1. GlueX Upgrade Workshop Curtis Meyer

2. Participants 5/21/12GlueX Collaboration Meeting2 Barnes, Alexander UCONNBarnes, Frank DOE/NP Chudakov, Eugene JlabCrede, Volker FSU Doughty, David CNUDugger, Michael ASU Egiyan, Hovanes JlabEugenio, Paul FSU Gan, Liping UNCW Jarvis, Naomi CMUJones, Richard UCONN Lawrence, David JlabLeckey, John IU Livingston, Ken GlasgowMcIntyre, James UCONN Meyer, Curtis CMUMokaya, Fridah UCONN Pentchev, Lubomir Jlab Pratt, Brendan UCONN Qiang, Yi Jefferson Lab Senderovich, Igor Uconn. Shepherd, Matthew IU Smith, Elton JLab Sober, Daniel CUA Sparks, Nathan FSU Taylor, Simon Jlab Williams, Mike MIT Young, GlenJlab Zihlmann, BeniJLab

3. Workshop Agenda 5/21/12GlueX Collaboration Meeting3 8:15 Session Ia (15) --- Opening - Chair: 8:15 (15) --- Welcome and Goals - Curtis Meyer. 8:30 Session Ib (90) --- Calorimetry Upgrades - Chair: 8:30 (30) --- Upgrade FCAL with PWO Crystals -- Liping Gan 9:00 (30) --- Forward Calorimetry - Alex Somov 9:30 (30) --- Discussion - 10:00 (30) Coffee 10:30 Session Ic (60) --- Photon Beam Upgrades - Chair: 10:30 (20) --- Polarimetry - Mike Dugger 10:50 (20) --- Polarimetry: Prototype design and test in Mainz - Ken Livingston 11:10 (20) --- Discussion 11:30 Session Id (60) --- Upgrades - Chair: 11:30 (30) --- Level-three trigger - Elliott Wolin 12:00 (30) --- Discussion 12:30 (60) Lunch 13:30 Session IIa (125) --- Particle ID Upgrades - Chair: 13:30 (30) --- Forward PID - Yi Qiang 14:00 (30) --- Forward PID - Mike Williams 14:30 (30) --- Helium Drift Chamber - Lubomir Pentchev 15:00 (30) Discussion 15:30 Session IIb (30) --- Closeout - (Organizer:) Chair: 15:30 (30) --- Moving Forward, opportunities for SURA funding? - Curtis Meyer 16:00 Adjourn

4. Calorimeter Upgrades 5/21/12GlueX Collaboration Meeting4 Replace the FCAL with a new device based on lead-tungstate crystals. Appears to be needed for the rare-eta decay proposal that was just submitted. The right device would likely improve GlueX physics Would help in PrimEx.

5. Needed Work Simulation and reconstruction needs to be on par with the current FCAL. It is not accurate to compare GEANT/JANA with PrimEx parameterizations. IMHO need additional physics justifications to support the cost of this detector. – Show impact on GlueX/Spectroscopy – … Define how large this needs to be for various physics cases. Much is in progress for the PAC proposal in mid. June. 5/21/12GlueX Collaboration Meeting5

6. Polarimetry How well do we know our photon polarization? 5/21/12GlueX Collaboration Meeting6 Triplet Production Pair production off a nucleon: γ nucleon → nucleon e+ e-. For polarized photons σ = σ0[1 + PΣ cos(2φ)], where σ0 is the unpolarized cross section, P is the photon beam polarization and Σ is the beam asymmetry Triplet production off an electron: γ e- → eR- e+ e-, where eR represents the recoil electron Any residual momentum in the transverse direction of the e- e+ pair is compensated for by the slow moving recoil electron. This means that the recoil electron can attain large polar angles shifted about 90 degrees in the azimuthal direction relative to the plane containing the pair.

7. Polarimetry 5/21/12GlueX Collaboration Meeting7 96mm 48mm Front: 4 sectors 16 strips/sector Back: 16 sectors Cost: $7500 (back stock) Manufacturer: Micron Semiconductor

8. ROC EMUEMU EMUEMU EMUEMU EMUEMU EMUEMU EMUEMU Monitoring Farm No Rejection EMUEMU RAIDRAID SILO in Computer Center 2 PB/year 50 ROCs 6 EMUs 6 EMUs 12 Monitoring Nodes 1 EMU 16 TB 16 hrs Event Builder Crossbar DAQ at Low Luminosity 300 MByte/sec 300 MB/s 8

9. Low LuminosityHigh Luminosity L1 trigger rate20 kHz200 kHz Average event size15 kB Date rate off detector300 MB/s3 GB/s L3 rejectionNoneFactor 10 Rate to storage300 MB/s Level-3 Trigger 9 100 Hz/core, have 200kHz of rate 2000 compute cores ~200 k$ Storage cost to skip L3 is ~500k$/year Get level-3 sooner rather than later!

10. Particle Identification 5/21/12GlueX Collaboration Meeting10 GlueX was proposed as an experiment to map out the light-quark spectrum of QCD exotics including strangeonium states. These latter states decay predominantly to final states that include kaons. Our Forward PID system (Gas threshold Cherenkov) was descoped in 2008 to build up a project contingency. Our just-submitted proposal focuses on the final states with strangeness. We need to revisit the best approach to get “excellent” PID in the forward direction to be able to carry out our physics.

11. Three Proposals 5/21/12GlueX Collaboration Meeting11 Yi Qaing - HBRICH Gem-readout based detector that could sit in the tracking volume between the FDC packages. Mike Williams – LHCb style RICH design that would fit in the original space reserved for a Cherenkov system. Lubomir Pentchev – Helium filled drift chambers using cluster counting.

12. A HBRICH Detector for GlueX A conceptual design inside the Barrel – Momentum coverage: 1.2 – 4.5 GeV/c Refractive index: n > 1.1 – Angular Coverage: 0 – 15 degrees Before the 3 rd FDC – May impact tracking badly. o Proximity focus, mirror less o Primary radiator: 15 mm Freon, n = 1.28 o Secondary Radiator: CF 4 o Cs-I GEM covers end cap and barrel region o Immune to magnetic field

13. LHCb RHICH-1 Design 5/21/12GlueX Collaboration Meeting13 Might be able to nearly copy an existing design, but the readout can probably be smaller. We don’t have the complicated LHCb events. Only covers the forward ~10- degree hole, but has excellent PID from where the TOF gives up to beyond 10 GeV/c.

14. 14 Modification of FDC Two eight-chamber packages ZERO material: Helium replaces air that mostly compensates for additional material THEREFORE: Can be placed in between FDC packages as close as possible to target for higher angular acceptance Provides both: PID and TRACKING Helium Cluster Counting

15. Moving Forward Need to put the various geometries into our MC and see how they impact tracking and photon reconstruction. We need all of these for our physics Look at PID with kinematic fitting to try and judge how well we need to be able to do under the missing baryon (1C) scenario. See how well the PID systems match our physics needs. 5/21/12GlueX Collaboration Meeting15

16. Summary A very useful 1-day workshop. It is great to see people thinking about new ideas, and this sort of focused forum is very useful to get ideas out. We have plans for moving forward on all fronts. This would certainly be a useful workshop to hold on a more regular basis. 5/21/12GlueX Collaboration Meeting16