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Persis S. Drell Stanford Helmut Dosch DESY Persis S. Drell Helmut Dosch Stanford DESY Outline • Introduction • BESAC Contributions & Impact – John Hemminger’s Leadership – Most recent recommendations on future BES light source facilities • Americas Perspective – Science Results & Drivers – New Rings & FELs • Asia & Europe Perspective – Science Results & Drivers – New Rings & FELs • Concluding Remarks 2 BESAC Contributions & Impact to BES Facilities • Dr. John Hemminger: 13 years as BESAC Chairperson – Key BESAC & SC Strategic Planning Reports (See Below) – New Facilities: SNS, 5 NSRCs, LCLS, NSLS-II, LCLS-II, APS-U, … 20000 Near Doubling of BES User Community 8.8K → 16.3K since 2004! 15000 10000 5000 0 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 NSLS II NSLS SSRL ALS APS LCLS HFBR IPNS SNS HFIR LS Users: 7.7K → 11K Lujan EMC NCEM ShaRE CNMS MF CINT CNM CFN Basic Energy Sciences Report of the BESAC Report Facilities Prioritization BESAC Subcommittee on on Future X-ray Light Facility Upgrades Co-Chaired by : Sources John C. Hemminger, Chair Univ ersity of California, Irv ine & William Barletta Approv ed by the Approv ed by the Basic Energy MIT Basic Energy Sciences Sciences Adv isory Committee Adv isory Committee on February 26-27, 2013 on July 25, 2013 June 9, 2016 3 Motivation: Desire to Probe Nature at Atomic Length (Å) & Time (fs) Scales Seeing the Invisible in Real Materials Where are the Atoms? Compositional Newly discovered heterogeneity in a structure of a LiNi1/3Co1/3Mn1/3O2 hydrogen-stuffed, battery hundreds quartz-like form of of hours after ice charging Less 3 µm More Charged Charged Adv. Materials (2016) JACS (2016) Where are the Electrons & Spins? What are the Dynamics? Capturing the transient behavior Direct measurements of catalytic bond formation of "pure" ac spin Science (2015) t < 0 300fs 500fs 800fs >1 ps currents (flow of spin angular momentum without flow of charge) PRL (2016) Goal: Control Matter & Energy on These Scales! 4 Light Sources Are Alive & Kicking: 60+ Facilities Worldwide & Growing Many other new & upgraded facilities are in the design stage… Take Away Message: It’s a very competitive landscape! ALS SACLA FEL 2011 FLASH I & II 8.5 GeV, 30 Hz NC APS Japan: Spring-8-II PAL XFEL 2016 NSLS-II 10 GeV, 60 Hz NC China: BLS Ring Only Ring & FEL SWISS FEL 2017 SSRL Germany: PETRA 3/4 FEL Only 5.8 GeV, 100 Hz NC Brazil: SIRIUS EU XFEL 2017 LCLS France: ESRF II Sweden: MAX-IV 17.5 GeV, 3000 x 10 Hz SC BES Light Sources Ring Upgrades New Rings Upgraded & New FELs 5 USA Response: BES Community Consensus Building Guided by BESAC BESAC Report on Facility Upgrades Subcommittee on BES Facility Upgrade Prioritization Agenda 14-16 April 2016 Approved by the Basic Energy MEETING FORMAT: Sciences Advisory Committee • Lab Presentation of Upgrade (90 min) on June 9, 2016 • Subcommittee Q&A with Lab (60 min) • Subcommittee Discussion of Upgrade (60 min) Report of the BESAC Subcommittee o Thu PM: LBNL ALS-U on Future X-ray Light o Fri AM: ANL APS-U Sources o Fri PM: ORNL PPU/STS o Sat AM: SLAC LCLS-II-HE o Sat PM: Subcommittee Discussion & Closeout Approved by the Basic Energy Sciences Advisory Committee Chair: John Hemminger on July 25, 2013 BESAC Report Also Included Neutron Sources USA Response: BESAC Report on Light Source Facility Upgrades (June 2016) Storage Rings FEL Project ANL LBNL SLAC APS-U ALS-U LCLS-II-HE Project Scope Hard X-ray Soft X-ray High Rep-Rate, ~Diffraction Limited ~Diffraction Limited High Energy 6 GeV Multi-Bend Achromat 2 GeV Multi-Bend X-ray FEL, (MBA) Ring Achromat (MBA) Ring 8 GeV SC Linac Current Status APS is operational since ALS is operational since LCLS is operational since of Facility 1996; ring will be replaced 1993; ring will be replaced 2010; LCLS-II is under construction Worldwide EU Sweden EU ESRF MAX-IV XFEL Competition Germany Brazil Japan PETRA 3,4 SIRIUS SACLA Japan CH Korea SPring-8-II SLS-II PAL XFEL China CH BLS Swiss FEL Dark Time ~1 yr ~0.75 yr 0 yr Status FY2017 CD-3b CD-0 CD-0 The ALS-U, APS-U & LCLS-II-HE proposals were each deemed “absolutely central to contribute to world leading science & ready to initiate construction” 7 Storage Rings & Free Electron Lasers are Complementary Parameter Storage Rings FELs Beam Stability Excellent Very Good Number of Beamlines Up to 70+ 1-5 Brightness (Ave, Peak) (High, Low) (Up to Very High, Extreme) Transverse Coherence Partial-Full Full (@ Saturation) Longitudinal Coherence Poor Moderate (SASE)-Very Good (seeding) Pulse Time Structure ~10 msec ~mJ LCLS ~fs Pulse Energy ~mJ ~10-250 ps Eu-XFEL ~fs ~ns (FLASH) ~µsec ~0.1-1 mJ ~nJ, 0.1%BW LCLS-II 8 New Sources Will Provide Enhanced Transverse & Longitudinal Coherence Realistic Partial Idealized Full Realistic Full Coherence Advantages Level Coherence Multi-Mode Point Source Gaussian Laser Mode Coherent Diffractive Imaging, y (Spherical Waves) Ptychography & Nanoprobes x Transverse (Spatial Profile) (Spatial λ ∆푥, ∆푦 → 0 λ ∆푥 ∙ ∆θx > 4π ∆x ∙ ∆θx = 4π Imaging w/o Lenses Noisy Pulse Monochromatic Wave Train Gaussian Laser Pulse FEL SASE vs Seeded Spectrum E(t) E(t) E(t) I 휔 I 휔 t t t 휔 Longitudinal 휔 Δ휔 Δ휔 (Temporal Profile) (Temporal λ Maximize Number of Photons c ∆t ∙ > λ ∆ω → 0, ∆t → ∞ c ∆t ∙ = 4π 휔 4π 휔 in Minimum BW 9 Physics & Technology for Maximizing the Photon Beam Brightness, Bave Rings ~ 1022 FELs ~ 1025 Stimulated Emission from a Self Bunched Beam (SASE) Spontaneous Emission from a Random Beam spon Ne N ph Ne 137 6 푁푒/푐표표푝 ≈ 10 푠푡푚 6 푠푝표푛 푁푝ℎ ≈ 10 푁푝ℎ On Axis Injection freprate photons / pulse / 0.1% BW Bave 2 Bunch-by-Bunch 4 ex Lx ey Ly or Bunch Trains SC RF CW Linac (1.3 GHz) Diffraction Limit 2 2 High Brightness E Lx Ly e N 2,3 7,9 2 x 3 , MBA High Rep Rate Ndipole Photoinjector Multi-Bend Achromat (MBA) Bave 10 Bpeak FEL10 Bave e freprate Z = 25 m Z = 50 m Z = 75 m 10 Advanced Photon Source Upgrade (APS-U) at ANL Project Developments: APS-U MBA-7 lattice uses 7 bending magnets/sector (was 2) . Design optimized to provide penetrating high- energy x-rays . MBA-7 lattice incorporating reverse bends to reduce emittance from 67pm to 41pm . Beamline proposal selection and roadmap complete . Technical prototypes well along; Preliminary Design Report underway; ready for next step Small-Beam Scattering & Coherent Scattering & Imaging Resolution @ Speed Spectroscopy . Highest possible spatial . Mapping all of the critical atoms in a . Nanometer imaging with chemical resolution: 3D visualization; cubic millimeter and structural contrast; few- imaging of defects, disordered . Detecting and following rare events atom sensitivity heterogeneous materials . Multiscale imaging: enormous fields . Room-temperature, serial, single- . XPCS to probe continuous of view with high resolution; pulse pink beam macromolecular processes from nsec onward, crystallography opening up 5 orders of magnitude in time inaccessible today, Missing atom 11 Advanced Light Source Upgrade (ALS-U) at LBNL Goal: High CW soft x-ray coherent flux necessary to resolve New Accumulator Ring nm-scale features & enable real-time observation of chemical processes & materials as they function Project Developments: • Replace the existing MBA-3 ring with a new MBA-9 ring • New accumulator ring for on-axis bunch train injection New ALS-U MBA-9 Ring • Critical Decision 0 approved on Sept 2016 Map nano-objects’ 3D electronic, Control chemical kinetics in Deploy spin, quantum, and chemical, & magnetic structure confined spaces topological materials Understand Roles of Heterogeneity Master Hierarchical Architectures Harness Coherence in Light & Matter •Connect spatial, •Reveal relationships •Probe electronic chemical, & temporal between nanoscale structure of single heterogeneity with chemical structures domains and gated real-time movies & the kinetic processes structures of they support complex materials •Potential benefit – optimize •Potential benefit – chemical •Potential benefit – ultralow-power material processes & properties, catalytic reactors, solar fuel computing, new classes of e.g., low carbon footprint concrete production, water purification sensors, spin-based devices 12 LCLS Performance Has Advanced Far Beyond Its Baseline Parameters Since 2009 Expanded photon energy range, Generation of few-fs x-ray pulses 0.25 – 12.8 keV & polarization control & measurements with XTCAV From SASE fluctuations to controlled Creation of multiple options for pulse width & spectrum (seeding) 2-pulse, 2-color x-rays SASE spectrum Seeded spectrum ~ 20 eV ~ 0.5 eV SASE Seeded 40x Increase in Temporal Coherence! 13 Linac Coherent Light Source II (LCLS-II) at SLAC Project Scope & Status: • 200-5,000 eV x-rays at up to 1 MHz (from 120 Hz) • Double the energy reach of LCLS to 25 keV • 4 GeV CW SC linac, 2 new variable gap IDs • CD-2, CD-3 approved in 2016 Charge dynamics on Emergent phenomena in Molecular dynamics with fundamental timescales quantum materials exquisite resolution . Reveal coupled electronic and . Connect spontaneous fluctuations, . Measure element-specific, local nuclear motion in molecules dynamics and heterogeneities on chemical structure and bonding multiple length- and time-scales to . Capture the initiating events of . Study efficient, robust, selective bulk material properties charge transfer chemistry with photo-catalysts sub-fs resolution . Study interacting degrees of freedom (e.g. unconventional superconductors) lattice spin charge orbital 14 LCLS-II-HE is Needed to Probe Structural Dynamics at the Atomic Scale (~1 Å) Electronic dynamics Atomic-scale structure Project Scope & Status: 1026 LCLS-II-HE • Extend CW-SCRF linac from 4 to 8 GeV 1025 LCLS-II Eu-XFEL ) 24 W 10 s B ~300x s e • Provide high rep-rate capability beyond 1Å (>12 keV) % 1 n . t DLSR limit 0 h / 23 2 g 10 i d r a r B m e • Injector development to enable lasing up to 20 keV / 2 g 22 a m 10 r m e / v s / A LCLS h • Average coherent x-ray power (spatial & temporal) is p 21 ( 10 DLSR(s) transformative 1020 0.2-1.1 km, 2-6 GeV 6.3 km, 9 GeV 1019 • CD-0 approved in Dec 2016 2 4 6 8 10 12 14 16 18 20 Photon Energy (keV) Heterogeneity & complexity in Dynamicsof biomolecules and Fluctuationsin the ground state ground & excited states molecular machines and spontaneous evolution .
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