1. FToF Design and Overview Report CLAS12 ToF System Review 2009 1 Requirement and result driven design, construction, quality assurance, man power, time effort, timeline, and cost estimates FToF Design and Overview Report CLAS12 Time-of-Flight System Review 2009 Jefferson Lab, Newport News, VA Ralf W. Gothe, Evan Phelps, Robert Steiman, and Ye Tian University of South Carolina

2. FToF Design and Overview Report CLAS12 ToF System Review 2009 2 Forward Time-of-Flight Upgrade JLab Designer FTOF Panel 1a FTOF Panel 1b Solenoid 5T CTOF SVT Central Detector DC R1, R2, R3 LTCC PCAL EC HTCC TORUS Forward Detector CLAS12

3. FToF Design and Overview Report CLAS12 ToF System Review 2009 3 Forward Time-of-Flight Upgrade JLab Designer 2 1

4. FToF Design and Overview Report CLAS12 ToF System Review 2009 4 Forward Time-of-Flight Upgrade JLab Designer 2 1a & b Panel 1b

5. FToF Design and Overview Report CLAS12 ToF System Review 2009 5 Forward Time-of-Flight Upgrade JLab Designer Panel 1b

6. FToF Design and Overview Report CLAS12 ToF System Review 2009 6 Forward Time-of-Flight Upgrade JLab Designer Panel 1b

7. FToF Design and Overview Report CLAS12 ToF System Review 2009 7 Forward Time-of-Flight Specifcitions Panel 1b  Hamamatsu R9779: 4.5 in  Electron Tubes 9214A: 7.0 in  No light guides!

8. FToF Design and Overview Report CLAS12 ToF System Review 2009 8 Simulation of Various Light Guides  The plot shows ratio of light that has entered the light guide to the amount that enters the glass envelope of the photomultiplier tube in dependence of the light guide length for two different reflectivities of the wrapping material.  … but penetrating axial magnetic fields cm Gordon Mutchler Reflectivity 0.9 0.7

9. FToF Design and Overview Report CLAS12 ToF System Review 2009 9 Design Requirements Proton-Pion separation up to 5.3 GeV/c Kaon-Pion separation up to 2.6 GeV/c To achieve and an improved timing resolution of  ~ 80 ps is needed Proton-Kaon separation up to 4.5 GeV/c

10. FToF Design and Overview Report CLAS12 ToF System Review 2009 10 The Present Time-of-Flight System 15 cm width (forward angle) 22 cm width (large angle)  0 : Electronics Has to be optimized!  1 : Scintillator and PMT Has to be optimized!  p : Path-Length Variation Has to be optimized! N pe : Number of photoelectrons Has to be increased! N pe increases by 5/2 = (A FTOF6 /A FTOF12 )  (T TOF12 /T TOF6 )

11. FToF Design and Overview Report CLAS12 ToF System Review 2009 11 Design Requirements and Results better than ~ 150 ps for the current FTOF panel better than ~ 95 ps for the new FTOF panel With a resolution for the longest scintillators of and a combined timing resolution of  ~ 80 ps can be accomplished FTOF12 design counter yields  ~ 40 ps (120 cm long) FTOF6 counter yields  = 138 ps (213 cm long) √2/5 BC-404

12. FToF Design and Overview Report CLAS12 ToF System Review 2009 12 Light Attenuation BC-404 with  160 cm (Saint Gobain) but  325 cm (measured) BC-408 with  380 cm (Saint Gobain) but  275 cm (measured) BC-404

13. FToF Design and Overview Report CLAS12 ToF System Review 2009 13  6 cm  6 cm BC-404/BC-408 Scintillators two sides molded and two diamond-tool finished  Hamamatsu R9779 PMTs active voltage divider, anode and dynode, inverter, with  -shielding, will be glued directly onto the masked scintillator end window  Signal and HV Cable RG-174 (BNC) and SCR (SHV) short pigtail, RG-58 (BNC) and RG-59 (SHV) to local sector readout and HV supply  Wrapping aluminized Mylar (scintillator), ligth-tight DuPont TM Tedlar (up to pigtail), black tape (end window mask)  Support Stucture two counters will be taped to a support structure as before (CLAS6)  No Detector Calibration System neither Laser nor LED Current Counter Construction and Design

14. FToF Design and Overview Report CLAS12 ToF System Review 2009 14  Six Centering Tools to center PMTs on scintillator end window during 24-hour curing process  Windmill Support Structure to load horizontally, glue vertically (PMT1), cure, rotate by 180 o, glue vertically (PMT2), cure  Precision Cutter to cut the Tedlar film  Vacuum Station to degas the two-component scintillator glue mixture  Black Box to perform PMT quality assurance in a light-tight environment Construction Tools

15. FToF Design and Overview Report CLAS12 ToF System Review 2009 15  6 cm  6 cm BC-404/BC-408 Scintillators are inspected for damages, inclusions, and refraction index inhomogeneities  Hamamatsu R9779 PMTs are tested for signal integrity, signal-to-noise ratio, gain, HV requirements, and magnetic field shielding  Counter Pre-Check counters are inspected for void-free glued PMT-to-scintillator transition and light tightness, set to final gain-balanced HVs  Counter Full-Check with Three-Bar-Method position dependent and overall time resolutions, effective speed of light, left and right attenuation lengths (BAL and TAL) are programmatically analyzed and automatically stored  Database all acquired information is stored and retraceable Quality Assurance

16. FToF Design and Overview Report CLAS12 ToF System Review 2009 16 Assigned USC Manpower 2009/10  Faculty R.W. Gothe (PI) S. Strauch (CoPI) Ch. Djalali, Y. Ilieva, D. Tedeschi  Post Doc K. Park (09) G. Fedotov ( > 10)  Graduate Students E. Phelps L. Graham (MS) H. Lu R. Steinman (MS) Y. Tian D. Xue  Undergraduate Students J. Giambernadino

17. FToF Design and Overview Report CLAS12 ToF System Review 2009 17 QA PMT(signal integrity, noise, gain, HV, shielding) 384 mh C Scintillators(inspect, glue, inspect void-free bond, wrap)3072 mh QA Detector(light tightness, gain-balanced HVs, DAQ check) 384 mh QA  TOF,, c eff (10h three-bar method run, comprehensive analysis)1152 mh C Pairing (backing structure, storage) 768 mh C Loading (single layer, individually anchored, foam protected) 288 mh C Unloading(storage at JLab) 160 mh C Assembly(assist sector assembly at JLab) 192 mh QA, HV(sector by sector) 120 mh Total6520 mh USC Time and Effort Estimate (0.5h*1S*384*2) (4h*2S*384) (0.5h*2S*384) (3h*1S*384) (2h*2S*384/2) (0.5h*3S*384/2) (10 ’ *5S*384/2) (0.5h*2S*384/2) (10h*2S*6) QA PMT(signal integrity, noise, gain, HV, shielding) 384 mh C Scintillators(inspect, glue, inspect void-free bond, wrap)3072 mh QA Detector(light tightness, gain-balanced HVs, DAQ check) 384 mh QA  TOF,, c eff (10h three-bar method run, comprehensive analysis)1152 mh C Pairing (backing structure, storage) 768 mh C Loading (single layer, individually anchored, foam protected) 288 mh C Unloading(storage at JLab) 160 mh C Assembly(assist sector assembly at JLab) 192 mh QA, HV(sector by sector) 120 mh Total6520 mh

18. FToF Design and Overview Report CLAS12 ToF System Review 2009 18 Procurement 1(PMTs, scintillators, and backing structures)1/10 – 3/10 FY Fabrication 1(PMTs, scintillators, and backing structures)2/10 – 4/10 FY Construction 1(detector assembly at USC)3/10 – 1/12 FY QA 1(concurrent with detector assembly at USC)3/10 – 1/12 FY Procurement 2(PMTs, scintillators, and backing structures)1/11 – 3/11 FY Fabrication 2(PMTs, scintillators, and backing structures)3/11 – 1/12 FY Construction 2(detector assembly at USC)2/12 – 4/13 FY QA 2(concurrent with detector assembly at USC)2/12 – 4/13 FY Procurement 3(cable and sector frames)2/12 – 3/13 FY Construction 3(detector assembly at JLab)4/13 – 2/14 FY QA 3(concurrent with detector assembly at JLab)4/13 – 2/14 FY USC Construction Timeline Estimate

19. FToF Design and Overview Report CLAS12 ToF System Review 2009 19 PMTs(PMT + Inverter)$ 729,300 + Tax Scintillators(Scintillator + Glue)$ 534,800 + Tax Shielding(  -metal + active)$ 75,800 + Tax Wrapping(Tedlar + Mylar + Tape + Foam)$ 18,700 + Tax Cable(SHV + BNC + Adapter)$ 136,500 + Tax Tools(Center + Windmill + Cutter + Degas + Black Box)$ 12,800 + Tax Transportation(Packing + Shipping)$ 11,550 + Tax Post Doc(Salary + Fringe)$ 87,150 Students(Man-hours * Wage + Accommodation + Travel)$ 88,700 Total$1,695,300 + Tax Current Cost Estimate ($880+$55)*(384*2+12) ($800/120cm*410cm/2*384) ($100+$100)*384 ($11200+$3000+$3000+$1500) ($54524+$47616+$34360) ($1800+$8000+$1500+$1000+$500) ($1050+$5000*2) ($58097/2*3) (6520h*$12.13+$4612+$5000) PMTs(PMT + Inverter)$ 729,300 + Tax Scintillators(Scintillator + Glue)$ 534,800 + Tax Shielding(  -metal + active)$ 75,800 + Tax Wrapping(Tedlar + Mylar + Tape + Foam)$ 18,700 + Tax Cable(SHV + BNC + Adapter)$ 136,500 + Tax Tools(Center + Windmill + Cutter + Degas + Black Box)$ 12,800 + Tax Transportation(Packing + Shipping)$ 11,550 + Tax Post Doc(Salary + Fringe)$ 87,150 Students(Man-hours * Wage + Accommodation + Travel)$ 88,700 Total$1,695,300 + Tax

20. FToF Design and Overview Report CLAS12 ToF System Review 2009 20 Supplement

21. FToF Design and Overview Report CLAS12 ToF System Review 2009 21 Acquisitions by 2009  Electronics: NIM (LED, CFD), VME (TDCs), HV (CAEN), Readout (LabView)  Oscilloscopes: DPO 7254 (fast), 1 analog and 2 digital (slow)  PMTs: 2 * 9214 (Electron Tubes), 2 * R9779 (Hamamatsu), 2 * XP2020, 2 * XP2020UR, 2 * XP20Y0, 2 * XP20D0 (Photonis)  Voltage Deviders: 2 * C638A (Electron Tubes), 2 * R9779 (Hamamatsu), 2 * VD124KT, 2 * VD127KT, 2 * XP20Y0, 2 * XP20D0 (Photonis)  Scintillators: EJ 204 (50, 100, 250 cm), EJ 200 (50, 100, 250, 400 cm) (ELJEN), BC 404 (20, 50 cm), BC 408 (50, 150, 400 cm) (Saint-Gobain)  Light Guides: 2 * BC 802 (UV blind), 2 * BC 800 (Saint-Gobain)  Wrapping: Tedlar Film, Aluminized Mylar Film, VM2000, Tape,  -Shielding  Others: 2 * CLAS ToF Counters, Detector Lab, Assembly Hall, Infrastructure

22. FToF Design and Overview Report CLAS12 ToF System Review 2009 22 Solenoid (ITK) - Magnetic field distribution The field maps. A – General view, the marks are field level (T) B – Field Homogeneity, the marks are non- homogeneity values related to the central field. C – Magnetic flux lines, the marks are magnetic flux confined inside the corresponding surface of revolution (Wb). D – Stray field, the marks are field level (T). The field homogeneity in a polarized target volume is better than 2.14E-5 AB CD