Difference between revisions of "JEF meeting Aug 31, 2015"
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=Agenda= | =Agenda= | ||
*[https://halldweb1.jlab.org/wiki/index.php/JEF_meeting_Jun_8,_2015#Agenda Task list] updates | *[https://halldweb1.jlab.org/wiki/index.php/JEF_meeting_Jun_8,_2015#Agenda Task list] updates | ||
− | * TOF PID study from toy simulation (Dave) | + | *[https://cnidlamp.jlab.org/RareEtaDecay/JDocDB/node/78 TOF PID study from toy simulation ](Dave) |
* Neutral survey (All) | * Neutral survey (All) | ||
+ | |||
+ | =Minutes= | ||
+ | Attendees: J. Feng, L. Gan., B. Karki, D. Mack, A. Somov, S. Taylor, J. Stevens | ||
+ | *Dave gave a report about his toy monte-carlo studies of proton/kaon/pion separation using time-of-flight with the GlueX detector | ||
+ | ** Using a nominal 100 ps timing resolution and 3% momentum resolution for forward-tracks, expect e-/π separation below ~1 GeV/c, π/K separation below ~3 GeV/c, K/proton separation below ~6 GeV/c | ||
+ | ** Looked at mass distributions computed using p and beta -- maybe not ideal for using in a confidence-level analysis because of non-Gaussian tails | ||
+ | ** Some understanding of ghost bands seen in PID plots from real data = wrong beam bucket | ||
+ | *** Biggest impact is for kaon id | ||
+ | * We discussed what the next step in the survey of neutral final states started by Bishnu and Justin (looking at final states with 2 photons) | ||
+ | ** Expand survey to include 2π0, 3π0, etc.? | ||
+ | ** Focus on channels that might lead to the first papers from the commissioning data? | ||
+ | *** Exclusive π0 production, looking at Σ beam asymmetry? | ||
+ | *** η production cross section? | ||
+ | ** Consensus was to continue the 2γ work started by Bishnu and Justin, focussing on asymmetries/angular distributions while we work out the details of normalization. | ||
+ | *Sascha reported that pieces are starting to come together for magnetic shielding studies (Hall probe, a Helmholtz coil is available, perhaps a permanent magnet?). Jing and Sascha will start working on setting up for measurements next week. | ||
+ | In particular we need to determine how many layers of mu-metal will be needed and whether we need a soft-iron outer layer as well. | ||
+ | *Sascha lead a discussion regarding PMTs for the insert crystals | ||
+ | ** Peak anode current needs to be considered carefully -- non-linearity? Need to do some work on divider design. | ||
+ | ** Hamamatsu have another PMT (other than the round-face model we have been considering) with a square face (2.3x2.3 cm^2) that can handle higher peak current | ||
+ | ** Hammatsu have cheaper (but with worse performance) round-face PMTs than the ones we've been considering. |
Latest revision as of 16:24, 3 September 2015
Meeting time and location= 13:30 EST (JLab time) CC F326-327
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Agenda
- Task list updates
- TOF PID study from toy simulation (Dave)
- Neutral survey (All)
Minutes
Attendees: J. Feng, L. Gan., B. Karki, D. Mack, A. Somov, S. Taylor, J. Stevens
- Dave gave a report about his toy monte-carlo studies of proton/kaon/pion separation using time-of-flight with the GlueX detector
- Using a nominal 100 ps timing resolution and 3% momentum resolution for forward-tracks, expect e-/π separation below ~1 GeV/c, π/K separation below ~3 GeV/c, K/proton separation below ~6 GeV/c
- Looked at mass distributions computed using p and beta -- maybe not ideal for using in a confidence-level analysis because of non-Gaussian tails
- Some understanding of ghost bands seen in PID plots from real data = wrong beam bucket
- Biggest impact is for kaon id
- We discussed what the next step in the survey of neutral final states started by Bishnu and Justin (looking at final states with 2 photons)
- Expand survey to include 2π0, 3π0, etc.?
- Focus on channels that might lead to the first papers from the commissioning data?
- Exclusive π0 production, looking at Σ beam asymmetry?
- η production cross section?
- Consensus was to continue the 2γ work started by Bishnu and Justin, focussing on asymmetries/angular distributions while we work out the details of normalization.
- Sascha reported that pieces are starting to come together for magnetic shielding studies (Hall probe, a Helmholtz coil is available, perhaps a permanent magnet?). Jing and Sascha will start working on setting up for measurements next week.
In particular we need to determine how many layers of mu-metal will be needed and whether we need a soft-iron outer layer as well.
- Sascha lead a discussion regarding PMTs for the insert crystals
- Peak anode current needs to be considered carefully -- non-linearity? Need to do some work on divider design.
- Hamamatsu have another PMT (other than the round-face model we have been considering) with a square face (2.3x2.3 cm^2) that can handle higher peak current
- Hammatsu have cheaper (but with worse performance) round-face PMTs than the ones we've been considering.