GlueX Upgrade Workshop

Curtis Meyer

GlueX Collaboration Meeting 2

Participants

5/21/12

Barnes , Alexander UCONN Barnes , Frank DOE/NP Chudakov, Eugene Jlab Crede , Volker FSU Doughty , David CNU

Dugger , Michael ASU Egiyan , Hovanes Jlab Eugenio , Paul FSU

Gan , Liping UNCW Jarvis , Naomi CMU Jones , Richard UCONN

Lawrence , David Jlab Leckey , John IU Livingston , Ken Glasgow

McIntyre , James UCONN Meyer , Curtis CMUMokaya , Fridah UCONN

Pentchev , Lubomir JlabPratt , 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, Glen

JlabZihlmann, Beni JLab

GlueX Collaboration Meeting 3

Workshop Agenda

5/21/12

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

GlueX Collaboration Meeting 4

Calorimeter Upgrades

5/21/12

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.

GlueX Collaboration Meeting 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.

5/21/12

GlueX Collaboration Meeting 6

PolarimetryHow well do we know our photon polarization?

5/21/12

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.

GlueX Collaboration Meeting 7

Polarimetry

5/21/12

96mm

48mm

Front: 4 sectors 16 strips/sector

Back: 16 sectors

Cost: $7500 (back stock)

Manufacturer: Micron Semiconductor

8

ROC

ROC

ROC

ROC

ROC

ROC

EMU

EMU

EMU

EMU

EMU

EMU

Monitoring Farm

No Rejection

EMU

RAID

SILO in Computer

Center

2 PB/year

50ROCs

6EMUs

6EMUs

12Monitoring

Nodes

1EMU

16 TB16 hrs

Event BuilderCrossbar

DAQ at Low Luminosity 300 MByte/sec

300 MB/s 300 MB/s300 MB/s

300 MB/s300 MB/s

300 MB/s

9

Low Luminosity High LuminosityL1 trigger rate 20 kHz 200 kHz

Average event size 15 kB 15 kB

Date rate off detector 300 MB/s 3 GB/s

L3 rejection None Factor 10

Rate to storage 300 MB/s 300 MB/s

Level-3 Trigger

Level-3 Trigger • 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!

GlueX Collaboration Meeting 10

Particle Identification

5/21/12

• 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.

GlueX Collaboration Meeting 11

Three Proposals

5/21/12

• 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.

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 3rd FDC

– May impact tracking badly.

o Proximity focus, mirror less o Primary radiator: 15 mm Freon, n = 1.28o Secondary Radiator: CF4

o Cs-I GEM covers end cap and barrel regiono Immune to magnetic field

GlueX Collaboration Meeting 13

LHCb RHICH-1 Design

5/21/12

• 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

Modification of FDCTwo eight-chamber packagesZERO material: Helium replaces air that mostly compensates for additional materialTHEREFORE: 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

GlueX Collaboration Meeting 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.

5/21/12

GlueX Collaboration Meeting 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.

5/21/12