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X Ray Transport, Optics, and Diagnostics Overview

X Ray Transport, Optics, and Diagnostics Overview. FAC Photon Topical Oct. 27, 2005.

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X Ray Transport, Optics, and Diagnostics Overview

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  1. X Ray Transport, Optics, and Diagnostics Overview FAC Photon Topical Oct. 27, 2005 This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48.Work supported in part by the DOE Contract DE-AC02-76SF00515. This work was performed in support of the LCLS project at SLAC.

  2. Outline XTOD Configuration X-Ray Beam Conditioning & Diagnostics Goals XTOD Interfaces Upstream FEE Instruments Mechanical & Vacuum XTOD Work Plan Technical Documents, Summary

  3. The FEE Will House the Majority of XTOD Diagnostics and Beam Conditioning Systems Slit Diagnostics Package Be Mirrors 2 & 3 Solid Attenuator Collimator 1 Collimator 2 Fast close valve Gas Attenuator Ion Chamber SiC Mirror 1 Ion Chamber Diagnostics Package SiC Mirror 2

  4. The FEE Instruments Will Be Used to Characterize and Monitor the Performance of the LCLS Beam Start of Experimental Hutches Windowless Ion Chamber 5 mm diameter collimators Muon Shield DiagnosticPackage Spectrometer / Indirect Imager Slit; Fixed Mask Solid Attenuator Total Energy Calorimeter Gas Attenuator e- WFOV Direct Imager FEL Offset mirror system Fast Valve Diagnostic Package Windowless Ion Chamber

  5. Experimental Halls and Tunnel are Comprised Primarily of Transport Systems and Imagers FEH TUNNEL Hutch 2 Flipper Mirror Direct Imager, CD4 Direct Imager Beam Tube, 4.00” OD X .083” W X 120” L NEH Ion Pump Offset Support Turbo Pump Offset Support Flex Support

  6. Gas and Solids Attenuators Can Attenuate the FEL up to 4 Orders of Magnitude Solid Attenuator 256 Attenuation Levels * For a transmission of 10-4 Gas Attenuator Use Gas Use Solids

  7. XTOD Redundant Commissioning Instrumentation

  8. FEL Offset System Has Been Incorporated in the XTOD Plan • Baseline cost & schedule have been defined • The FEE layout has been modified • Radiation Physics analysis has defined critical components (e.g, collimators, shielding) • Development Schedule • Determine mirror and other system specifications • Produce concept and corresponding engineering specification • Complete conceptual engineering design

  9. XTOD Interfaces Have Been Defined • XTOD to Linac (1.1-504) • Vacuum, fluid interfaces • Mechanical Interfaces • Control Signals, electrical interfaces • Radiation & other environmental issues • XTOD to XES (1.1-507) • Vacuum & Mechanical interfaces for PPS • Control Signals • XTOD to Conventional Facilities (1.5-108) • HVAC ( thermal , humidity, gas supplies, exhaust systems) • Mechanical, vibration • Electrical: Power, cable trays,communications

  10. Fast and Slow Valve Specifications • Fast Valve • VAT Series 77 Flap Shutter with Pneumatic Actuator • Closes to less than 30 mTorr*L/s within 15 ms • Opens to full size of beam pipe • 2,000 cycles to first service • Slow Valve • VAT Series 48 All Metal Gate Valve • Seals within 3 seconds • 20,000 cycles to first service • Controls • VAT VF-2 Controller • VAT High Vacuum Sensor • EPICS Compatible • Meets or exceeds all requirements

  11. Fixed Mask Key Requirements • Define clear aperture for diagnostics as a 5 x 10 cm image at NEH (757.404 m) • Protect downstream equipment from non-central radiation • Align aperture within 1 mm of beam position

  12. Fixed Mask Concept Tantalum Mask – 5 cm thick 6 Strut System 0.03mm Resolution 5 DOF Mount

  13. X-ray Slit Key Requirements • Defines precision aperture of x-ray laser • Able to choose any rectangular area inside clear aperture of fixed mask – 0.16 mm or larger • 10 micron linear resolution • Blocks aligns to beam axis within 29.5 arc-seconds • Compatible with high vacuum environment • Opens to clear aperture for diagnostics • Compatible with EPICS control system

  14. X-ray Slit General Specifications • Two pairs of slits • One horizontal • One vertical • Stages compatible with 1E-6 Torr • Slits open beyond clear aperture • 6 strut system can yield 0.03 mm resolution

  15. X-ray Slit Movement Specifications • Radial motion • 360 degree travel • 3 arc-sec resolution • 30 arc-sec accuracy • 6 arc-sec repeatability Horizontal Slit Block - B4C • Linear motion • 100 mm travel • 1.25 m resolution • 2 m accuracy • 2 m repeatability Limit Switch (2) Manual Rotary Stage Limit Switch Adjuster (2) Motorized Linear Stage Motorized Rotary Stage

  16. Solid Attenuator Concept • 256 attenuation levels • Eight beryllium slides • Each twice as thick as the last (0.3 to 38.4 mm) • Up to 99.998% attenuation of 8.26 keV x-rays • Millions of attenuation levels when used with gas attenuator • Pneumatically actuated

  17. Sample of Predicted Transmission Levels

  18. XTOD Vacuum System Requirements Average Pressure < 10 -5 Torr Long Pump life time > 10 yrs Specified life time for most ion pumps @ 10 -6 Torr > 50,000 hrs (~6 yrs) Specified life time for VacIon Starcell @ 10 -6 Torr > 80,000 hrs (~9 yrs) Design Tube Vacuum Level 3x10-6 Torr Max Operating Level 6x10-6 Torr Ion Pumps Operated below 10 -6 Torr

  19. 38 Flange Joints 57.8’ 116.3’ 57.8’ 57.8’ 116.3’ 57.8’ 57.8’ 116.3’ 57.3’ 58.15’ 58.15’ 58.15’ 231.9’ 231.9’ 231.9’ 24.85’ 718.5’ VACUUM VALVE ION PUMP TURBO PUMP Sketch of 212-m tunnelwith pump locations 4” OD tube is in 10ft sections with metal gaskets. At each pump, there are 7” bellows, 4” dia. cross, and gate valve – all joined with metal gaskets.

  20. Leak Check Valve Cold Cathode Gauge, MKS 422 Bellows Beam Tube, 4.00” OD X .083” W 6” Conflat Flange 4-Way Cross Valve, VAT Series 48 DN 100 (4” ID, 6” Conflat) Support Varian V70LP Turbo Pump Varian TriScroll 300 Pump Turbo Pump and Support Flex Support

  21. Rupture Disk Cold Cathode Gauge, MKS 422 Bellows Beam Tube, 4.00” OD X .083” W 6” Conflat Flange 4-Way Cross Varian StarCell 75 Ion Pump Flex Support Support Ion Pump and Support

  22. Lumped parameter analysis S(L/sec)=Q (Torr-L/sec) / P(Torr) • Total volume = 1603 L • Total area = 6.6x105 cm2 outgassing at 1x10-10 Torr-L/sec/cm2 after 100 hrs • 110 - 4” gaskets each leak at 6x10-7 Torr-L/sec • Then Q=1.3x10-4 Torr-L/sec, total gas load at 100 hrs (50% is from 110 seals) • So for a design pressure of 3x10-6 Torr then with no conductance loss, S = 44 L/sec • But for a 106-m tube, C = 1 L/sec so we need multiple pumps

  23. Pressure history is calculated at eachsubvolume N for 100 hours • Model solves the gas load matrix with N coupled differential equations 4 times • Roughing from 760 to 0.01 Torr for 5 hrs • Turbo pumping to below 10-5 Torr for 30 hours • Ion pumping in the -6 range to 100 hours • Failure of ion pumps for few minutes • Gas Load Balance: Vndpn/dt =  Qn in –  Qn out for n =1,N • Where Qn in = leakage and time-dependent outgassing into n Qn out = Cnm (Pn -Pm) where m is an adjacent volume Or Qn out = (S Cnp / (S + Cnp) Pn • where Cnp is the conductance between n and the pump • and S (Pn) is the pressure dependent pump speed. • Methodology verified in experiment • Pressure gauges on APT at LANL verified the predictions by the Mathematica model that was programmed to fit that geometry

  24. . 100 1000 10000 100000 Model provides 100 hr historyof pressure at any location 100 Scroll Pressure, Torr 1 10-2 Turbo 10-4 Ion 10-6 10-8 Time, sec 1 31 100 hrs

  25. 1.2 1.0 Pressure, 10-6 Torr 0.8 0.6 0.4 Z , meters 50 100 150 200 Pressure profile with 6-75 L/s ion pumps at 100 hrs For SnomimalTotal = 450 L/s, SnetTotal = 327 L/s Theory: P=Q/S = 4.1 x10-7 Torr. The best that can be achieved. Code: Pavg = 8.4 x10-7 Torr. So our design is efficient!

  26. Nsv 50 100 150 200 Nsv 50 100 150 200 Permanent turbo pumps can replace failed ion pumps to keep P < 6 x 10-6 Torr 10-6 Torr Two failed adjacentIPs Pmax = 7.2 x 10-6 Torr (above specs) Pmin = 3.7 x 10-7 Torr 6 4 Pmax = 2.2 x 10-6 Torr (within specs) Pmin = 3.2 x 10-7 Torr 2 0 Two failed adjacentIPs with middle turbo on 10-6 Torr 10-6 Torr 2 5 3 1 2 2 min 1 seconds 0 0 400 800

  27. Turbo pumps reduce pressure belowdesign even when 4 ion pumps fail 2nd,3rd 4th,5th failed 3rd,4th,5th failed 3rd,4th failed 2nd,4th,5th failed 1, 2, or 3 turbos on 2nd,4th failed 4th failed Design pressure during IP failure All working

  28. To optimize the system, number and pump size wasvaried to keep 450 L/s total nomimal pumping Six 75 L/s ion pumps meets the reqs with margin and reasonable costs 8 Max limit 6 Maximum pressure 10-6 Torr 4 Single failure, no backup Design limit 2 Normal 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 Number of Ion Pumps

  29. The XTOD Work Plan Will Complete the Tunnel and Experimental Hall Mechanical & Vacuum Systems and the 1st Half of FEE Systems in FY06 • FYO6 Efforts • Design mechanical and vacuum systems through tunnel • Design FEE up to Diagnostic Package (Fast Valve, Fixed Mask, Slit, Solid & Gas Attenuators, Ion Chambers) • Complete conceptual designs for FEL Offset, TEM, Spectrometer, Imagers • Design XTOD Controls systems (details up to FEE Diagnostic Package and the Tunnel) • Prototype Efforts for Gas Attenuator, Tunnel Vacuum System, and Total Energy Monitor (TEM) • Complete Damage Study • Continue simulation efforts of physics models and to support engineering specifications • Prepare procurement package for all final design systems • FY07,FY08 Efforts • Final Design for FEE- Diagnostic Package and FEL Offset System (Nov 07) • Complete XTOD Controls • Procure, Build, Test, and ship all systems to SLAC • (Beneficial Occupancy Dates: FEE-Oct. ’07, NEH-June ’07, Tunnel- Oct ’07, Sept ‘07) • Refine simulation models and support commissioning activities • XTOD Commissioning

  30. Several Key XTOD Technical Documents/Specifications Have Been Completed • “LCLS Spontaneous Radiation with Reflection along the Beam Line in the Undulator Pipes “, Kirby Fong • “The LCLS Gas Attenuator”, D.D. Ryutov • “Photoluminescence as a way of non-destructive imaging at the LCLS facility”, D.D. Ryutov • “Indirect Imager Requirements”, M. Pivovaroff • “SiC Mirror Specifications”, M. Pivovaroff • “Commissioning Diagnostics Specifications”, R. Bionta

  31. Summary • FEE layout has stabilized including FEL Offset System • TTF Damage experiment has been conducted (SiC, B4C ) • Significant progress on upstream FEE systems and Tunnel • Prototype efforts on the Total Energy Monitor are yielding promising results • Prototype efforts for Gas Attenuator to begin in November • Controls efforts are keeping pace developing entire XTOD system layouts, alignment of XTOD controls with LCLS standards, and installation of EPICS at LLNL

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