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High Coherent Flux and Full Polarization Control NSLS-II CSX Project Beamline

High Coherent Flux and Full Polarization Control NSLS-II CSX Project Beamline. Cecilia S á nchez-Hanke with acknowledgements to the CSX BAT and NSLS-II XFD team NSLS-II EFAC Review April 23, 2009. High coherent flux and full polarization control BAT.

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High Coherent Flux and Full Polarization Control NSLS-II CSX Project Beamline

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  1. High Coherent Flux and Full Polarization ControlNSLS-II CSX Project Beamline Cecilia Sánchez-Hanke with acknowledgements to the CSX BAT and NSLS-II XFD team NSLS-II EFAC Review April 23, 2009

  2. High coherent flux and full polarization control BAT H. Ade, D. A. Arena, S.L. Hulbert, Y. Idzerda, S. Kevan, C. Sánchez-Hanke and S. Wilkins CSX Beamline Advisory Team *Rubén Reininger, Scientific Answers & Solutions, Madison, WI

  3. Outline Scientific Mission Beamline Overview Beamline Requirements and Specifications Optics and beamline layout (major changes since last EFAC meeting) EFAC comments 1st BAT meeting comments action items Other design issues Cost and Schedule Conclusions

  4. 1. Scientific Mission Complementary scientific programs on two branches: Full Polarization Control and High Coherent Flux Surfaces / Buried Interfaces in SCS Imaging Complexity/inhomogeities Diffraction Microscopy Coherent Imaging Soft Matter Magnetic Interfaces Dynamics

  5. 2.1. High coherent flux and full polarization control branches Specifications ~ 200 to 2000 eV energy range high coherent flux (maximize) circular and linear polarization with fast-switching capability up to kHz spot size on sample: ~4 μm horiz. x ~5 μm vert. (2-) >95% overlap of the two polarized beams on sample Flux: ~2 x 1013 photons/sec/0.1%bw Requirements A high degree of stability, of both the electron beam and the beamline optics, to provide: Full polarization control branch Stable intensity and polarization (desire 1:103stability) Stable beam position (desire <10% of focused beam spot size at the sample) Stable beam overlap in fast-switching mode (desire <5% of focused beam spot size at the sample, which equates to <2.5% beam position wander, as a fraction of the focused beam spot size) • High coherent branch • Stable intensity (desire 1:104stability) • Stable beam (desire <10% of the pinhole size)

  6. 2.2. Soft Coherent X-ray Beamline since last EFAC review High coherent flux branch Full polarization control branch SGM mono Changes: SGM branchline specifically for coherent studies – minimum number of reflections. Full polarization control branch with flexible control of flux (polarization & switching). Move branching mirror into FE – now also provides focusing Changes: SGM branchline specifically for coherent studies – minimum number of reflections. Full polarization control branch with flexible control of flux (polarization & switching). Move branching mirror into FE – now also provides focusing Changes: SGM branchline specifically for coherent studies – minimum number of reflections. Full polarization control branch with flexible control of flux (polarization & switching). Move branching mirror into FE – now also provides focusing

  7. CSX beamline real-space layout High coherent flux branch Full polarization control branch

  8. CSX beamline real-space layout Full polarization control branch High coherent flux branch

  9. 3. Response to Comments from EFAC

  10. 4. 1st BAT meeting in January 2009 Goals: a) provide guidance to finalize the optical design b) provide guidance for beamline operation schemes c) provide guidance for endstations Agenda talks: a) Ruben Reininger “Beamline optics and layout” Toshi Tanabe “CSX beamline ID’s” Steve Hulbert “Undulator-overlaping issues” b) Paul Steadman c) Konstantine Kaznatcheev

  11. 4. BAT recommendations: action items (29)

  12. 4. BAT recommendations: action items (29)

  13. APPLE-II “Period Choice Chart” Minimal (for 11.5 mm Gap) and Maximal Photon Energies of the Fundamental Harmonic vs Undulator Period for 3 GeV Electron Energy BAT conditions for the selection of the EPU period: Min hv vert 270 eV High energy… Oleg Chubar & Toshi Tanabe 49 mm period 270 eV Magnet Parameters: Br = 1.25 (NdFeB) Transverse Dimensions: 38 mm x 38 mm or 30 mm x 30 mm Horizontal Gap: 1 mm

  14. APPLE-II “Period Choice Chart” Minimal (for 11.5 mm Gap) and Maximal Photon Energies of the Fundamental Harmonic vs Undulator Period for 3 GeV Electron Energy Oleg Chubar & Toshi Tanabe figure with comparison brightness for different EPU periods 49 mm period 1700 eV BAT needs EPU45 performance Magnet Parameters: Br = 1.25 (NdFeB) Transverse Dimensions: 38 mm x 38 mm or 30 mm x 30 mm Horizontal Gap: 1 mm

  15. CSX full polarization control branch:switching using static canted EPUs Single beam mode: x2 flux • Fixed polarization selection • Linear (sigma OR pi) • Circular (left OR right) Static canted beam mode, fast switchable using chopper • Fast-switching polarization selection • Linear (sigma AND pi) • Circular (left AND right) 0.16 mrad

  16. CSX source usage modes (con’d)

  17. Real estate problem in the low-b straight 2 x EPUs (APPLE II) canted by 0.16 mrad (horizontal plane) Number of periods 44 Period length 45 mm Kmax 4.33 (linear mode), 2.69 (circular mode) Low-straight section (6.7 m long, as of May 2008) Need space for 2 insertion devices plus 3-5 canting magnets Need space for BPMs Length: 2m August 2007 J. Skaritka courtesy

  18. CSX front end layout Non-standard items needed: adjustable white beam apertures Items not needed: No need for differential pumping section (windowless, ultra-high vacuum beamline) 17.85 m 18.25 m 18.85m 19.35 m 19.65 m 20.15 m 24.15 m 24.85 m 27.05 m • SGV - slow gate valve FAPM - fixed aperture mask XBPM - photon BPM (non-absorbing) x two beamsCO - lead collimator PS - photon shutter • M0 – mirror* move to the beamline front end • SS - safety shutter ** 20.50 m

  19. CSX beamline optics layout optics specifications vs metrology Sample Sample Top view Entrance slit Exit pinhole inside chamber Toroidal M1 Spherical grating Cylindrical M1 Plane M2 Planar M0 Plane Ellipticals Exit Plane grating Side view Slit M3, M4 Side View VLS • Fast Switching: change M1 and M3 • Horizontal Focusing by M4 -- ~52:1 • 100 nrad RMS planes • 500 nrad RMS Elliptical, cylinder meridional In_Sync currently (April 16th 2009) Plane 200 nrad RMS Sagital cylinder 500 nrad RMS

  20. Energy resolution vs Slope errors

  21. Coherent branch endstation Status Currently final assembly soon moved to X1A • Technique • Soft X-ray Diffraction Microscopy • Coherent scattering imaging retrieval Experimental capabilities • In-vacuum diffraction chamber • 30 nm zone plate • Polarization analysis • Temperature control down to • 5 K

  22. Polarization control endstation Status • Experimental capabilities • In vacuum diffractometer • Magnet 1 Tesla (in x, y and z) • Sample transfer • Sample temperature down to ~20 K • Future • Motorized multiple pinholes • Polarization analyzer Under construction; Chamber is in hause as many of the other parts will serve NSLS X13A user community prior to NSLS-II starts operations

  23. Undulator Beamline 4: Coherent Soft X-ray Scattering (CXS)Total Estimated Cost ($ x 1000) Material and labor costs recovered by removal of one branch ~ $ 361 k Branching mirror * ~ $ 338 k Water-cooled exit slit * ~ $ 999 k M3 and M4 refocusing mirrors * ~ $ 350 k Labor (115k + 115k + 120k) ** --------------------------------------------------------------- ~ $ 2,048 k Total recovered costs Material and labor costs estimated*** for high coherent flux branch ~ $ 543 k M0 Mirror * ~ $ 673 k Water-cooled entrance & exit slits * ~ $ 650 k Grating chamber ~ $ 360 k Labor (120k x 3) ** ---------------------------------------------------------------------- ~ $ 2,226 k Total for coherent branch * Includes diagnostics, transport, and vacuum hardware ** includes labor for specification, procurement, QA testing, and installation *** rough estimates, need to be refined WBS Dictionary:All activity related to the design, construction, and commissioning (without beam) of an insertion device soft x-ray beamline covering an energy range between 200 to 2000 eV, with the capability to perform experiments using the coherent part of the photon beam, and switchable polarization.

  24. Beamline Budget With the final design BAT recommends new cost estimates

  25. CSX Beamline: Status and Plans • Polarization control branch of beamline design in good shape (Ruben Reininger) • End station(s) to be transferred from NSLS (currently in design/manufacture) • Coherent branch conceptual design needs to be finalize (Ruben Reininger, Sept. 2009) • Thermal FEA analysis required for first mirrors of both branches • Review of fast switching options: • baseline optical design is based on static canted sources • analysis of relative accelerator (real estate) and beamline risks, costs, and benefits of each scheme scheme

  26. Summary Design of a unique best-in-class high performance dual branch soft x-ray beamline with flexibility to perform world class science in the soft x-ray energy range (270 to 1700eV) Coherent branch: high coherent photon flux (~1014 ph/s), with resolving power of the order of 1000 uses both insertion devices in phase as one, with a reduced number of optics Polarization control branch: high photon flux (2 x 1013 ph/s) with ~ 104 power resolution uses both insertion devices with “opposite” polarizations, Fast switches between polarizations

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