Photon beam commissioning run plan Draft 28-Apr-97 D. Sober Equipment to be operational: Tagger detectors: 61 T counters, 384 E counters Scalers: T counters (gated and ungated) ROCs: T counters (incl. PS,PC,TA), E counters, Forward TOF Beam counter (old GWU plastic scintillator) Pair spectrometer Pair counter Total absorption shower counter Section of beam pipe with upstream beam pipe counters Collimator Start counter (temporary mounting) Forward TOF counters for Start Counter test Photofission scattering chamber (on cart for insertion) Abbreviations used in table: Scalers: B = beam scalers on Arne's EPICS screen T/DS = T-counters and Downstream counters Signals: BC = beam counter (GWU plastic scint.) BP = beampipe counters (US,DS,TD) PC = pair counter (Eric's 4-segment) PS = pair spectrometer StC = start counter TA = total absorption shower counter TC = T central counter (~T20 or T21) TOR = T-counter master OR Notes on column headings: "Photon rate" = R = rate in T1-T62 = 1E7 at (100 nA x 1E-6 X0) Rate in T1-T19 = 0.13 R Total rate (few MeV < k < E0) ~ 5 R T-HV = "OK" when all HV on and at normal setting Norm. = scaler to which other scalers will be normalized Signal to MCC = scaler on EPICS screen which MCC can be asked to hold within limits to keep rate constant Initial conditions: Collimator out T counter logic = TL.or.TR Photon DAQ DAQ Time T- Signal rate trig ROCs Scalers (hr) HV Norm. to MCC ---- ---- ------ ------- ---- -- ----- ------ ***Shift 1*** Accelerator beam tuning ***Shift 2*** beam centering n.a. - - B 2 OK BC BC harp scan n.a. - - B 0.1 PS magnetic field on T-counter HV scans -- also PS and PC (4 hr total) HV nominal (L) 1E6 - - T/DS 0.1 L* BC BC vary HV (L) 1E6 - - T/DS 9x0.1 L* BC BC Photon DAQ DAQ Time T- Signal rate trig ROCs Scalers (hr) HV Norm. to MCC ---- ---- ------ ------- ---- -- ----- ------ HV nominal (R) 1E6 - - T/DS 0.1 R* BC BC vary HV (R) 1E6 - - T/DS 9x0.1 R* BC BC ***Shift 3*** T-counter,PS,PC timing and E-counter HV (step all HV's) (4 hr total) vary TL,E HV 1E6 BC T,E - 5x0.3 L* BC BC vary TR,E HV 1E6 BC T,E - 5x0.3 R* BC BC ===RadPhi (4 hr)=== ***Shift 4*** Set best T HV for both L and R PMT's; switch logic to TL.and.TR (hall access) Analyze data for E HV's Analyze data for PS HV's Set PS HV to best provisional values Pair Spectrometer tests: Use both scalers and DAQ: Pair Spectrometer magnetic field tests (3 hr) PS field nom. 1E7 PS T,E T/DS 0.3 OK TOR TOR PS field 75% 1E7 PS T,E T/DS 0.3 OK TOR TOR PS field 50% 1E7 PS T,E T/DS 0.3 OK TOR TOR PS field 125% 1E7 PS T,E T/DS 0.3 OK TOR TOR Analyze: compare PS counter distributions with T counters Choose desired PS field. ===RadPhi (4 hr)=== ***Shift 5*** Pair spectrometer coincidence timing (variable delay box) (1 hr) Several delays 1E7 - - DS 5x0.1 OK PC TOR Final adjustment of PS, PC logic; scaler gating (hall access?) Test gating of scalers by PS (2 hr) 1E7 - - DS 0.3 OK PC TOR Pair counter commissioning: PS magnetic field off, converter in (for good rate in PC Veto counter) PC HV setting (2 hr) Take data for PC HV setting (analyze by requiring Veto hit) V fixed, PC vary 1E6 BC T T/DS 7x0.1 OK BC BC Take data for PC Veto HV setting V vary, PC fixed 1E6 BC T T/DS 7x0.1 OK BC BC Analyze data for PC + PC Veto HV's Pair counter coincidence timing (variable delay box) (1 hr) Several delays 1E7 - - DS 0.3 OK PS TOR Photon DAQ DAQ Time T- Signal rate trig ROCs Scalers (hr) HV Norm. to MCC ---- ---- ------ ------- ---- -- ----- ------ ***Shift 6*** Pair spectrometer field on Pair counter test vs. beam steering (2 hr) Move beam 1E7 - - DS 0.3 OK TOR TOR Final Pair Spectrometer HV setting (at final PS field) (2 hr) Vary PS HV's 1E7 - - T/DS 7x0.1 OK TOR TOR ===RadPhi (4 hr)=== ***Shift 7*** TASC gain matching (4 hr including 2 accesses) PS magnetic field off Put 1 cm Pb in beam ~10 m away, to produce broad spot of e+,e- (hall access) TASC HV-200 2E5 TOR T T/DS 0.1 OK TOR TOR TASC HV-100 2E5 TOR T T/DS 0.1 OK TOR TOR TASC HV nom 2E5 TOR T T/DS 0.1 OK TOR TOR TASC HV+100 2E5 TOR T T/DS 0.1 OK TOR TOR TASC HV+200 2E5 TOR T T/DS 0.1 OK TOR TOR Remove Pb from beam (hall access) Analysis: compare shapes of TDC spectra with rates over threshold PS magnetic field on Check TASC timing: TDC spectrum with 1 PMT on (1 hr) 2E5 TOR T T/DS 4x0.1 OK TOR TOR ***Shift 8*** Test normalization procedure: TASC vs PS vs Tagger (DAQ + scalers) (3 hr) Want 1E4 counts per T counter = 5E5 counts at 1kHz DAQ rate TASC trigger 2E5 TA T,E T/DS 0.3 OK PS PS PS tr.-low rate 2E5 PS T,E T/DS 0.3 OK PS PS PS tr.-hi rate 1E7 PS T,E T/DS 0.3 OK PS PS PS tr.-hi rate 5E7(?) PS T,E T/DS 0.3 OK PS PS Repeat cycle. ===RadPhi (4 hr)=== Photon DAQ DAQ Time T- Signal rate trig ROCs Scalers (hr) HV Norm. to MCC ---- ---- ------ ------- ---- -- ----- ------ ***Shift 9*** Install Start Counter and solid target (hall access) Check timing of Master OR, Start Counter, TOF at trigger supervisor (3 hr) Use variable delays; observe signals in Counting Room Possible hall access for major corrections. Take data with Start Counter and Forward TOF Start Counter tests (3 hr) vary StC HV 1E7 S*TOF T,E,TOF T/DS 4x0.5 OK PS PS ***Shift 10*** Continue Start Counter tests (3 hr) vary beam rates Vary S*TOF T,E,TOF T/DS 4x0.5 OK PS PS Remove solid target from Start Counter (hall access) Note that with no drift chambers, TOF are not necessarily seeing target. Target-out Start Counter tests (2 hr) vary StC HV 1E7 S*TOF T,E,TOF T/DS 4x0.1 OK PS PS ***Shift 11*** Tagger background rate measurements (2 hr total) Rad.out 100nA n.a. - - T/DS,B 0.1 OK clock ? Low rate 100nA 1E6 - - T/DS,B 0.1 OK clock TOR High rate 100nA 1E7 - - T/DS,B 0.1 OK clock TOR Rad.out 10nA n.a. - - T/DS,B 0.1 OK clock ? Low rate 10nA 1E6 - - T/DS,B 0.1 OK clock TOR Low rate 10nA 1E6 - - T/DS,B 0.1 OK TC TC Coll. in 10nA 1E6 - - T/DS,B 0.1 OK TC TC Coll.block 10nA 1E6 - - T/DS,B 0.1 OK TC TC For next 2 items, StC/TOF useful as background monitors, but not essential. Collimator alignment tests (3 hr) steer beam 1E7 S*TOF T,E,TOF B,T/DS 12x0.1 OK TC TC Test sweeping magnets (2 hr) vary currents 1E7 S*TOF T,E,TOF B,T/DS 12x0.1 OK TC TC ***Shift 12*** ===RadPhi (8 hr)=== Review tagger/beamline status ***Shifts 13-21 (Mon-Wed)*** Day+Eve: Contingency for tagger/beamline tasks Owl: RadPhi ***Shifts 22-24 (Thu)*** Install photofission scattering chamber (hall access) Photofission experiment tests RadPhi concurrent ***Shifts 25-27 (Fri)*** Photofission experiment tests (contingency) RadPhi concurrent ============================================================= Summary of scheduled shifts: Operations: Shift Day Time 1st half 2nd half ----- --- ---- ---------- -------- 1 Thu day beam tuning 2 eve beam steering; T-counter HV (scalers) 3 Fri owl T/E counter timing (DAQ) RadPhi 4 day Pair Spec. tests RadPhi 5 eve Pair Spec./Pair Counter 6 Sat owl Pair Counter/Pair Spec. RadPhi 7 day TASC tuneup 8 eve Normalization test RadPhi 9 Sun owl Start Counter/TOF 10 day Start Counter/TOF 11 eve Background/Collimator tests 12 Mon owl RadPhi.................................... 13 day TBA 14 eve TBA 15 Tue owl RadPhi.................................... 16 day TBA 17 eve TBA 18 Wed owl RadPhi.................................... 19 day TBA 20 eve TBA 21 Thu owl RadPhi.................................... 22 day Photofission test (install/run) 23 eve Photofission test 24 Fri owl Photofission test 25 day Photofission test (contingency) 26 eve Photofission test (contingency) 27 Sat owl Photofission test (contingency)