Difference between revisions of "Commissioning Calibration Data"

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(Final States Used For Calibrations)
(Online Tagging)
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== Online Tagging ==
 
== 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'''
 +
 +
* [https://mailman.jlab.org/pipermail/halld-offline/2015-November/002172.html JANA Event Status bits]
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** 64 bits total are available
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** 9 are already defined
 +
** Need to decide how bits we want
 +
* New data type?
 +
** More work, more flexible
 +
 +
'''Event classes'''
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 +
* inclusive pi0, 2FCAL, FCAL+BCAL, 2BCAL
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* inclusive eta 2BCAL, FCAL+BCAL
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* 2 pos. track, 1 neg. track (p &gamma; &rarr; p &rho;<sup>0</sup>, p &gamma; &rarr; p &phi; ; &phi; &rarr; K<sup>+</sup> K<sup>-</sup>)
 +
* 2 pos. track, 1 neg. track, &pi;<sup>0</sup> (p &gamma; &rarr; p &rho;<sup>0</sup> ; &rho;<sup>0</sup> &rarr; &pi;<sup>+</sup> &pi;<sup>-</sup>)
 +
* &pi;<sup>0</sup>, photon (p &gamma; &rarr; p &omega; ; &omega; &rarr; &gamma;  &pi;<sup>0</sup>)
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* displaced vertex?
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Quality criteria TBD.
  
 
== Offline Tagging ==
 
== Offline Tagging ==

Revision as of 11:29, 13 January 2016

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

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