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Bright Lights on the Horizon. Ralf Röhlsberger HASYLAB @ DESY, Hamburg, Germany. Future Perspectives for Nuclear Resonant Scattering of Synchrotron Radiation. The Evolution of Brilliance Upgrade of Existing Sources Construction of New Sources: PETRA III and the XFEL.
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Bright Lights on the Horizon Ralf Röhlsberger HASYLAB @ DESY, Hamburg, Germany Future Perspectives for Nuclear Resonant Scattering of Synchrotron Radiation • The Evolution of Brilliance • Upgrade of Existing Sources • Construction of New Sources: • PETRA III and the XFEL
PETRA-III Upgrade http://www-hasylab.desy.de/facility/upgrade/main.htm
Schedule • Submission of the Technical Design Report: March 2004 • Selection of the phase I beamlines: early Summer 2004 • Start of beamline R&D, prototyping: mid 2004 • Start of detailed beamline planning: end 2004/2005 user workshops on detailed beamline design • Start of component production: 2006 • Start of reconstruction: mid 2007 • Installation of first beamlines: mid 2008 • Start of user operation: 2009
Insertion Devices and Beamlines 13 independent undulators 1 undulator of 20 m length Technical Design Report submitted: 22 experimental stations proposed, including Nuclear Resonant Scattering PETRA III - Facts and Figures Storage Ring Particle energy = 6 GeV Current = 100 mA (200 mA) Emittance = 1 nmrad Operation Number of bunches: 40 – 960 Bunch distance: 192 ns – 8 ns Top-up operation mode
NRS Beamline Proposed at PETRA-III 20 m undulator Revolver – type with two magnet structures: 1) optimized for 14.4 keV (fundamental) 2) optimized for 21.5 – 30 keV (third harmonics) General Experiment Support Cryostats, high-magnetic fields, high-pressure cells, furnaces, detectors (0,1,2 - dimensional), electronics, mechanical components, lasers
NRS from Isotopic Probe Layers using Microfocused Beams Spot sizes well below 1mm can be reached by application of focusing mirror optics Magnetic Properties : Spin Structure and Magnetic Correlations in thin films and nanoparticles Dynamic Properties : Phonons at interfaces and in nanoparticles Nuclear resonant photon correlation spectroscopy
High-Resolution Monochromators at PETRA-III Yu. V. Shvyd‘ko (2003)
Limits of Storage – Ring Based Sources Beam properties reflect the equilibrium dynamics of particles in the ring, resulting from averaging over all revolutions Particles are re-cycled Design study: The Ultimate Storage Ring (USR) Development of New Radiation Sources Radiation is generated by single bunches passing through an undulator Energy – Recovery Linear Accelerator (ERL) Sub-Picosecond Pulsed Source (SPPS) X-ray Free Electron Laser (XFEL)
SASE FEL Undulator e- X-Ray Free-Electron Lasers • Synchrotron radiation • low emittance electron beam • relativistic electron energy • periodic acceleration of electron in magnetic field of an undulator • collimated radiation • tunable by electron energy & magnetic field • ... at x-ray wavelengths • no efficient reflectors exist • lasing in a ‚single-pass‘ • Self-Amplified Spontaneous Emission (SASE)
low gain exponential gain (high-gain linear regime) P(z) = Po exp(z/Lgain) non-linear log (power) gain ~ 105 saturation length ~ 10 Lgain duration, length SASE exponential growth and saturation
undulator entrance half-way saturation full saturation Electron bunch modulation GENESIS - simulation for TTF parameters Courtesy - Sven Reiche (UCLA)
Time structure of the XFEL radiation Single bunches. Few bunches. Longtrains.
Radiation parameters Compared to 3rd generation synchrotron radiation facilities, the gain factors are • Peak brilliance 109 (FEL) • 104 (spont.) • Average brilliance 104 (FEL) • Degeneracy 109 (FEL) 109 Total increase 106 FEL gain 103 e-properties undulator length
Published science cases for FEL radiation • Ultrashort duration of X-ray pulses • High number of photons per pulse • Coherent x-ray radiation • Atoms, molecules, cluster • Plasma physics • Hard-condensed matter • Surface & interface studies • Materials science • Chemistry • Biology • Nonlinear phenomena & • quantum optics • FEL physics http://slac.stanford.edu/lcls http://xfel.desy.de
2012 European XFEL (Hamburg) 2008 LCLS (Stanford) 2004 VUV-FEL @ TTF (Hamburg) Roadmap towards an 0.086 nm XFEL 2000-2002 TTF-1 (Hamburg) 2000-2001 LEUTL (Argonne) 1980 initial paper
The European XFEL project • Original proposal (March 2001) part of the TESLA project. • In October 2002 an standalone version was proposed • Germany agreed to propose a site and to cover 50% of the building cost. • Technical parameters are currently reconsidered. ~ 2000m ~ 1200m 3 FEL and 2 beamlines for spontaneous synchrotron radiation with 10 independent experimental stations
Towards the European XFEL Feb 2003 BMBF indicates ‚green light‘ for European XFEL Oct 2003 European Strategy Forum for Research Infrastructures evaluates Technical challenges Dec 2003 XFEL enters EU Quickstart programme Jan 2004 Formation of an European steering group • Working groups on technological issues • Working groups on administrative issues • Update of scientific case End 2004 Start plan approval procedure at DESY Workshops to define user/science requirements Early 2005 European agreement on XFEL project Start of project • Start of construction 2012 Start of commissioning
10-15 s Valence state excitations Te-h >> TL non-thermal Carrier-phonon scattering Te-h, TL 10-12 s Equilibration (Te-h ~ TL) Phonon-phonon scattering 10-9 s 10-6 s Diffusion, melting, ablation thermal Ultrafast Processes
NRS Experiments at the XFEL Non-equilibrium phenomena Pump-probe investigations of dynamical phenomena Excitations in artificial spin chains, solitons Fast magnetic switching Magnon spectroscopy, Single – particle imaging Use of complementary techniques Neutron scattering, Magnetic x-ray scattering, Magneto-optics, Inelastic x-ray scattering, …