Commissioning Calibration Data

From GlueXWiki
Revision as of 19:00, 2 November 2015 by Sdobbs (Talk | contribs) (Final States Used For Calibrations)

Jump to: navigation, search

Final States Used For Calibrations

This is a partial list of final states that can be used for calibrations. Fully reconstructed reactions give clean inputs to calibrations procedures. It would be helpful to have rate/efficiency studies for these reactions.

Assuming electron beam @ 12 GeV

Reaction Cross Section @ Eγ ~ 9 GeV (μb) Cross Section @ Eγ ~ 5 GeV (μb)
p γ → p π0
p γ → p η ; η → γ γ
p γ → p ρ0 ; ρ0 → π+ π- 13.5 ± 0.5 (ref) 15.9 ± 0.7 (ref)
p γ → p ω ; ω → γ π0 0.16 ± 0.02 (ref) 0.25 ± 0.02 (ref)
p γ → p ω ; ω → π+ π- π0 1.7 ± 0.3 (ref) 2.7 ± 0.3 (ref)
p γ → p φ ; φ → K+ K- 0.27 ± 0.03 (ref) 0.20 ± 0.04 (ref)
p γ → p KS + X
p γ → Λ K+ ; Λ → p π-

Fall 2015

Calibration data needs as of Oct. 6, 2015

Detector Status Data in Hand Est. Data Needed Est. Running Time Notes
BCAL More Needed 130k pi0 25-50x ~43 - 85 hr pi0 cluster energy > 750 MeV
CDC OK 350 M cosmics
FCAL More Needed 125k pi0 10x ~1 - 2 hr pi0 cluster energy > 1 GeV
FDC OK 3 shifts, 10^-4 radiator, 100 nA, no field needed
PS/PSC OK
Start Counter More Needed 80 M tracks 10x ~4 hr basic calibrations are good, more refinement possible
TAGH OK
TAGM More Needed 10 M - 50 M 4 hr
TOF OK need to verify stability of calibrations with more data

Projected running times scaled up from conditions in Run 3185. Assumes 12 GeV e- beam with 100 nA current.

Notes

  • Data needed depends strongly on S/B, especially for calorimeters.
  • Lowering thresholds can have a large effect, too
  • SC run list: 2931, 2932, 2933, 2934
  • BCAL/FCAL run list: 2931, 3185 [diamond]; 3079, 3179, 3180, 3182, 3199, 3200, 3201, 3217 [1x10-4 RL amorphous]
    • Scaling factor: diamond = 8 x amorphous
  • CDC/FDC will need more data to calibrate fADC125 algorithm when it's deployed.

Scaling from 6 GeV to 12 GeV

  • 6 GeV settings: 5.5 GeV e- beam, 50 um diamond radiator, 5 mm collimator, E(gam) = 2 - 5.5 GeV
  • 12 GeV settings: 12 GeV e- beam, 20 um diamond radiator, 3.4 mm collimator, E(gam) = 7 - 12 GeV
  • rate(12 GeV) / rate(6 GeV) ~ 80% [using cobrems in bggen, incl. plastic target on nose removal in 12 GeV era].
  • Geometrical factors: (12 GeV/6 GeV)
    • SC - ~1x (straight section drives needs)
    • BCAL - ~1x (both photons in BCAL)
    • FCAL - ~8x (both photons in FCAL)

Runs

Run Events Run Time (hr) Evts/hr
3185 19.9 M 2.2 9.0 M
2931 74.6 M 7.4 10.1 M
2932 0.4 M 0.1 4.0 M
2933 3.0 M 0.7 4.3 M
2934 3.6 M 1.5 2.4 M
3079 25.9 M 7.0 3.7 M
3179 14.6 M 1.75 8.3 M
3180 41.3 M 4.8 8.6 M
3199 4.4 M 3.0 1.5 M
3200 12.5 M 9.0 1.4 M
3201 5.6 M 5.4 1.0 M
3217 10.8 M 6.3 1.7 M