1 BROOKHAVEN SCIENCE ASSOCIATES 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

2 BROOKHAVEN SCIENCE ASSOCIATES 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 BROOKHAVEN SCIENCE ASSOCIATES Outline 1.Scientific Mission 2.Beamline Overview Beamline Requirements and Specifications Optics and beamline layout (major changes since last EFAC meeting) 3.EFAC comments 4.1 st BAT meeting comments action items 5.Other design issues 6.Cost and Schedule 7.Conclusions

4 BROOKHAVEN SCIENCE ASSOCIATES 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 BROOKHAVEN SCIENCE ASSOCIATES 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 μ m horiz. x ~5 μ m vert. (2-  ) >95% overlap of the two polarized beams on sample Flux: ~2 x 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 1:10 3 stability) –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) 2.1. High coherent flux and full polarization control branches High coherent branch –Stable intensity (desire 1:10 4 stability) –Stable beam (desire <10% of the pinhole size)

6 BROOKHAVEN SCIENCE ASSOCIATES 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 2.2. Soft Coherent X-ray Beamline since last EFAC review Full polarization control branch 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 SGM mono High coherent flux branch

7 BROOKHAVEN SCIENCE ASSOCIATES CSX beamline real-space layout Full polarization control branch High coherent flux branch

8 BROOKHAVEN SCIENCE ASSOCIATES CSX beamline real-space layout Full polarization control branch High coherent flux branch

9 BROOKHAVEN SCIENCE ASSOCIATES 3. Response to Comments from EFAC CommentResponse Combining both programs into a single beamline has compromised the capabilities of both branches to some degree Calculations show both branches performance should be best in their own class Canting the ID’s and its use as single device. The phasing of the two undulators will be important and further studies are needed. On going studies regarding the canting and the phasing of the ID’s. Problem related with straight section length, front end, and floor space Specific comments on beamline design details: need of multiple mirrors requires careful planning and design, the power load on the mirrors should be check, soft x-ray range allows for much tolerance for the slope errors than a hard x- ray mirrors Various step process, design and FEA (in first mirrors) will go hand by hand. Mirrors and gratings tolerances are being checked. Collaboration with metrology R&D Care has to be taken during the design phase to make sure that the coherence is preserved at the sample with the maximum flux Both branches optical design will request to have wave front analysis

10 BROOKHAVEN SCIENCE ASSOCIATES 4. 1 st 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 BROOKHAVEN SCIENCE ASSOCIATES 4. BAT recommendations: action items (29) ItemsStatus Beamline ID’s Energy range > 270 eV (linear vert.) Need/required QEPU to eliminate higher harmonics EPU49 is current choice, under study the beamline performance with this selection. R&D for QEPU Beamline operation schemes Fast switching, dual or single operation Operation schemes are limited by length of the straight as well as the insertion of an “ID phaser” Pending final decision for fast switching scheme. Need to contact BESSY and ESRF to investigate “phaser” Beamline optics : a) high coherent flux, b) full polarization control Recommendation to assign R & D for gratings* and optics** First optics need to repeat FEA analysis and specially a) wave front analysis for coherence preservation Concern Zeiss stop grating fabrication, searching for collaborations to obtain state of the art gratings Ruben Reininger is keeping in contact with group in Germany willing to start a company. Many items are related with each other: Switching scheme, real state at straight section, ID’s performance (period) relates with optics performance, requires of FEA analysis and new cost estimates.

12 BROOKHAVEN SCIENCE ASSOCIATES 4. BAT recommendations: action items (29) List of other ItemsStatus Analysis for ZP positioning in coherence branchSame analysis as for nanofocus hard x-ray beamline Vibration analysis for optics and end-stationsNeed evaluation Detector requirements for beamline/endstationsPreliminary list includes area detectors (fast read out) and photon counting detectors, list keeps growing Error analysis in full polar. branch with 6 degrees of freedom in first optics, specially energy shifts Request has to go to Ruben Reininger BPM’s and diagnostics specific for soft x-raysIn contact with Diamond ID6 and BLADE beamlines and PETRA-III soft x-ray beamline

13 BROOKHAVEN SCIENCE ASSOCIATES 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 Magnet Parameters: Br = 1.25 (NdFeB) Transverse Dimensions: 38 mm x 38 mm or 30 mm x 30 mm Horizontal Gap: 1 mm 270 eV 49 mm period Oleg Chubar & Toshi Tanabe BAT conditions for the selection of the EPU period: Min hv vert 270 eV High energy… Period length 47mm 48mm49mm 51mm Min hv lin horiz 180 eV170 eV 160 eV 140 eV Min hv circ 260 eV eV 180 eV Min hv lin vert 310 eV 280 eV 260 eV 220 eV Min hv lin 45deg 440 eV 400 eV380 eV 320 eV Max hv (K=0.2) 1780 eV1740 eV1710 eV1630 eV

14 BROOKHAVEN SCIENCE ASSOCIATES 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 Magnet Parameters: Br = 1.25 (NdFeB) Transverse Dimensions: 38 mm x 38 mm or 30 mm x 30 mm Horizontal Gap: 1 mm 49 mm period 1700 eV Oleg Chubar & Toshi Tanabe figure with comparison brightness for different EPU periods BAT needs EPU45 performance

15 BROOKHAVEN SCIENCE ASSOCIATES 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 BROOKHAVEN SCIENCE ASSOCIATES CSX source usage modes (con’d) Source Usage ModeUndulatorsCoherent branchPolarization Control Branch Not sharedIn line (phased)M0 mirror inserted Not sharedIn line (phased) or canted M0 mirror retracted; use dedicated optics for either (a) in-line (phased) undulators as a single source or (b) canted undulators with different polarizations selected by chopper SharedCanted: upstream undulator pointing inboard, downstream undulator pointing outboard M0 mirror inserted in upstream undulator beam; use upstream undulator beam Use downstream undulator beam

17 BROOKHAVEN SCIENCE ASSOCIATES Real estate problem in the low-  straight 2 x EPUs (APPLE II) canted by 0.16 mrad (horizontal plane) Number of periods 44 Period length45 mm K max 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 BROOKHAVEN SCIENCE ASSOCIATES CSX front end layout SGV - slow gate valve FAPM - fixed aperture mask XBPM - photon BPM (non-absorbing) x two beams CO - lead collimator PS - photon shutter M0 – mirror * move to the beamline front end SS - safety shutter ** m m 18.85m m m m m m m Non-standard items needed: adjustable white beam apertures Items not needed: No need for differential pumping section (windowless, ultra-high vacuum beamline) m

19 BROOKHAVEN SCIENCE ASSOCIATES Side View CSX beamline optics layout optics specifications vs metrology Horizontal Focusing by M4 -- ~52:1 Fast Switching: change M1 and M3 Beamline High flux fast switching branch High flux coherent branch Source to M m m M1 to entrance slit m M1 to M2 ~ 2.43 m M1 to grating ~ 2.50 m m Grating to exit slit ~10.00 m ~ 2.09 m Exit slit to M3 ~ 1.20 m M3 to M m M4 to sample 1.00 m Total ~45.00 m Plane M2 Plane grating VLS Exit Slit Cylindrical M1 Sample Plane Ellipticals M3, M4 Planar M0 Top view Toroidal M1 Spherical grating Sample Entrance slit Exit pinhole inside chamber Side view 100 nrad RMS planes 500 nrad RMS Elliptical, cylinder meridional In_Sync currently (April 16 th 2009) Plane 200 nrad RMS Sagital cylinder 500 nrad RMS

20 BROOKHAVEN SCIENCE ASSOCIATES Energy resolution vs Slope errors

21 BROOKHAVEN SCIENCE ASSOCIATES Coherent branch endstation 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 Currently final assembly soon moved to X1A Status

22 BROOKHAVEN SCIENCE ASSOCIATES Polarization control endstation 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 Status

23 BROOKHAVEN SCIENCE ASSOCIATES 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. Undulator Beamline 4: Coherent Soft X-ray Scattering (CXS) Total Estimated Cost ($ x 1000) WBS Description Direct $ Total Burdened & Escalated Bottoms up Contingency Total with Contingency FTEsLabor Non-Labor (Mtrl, Trvl, Act) %$ Value Undulator Beamline 4 Coherent Soft X-ray Scattering (CXS) 22.61,7996,79211,709445,16016, First Optic Enclosure Layout & Transport Utilities White Beam Apertures First Mirrors (M0 & M1) , , Monochromator (M2 + gratings) ,0681, , Exit Slits , , Polarization Selection Components Branching Mirror Refocusing Mirror ,0142,70361,4604, Personnel Safety System Equipment Protection System Endstation ,1101, , Beamline Controls Beamline Control Station Beamline Management , ,015 Material and labor costs estimated*** for high coherent flux branch ~ $ 543 kM0 Mirror * ~ $ 673 kWater-cooled entrance & exit slits * ~ $ 650 k Grating chamber ~ $ 360 k Labor (120k x 3) ** ~ $ 2,226 kTotal for coherent branch Material and labor costs recovered by removal of one branch ~ $ 361 kBranching mirror * ~ $ 338 kWater-cooled exit slit * ~ $ 999 k M3 and M4 refocusing mirrors * ~ $ 350 kLabor (115k + 115k + 120k) ** ~ $ 2,048 kTotal recovered costs * Includes diagnostics, transport, and vacuum hardware ** includes labor for specification, procurement, QA testing, and installation *** rough estimates, need to be refined

24 BROOKHAVEN SCIENCE ASSOCIATES Beamline Budget With the final design BAT recommends new cost estimates

25 BROOKHAVEN SCIENCE ASSOCIATES 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 BROOKHAVEN SCIENCE ASSOCIATES 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 (~10 14 ph/s), with resolving power of the order of uses both insertion devices in phase as one, with a reduced number of optics Polarization control branch: high photon flux (2 x ph/s) with ~ 10 4 power resolution -uses both insertion devices with “opposite” polarizations, -Fast switches between polarizations