Commissioning Calibration Data
Contents
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 | Cross Section @ Eγ ~ 5 GeV |
|---|---|---|
| p γ → p π0 | ~180 nb (ref) | ~400 nb (ref) |
| p γ → p η ; η → γ γ | ~30 nb (ref) | |
| p γ → p ρ0 ; ρ0 → π+ π- | 13.5 ± 0.5 μb (ref) | 15.9 ± 0.7 μb (ref) |
| p γ → p ω ; ω → γ π0 | 160 ± 20 nb (ref) | 250 ± 20 nb (ref) |
| p γ → p ω ; ω → π+ π- π0 | 1.7 ± 0.3 μb (ref) | 2.7 ± 0.3 μb (ref) |
| p γ → p φ ; φ → K+ K- | 270 ± 30 nb (ref) | 200 ± 40 nb (ref) |
| p γ → p KS + X | ||
| p γ → Λ K+ ; Λ → p π- |
Tagging Events
Online Tagging
The L3 trigger will allow for tagging events that could be interesting for calibration procedures at the online level. The full reconstruction will not be available, most likely full or almost-full shower reconstruction and track candidates (maybe wire-based tracking for a subset of the events).
Mechanisms
- JANA Event Status bits
- 64 bits total are available
- 9 are already defined
- Need to decide how bits we want
- New data type?
- More work, more flexible
Event classes
- inclusive pi0, 2FCAL, FCAL+BCAL, 2BCAL
- inclusive eta 2BCAL, FCAL+BCAL
- 2 pos. track, 1 neg. track (p γ → p ρ0, p γ → p φ ; φ → K+ K-)
- 2 pos. track, 1 neg. track, π0 (p γ → p ρ0 ; ρ0 → π+ π-)
- π0, photon (p γ → p ω ; ω → γ π0)
- displaced vertex?
Quality criteria TBD.
Offline Tagging
Spring 2016
Calibration data needs as of Jan. 26, 2016
| Detector | Status | Data in Hand | Est. Data Needed | Est. Running Time | Notes |
|---|---|---|---|---|---|
| BCAL | More Needed | 60k pi0 | 10(40)x | ~40(160) hr | pi0 cluster energy > 750 MeV, estimates for 3(4) layer calibration |
| CDC | OK | Check fADC125 algorithm with beam data | |||
| FCAL | More Needed | 100k pi0 | >10x | ? | pi0 cluster energy > 1 GeV |
| FDC | OK | Check fADC125 algorithm with beam data | |||
| PS/PSC | OK | ||||
| Start Counter | More Needed | 80 M tracks | 10x | ~4 hr | basic calibrations are good, more refinement possible |
| TAGH | OK | ||||
| TAGM | OK | ||||
| TOF | OK | need to verify stability of calibrations with more data |
Data sizes and projected running times based on data taken in Fall 2015/Jan. 2016.
Notes
- Running time estimates assume 100 nA beam, 10^-4 RL amorphous radiator
- Data needed depends strongly on S/B, especially for calorimeters. Lowering thresholds can have a large effect, too
- CDC/FDC new fADC125 firmware being calibrated with cosmics on hand.
- HV Scans: CDC, TOF, PS
- Threshold scans: SC
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 | 410k pi0 | 10x | ~4 - 8 hr | pi0 cluster energy > 500 MeV |
| 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 |
