Difference between revisions of "Analysis Miscellaneous"
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(→RF Beam Bunch Selection & PID Details) |
(→RF Beam Bunch Selection & PID Details) |
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* In <span style="color:#0000FF">DEventRFBunch_factory</span>: Use (in order of preference) (need at least one of): | * In <span style="color:#0000FF">DEventRFBunch_factory</span>: Use (in order of preference) (need at least one of): | ||
| − | + | # Tracks with good tracking FOM: SC hits | |
| − | + | # Tracks with good tracking FOM: BCAL/TOF/FCAL hits | |
| − | + | # All Tracks: SC hits | |
| − | + | # All Tracks: BCAL/TOF/FCAL hits | |
| − | + | # All Neutral Showers (assume all PIDs = photon) | |
| − | + | # Use original DRFTime and set DEventRFBunch::dMatchedToTracksFlag to false | |
* Vote: select the RF bunch that matches the most times. The RF bunch times are the DRFTime +/- multiples of 2.004 ns. | * Vote: select the RF bunch that matches the most times. The RF bunch times are the DRFTime +/- multiples of 2.004 ns. | ||
Revision as of 00:09, 14 September 2014
Contents
Tricks for saving time and memory
- Change the binning and/or range of the built-in histograms after constructing the corresponding DAnalysisAction object.
- Because there may be many DParticleCombo objects for an event, perform as many cuts as possible prior to kinematic fitting.
- This includes extremely-loose cuts (well beyond the range at which your final cut will be) on all of the physical quantities of interest (e.g. mass peaks).
- To branch an analysis, create a new (but identical) DReaction object (with the same DReactionStep pointers), then simply repeat or change any of the DAnalysisActions.
- If the DReactionStep objects are re-used, the framework will realize that the DParticleComboBlueprintStep objects will be the same, and will simply reuse them.
- Note that the DParticleCombo objects will not be identical since they will contain a pointer to a different DReaction.
- If the kinematic fit type is also the same, it will skip the kinematic fit of the new DParticleCombo objects entirely and just copy the previous results since they will be identical.
- If the DReactionStep objects are re-used, the framework will realize that the DParticleComboBlueprintStep objects will be the same, and will simply reuse them.
RF Beam Bunch Selection & PID Details
How RF bunch selection works for an event (creating a single DEventRFBunch object)
- In DEventRFBunch_factory: Use (in order of preference) (need at least one of):
- Tracks with good tracking FOM: SC hits
- Tracks with good tracking FOM: BCAL/TOF/FCAL hits
- All Tracks: SC hits
- All Tracks: BCAL/TOF/FCAL hits
- All Neutral Showers (assume all PIDs = photon)
- Use original DRFTime and set DEventRFBunch::dMatchedToTracksFlag to false
- Vote: select the RF bunch that matches the most times. The RF bunch times are the DRFTime +/- multiples of 2.004 ns.
How DChargedTrackHypothesis PID FOM calculation works
- Determine the track start time:
- Try: match the track to its RF bunch using the method described above.
- Else try: use the DEventRFBunch RF time if it was matched to other tracks.
- Else try: use the measured track t0 time (ST, CDC) (will fail if t0 time = t1 time (e.g. both CDC (e.g. no ST/TOF/etc. hits of any kind)))
- Note: each track may match to a different RF bunch: this allows the correct PID to be determined for background tracks originating from nearby beam buckets.
- Propagate both the TOF/BCAL/etc. time and the RF time to the track vertex, and compare them to calculate FOM.
How DNeutralParticleHypothesis PID FOM calculation works
- Propagate shower times to the target center, compare them to the DEventRFBunch time.
