Dear hallC2003 collaborators, Here a first draft of a calibration runplan. Please look at it and send your comments to me at henkb@nikhef.nl I hope we can discuss it with at least some of you when I will be at Jlab (July 5-16, but 8-11 I will be busy with the PAC) With best wishes, Henk Blok (OPTICS) CALIBRATIONS, Spring 2003 ----------------------------------- version 0.0, 20/6/2002 General remarks. ---------------- F2: standard use of HMS; only normal elastic calibrations at some angles needed for determining the precise kinematics Baryons: HMS at momenta up to 5.1 GeV/c needs study of saturation effects on the needed excitation (99-118 suggests that they still are negligible up to 5.1 GeV/c) and on the optics (sieve slit runs needed) SOS at 1.6 GeV/c is definitely in the saturation regime; reliable (reproducable) way how to set the fields needed plus full optics study (sieve, Y, delta); check of offsets with 1H(e,e'p) ("heepcheck") at E'=1.6 GeV/c Fpi: HMS standard SOS needs check of optics at 0.8 GeV/c and full calibration at 1.76 GeV/c; offsets to be checked with 1H(e,e'p) at both settings Limitations: At higher E_e the count rate for 1H(e,e'p) with e' in SOS gets rather small, since Q2 has to be large because E_e' must be below 1.76 GeV in SOS. (the luminosity of a 50 muA beam on a 4 cm LH2 target is 3*10^8 fm^-2; the elastic cross sections are listed as 'sigma' below) It is of no use to reverse the roles of SOS and HMS for heepcheck, since the polarity changes most probably introduce unwantedly large systematic uncertainties. Remark about elastics (single) with HMS: the position of the elastic peak yields a(n angle dependent) relation between E, E' and theta, while the yield gives a check on our overall normalization; measuring at a range of angles costs hardly any time and gives us detailed information Specific calibration runs. -------------------------- During commissioning and preparation of F2: 1.14 GeV beam SOS delta scan at 0.8 GeV/c setting with H elastic e-e th_e' e_e' sigma 1140.0 35.0 934.6 0.1182E-04 1140.0 40.0 887.7 0.5411E-05 1140.0 45.0 840.8 0.2690E-05 1140.0 50.0 795.0 0.1437E-05 1140.0 55.0 750.9 0.8182E-06 1140.0 60.0 709.2 0.4931E-06 1140.0 65.0 670.0 0.3126E-06 at 50 degrees combined with heepcheck (HMS on + polarity) e_e th_e' e_e' q th_q Q2 sigma 1140.0 50.0 795.0 875.5 44.1 0.65 0.1437E-05 During F2: 2.24 GeV beam SOS optics check with sieve and quintar at 0.8 GeV/c (can also be done at 3.32 or 4.40 GeV) th_e' = 15 degrees (count rate?) SOS delta scan at 1.76 GeV/c setting with H elastic e-e th_e' e_e' sigma 2240.0 20.0 1958.1 0.2037E-04 2240.0 23.0 1882.7 0.8165E-05 2240.0 26.0 1804.1 0.3560E-05 2240.0 29.0 1724.0 0.1673E-05 2240.0 32.0 1643.7 0.8401E-06 2240.0 35.0 1564.5 0.4480E-06 2240.0 38.0 1487.3 0.2522E-06 SOS delta scan at 1.60 GeV/c setting with H elastic e-e th_e' e_e' sigma 2240.0 23.0 1882.7 0.8165E-05 2240.0 26.0 1804.1 0.3560E-05 2240.0 29.0 1724.0 0.1673E-05 2240.0 32.0 1643.7 0.8401E-06 2240.0 35.0 1564.5 0.4480E-06 2240.0 38.0 1487.3 0.2522E-06 2240.0 41.0 1412.7 0.1490E-06 2240.0 44.0 1341.3 0.9202E-07 heepcheck with SOS at 1.76 GeV/c e_e th_e' e_e' q th_q Q2 sigma 2240.0 28.0 1750.8 1075.8 49.8 0.92 0.2135E-05 heepcheck with SOS at 1.60 GeV/c e_e th_e' e_e' q th_q Q2 sigma 2240.0 34.0 1590.8 1280.6 44.0 1.22 0.5490E-06 HMS elastic e-e th_e' e_e' sigma 2240.0 10.5 2153.9 0.8074E-03 2240.0 14.0 2091.7 0.1741E-03 2240.0 18.0 2005.7 0.3953E-04 2240.0 22.0 1908.3 0.1097E-04 2240.0 26.0 1804.1 0.3560E-05 2240.0 30.0 1697.2 0.1320E-05 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 2240.0 15.0 1000.0 2240.0 15.0 600.0 2240.0 15.0 450.0 3.32 GeV beam HMS elastic e-e th_e' e_e' sigma 3320.0 10.5 3134.3 0.2067E-03 3320.0 14.0 3004.2 0.3389E-04 3320.0 18.0 2829.9 0.5908E-05 3320.0 22.0 2639.9 0.1342E-05 3320.0 26.0 2444.6 0.3782E-06 3320.0 30.0 2252.3 0.1276E-06 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 3320.0 12.0 2000.0 4.44 GeV beam SOS optics check with sieve and quintar at 1.6 GeV/c th_e' = 15 degrees (count rate?) SOS optics check with sieve and quintar at 1.76 GeV/c th_e' = 15 degrees (count rate?) HMS elastic e-e th_e' e_e' sigma 4400.0 10.5 4079.7 0.6083E-04 4400.0 13.0 3927.9 0.1361E-04 4400.0 16.0 3723.6 0.2857E-05 4400.0 20.0 3430.0 0.4926E-06 4400.0 24.0 3130.7 0.1145E-06 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 4440.0 12.0 3000.0 4440.0 12.0 2000.0 4440.0 12.0 1000.0 4440.0 12.0 600.0 4440.0 12.0 450.0 During Baryons 5.50 GeV beam elastics in HMS e_e th_e' e_e' sigma 5500.0 12.0 4875.5 0.7027E-05 5500.0 15.0 4584.4 0.1189E-05 5500.0 18.0 4273.9 0.2645E-06 5500.0 21.0 3958.7 0.7355E-07 5500.0 24.0 3650.2 0.2455E-07 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 5500.0 12.0 5000.0 5500.0 12.0 4500.0 5500.0 12.0 4000.0 5500.0 12.0 3500.0 5500.0 12.0 3000.0 SOS sieve check with thin (2mm?) C target e-e th_e' e_e' 5500.0 40.0? 1600.0 heepcheck at kinematics of experiment: e_e th_e' e_e' q th_q Q2 sigma 5500.0 55.0 1571.6 4775.4 15.6 7.37 0.7297E-10 count rate is very small, but a check on the direction of q-vec, which is determined by SOS in the saturation region, seems essential; fortunately the high momentum setting of the actual experiment includes this kinematics (should be checked with a simulation; and is the resolution good enough?) During Fpi 5.30 GeV beam elastics in HMS e_e th_e' e_e' sigma 5300.0 12.0 4717.7 0.8725E-05 5300.0 15.0 4444.6 0.1508E-05 5300.0 18.0 4152.1 0.3399E-06 5300.0 21.0 3854.1 0.9518E-07 5300.0 24.0 3561.0 0.3188E-07 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 5300.0 12.0 3400.0 NB. is sieve with HMS on + polarity same as for - polarity? difficult to check; use the few positrons? SOS sieve check with thin (2mm?) C target e-e th_e' e_e' 5300.0 40.0? 1760.0 heepcheck e_e th_e' e_e' q th_q Q2 sigma 5300.0 50.0 1756.3 4382.7 17.9 938.3 6.65 0.1617E-09 same remark as for Baryons: low count rates; how much statistics needed? 4.70 GeV beam elastics in HMS e_e th_e' e_e' sigma 4700.0 12.0 4236.3 0.1707E-04 4700.0 15.0 4014.8 0.3172E-05 4700.0 18.0 3774.6 0.7490E-06 4700.0 21.0 3526.7 0.2156E-06 4700.0 24.0 3279.7 0.7328E-07 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 4700.0 12.0 3000.0 SOS sieve check with thin (2mm?) C target e-e th_e' e_e' 4700.0 40.0? 1760.0 heepcheck e_e th_e' e_e' q th_q Q2 sigma 4700.0 48.0 1768.7 3754.1 20.5 5.50 0.4589E-09 same remark as for Baryons: low count rates; how much statistics needed? 4.25 GeV beam elastics in HMS e_e th_e' e_e' sigma 4250.0 12.0 3867.2 0.2890E-04 4250.0 16.0 3615.6 0.3509E-05 4250.0 20.0 3338.1 0.6153E-06 4250.0 24.0 3054.1 0.1443E-06 4250.0 28.0 2777.4 0.4277E-07 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 4250.0 12.0 3400.0 SOS sieve check with thin (2mm?) C target e-e th_e' e_e' 4250.0 40.0? 800.0 heepcheck e_e th_e' e_e' q th_q Q2 sigma 4250.0 51.0 1586.4 3477.5 20.8 5.00 0.6098E-09 useful? th_e' is what we will use for Fpi, but e_e' is far off 3.77 GeV beam elastics in HMS e_e th_e' e_e' sigma 3770.0 12.0 3465.7 0.5183E-04 3770.0 16.0 3262.2 0.6943E-05 3770.0 20.0 3034.7 0.1295E-05 3770.0 25.0 2738.9 0.2291E-06 3770.0 30.0 2450.8 0.5590E-07 HMS sieve check with thin (2mm?) C target e-e th_e' e_e' 3770.0 12.0 3000.0 SOS sieve check with thin (2mm?) C target e-e th_e' e_e' 3770.0 40.0? 800.0 heepcheck e_e th_e' e_e' q th_q Q2 sigma 3770.0 44.0 1771.9 2782.5 26.3 3.75 0.3471E-08 useful? th_e' is what we will use for Fpi, but e_e' is far off