Workshop Overview & Charge, Science Examples, Instrumentation R&D. Bill Schlotter Feb. 9, 2015

Transcription

1 Workshop Overview & Charge, Science Examples, Instrumentation R&D Bill Schlotter Feb. 9, 2015

2 Outline Workshop Charge Workshop Format Breakout activities Scientific Opportunity Example From workshops to transformational science at LCLS-II Planning for Instruments at LCLS-II

3 Our Charge

4 Ensuring LCLS-II will be useful for our science The strength of the Scientific Opportunities we develop and refine over the next two days will guide the capabilities developed for LCLS-II X-ray Parameters Instrumentation Methods Our workshop will form the basis for a document describing the most important Scientific Opportunities at LCLS-II. Our workshop will inform the instrumentation developed for LCLS-II

5 Workshop Charge (Identifying Science) To identify the most important science opportunities (transformational, grand challenge level) that can uniquely be addressed using capabilities of LCLS-II (high rep rate <5 kev, 1-25 kev at 120 Hz) Near-term science consistent with LCLS-II baseline Future science consistent with potential LCLS-II upgrades Succinct statement of why this science is transformational What are important outstanding questions in your field? Why have they not been answered (what is impeding progress, why now, why LCLS-II)? What is the potential broader impact if we can answer these questions (why are they important)? Plenary speakers will outline selected important science areas setting the stage for the breakout discussions.

6 Workshop Charge (Experiments, Parameters, Alternatives?) Map out experimental approach and key requirements for: Beamline optics, endstation(s), detectors, lasers, sample injectors etc. Identify key capabilities, consistent with nominal LCLS-II baseline (and upgrades secondary) Photon flux, pulse duration, rep rate, tuning, polarization, etc. Compare experimental approach to current state-of-the art & assess alternative approaches Can the experimental approach leverage existing instrumentation/expertise? What R&D is required? Can the science be done with other existing sources? (e.g. diffraction-limited synchrotrons, table-top HHG, etc.) Breakout sessions will identify priority science opportunities linked to LCLS-II & outline experimental approaches and parameters

7 Workshop Format

8 Material Physics Workshop Format Day 1 (Monday) Morning: Introduction Plenary Speakers Afternoon: Lunch Plenary Speakers Breakout Sessions Dinner Homework Day 2 (Tuesday) Morning: Plenary Speakers Breakout Sessions Afternoon: Lunch Breakout Sessions Breakout Closeout Depart Breakouts: All are encouraged to present ideas template provided Each breakout will deliver a summary at the closeout session Scribes will take notes and collect presented materials for internal use only.

9 Breakout List Topics Magnetism & spin dynamics Correlated materials & charge-collective modes Materials physics nanoscale structure, domains, grain boundaries Co-Leaders Hermann Durr, Peter Fischer Z.X. Shen, Tom Devereaux, Zahid Hussain Aymeric Robert, David Reis, Steve Kevan Each breakout will be introduced in more detail this afternoon

10 Breakout Contribution Template Everyone is encouraged to contribute a scientific opportunity for LCLS-II Template slides provide a guide for input. It s not to late to start!

11 Breakout Deliverables Summary slides for closeout that address the charge Written notes addressing the charge with respect to scientific impact and relevance to LCLS-II Answers to the LCLS-II parameters questions Notes from breakout discussion (scribe) Collection of slides (on a memory stick) presented at the breakout. (scribe)

12 Breakout discussion FAQ Q: LCLS-II sounds great, but it can t answer the most important questions in my field...should I go home? A: You should stay. Focus on the key pieces where LCLS-II can provide unique insight. Q: I have this great idea, but it requires 10fs synchronization between the optical and x-ray pulses, and the spec is <20fs. A: Requirements outside of the nominal should provide a clearly justified scientific opportunity. Develop meaningful scientific advances starting with <20 fs (nominal) synchronization and working toward the target synchronization. Q: I can do my experiment at LCLS today. At LCLS-II, I would do the same thing just a 1000 time faster. Is that really unique? A: It depends, but if you need one year of LCLS-I beamtime which you obviously can t get to make progress on your experiment and one shift at LCLS-II would do the same then YES that is unique.

13 Build from previous work! SLAC/LBNL 2008 BES Document are available on the workshop website

14 Scientific Opportunity An Example

15 Understanding Multi-electron Photo-Catalytic Systems Science Challenge/Opportunity Understanding natural and artificial photo-catalysts on natural time scales and under operating conditions Critically missing is a complete characterization of the electronic and atomic structure of rare/transient intermediate states responsible for key steps in catalysis (e.g. water splitting) Significance & Impact Deeper understanding of natural photo-catalysts is essential to design efficient, robust, chemically selective catalytic systems from earth-abundant elements Optimization of artificial systems requires characterization of their dynamics under operating conditions Challenges & LCLS-II Strengths Important grand challenge level scientific question LCLS-II connection Sub-nm resolution, chemical specificity, dynamics. Tunable ultrafast soft X-rays at high rep rate will enable chemically-specific characterization of rare transient intermediate states (occupied, unoccupied and collective states) via time-resolved RIXS. Two-color, tailored laser excitation, wet RIXS endstation S 4 H +, e - S 0 S hn 1 O 2 e - H +, e - hn S 3 hn hn H +, e - S 2 O 2 Evolving Catalyst Mn 4 CaO 5 4-photon, 4-electron catalyst with dynamics spanning sub-psec to msec. Critical S 4 state is metastable and has eluded characterization with present methods/sources. Baseline and future upgrade Your Name Workshop (Chemistry, Materials, life Sciences) Breakout Session

16 energy loss (ev) Experimental Approach Techniques(s) Dynamic electronic structure of transition-metal catalysts. Chemical specificity to transition-metal and ligand(s) Time-resolved RIXS, two-color spectroscopy, stimulated Raman, multidimensional spectroscopy Tools High-resolution (100 mev), high-throughput RIXS spectrometer for solution-phase samples (jets or droplets for shot-to-shot sample replacement. Suitable designs are presently available that represent a modest advance beyond current instruments. Two-color and multidimensional spectroscopy requires independently tunable pulses from FEL (DE ~0-500 ev), and optics for manipulating them. Alternatives Synchrotron approaches rely on largely static measurements of crytrapped states. Not all intermediates can be cryo-trapped, and fixed samples are susceptible to damage as significant accumulated photons are required. Your Name Take Credit! Time resolved RIXS, twocolor spectroscopy. Alternatives discussion 1 MLCT 3 MLCT N-1s DE hν out Resonant Inelastic X-ray Scattering (RIXS, X-ray Raman) Occupied & unoccupied states Charge transfer Multi-particle excitations Specific and quantitative parameter requirements incident energy (ev) static N K-edge RIXS map - S o (BESSY Wernet, Huse et al.)

17 From this workshop Through instrumentation To important science at LCLS-II

18 Toward Science at LCLS-II Delivering effective capabilities for science requires parallel effort Science Scientific opportunities are identified through the workshop, and through ongoing activities of science working groups, and captured in a science document R&D R&D and planning for LCLS-II instrumentation is ongoing at the LCLS facility, and will be guided and prioritized in large part by science opportunities and needs identified for LCLS-II LCLS-II LCLS-II beam parameters are optimized by the LCLS-II project with guidance from scientific drivers.

19 Input for R&D The LCLS operating facility will guide instrumentation for LCLS-II. R&D is underway in many areas X-ray Detectors Pump Lasers Data Acquisition Sample Delivery LCLS-II accelerator parameters being developed and priorities Bi-weekly discussion between with LCLS & LCLS- II to inform and drive progress in these areas. Polarization Control Seeding

20 LCLS-II & Instrumentation

21 LCLS-II Operating Facility Layout NEH FEH Cu Linac H3 H4 H4.5 H5 H6 NEH FEH SC Linac H1 H2 4 GeV, 0.3 ma, 1.2MW H kev (120kW) H4 H4.5 H5 H6 Polarization currently under evaluation Soft x-ray undulator is linear horizontal. Option for elliptical polarization control requires strong scientific support Hard x-ray undulator has option for either linear vertical or linear horizontal.

22 Soft x-ray instrumentation at LCLS-II As part of the LCLS-II project, a single soft x-ray beamline (200eV-1250eV) will be built. The current soft x-ray beamlines in hutches 1 and 2 will be removed. Scientific opportunities will drive additional instrumentation Monochromatic beamline High resolution x-ray emission spectrometers Reaction-microscope system Pulsed magnetic field systems Upgraded or new end station systems

23 Instrumentation plan for LCLS-II Space for instruments at LCLS-II is constrained by the layout of the Near and Far Experiment Halls. Significant reconfiguration and development of the NEH instruments is expected. Control Rooms Future Instrument Space Future Instrument Space

24 Hard x-ray instrumentation The hard x-ray instruments will remain in the same location for LCLS-II with ancillary upgrades necessary for LCLS-II compatibility All four hard x-ray instruments can use the LCLS-II beam XPP, XCS and MEC can operate at photon energies as high as 25keV at lower repetition rates because a mirror upgrade project that is currently underway. Because of a mirror upgrade the CXI instrument will be capable of delivering focused beam at higher repetition rate. Future detector, pump laser and DAQ upgrade options are part of the current LCLS facility development.

25 Summary We are charged to develop important science opportunities unique to LCLS-II at the startup of LCLS-II and beyond. Breakout group deliverables will develop into the Scientific Opportunities Document The R&D on instrumentation at LCLS along with the development of the LCLS-II project are underway in parallel now is the time to begin refining the instrumentation plan.

26 Questions & Discussion

27 END