Notes - Instrumentation/beam physics meeting - Dec 8, 2004 reports on re-commissioning instrumentation Agenda: A. MI BEAM changes - quick averaging and MI Beam Energy loss B. FBIs - Tom Meyer C. Synclite - Randy D. Tev Flying wires - Nathan Eddy E. BLTs F. SBDs G. What devices to use for intensities? Action Items: 1. General algorithm for running averages 2. MI quick averaging and beam energy loss - more discussion with MI people and experience with these devices. 3. MI FBI timing adjustments 4. synclite - get it operational 5. Flying wires - move from functional to operational 6. Abort gap monitor - verify gating w/r to kicker and calibrate. 7. MI SBD - get 2.5 mhz going 8. Tev SBD - see list below in details 9. MI BMP BLT - finish debugging and commissioning. Details: A. Quick averaging and MI Beam energy loss devices. Tom Meyer added beam energy loss calculations to the MI IBEAM( DCCT) front end. His slide is reproduced below. There were a lot of questions about the algorithms. This will get worked out between Tom and the MI people. B. MI and Tev FBIs 1. MI - no changes - but needed to have timing adjustments for the pbars - done Monday Dec 13, 2004 2. Tev a) operational b) New wall current monitor arrangement - doc 1475 c) new ACNET devices C:FBITNG = C:FBIPNG + C:FBIANG C:FBITWG = C:FBIPWG + C:FBIAWG C:FBIRST – allows remote reset C:FBISET = changes to FBI are not written to file unless this is 1 d) store by store check of SBD and FBI intensity calibration with respect to DCCT C. Synclite - Randy reported that this is not yet operational - goal is christmas. He is testing for systematic effects and trying to use filters to get a dispersion measurement. Abort Gap monitor - 1. Operational 2. Timing needed to be adjusted 3. Is the gate really correct relative to kicker rise? (not looking till 5 buckets after last bunch) 4. Would like to check the calibration with different intensity proton bunches. D. Flying wires - Nathan Eddy 1. Functional 2. Pbar timing needs to be checked (done) 3. 7 micron wires work! 4. New lattice numbers in FE 5. Want to test effect on expts of 7 micron wires during HEP (done) Flying wire emittance OAC 1. Three calculations a. Flying wire only, dp/p from FWs b. Uncoupled, dp/p from SBD rms and Mike Church(MC) formulas c. Coupled, with dp/p from SBD rms and MC formulas 2. All use current lattice parameters 3. dp/p on ramp will be either interpolation of MC or Gaussian approximation 4. Schedule – by Christmas 5. Once operational, no emittance calculation in FW FE E. BLTs- Vic Scarpine 1. MI Stripline - operational despite analysis bug 2. MI BMP BLT - debuggina dn timing system - will ask for magnet remapping after commissioning. 3. TEV scope BLT - operational 4. Tev Struck BLT - operational F. Tev SBD 1. Operational a. Bunch centroids timing +/-40 pS b. Difference p/pbar timing +/- 10 ps 2. No online emittance and dp/p numbers, but “soon” using Alvin’s unconstrained fit 3. Archive viewer for saved raw data 4. MCR Viewer – display version available 5. Offline OAC to get ultimate phase space distributions using unconstrained fit – January? 6. Other planned improvements a) Squelch for zero intensity bunches - done (The moment calculations went bonkers when the beam went away. Now, the beam intensity must average more than 6 times the RMS noise floor across the bucket before the moments are calculated. Zero beam noise virtually never triggers calculation, but even the slightest beam in just one bucket will cause the moments to be calculated for that bucket. b) Saving of distributions at 150, up the ramp also at flattop before HEP, maybe even every step in the squeeze. This could be either a "doorbell" and/or listening to cliock events. ( a doorbell has been implemented such that if you c) need to resurrect ACNet control device that allowed logging during HEP? d) b) and C) have been done - setting T:SBDACC = N causes N writes of the raw data, separated by 10 seconds, Each write T:SBDACC is decremented until it gets to 0 inw which case the writing stops. 7. Priorities for SBD work 1) squelch - done 2) doorbell - done 3) MI 2.5 mhz 4) dp/p and emittance in FE using matrix method G. Other discussions 1. Use SBD or FBI for Intensities in the super- and mini-tables? a) there is no need to be consistent between MI and Tev as the machine to machine calibrations aren't known very well. b) Stephen believes the SBD is better( more stable, fewer fluctuations) in the Tev but that needs to be tested since the end of the shutdown. 2. Running averages. Valeri brought up that we need more running averages so that SDA data is less noisy, and people don't need to make their over averages with D44 data. Val suggested and algorithm in whcih a new average is started when a reading is more than 10 sigma different from the current average. ------------------------------------------------------------- Tom Meyer's Slide - Overview of MIBEAM Front end changes ----------------- Quick Averaging: This averages starting when beam crosses a given threshold and then increases the averaging until the given weight is achieved. The averaging algorithm is the same as the Running Average. The devices for Quick Averaging are as follows: I:QABEAM the measurement. I:QALBS the weighting, not settable via the ACNet console. Beam Energy Loss: This measures the beam lost during the cycle, then multiplies it by the energy in the ring at the time of loss. This process runs at 720Hz. The calculations for the \ process can be seen below. Beam Difference = bd = beam(n) – beam(n-1). Beam Energy Loss = bel = bd*Energy(MDAT) * 1.6*10-1(kJoules/1012GeVp) There are many different devices associated with this measurement. The following is a synopsis of those devices. I:BEL This device shows the sum of beam energy lost since the start of the last MI event. Its value is held constant from the end of ramp until the beginning of the next MI event. I:BELOST This device is the raw readback of beam energy loss in the Main Injector. It is produced at 720Hz and is not held at any event. I:BELTOT This device is the sum of I:BEL over all MI events. It integrates continuously and maintains its value during MIBEAM reboots. I:BEL5MA This device is a 5 minute average of beam energy lost. It is simply the difference of I:BELTOT over 5 minutes divided by 300 seconds. I:BEL1HA This device is a 1 hour average of beam energy lost. It works the same way as the 5 minute average. I:BEL1HT This is simply the difference of I:BELTOT over the previous hour. I:BEAMET This device is the total extracted beam energy. It is taken when I:BELTOT is measured and so updates at the end of each cycle. I:BELRMP This is a measurement of the MI energy via MDAT. It is used for diagnostics. I:BEAMDF This is the raw beam difference measurement. Also used for diagnostics. I:BELXX where XX is the MI reset event. This is the last measurement of I:BEL at the end of the given cycle. For example I:BEL29 is the sum of beam energy lost during the last $29 event. This value is held until the beginning of the next $29 event. Things still left to be done: Time in all I:BELXX devices. Check BEL measurements vs. expected intensity losses. Timing on the I:BELXX devices needs to be automated. Whatever else is needed.