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AMO Early Science Capability. AMO will be first experiment online @ LCLS Planning for commissioning / first experiments in August 2009 Adaptable to reality of source performance – i.e. planning for FEL and spontaneous source Currently in final design phase (>50% of drawings complete).
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AMO Early Science Capability AMO will be first experiment online @ LCLS Planning for commissioning / first experiments in August 2009 Adaptable to reality of source performance – i.e. planning for FEL and spontaneous source Currently in final design phase (>50% of drawings complete)
Scientific Goals of AMO Program • Investigate multiphoton and high-field x-ray processes in atoms, molecules and clusters • Multi-photon ionization/excitation in atoms/molecules/clusters • Accessible intensity on verge of high-field regime • Study time-resolved phenomena in atoms, molecules and clusters using ultrafast x-rays • Inner-shell side band experiments • Photoionization of aligned molecules • Temporal evolution of state-prepared systems
AMO studies fundamental interactions • Through years of investigation, we have a pretty good idea what happens when we hit an atom with an x-ray? • Consider Ne atoms and ~1keV photons • Photoabsorption • Photoelectron • Auger • fluorescence
AMO @ LCLS • What happens when we illuminate atoms with high peak power of LCLS? ?? • Multiple ionization • Multiphoton ionization • Tunneling ionization • Subsequent de-excitation dynamics
AMO Instrumentation • Pulse Picker • Focusing optics • High Field Physics Experiment • Diagnostics • Synchronized pulsed laser
What’s there July 2009? • Focusing Optics • High Field Physics Chamber • Pulsed gas jet • Ion TOF (Wiley McLaren type) • Electron TOFs • Diagnostics • Effusive gas jet • Magnetic bottle TOF • Beam screens • Synchronized Laser
And what’s commissioned later ? • Pulse picker(12/09) • High Field Physics Chamber • Velocity map imaging ion spectrometer(10/09) • Momentum resolving ion spectrometer (reaction microscope/ColTRIMS)(2/10) • X-ray spectrometers(1/10) • Diagnostics • Pulse energy monitor(11/09)
A little more detail – focusing optics • Built by LBNL as a full assembly Focus in experimental chamber or diagnostics Focus beam to ~ 1um diameter
AMO Design – focusing optics • Peak intensity depends on size of beam focus – accessible physics depends on intensity • LBNL mirror bender design
Ne charge state vs Intensity Rohringer & Santra, PRA 76, 033416 (2007)
Probable Ne Charge State with hv Rohringer & Santra, PRA 76, 033416 (2007)
AMO Interaction region • Five electron spectrometers & one ion spectrometer
Xe ions as function of irradiance • Focused 93 eV photons to 2.6um into ambient Xe • Collected ion signal by ion TOF A.A. Sorokin et al., PRL 99, 213002 (2007)
Multiphoton Photoelectron Spectroscopy • Recent measurements of electrons from Ar clusters at FLASH show that direct multistep ionization of cluster creates higher charge states with short l radiation (38.5 eV) C. Bostedt, et al., PRL 100, 133401 (2008).
Diagnostics - Magnetic Bottle • Magnetic Bottle being designed (and possibly built) by Ohio State University under contract with Louis DiMauro Very high electron collection efficiency (~2p) Useful as a measure of LCLS spectrum by converting hn to electron KE Also unique experimental capability
Pulse Stretcher 30 fs Bandwidth 30 fs Mode Locked Ti:sapp @ 800 nm 5 W Nd:YVO4 Regenerative Amplifier 1kHz, <5 mJ 30W Nd:YLF Pump Laser @ 527nm 1.2 kHz Pulse Cleaner Laser Hall Hutch 2 Optical Transport Optical Transport Optical Transport Pulse Compressor (Single Grating) Harmonics Experiment Chambers NEH Laser
Diagnostic - Temporal Resolution Two photons of different energy in interaction region at same time can result in multiphoton ionization (i.e. FLASH FEL & laser) Phenomenon provides a means to measure temporal overlap of two pulses – i.e. providing measure of temporal overlap between LCLS & laser • Measured relative jitter between two beams of 250fs using Xe 5p photoionization P. Radcliffe et al, APL, 90, 131108, 2007.
ISMS for the AMO Instrument • Define scope of work • Using LCLS design review process - documentation and reviews • Analyze hazards • Working with SLAC safety experts • Prepared Preliminary Hazards Assessment Document (PHAD) for AMO instrument • Develop and implement hazard controls • With advice and review by SLAC safety committees • Build the instrumentation • Re-analyze hazards
Unique Hazards Identified for AMO • High pressure gas bottles (samples) connected to vacuum chamber • Health hazard gases will be used in some experiments • High power laser system with multiple wavelengths • High magnetic field in magnetic bottle spectrometer • Numerous high voltage supplies
The Path Forward • Preliminary Design Review Completed • Finish detailing high field physics chamber, diagnostics • Finalize Design & Review – June 08 • Procurement phase – Jul-Dec 08 • Assembly & Testing – Jan-Jun 09 • Readiness review – July 09 • Ready for first light – July 09 Thanks - lots of help from engineering, controls, etc.
Commissioning vs First Experiments • First experiments need only some of the instrumentation’s capability • i.e. with focusing optics, gas jet & ion spectrometer could do multiphoton ionization expt. • OR with magnetic bottle & laser could study temporal overlap with LCLS – (may even be possible without lasing) • Managing commissioning vs experiment – pressure for both !!
The End AMO Proposal Study Workshop – June 2-3, 2008 @ SLAChttp://www-conf.slac.stanford.edu/amo/2008