GlueX Offline Meeting, September 21, 2011
GlueX Offline Software Meeting
Wednesday, September 21, 2011
1:30 pm EDT
JLab: CEBAF Center F326
Contents
Agenda
- Announcements
- Review of minutes from the last meeting: all
- Reconstruction sub-group reports
- Calorimeters: Matt
- Tracking: Simon
- PID: Paul M.: GlueX Particle ID, Uncertainties Update
- Compressed Data Format Update: Richard or Igor
- BCAL Reconstruction Update: Will
- Plug-in to extract single particles from multi-particle events (email) : David
- Tracking explained: Simon
- Resources: an idea for managing large files: Dmitry
- Collaboration Meeting Agenda
- Action Item Review
- Review of recent repository activity: all
Communication Information
Telephone
To connect by telephone:
- dial:
- US and Canada: (866)740-1260 (toll free)
- International: (303)248-0285 (toll call) or look up toll-free number at http://www.readytalk.com/intl
- enter access code followed by the # sign: 3421244#
Video Conferencing
- ESNet: 8542553
- EVO:
- Meeting URL: http://evo.caltech.edu/evoNext/koala.jnlp?meeting=292I2iMeMB929nDs9aD9
- Phone Bridge ID: 10 1789
Slides
Talks can be deposited in the directory /group/halld/www/halldweb1/html/talks/2011-3Q on the JLab CUE. This directory is accessible from the web at https://halldweb1.jlab.org/talks/2011-3Q/ . You have to be a member of the "halld" Unix group to do this.
Minutes
Present:
- CMU: Will Levine, Paul Mattione, Curtis Meyer
- IU: Ryan Mitchell, Kei Moriya, Matt Shepherd
- JLab: Hovanes Egiyan, Mark Ito (chair), David Lawrence, Yi Qiang, Dmitry Romanov, Elton Smith, Sascha Somov, Simon Taylor, Elliott Wolin
- Regina: Andrei Semenov
- FSU: Nathan Sparks
Announcements
- Mark announced that, by default, we will not be using the phone anymore at these meetings. I someone does happen to have a need for a phone connection, just let Mark know in advance.
- Elliott announced that he and David will be attending the CLAS12 Service Oriented Architecture Workshop. Contact Elliott for more information.
Reconstruction sub-group reports
Calorimetry
Matt gave the report.
- switch from 3-3-4 segmentation to 1-2-3-4 segmentation
- geometry specification not as flexible as originally thought
- Will is working on it
- timing offsets
- talking to Mihajlo: time is set by time of highest energy block
- x,y,z is not taken into account
- will take some work and attention: Matt will work on this
Tracking
Simon gave the report.
- some problems have to do with the quality of track candidates
- found issues with starting angle guess for very forward going tracks
- fixed up angle in track candidate
- some other minor changes
- farming out fiducial cut study a possible issue
- note: design goal for forward direction: down to one degree
PID
Paul gave the report.
- revised PID scheme: see his slides
- original slides presented at last Physics meeting
- changes based on feedback received on email list
- referred us to the slides for details
- Beni: HERMES scheme used log of prob ratios
- Beni will send around description of the scheme
- idea: instead of adding chi-squared's, try to weight chi-squared from different sources
- the way to do that is not clear
- errors may be correlated
- motivation: what if a single hit on a track if spurious: isn't that an out-sized effect on the sum of chi-squared's?
- some skepticism expressed about validity of this concern
BCAL Reconstruction Update
Will described his recent work. See his wiki page for details.
- working on the new 1-2-3-4 segmentation of the BCAL
- did some studies with π0's and resulting errors from kinematic fitting
variable thresholds in code now. not how it will be done david
Andrei: segmentation scheme, not agree, reconstrcution code effects energy resolution. if noise added or hits missed calibration will bias means
bother updating kloe: kloe default is still used in the fine segmentation scheme keep to kloe alive, keep for now
david
single particle plugin if two particles, two events are made
simon
