Hall D Report. E.Chudakov 1. PAC43, July Hall D Group Leader. E.Chudakov PAC43, July 2015 Hall D Report 1

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1 E.Chudakov PAC43, July 2015 Hall D Report 1 Hall D Report E.Chudakov 1 1 Hall D Group Leader PAC43, July 2015

2 E.Chudakov PAC43, July 2015 Hall D Report 2 Outline 1 Physics program 2 Collaboration and staff 3 Apparatus and main specifications 4 Status of commissioning with beam

3 Physics Program E.Chudakov PAC43, July 2015 Hall D Report 3 Proposal/ Sta- Title Beam PAC experiment tus days # E A Mapping the Spectrum of Light Quark Mesons and Gluonic Excitations with Linearly Polarized Photons E A- A Precision Measurement of the η Radiative Decay Width via the Primakoff Effect E A An initial study of hadron decays to strange final states with GlueX in Hall D E A- Measuring the Charged Pion Polarizability in the γγ π + π Reaction C A A study of meson and baryon decays to strange final states with GlueX in Hall D C C2 Eta Decays with Emphasis on Rare Neutral (130) 42 Modes: The JLab Eta Factory Exper- iment (JEF) partly concurrent with GlueX (η 3π) LOI Physics with secondary KL beam 43 LOI ω-production on nuclei 43

4 The Hall D/GlueX collaboration E.Chudakov PAC43, July 2015 Hall D Report 4 GlueX Collaboration: 21 institutions; about 110 scientists Hall D Scientific Staff: 13 staff scientist, 1 postdoc fellow Applied recently to joining GlueX: George Washington University Mississippi State University GSI

5 Beamline Tagger Magnet Hodoscope (TAGH), µ-scope (TAHM) γ-polarimeter 12 GeV e beam µa 20 µm diamond: coherent <25 µrad Collimation r <1.8 mm at 80 m Coherent peak GeV P 40% 2.2 µa 100 MHz γ Energy/polarization measured: Tagger spectrometer σe/e 0.1% Pair spectrometer: spectrum σp/p 5% tagged collimated E.Chudakov PAC43, July 2015 Hall D Report 5 E γ GeV GeV 100 MHz P 40%

6 Hall D/GlueX Spectrometer and DAQ E.Chudakov PAC43, July 2015 Hall D Report 6 GlueX Resolutions h ± : σp/p 1 3% γ: σe/e 6%/ E 2% Acceptance 1 < θ < 120 diamond wafer electron beam tagger magnet photon beam tagger to detector distance is not to scale barrel calorimeter target 30 cm LH 2 electron beam B = 2.0 T time-of -flight superconducting magnet forward calorimeter central drift chamber forward drift chambers Detectors CDC, FDC BCAL, FCAL TOF, ST Plans to add 2017 L Cherenkov Photoproduction γp 15 khz for a 100 MHz beam Beam 10 MHz/GeV: inclusive trigger 20 khz DAQ tape Beam 100 MHz/GeV: inclusive trigger 200 khz DAQ L3 farm tape

7 E.Chudakov PAC43, July 2015 Hall D Report 7 Commissioning Status Runs with beam: Fall GeV beam: beam commissioning and detector checkout Spring GeV beam: 1 week - commissioning continued All equipment for GlueX-I has been commissioned at some level! Still to be installed/replaced/commissioned: Solenoid: optimize the running current. Solenoid worked for 3 weeks at 1200 A, but quenched after 1 day of running at 1300A. The issue will be addressed by a review on Jul 14. Tagger microscope: about 30% of the fibers have low efficiency - they will be replaced in Thin diamond radiators for the physics running (20 µm thick) still to be manufactured and installed (50 µm thick sample used).

8 Coherent Bremsstrahlung E.Chudakov PAC43, July 2015 Hall D Report 8 Old diamonds 50 and 100 µm thick Both diamonds were aligned and produced coherent radiation! Tagger, normalized to incoherent spectra Pair Spectrometer

9 Event Display E.Chudakov PAC43, July 2015 Hall D Report 9 2 positive tracks 1 negative track Hits in FDC, CDC, BCAL, FCAL. TOF

10 Track Reconstruction in Drift Chambers E.Chudakov PAC43, July 2015 Hall D Report 10 Alignment, calibration: in progress FDC: Resolution 7 Field-off Empty alignment target reconstruction Resolution Distance between entrance and exit windows of target = 29.9 cm wires: (C. Keith) 160 µm Window FDC - thickness tracks from = thecm, target material=kapton cathode: 250 µm Empty target contains H CDC - cosmics 2 gas at 33 psia and 30 K in progress Positions of chambers in XML set according to survey results Empty LH 2 Target: thin windows σ Z 4 mm Z, cm σ, µm Require doca < 1 cm, r<2 mm Measured distance between windows = 29.28±0.01 cm Run 2931 Per-straw Efficiency CDC efficiency Target center: Survey: z= cm Measured: z=63.17 cm Efficiency Efficiency 0.95% Resolution 200 µm Distance to wire, mm Distance to wire, cm

11 After a few calibration Spring iterations 2015 Fall track skim run > 1770 BCAL EM calorimetry: Calibration using π mass all events all field ON runs FCAL 36,000 π 0 18,000 π 0 Calibration Gaus+pol5 withfit π well advanced; π width is 1.15 of the specs Will McGinley Gluex Collaboration Meeting 5/12/15 M. R. Shepherd GlueX Collaboration Meeting May 12, more statistics needed π width is 1.5 of the specs Data analysis - work in progress Issues with a few % of the CW bases E.Chudakov PAC43, July 2015 Hall D Report 11

12 E.Chudakov PAC43, July 2015 Hall D Report 12! Can identify π/k/p with TOF PID β 1 π + 0.8! Good tracks, hypothesis w/ best tracking FOM, 2 tracks chose RF! monitoring_hists, monitoring webpage: RECO: TOF1 + e + - TOF q e TOF q Entries β 1 π 0.8 Entries p K p (GeV/c) 0.4 K p (GeV/c) ~No RF mismatch with Combo DEventRFBunch Paul Mattione GlueX Physics Meeting June 29, 2015 RF Mismatch 10 1

13 Event Reconstruction and Signals Observed 2 γ p p π γ p p ω Events / 20 MeV/c 2 M γγ (GeV/c ) γ p p π π 200 Spring 2015 Commissioning γp pπ + π - π π + π - π 0 Invariant Mass (GeV/c ) E.Chudakov PAC43, July 2015 Hall D Report 13 2 M γγ (GeV/c ) 2 Events / 20 MeV/c

14 Physics With Linearly Polarized Beam E.Chudakov PAC43, July 2015 Hall D Report 14 Polarized ρ Production with the Hall D Photon Beam Events 100 Spring 2015 Commissioning (a few hours of beam) p! 0 p! + p Events Diamond Amorphous Angle Between Polarization and Decay Planes: ψ (deg.) Energy of Beam with Different Radiators for γp ρp Events Spring 2015 Commissioning (a few hours of beam) coherent bremsstrahlung peak has high degree of linear polarization Diamond Amorphous Energy of Beam Photon (GeV) dσ dψ γ ψ (1 + P cos 2ψ) ρ Decay Plane ρ p π + Photon Beam Polarization Plane Polarization P is preserved in ρ production. π p

15 Outlook E.Chudakov PAC43, July 2015 Hall D Report 15 Program for the next run (12 GeV?) Find a safe current for the solenoid More data for calorimeter calibration Build and install 20 µm-thick diamonds Stable beam position - commissioning of the Fast Feedback system (accelerator) Commissioning of the triple polarimeter and total absorption counter DAQ: aim at 5-10 khz with small dead time Trigger: continue tuning and optimization

16 Backup E.Chudakov PAC43, July 2015 Hall D Report 16

17 DAQ E.Chudakov PAC43, July 2015 Hall D Report 17 Specs: GlueX-I: DAQ 20 khz 300 MB/s tape GlueX-II: DAQ 100 khz 1500 MB/s L3 20 khz tape Many issues solved, still a way to go: CODA: hard to start, networking issues Firmware: FADC-125MHz, TDC CAEN block/buffer level > 1 - First version came in not yet stable Long events (low thresholds, noise issues) Spring 2015 status: Stable at buffer/block level=1 3 khz at 50% live time, 200 MB/s Tests at buffer=4/block=40 30 khz at 97% live time, 600 MB/s still unstable, crashes in a minute Work in progress

18 Coherent Bremsstrahlung and Beam Polarization E.Chudakov PAC43, July 2015 Hall D Report 18 Photon spectrum calculated polarization Triple Polarimetry: First results