Revision as of 14:07, 13 November 2015

Overview

We propose to run a "Calibration Challenge" starting the first week of December 2015.

The goal will be to take a run with zeroed out calibrations and to see how many calibrations can be automatically extracted.

Test runs will be performed in the weeks leading up to this challenge.

Types of Tests

Various types of tests could be run to exercise our calibration procedures.

1. Calibration values are normalized to some neutral value (e.g. 1 or 0), and the calibrations are derived "ab initio".
   • Given the diversity of run conditions among the few production runs in the spring data, it makes sense to do this test with just one run at a time, and not combine runs. Therefore, we can test calibrations that only need ~1 runs' worth of data.
2. Current calibration values are perturbed by some amount, and procedures are run to see how well the current values are recovered.
   • The perturbations would be specific to each calibration. Different functional forms? Gaussian? Square wave?
   • This would give us a way of testing calibrations that require more than one run's worth of data to be done from an uncalibrated state.

Types of Data

References:

• Automated Timing Calibrations
• Spring 2015 Dataset Summary

The largest spring production run is 2931, so that would be a good choice. It has the following charateristics:

• 50um diamond radiator
• 800A solenoid current
• 74M triggers

To test the tagger calibrations, PS triggered data is needed. Run 3180 looks good, it uses:

• amorphous radiator
• 1300A solenoid current
• 41M triggers

In principle, simulations could be used as well. Some effort is needed to work on the software to support this.

Calibration Classes

We can classify the calibrations by the type and amount of data needed. Only tables that have well-defined procedures have been included.

One Run Photon Beam Data

• All/base_time_offets
• CDC/timing_offsets
• FCAL/timing_offsets
• START_COUNTER/adc_timing_offsets
• START_COUNTER/tdc_timing_offsets
• START_COUNTER/timewalk_parms
• TOF/adc_timing_offsets
• TOF/tdc_timing_offsets
• TOF/...
• BCAL/TDC_offsets
• BCAL/ADC_timing_offsets
• BCAL/timewalk_tdc
• PHOTON_BEAM/RF/time_offset
• PHOTON_BEAM/RF/time_offset_var
• PHOTON_BEAM/RF/time_resolution_sq
• PHOTON_BEAM/hodoscope/fadc_time_offsets
• PHOTON_BEAM/hodoscope/tdc_time_offsets
• PHOTON_BEAM/microscope/fadc_time_offsets
• PHOTON_BEAM/microscope/tdc_time_offsets
• PHOTON_BEAM/pair_spectrometer/coarse/fadc_time_offsets
• PHOTON_BEAM/pair_spectrometer/coarse/tdc_time_offsets
• PHOTON_BEAM/pair_spectrometer/fine/fadc_time_offsets
• BCAL gain ratios
• BCAL/attenutation_parms

Future:

• Most basic FDC calibrations?

Multiple Run Photon Beam Data

• BCAL/ADC_gains
• FCAL/gains
• START_COUNTER/attenuation_factors
• START_COUNTER/propogation_speeds

Future:

• CDC/wire_aligment ?

Cosmic Data

• BCAL/effective_velocities?
• CDC/cdc_drift
• CDC/wire_aligment
• CDC/sag_parameters
• CDC/drift_parameters

• magnetic field dependence? other tracking corrections?

Plugin Requirements

Calibration plugins should satisfy the following guidelines:

1. Uses a DANA plugin to process the EVIO files
2. ROOT/text files are the preferred intermediate file format
3. The final output is a text file that can be used as an input to CCDB
4. Contains ROOT scripts to make plots that monitor/verifies the outputs
5. The outputs and execution steps are documented

If your plugin does not satisfy these, then please discuss the situation with the Calibration Coordinator (Sean), and we will develop a plan of action.

Challenge Type 1

We will focus on calibrations that can be fully done with one run's worth of beam data, ignoring calibrations that are best performed with cosmic data.

The following plugins will be used:

• BCAL_attenlength_gainratio
• BCAL_TDC_Timing
• HLDetectorTiming
• PSC_TW
• RF_online
• BCAL gains [upcoming] (Will M.)
• PS energies [upcoming] (Alex B.)
• SC timewalk [upcoming] (Mahmoud K.)
• TAGH timewalk [upcoming] (Nathan S.)
• TAGM timewalk [upcoming] (Alex B.)

Managing Constants

Outputs

The outputs of this exercise will be stored in /work/halld/calib_challenge

They will also be viewable from the web at: https://halldweb.jlab.org/calib_challenge/

Besides validation histograms and constant files, the following outputs will be generated:

• Histograms and TTrees for BCAL gain calibration

Run Plan

Pass 0

[Note: since passes 0 and 0.5 only need a small number of events, they are performed in the same job for efficiency]

Plugins: RF_online (coarse timing offsets)

Number of events: 100k (can be as low as 10k)

hd_root options: -PEVENTS_TO_KEEP=100000 -PPLUGINS=RF_online

Pass 0.5

Plugins: RF_online (fine timing offsets)

Number of events: 100k (can be as low as 10k)

hd_root options: -PEVENTS_TO_KEEP=100000 -PPLUGINS=RF_online

Pass 1

Plugins: HLDetectorTiming (rough timing + ADC/TDC alignment)

Number of events: all

hd_root options: -PHLDETECTORTIMING:DO_ROUGH_TIMING=1 ???

Pass 2

Plugins: HLDetectorTiming (per-channel alignment), BCAL timewalk, SC timewalk, PSC timewalk

Number of events: all

hd_root options: -PHLDETECTORTIMING:DO_TRACK_BASED=1

Pass 3

Plugins: TAGH timewalk, TAGM timewalk, BCAL_attenlength_gainratio, PS energies

Number of events: all

hd_root options:

Validation Pass

Number of events: all

plugins: all + BCAL gains

hd_root options: