • Added firmware logic to allow links to resynchronize dynamically if needed, while waiting for a trigger (In original implementation, the entire chain was synchronized once by a timing card reset just before an acquisition) IPM status

  49. Sync saga cont’d • Early resync logic worked in test stand, but not in the Tevatron systems. • Used simulated TVBS in lab5 teststand. • At this point, FY08 omnibus budget came out, furloughs started and we lost Kwame (our FE board engineer) to Florida. • Rick (Buffer board engineer) took over debugging of both boards, and we moved the test stand to FCC (closer and real TVBS available). • Real TVBS available IPM status

  50. Sync saga cont’d • Found occasionally missing AA markers, and that FE board and buffer board treated this unspecified case differently. • Fixed with buffer firmware modification. • Also discovered “unexplained” PCI accesses during acquisition? • Don’t know where they come from, or how long they have been there (system patch?). • Tried to have board ignore PCI requests during acquisition, but this caused total PC lock-up. IPM status

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