Booster Fast Loss Monitoring PIP Booster Workshop R.J. Tesarek 11/23/15 1
Fast Loss Monitor Module Fast Loss Monitors: Module Schematic • sensitive to losses in single RF bucket (time resolved) 2nd Generation Module Design: • 2 PMTs and bases PMT 2 • Hamamatsu H1949 PMT 1 • typical gain 2.0e7 • each PMT views 1 scintillator each ~12mm thick • active area: 50.8mm x 152.4mm charged particle • counters plateaued (V thr = 30mV) to be efficient for MIPs through 1 scint. plate • assembly surrounded by 5mm thick FR-4 (G-10) Advantages: • can be sensitive to single minimum ionizing particle (MIP) • robust assembly (can be handled by gorilla) • less sensitive to activation products • very low noise rates (when PMTs in coincidence) ➡ probe of loss dynamics is a by-product of fast detection Disadvantages: • scintillator damaged by radiation (annual replacement?) Construction/Calibration details in beams-docDB 4993 11/23/15 R.J. Tesarek PIP Workshop 2
Module Installation (Collimators) installed 2/2015 5-3 5-4 Horizontal Target (5-1) Vertical Target (5-3) Absorber 6A Absorber 6B Absorber 7 installed 2/2015 Thanks to T.Johnson, D.Johnson, V.Kapin, K.Triplett, D. Dick 11/23/15 R.J. Tesarek 3 PIP Workshop
Booster Notching Region Notcher Short 12 (12-2) Absorber Notcher Absorber detectors 11/23/15 R.J. Tesarek 4 PIP Workshop
Booster Cycle Overview (3/11/15) PMT1 (downstream of 5-3) PMT3 (downstream of collimator 6B) Notch Cycle 10000 E_beam (MeV) Notch Injection Notch 9000 t ~ 400µs t = 0 t ~ 5,200µs 8000 E ~ 1,343 MeV E ~ 1,340 MeV E ~ 1,703 MeV 7000 T ~ 404 MeV T ~ 402 MeV T ~ 765 MeV 6000 Extraction P ~ 961 MeV/c P ~ 958 MeV/c P ~ 1,422 MeV/c t ~ 33,300µs 5000 E ~ 8,882 MeV 4000 T ~ 7,943 MeV 3000 P ~ 8,832 MeV/c 2000 1000 0 0 500 1000 1500 2000 2500 3000 3500 x 10 2 Time into cycle ( µ s) . 11/23/15 R.J. Tesarek 5 PIP Workshop
Features in Booster Cycles (3/11/15) 5,266µs into cycle (Notch @ 5.2ms) PMT1 downstream of 5-3 Losses persist in magnet for ~8-12µs (~4-6 revolutions) PMT3 Collimator 6B Losses persist in collimator for ~250µs Notch Cycle NB: clipline added on 3/18/15 11/23/15 R.J. Tesarek 6 PIP Workshop
Features in Booster Cycles (3/12/15) 400µs into cycle (Notch @ 400µs) PMT1 downstream of 5-3 Losses occur in same RF 1 revolution buckets on integer turns after the notcher fired PMT3 Collimator 6B All losses after 1 revolution notch formation Notch similar in character (not always in detail) Cycle NB: clipline added on 3/18/15 11/23/15 R.J. Tesarek 7 PIP Workshop
Scale of Fast Losses NB: data from 3/2/15 PMT1 downstream of 5-3 Dotted lines indicate 1st bucket approximate 1 bucket ~125 particles in the PMT signal (alone) counter PMT3 Collimator 6B Note: Different 1st bucket NOTCH timing Signals calibrated to ~90 particles in the (absent?) for this give ~2mV/MIP counter event Notch NB: clipline added on 3/18/15 11/23/15 R.J. Tesarek 8 PIP Workshop
PMT Signals 3/31/15 “Loss Event” Loss “event” PMT1 (downstream of 5-3) PMT3 (collimator 6B) Rev (RF/84 sync’d at notch) cycle note scale 11/23/15 R.J. Tesarek PIP Workshop 9
Booster Cycle Fast Losses 11/13/15 magnet 5-1 injection notch formation collimator 6A transition crossing collimator 6B collimator 7 extraction 1 Booster Cycle 11/23/15 R.J. Tesarek 10 PIP Workshop
Injection Fast Losses 11/13/15 start of injection magnet 5-1 2.2µs ORBMP collimator 6A revolution ramp down collimator 6B collimator 7 NOTE: Baselines shift indicates “DC” losses high losses with 1st protons 128 Booster Cycle Average 11/23/15 R.J. Tesarek 11 PIP Workshop
Module Readout and Gating Need quantitative information for tuning and studies • MADC analog system too slow • Use AD 333 100MHz scalers and discriminate PMT signals Instrumentation measures rates/booster cycle (independent of beam): clock: 38.768 kHz TTL s ( i ) − s ( i − 1) f CLK R ( i ) = INJ ( i ) − INJ ( i − 1) · temp compensated oscillator CLK ( i ) − CLK ( i − 1) • Rates average signals over period between $12 events (~1.33s), normalized per booster cycle • Use 333 scaler module for readout • Rates normalized by number of booster cycles • Clock: a periodic signal with a well known (stable) frequency. Because the booster RF is modulated it can’t be a clock signal. • Booster RF: Booster RF signal (logic level) to provide background rejection from non-prompt particles. Also counts “hits” for time-over-threshold discriminator. • Injection: Signal that beam may be injected into the booster (beam may not be present) • Gates: Time intervals of interest to measure rates in counter modules. To be fully defined, we need a starting time (in the booster cycle) and a duration. ➡ For instrumentation to be effective, we want to sample periods that are constant ( VERY similar) for every booster cycle. 11/23/15 R.J. Tesarek PIP Workshop 12
Fast Loss Rates in ACNET Gates before summer shutdown (instruments at 5-3 and 6B) Gate tmin tmax Comment 1 Inj Inj + 300µs injection losses* 2 Inj + 300µs Inj + 800µs losses around 400µs structure* 3 Notch Notch + 500µs losses around notch formation 4 Notch + 500µs Notch + 2800µs losses around notch formation (separated for timing) 5 Notch + 2800 BES losses in rest of booster cycle # Gates after summer shutdown (instruments at 5-1, 5-3, 6A, 6B, 7) Need discussion: • Current booster cycle has losses from different activities in cycle overlapping. • Limited number of gates/333 modules Candidates: • Injection • RF capture • Notching • Transition crossing • Extraction 11/23/15 R.J. Tesarek 13 PIP Workshop
Fast Loss Rates in ACNET Gate 1 I -> I+300µs A6B A6B Gate 2 I+300µs -> I+800µs 5-3 5-3 Notch at 5,200µs Data shown for time interval: Gate 3 3/31 17:00 thru 4/1 13:00 A6B N -> N+500µs Note: Rate = 0 when no notch present Correlation between some features observed at injection and features around notch 5-3 formation for these data. 11/23/15 R.J. Tesarek 14 PIP Workshop
Fast Loss Rates in ACNET A6B Gate 3 A6B N -> N+500µs Notch at 5,200µs Rate = 0 when no notch present 5-3 5-3 Gate 4 N+500 -> N+2,800µs Data shown for time interval: 3/31 17:00 thru 4/1 13:00 A6B Gate 5 N+2,800µs -> BES Note: Correlation between some band structure above correlated with 2 degree F features observed at injection variation in LLRF room temp and features around notch 5-3 formation and late in the cycle for these data. 11/23/15 R.J. Tesarek 15 PIP Workshop
Plans & Summary Plans (next few weeks) • Complete installation/commissioning of systems • notcher system (ready for ‘scope-permanent installation) • collimator system • determine gates for readout (collimator system) • cable readout for collimator system (expanded system over summer shutdown) ➡ expect system fully operational early Dec. Long term plans • autopsy counters exposed in booster for period 2/15 - 7/15 (radiation damage) • begin making detector replacements • explore rad-hard alternative to scintillator/PMT detectors (underway) New very fast loss instruments installed • single RF bucket resolution on losses • interesting data from ‘scope traces • rate measurements tested - yield interesting results • commissioning underway for collimator system Need catchy name for system 11/23/15 R.J. Tesarek PIP Workshop 16
Acknowledgements The following folks contributed time/resources (tools) an information used in this talk • C.Bhat • V.Kapin • W.Pellico • S.Chaurize • E.Hahn • T.Sullivan • R.Crouch • D.Johnson • M.Syphers • C.Drennen • T.Johnson • K.Triplett • D.Dick • C.Ornelas 11/23/15 R.J. Tesarek 17 PIP Workshop
Back Up Slides 18
Two Stage Collimation Target Target collimator Absorber Monitor collimator Absorber Monitor My Understanding: • Target disrupts beam halo • Absorber absorbs disrupted beam • Target/Absorber monitors “observe” target and absorber collimators ➡ Absorber should “shadow” target (absorber farther from beam core) 11/23/15 R.J. Tesarek 19 PIP Workshop
Module Placement 1 MIP Detection Threshold 10.000$ Considerations: • Observe particles from single RF bucket 1.000$ 10ns%Flight%Distance%(m)% • Low detection threshold (single MIP) 20 cm • Wide variation in beam kinetic energy 0.100$ e&$ (400 - 8000 MeV). mu&$ pi+$ K+$ ➡ Place detectors < 20cm from loss source p$ 0.010$ 0.001$ 1$ 10$ 100$ 1000$ Momentum%(MeV/c)% 11/23/15 R.J. Tesarek PIP Workshop 20
Module Calibration Physical Setup Understand individual detector response cosmic ray • PMT signal PMT 2 • Efficiency vs HV (given V thr ) PMT 1 • Pulse height vs HV PMT 4 PMT 3 • Dark rate (noise) vs HV PMT 6 Test Setup PMT 5 discr. (V thr = 30mv) Oscilloscope PMT 1 PMT 2 cosmic ray trigger PMT 3 Visual Scalers PMT 4 PMT 3 123456 PMT 5 PMT 4 123456 PMT 6 cosmic ray 123456 11/23/15 R.J. Tesarek PIP Workshop 21
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