1. The GlueX Detector in Hall-D at Jefferson Lab February 16, 2010 David Lawrence, Jefferson Lab (for Curtis A. Meyer, Carnegie Mellon University) July 7, 2009GlueX - ACTS 2009 - David Lawrence1

2. Exotic Hybrid Mesons and the choice of photoproduction July 7, 2009GlueX - ACTS 2009 - David Lawrence Conventional meson has quantum numbers determined only by constituent quarks Hybrid meson has angular momentum contribution from “the glue” J PC P = (-1) L+1 C = (-1) L+S J PC = 0 -+, 0 ++, 1 ++ 1 +-, 2 -+, 2 ++ J PC = 0 -+, 0 ++, 0 +- 1 ++, 1 -+, 1 +- 2 -+, 2 ++, 2 +- “exotic” states 2 spins not aligned (S=0) spins aligned (S=1) Expect higher exotic hybrid production rate using photon beam J. Dudek et al., PRD 79 (2009) Compute radiative decays in charmonium to normal and hybrid mesons. Rates are comparable. Work currently underway to compute the same for light quarks J PC = 0 -+, 0 ++, 0 +- 1 ++, 1 -+, 1 +- 2 -+, 2 ++, 2 +-

3. The normal mesons are built up from a “quark- antiquark pair” with a “ground-state” flux tube. Gluonic Excitations provide an experimental measurement of the excited QCD potential July 7, 2009GlueX - ACTS 2009 - David Lawrence3 QCD Potential

4. 4 Lattice QCD predicts exotics ~2GeV/c 2.  3 nonets of exotic-quantum number states.  Decays expected to 4-5 pions with photons. GlueX has been designed to detect these.  Large acceptance for these final states.  Good resolutions.  Partial Wave Analysis tools to carry out analysis. QCD Potential  Excited glue yields hybrid nonets  Many of the hybrid nonets have exotic quantum numbers

5. 6 GeV CEBAF 11 GeV CEBAF CHL-2 12 GeV CEBAF Upgrade magnets and power supplies Two 0.6 GV linacs Two 1.1GV linacs Enhanced capabilities in existing Halls The JLab 12GeV Upgrade July 7, 2009GlueX - ACTS 2009 - David Lawrence5

6. The GlueX Detector July 7, 2009GlueX - ACTS 2009 - David Lawrence TOF time of flight SC start counter 2.2T superconducting solenoidal magnet Fixed target (LH 2 ) 10 8 tagged  /s (8.4-9.0GeV) hermetic 2.2 Tesla Solenoid Calorimetry Barrel Calorimeter (lead, fiber sandwich) Forward Calorimeter (lead-glass blocks) PID Time of Flight wall (scintillators) Start counter Barrel Calorimeter Charged particle tracking Central drift chamber (straw tube) Forward drift chamber (cathode strip) 6

7. 7 Expect some occupancy late in 2010 Hall D: February 2010

8. 8 48-module BCAL at University of Regina Completing modules 3 and 4. First shipments to JLab in April Detector Construction (2009/2010)

9. 9 Lead-glass Forward Calorimeter at Indiana University Contract for construction in place soon. Work starting spring 2010 Central Drift Chamber at Carnegie Mellon Contract for construction in place soon. Work starting spring 2010 More contracts starting in 2011 and 2010 Detector Construction (2009/2010)

10. 10 Hall-D Groundbreaking  The 12 GeV upgrade of Jefferson Lab is currently under construction  Construction of Hall-D broke ground in April 2009  Construction of the GlueX detector has started Current plans call for the first beam in Hall-D/GlueX in late 2014 The GlueX Detector in Hall-D

11. 11  The GlueX Detector and Hall-D at JLab are under construction.  We expect to start the search for exotic mesons in 2014.  There are other physics programs that are starting to materialize for GlueX PrimEx (Primakoff Effect) on the eta approved in 2010. A workshop on these activities in 2010. Summary

12. Backup Slides July 7, 2009GlueX - ACTS 2009 - David Lawrence12

13. The GlueX Experiment July 7, 2009GlueX - ACTS 2009 - David Lawrence 9GeV linearly polarized hybrid meson detectable final state (mixed charged and neutral) Goal : map the spectrum of exotic hybrid mesons Method : Photo-produce hybrids off proton target and identify the quantum states using Partial Wave Analysis of decay product distributions 13

14. The GlueX Detector July 7, 2009GlueX - ACTS 2009 - David Lawrence David Lawrence (JLab) Electron beam accelerator continuous-wave (1497MHz, 2ns bunch structure in halls) Polarized electron beam Upgrading to 12GeV (from 6GeV) 70  A max @ 12Gev (200  A max @ 6GeV) Existing experimental halls A, B, C Future Hall-D site 14

15. Hall-D Complex at Jefferson Lab July 7, 2009GlueX - ACTS 2009 - David Lawrence ~100 meters electron beam Construction has recently begun and will be completed Fall 2011. (Buildings only, detectors will follow) 15

16. The Photon Tagger July 7, 2009GlueX - ACTS 2009 - David Lawrence 1.5T dipole magnet 12m long vacuum chamber e-e- 20  m diamond radiator The photon carries some energy away leaving the electron with less so that it gets bent more by the magnetic field 16 Some electrons undergo bremstrahlung (“breaking radiation”) and create a photon while passing through the diamond Most electrons don’t interact with the diamond and get bent right into the beam dump These electrons pass through detectors lining the side of the vacuum chamber. Which detector gets hit tells us how much energy the electron was left with (and therefore how much was given up to the photon!) e-e- e-e- photon The experiment will ultimately see 100 million tagged photons every second impinging on our liquid Hydrogen target (only a tiny fraction will interact).

17. Calorimetry July 7, 2009GlueX - ACTS 2009 - David Lawrence Barrel Calorimeter: 191 layer Pb-scintillating fiber sandwich (15.5X o ) 12.5% sampling fraction 1152 + 192 = 1344 readout sections/end  E /E= (5.54/√E 1.6) %  z = 5mm/√E  t = 74ps/√E 33ps angular coverage 11 o <  < 120 o Forward Calorimeter: 2800 F8-00 and F108 (center) Pb-glass blocks 4cm x 4cm x 45cm  E /E= (5.7/√E 2.0) %  xy = 6.4mm/√E angular coverage 2 o <  < 11 o 17

18. Charged Particle Tracking Chambers July 7, 2009GlueX - ACTS 2009 - David Lawrence Central Drift Chamber: 3522 straw tubes (1.6cm diameter) 12 axial layers, 16 stereo layers (6 o ) dE/dx for p < 450 MeV/c  r = 150  m angular coverage 6 o <  <155 o Forward Drift Chamber: 4 packages, 6 planes/package, 96 wires/plane (2304 sense wires) cathode strip readout (48 planes x 216 strips/plane = 10,368 strips)  r = ~200  m perpendicular to wire (drift time)  s = ~200  m along wire (cathode strips) angular coverage 1 o <  <30 o  p /p : 1.5 - 3.0%   : 1 - 8 mrad   : 2 – 3 mrad 18

19. A single  p   pb 1  event July 7, 2009GlueX - ACTS 2009 - David Lawrence Final state: p  +  +  -  -  o 19

20.  diff (ps) Particle ID July 7, 2009GlueX - ACTS 2009 - David Lawrence  p separation <450MeV/c  K separation <275MeV/c Barrel Calorimeter Forward TOF  diff (ns) ~200 ps ~80 ps CDC dE/dx 40 scintillators 300 ps (w/tracking) Used for start-up Start Counter Particle ID is done primarily through time of flight with some help from dE/dx in chambers. Space is left in design for a future PID detector. Beam Test DataExpected Separation 20

21. July 7, 2009GlueX - ACTS 2009 - David Lawrence Locations of Primary Particle Interactions FDC FCAL CDC BCAL 21

22. July 7, 2009GlueX - ACTS 2009 - David Lawrence JANA Multi-threaded event processing framework Rate scalability Modular Multi-threaded 22

23. July 7, 2009GlueX - ACTS 2009 - David Lawrence Page 23 CapabilityQuantityRange Charged particles Coverage 1 o <  < 160 o Momentum Resolution (5 o -140 o )  p /p = 1 − 3% Position resolution  ~ 150-200  m dE/dx measurements 20 <  < 160 o Time-of-flight measurements  ToF ~ 60 ps;  BCal ~ 200ps Barrel time resolution  t  < (74 /√E 33) ps Photon detection Energy measurements 2 o <  < 120 o LGD energy resolution (E > 60 MeV)  E /E = (5.7/√E 2.0)% Barrel energy resolution (E > 60 MeV)  E /E =(5.54/√E 1.6)% LGD position resolution  x,y, ~ 0. 64 cm/√E Barrel position resolution  z ~ 0.5cm /√E DAQ/trigger Level 1 < 200 kHz Level 3 event rate to tape ~ 15 kHz Data rate 300 MB/s Electronics Fully pipelined 250 / 125 MHz fADCs, TDCs Photon Flux Initial: 10 7  /s Final: 10 8  /s Hall D: Detector Design Parameters 23

24. July 7, 2009 A 3-Track Event ~20 space points per track GlueX - ACTS 2009 - David Lawrence24

25. July 7, 2009GlueX - ACTS 2009 - David Lawrence Inhomogeneous Magnetic Field Map (  - symmetric) 25

26. 26 F Future The GlueX Experiment