GlueX: Plans for Hall D and Equipment

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1 GlueX: Plans for Hall D and Equipment Elton S. Smith, Jefferson Lab Introduction Photon beamline Detector capabilities Event reconstruction Elton S. Smith 1

2 Overview Hall D is a new experimental hall to be located on the east side of the north linac The project includes the design, construction and commissioning of the photon beam and experimental equipment in Hall D. The detector incorporates existing hardware Solenoid magnet used for the LASS experiment at SLAC and the MEGA experiment at LANL Lead glass used in BNL E852 The GlueX physics collaboration (approximately 70 people from 25 institutions) has been active for seven years The GlueX collaboration is leading the detector R&D and conceptual design efforts in Hall D. 2

3 Physics goals and key features The physics goal of GlueX is to map the spectrum of hybrid mesons starting with those with the unique signature of exotic J PC. Identifying J PC requires an amplitude analysis which in turn requires linearly polarized photons detector with excellent acceptance and resolution sensitivity to a wide variety of decay modes Final states include photons and charged particles and require particle identification. Hermetic detector with large acceptance for charged and neutral particles In addition, sensitivity to hybrid masses up to 2.5 GeV requires 9 GeV photons which will be produced using coherent bremsstrahlung from 12 GeV electrons. 3

4 Architect s rendering of Hall D complex Hall D Counting House Cryo Plant Service Buildings Status: 35% by September Land transfer by October Expect 60% by December 4

5 Photon beam and experimental area North linac Tagger area Hall D East arc Electron Beam dump Radiator 75 m Photon Beam dump Electron beam Tagger Area Collimator Coherent Bremsstrahlung photon beam Solenoid- Based detector Experimental Hall D Top View 5

6 Hall D/GlueX Reviews The experiment has sought out expert advice by requesting external reviews Cassel Committee (Dec 1999) David Cassel (chair), Frank Close, John Domingo, William Dunwoodie, Donald Geesaman, David Hitlin, Martin Olsson, Glenn Young GlueX Electronics (Jul 2003) John Domingo, Andy Lankford (chair), Glenn Young GlueX Detector Review (Oct 2004) Mike Albrow, Jim Alexander (chair), William Dunwoodie, Bernhard Mecking Solenoid Assessment (Nov 2004) John Alcorn, Robert Kephart (chair), Claus Rode Review of Tagging Spectrometer and Photon Beamline (Jan 2006) Juergen Ahrens (chair), Bernhard Mecking, Alan Nathan The collaboration has responded to issues raised by these committees and developed the present solid foundation for further design and construction Note: GlueX has also been reviewed by PAC23 (Jan 2003), PAC27 (Jan 2005) and the DOE Science Review (April 2005) 6

7 Coherent Bremsstrahlung 12 GeV electron beam This technique provides requisite energy, flux and polarization flux Incoherent & coherent spectrum 40% polarization in peak electrons in photons out collimated spectrometer (two magnets) diamond crystal tagged (0.1% resolution) photon energy (GeV) 7

Project Review completed Review of Tagging Spectrometer and Photon Beamline (January 2006) Juergen Ahrens (chair), Bernhard Mecking, Alan Nathan Complete geometry model in HDGeant with built-in

8 Project Review completed Review of Tagging Spectrometer and Photon Beamline (January 2006) Juergen Ahrens (chair), Bernhard Mecking, Alan Nathan Complete geometry model in HDGeant with built-in coherent bremsstrahlung generator The major sources of background are in the tagger area (not the electron beam dump). Magnetic field map from TOSCA Backgrounds in the tagger area are tolerable. the conceptual design of the tagger magnet and the hodoscope systems are well motivated by the Hall D physics goals, and are adequate to achieve those goals. The committee is also convinced that the design parameters of the photon beamline are optimized to achieve the highest possible linear polarization at the envisioned high tagging rates. 8

9 Hall D Detector Hermetic detection of charged and neutral particles Tagger Spectrometer (Upstream) 9

10 Hall D Scope: Detector Design Parameters Capability Quantity Range Charged particles Coverage 1 o < θ < 170 o Momentum Resolution (5 o -140 o ) σ p /p = 1 2% Position resolution σ ~ µm de/dx measurements 20 < θ < 140 o Time-of-flight measurements σ t < 60 ps Cerenkov and π/k separation θ < 14 o Barrel time resolution σ t < ( / E) ps Photon detection Energy measurements 2 < θ < 120 o Veto capability θ > 120 o LGD energy resolution (E > 100 MeV) σ E /E = ( / E)% Barrel energy resolution (E > 20 MeV) σ E /E = (2 + 5/ E)% LGD position resolution σ x,y, ~ 1 cm Barrel position resolution σ z ~ 4 cm DAQ/trigger Level khz Level 3 event rate to tape 15 khz Data rate 100 MB/s Electronics Fully pipelined Flash ADCs, multi-hit TDCs

refurbishing in October 2003 All coils have

11 Solenoid Superconducting 2.24 T solenoid Built and operated at SLAC for the LASS experiment Moved to Los Alamos for use in the MEGA experiment Moved to IUCF for refurbishing in October 2003 All coils have been refurbished Short in coil 3 fixed Short in coil 1 scheduled for next year 11

12 Tracking detectors Central DC Cylindrical straw tube chamber 23 layers from 14cm to 58cm Additional layers at r < 14cm 6 o stereo layers σ rφ ~ 150µm, σ z ~2mm de/dx for p < 450 MeV/c One fourth full-scale prototype has been completed and is under test. Forward DC Four packages of 6 layers of drift wires and orthogonal cathode strips σ xy ~150µm Active close to the beam line Extensive tests of small prototype completed. p/p ~ 2% p < 3 GeV FDC CDC anode wires 2,856 3,240 cathodes strips 11,424 12

Prototyping of central drift chambers Carnegie

procedures determined Kapton chosen for straw

collaborating with U Penn to develop an ASIC

Testing has begun using cosmic-rays and Struck

13 Prototyping of central drift chambers Carnegie Mellon Mechanical assembly geometry and stringing procedures determined Kapton chosen for straw tubes On-board electronics U Alberta is collaborating with U Penn to develop an ASIC preamp design Matching signals to FADC electronics Testing has begun using cosmic-rays and Struck 200MHz FADC Gas system Integration of gas system and electronics for prototype 13

Prototyping of forward drift chambers Mechanical

cathode planes flat and stay under our material

electronics Cathodes are being tested with Struck

14 Prototyping of forward drift chambers Mechanical assembly Techniques are under development to keep cathode planes flat and stay under our material thickness budget On-board electronics U Alberta is collaborating with U Penn to develop an ASIC preamp design Matching signals to readout electronics Cathodes are being tested with Struck FADCs and anode wire times are read with F1 TDCs Ohio University 14

15 Calorimetry Upstream Photon Veto Photons exiting upstream ~20MeV Eγ 300 MeV UPV Barrel calorimeter Lead - scifiber sandwich 4m long cylinder σ E /E / E ~20MeV Eγ ~ 3 GeV σ t ( / E) ps z-position of shower time-of-flight for charged particles Barrel Expected π o and η resolutions Forward calorimeter Existing lead glass detector ~2800 blocks σ E /E / E ~ 100 MeV Eγ 8 GeV Pb Glass 15

Barrel calorimeter beam test Beam test in Hall B (downstream alcove) September 22 30 Electron

MeV energy and time response to photons at large incident angles (between 45 and 80 degrees to

16 Barrel calorimeter beam test Beam test in Hall B (downstream alcove) September Electron beam energy 687 MeV Purpose of test is to measure energy and time resolution for 135 < Eγ < 653 MeV energy and time response to photons at large incident angles (between 45 and 80 degrees to normal) response as a function of impact position on the calorimeter Barrel U. of Regina, Indiana U. 16

17 Particle Identification Cerenkov detector π K p separation DIRC or Gas Cerenkov Active R&D effort at SLAC to optimize DIRC axis Nominal design is for gas Cerenkov Time-of-flight Forward TOF σ t 60 ps BCAL σ t ( / E) ps Multi-anode PMT Focusing mirror de/dx information The CDC will do de/dx for p < 450 MeV/c The FDC may do de/dx Babar DIRC with compact mirror design 17

Digitizer Digital Pipeline Flash ADC Elton S.

18 Electronics Front-ends fully pipelined Every event block Recent R&D Trigger Every event Analog Data Front End Digitizer Digital Pipeline Flash ADC Elton S. Smith FE/DAQ Interface Event Block Buffers To ROC Pipeline TDC PAC30 August 21,

19 Institutional Responsibilities The GlueX collaboration has designed and optimized the detector to study gluonic excitations. Many university groups have contributed to the R&D and development of major subsystems. Solenoid JLab, IU Cyclotron Facility Detectors Tracking Calorimetry PID Computing Electronics Beamline Infrastructure Carnegie Mellon, Florida International, Ohio Alberta, Athens, Florida State, Indiana, Regina Indiana, Inst for High Energy Physics (Protvino), Oak Ridge, Tennessee Carnegie Mellon, Connecticut Indiana, JLab, Regina Alberta, Christopher Newport, Guanajuato, Indiana, IU Cyclotron Facility, JLab Catholic, Connecticut, Glasgow JLab 19

20 Reconstruction for global design decisions Extensive acceptance and resolution studies have been performed using HDFast, a parametric Monte Carlo which included the Hall D geometry and materials. Continue development of full detector simulation and reconstruction with the goal of validating that detector designs meet physics performance for Halls B and D Project Status Review (June 2006) Goals Develop realistic pattern recognition and reconstruction software Use realistic simulations to make design choices Status A framework for the reconstruction is in place Track pattern recognition has been developed using GEANT hits and random backgrounds Momentum is estimated by assuming helical trajectories. In progress: momentum reconstruction in non-uniform field In progress: reconstruction of photons in neutral detectors 20

21 Simulation of four-track event Pattern recognition algorithm applied to full GEANT simulation of event, smeared DC hits, and random background. General track fitting programs are under development. 21

22 Example: studies of tracking efficiency Momentum (GeV) Scattering angle (radians) General track fitting programs need to be developed and optimized. 22

23 Summary and Conclusions The GlueX detector has been optimized to carry out a longterm and extensive program of Meson Spectroscopy. The detector is unique in having been designed from the ground up to be able to carry out amplitude analysis. The experiment continues to seek advice from outside experts and is responding to their comments and suggestions. Hall D and the GlueX collaboration is engaged in an active research program to clarify technical issues and optimize the overall cost and schedule of the project. 23

24 BACKUP 24

25 Detector Systems Tracking Calorimetry Particle Identification 25

26 Plan view of Hall D 26

27 Proposed FY08 Long Lead Procurement The 12 GeV project has proposed that the procurement for a third of the total order of fibers for the barrel calorimeter (~$1M) be considered a long lead item for FY08. Key issues which motivate this proposal include Significant reduction in schedule risk will result from procuring the fibers as a long-lead item since a delay in ordering fibers will directly affect the completion time of the Hall D detector. Significant Canadian contributions to the project may be leveraged if fibers are ordered as a long-lead item. 27

28 Hall D Milestones for FY07 Decision on readout for barrel calorimeter (Rec #27) Drift chamber design requirements finalized 28

29 New Compact Mirror Focusing Design - use quartz plates instead of bars window mirror Beam line Multi-anode PMT Focusing mirror 63.0 cm 10.2cm Magnetic z ~ 450 cm 250cm Tank filled with Kamland oil 29

30 Schedule for barrel calorimeter construction Fabrication at U. of Regina Long-lead Fabrication at U. of Alberta 30

of Connecticut IHEP (Protvino) the conceptual design of the tagger magnet and the hodoscope systems are well motivated by the Hall D physics

31 Project review completed Review of Tagging Spectrometer and Photon Beamline (January 2006) Juergen Ahrens (chair), Bernhard Mecking, Alan Nathan University of Glasgow Catholic U. of America U. of Connecticut IHEP (Protvino) the conceptual design of the tagger magnet and the hodoscope systems are well motivated by the Hall D physics goals, and are adequate to achieve those goals. The committee is also convinced that the design parameters of the photon beamline are optimized to achieve the highest possible linear polarization at the envisioned high tagging rates. 31

32 Prototyping of Flash ADCs Builds on developments for present program FADC 250 MHz is being developed for current experiments 12-GeV specific work is the creation of energy sums for Hall D trigger and addition of high-speed links needed for transfer of energy-summed data Specific goals Develop VXS backplane serial links for data transfer Design and fabricate a v1 prototype for the energy-sum board which can serve four payload FADC boards Status VXS serial links have been verified Energy sum board (v1) has been designed and is being fabricated 6 GeV FADC 250 MHz 10/12 bit VME64X VXS 17-19/crate Hall D Energy Sum Switch SlotA VXS 1/crate Christopher Newport University, Indiana University, Jefferson Lab 32

33 Backgrounds from electron beam dump Counts in microscope Counts in broad-band + All backgrounds + Dump rates x All backgrounds + Dump rates x 1000 Energy (MeV) Energy (MeV) The major sources of background are in the tagger area proper (not in the electron beam downstream). 33

34 Acceptance: high and uniform over PWA angles Extensive acceptance and resolution studies have been performed using HDFast, a parametric Monte Carlo which included the Hall D geometry and materials. Acceptance ε γ ~0.98 ε π ~0.99 cosθ GJ φ GJ 34

Particle Identification Time-of-flight Forward TOF σ t 60 ps BCAL σ t (150 + 50/ E) ps de/dx information The CDC will do de/dx for p < 450 MeV/c The

35 Particle Identification Time-of-flight Forward TOF σ t 60 ps BCAL σ t ( / E) ps de/dx information The CDC will do de/dx for p < 450 MeV/c The FDC may do de/dx axis central Cerenkov detector π K p separation DIRC or Gas Cerenkov Active R&D effort at SLAC to optimize DIRC very forward forward 35

Search for Gluonic Excitations with GlueX at Jefferson Lab

Search for Gluonic Excitations with GlueX at Jefferson Lab Volker Credé Florida State University Tallahassee, FL The Structure and Dynamics of Hadrons Hirschegg, 01/19/2007 Outline 1 2 3 4 Outline 1 2