Difference between revisions of "June 30, 2016 Calorimeter"
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##* Finds consistent parameters for both charged (pions) and neutral hits. | ##* Finds consistent parameters for both charged (pions) and neutral hits. | ||
##* To find optimal timing, need also to make position dependent corrections | ##* To find optimal timing, need also to make position dependent corrections | ||
− | ##* | + | ##* Checked hypotheses for non-constant veff data. Found consistency with explanation of shower size influence on timing |
+ | ##* Using quadratic for for veff finds good resolution and correct systematic effects seen in pi+ timing. There remain systematic issues in the proton timing. | ||
+ | ##* Conclude that for optimal timing, corrections will be needed which depend on particle type and position of energy deposition | ||
+ | ##* Mark: Need to clarify nomenclature: time-walk should be a function of pulse height only. Andrei: Notes that shower (and energy deposition) does depend on particle type and therefore could depend on pid and possibly position. | ||
+ | ##* Elton: From a practical view of calibrations, we should have a time-walk correction that only depends on pulse height at the level of hits. Corrections to the timing (at the shower level) could be done at a higher level using all hits in a shower. | ||
+ | ##* Zisis: Andrei and Tegan will be checking consistency of MC with data over the next month. Will take this discussion offline. | ||
##[http://argus.phys.uregina.ca/cgi-bin/private/DocDB/ShowDocument?docid=3075 Michel electron update] | ##[http://argus.phys.uregina.ca/cgi-bin/private/DocDB/ShowDocument?docid=3075 Michel electron update] | ||
# Reconstruction and Simulation | # Reconstruction and Simulation | ||
##[https://gluexdirc.mit.edu/neutron-efficiency-5 Neutron efficiency] | ##[https://gluexdirc.mit.edu/neutron-efficiency-5 Neutron efficiency] | ||
# Any other business | # Any other business |
Revision as of 15:08, 30 June 2016
Contents
Video Conferencing Information
Meeting Time: 12:00 p.m.
- To join via a Web Browser, go to the page [1] https://bluejeans.com/907185247.
- To join via Polycom room system go to the IP Address: 199.48.152.152 (bjn.vc) and enter the meeting ID: 907185247.
- To join via phone, use one of the following numbers and the Conference ID: 907185247.
- US or Canada: +1 408 740 7256 or
- US or Canada: +1 888 240 2560
- Upon connection all microphones are automatically muted. To unmute your mike on a Polycom or equivalent unit, enter *4. Unmuting on a computer is trivial as there is a microphone button than can be clicked.
- More information on connecting to bluejeans is available.
Participant Direct Lines
- JLab Phone: in CC F326 is 757-269-6460 (usual room)
- JLab Phone in CC L207 is 757-269-7084
- Phone in the Regina Video-conference Suite is 306-585-4204
- Athens Phone: in Christina's office is 011-30-210-727-6947
Action Items
References
Tentative Agenda
- Announcements
- Action Items
- Preparation for REST production
- FCAL non-linear shower corrections update
- BCAL update
- Calibrations
- Reconstruction and Simulation
- Any other business
Minutes
Attendees: Elton, Jon, Adesh, Mark (JLab); Zisis, Ahmed, Andrei, Tegan, Colleen (UofR); Curtis (CMU); Sean (NW); George (Athens); Maria (MIT);
- Announcements
- Manuel Lara is defending his thesis today.
- Action Items
- Preparation for REST production
- Adesh: Preparing non-linear constants for FCAL for upcoming launches. Need one set for each of the two sets of HV settings.
- FCAL non-linear shower corrections update
- Use symmetric showers (shower energies close to each other) from pi0 decays
- Non-linear corrections set to 1 up to now
- Parameterization is a piece-wise correction with linear fit (<1.5 GeV) and exponential (>1.5 GeV)
- After correction a scale factor of about 1.005 needs to be applied to the data.
- MC resulted in pi0 peak at about 90 MeV when new non-linear corrections were applied. This was due to the fat that the original non-linear correction included a scale factor in addition to an energy dependent correction.
- Fix to MC includes introduction of a scale factor (~1.3) and new parameterization.
- Non-linear parameterization for MC uses only an exponential. This is included in the program by adding a parameter for the transition between linear and exponential functions (set to 0 for MC, set to 1.5 GeV for data)
- Adjusted per block energy threshold (reduced by about 20 down to 13 MeV).
- Code changes needed to be made to match the parameter additions to CCDB. These have been completed and ready for next launch.
- Long-term plan for matching MC and data non-linear behavior is to have the MC output digi-hits. This will allow using gain calibrations in MC, similar to the way it is done for data (using pi0 calibration). Matt will work on this.
- Next effort will be to determine timing offsets.
- Mark: How is this done? Answer: Use global fit to match timing of adjacent hits in a single shower. Mark: Check that low-energy hits are excluded from calibration sample.
- BCAL update
- Calibrations
- Z-Dependance in the Time Calibration of BCAL (Andrei)
- Use charged and neutral hits to develop time-walk corrections
- Finds consistent parameters for both charged (pions) and neutral hits.
- To find optimal timing, need also to make position dependent corrections
- Checked hypotheses for non-constant veff data. Found consistency with explanation of shower size influence on timing
- Using quadratic for for veff finds good resolution and correct systematic effects seen in pi+ timing. There remain systematic issues in the proton timing.
- Conclude that for optimal timing, corrections will be needed which depend on particle type and position of energy deposition
- Mark: Need to clarify nomenclature: time-walk should be a function of pulse height only. Andrei: Notes that shower (and energy deposition) does depend on particle type and therefore could depend on pid and possibly position.
- Elton: From a practical view of calibrations, we should have a time-walk correction that only depends on pulse height at the level of hits. Corrections to the timing (at the shower level) could be done at a higher level using all hits in a shower.
- Zisis: Andrei and Tegan will be checking consistency of MC with data over the next month. Will take this discussion offline.
- Michel electron update
- Z-Dependance in the Time Calibration of BCAL (Andrei)
- Reconstruction and Simulation
- Any other business