A5060193619- Particle Accelerators and Free-Electron Lasers
- Advanced X-ray Imaging Techniques
- Particle accelerators and beam dynamics
- Laser-Matter Interactions and Applications
- Atomic and Molecular Physics
- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Mass Spectrometry Techniques and Applications
- Advanced Electron Microscopy Techniques and Applications
- Superconducting Materials and Applications
- High-pressure geophysics and materials
- Plasma Diagnostics and Applications
- Molecular Junctions and Nanostructures
- Adrenal and Paraganglionic Tumors
- Scientific Computing and Data Management
- Laser Design and Applications
- Gyrotron and Vacuum Electronics Research
- Crystallography and Radiation Phenomena
- Advanced Fiber Laser Technologies
- Magnetic confinement fusion research
- Advancements in Photolithography Techniques
- Advanced Materials Characterization Techniques
- Semiconductor materials and devices
- Electromagnetic Simulation and Numerical Methods
- Solid State Laser Technologies
IPG Photonics (United States)
2022
Linac Coherent Light Source
2011-2021
SLAC National Accelerator Laboratory
2009-2021
Menlo School
2009-2016
Elettra-Sincrotrone Trieste S.C.p.A.
2011
Stanford University
2008-2010
Stanford Synchrotron Radiation Lightsource
2010
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
1998-2000
CEA Paris-Saclay
1998-2000
The Linac Coherent Light Source (LCLS) is an x-ray free-electron laser project presently in a commissioning phase at the SLAC National Accelerator Laboratory. We report here on very low-emittance measurements made low bunch charge, and few femtosecond length produced by LCLS compressors. Start-to-end simulations associated with these beam parameters show possibilities of generating hundreds GW 1.5 \AA{} wavelength nearly single longitudinally coherent spike nm 2-fs duration.
The Linac Coherent Light Source is a SASE x-ray free-electron laser (FEL) project presently under construction at SLAC [J. Arthur et al., SLAC-R-593, 2002.]. injector section, from drive and rf photocathode gun through first bunch compressor chicane, was installed in the fall of 2006. initial system commissioning with an electron beam completed August 2007, goal 1.2-micron emittance 1-nC demonstrated. second phase commissioning, including full linac, planned for 2008, FEL 2009. We report...
The ultrafast evolution of microstructure is key to understanding high-pressure and strain-rate phenomena. However, the visualization lattice dynamics at scales commensurate with those atomistic simulations has been challenging. Here, we report femtosecond x-ray diffraction measurements unveiling response copper laser shock-compression peak normal elastic stresses ~73 gigapascals (GPa) strain rates 10(9) per second. We capture from a one-dimensional (1D) 3D plastically relaxed state within...
The very bright electron beam required for an x-ray free-electron laser (FEL), such as the linac coherent light source (LCLS), is susceptible to a microbunching instability in magnetic bunch compressors, prior FEL undulator. uncorrelated energy spread LCLS can be increased by order of magnitude provide strong Landau damping against without degrading performance. To this end, ``laser-heater'' system has been installed injector, which modulates 135-MeV with IR-laser short undulator, enclosed...
Nonsequential double ionization of several molecules such as ${\mathrm{N}}_{2},{\mathrm{CO}}_{2},{\mathrm{C}}_{2}{\mathrm{H}}_{2},$ and ${\mathrm{C}}_{3}{\mathrm{H}}_{4}$ in strong laser fields has been unambiguously identified from the ion-yield measurements comparison with a sequential model ${10}^{13}--{10}^{15} \mathrm{W}/{\mathrm{cm}}^{2}$ intensity range. This effect is observed mainly using linearly polarized light. In circular polarization, nonsequential might be present, for...
The linac coherent light source (LCLS) is a self-amplified spontaneous emission (SASE) free-electron laser (FEL) operating at fundamental photon energies from 0.5 to 10 keV. Characterization of the higher harmonics present in FEL beam important users, for whom harder x rays can either extend useful wavelength range or increase experimental backgrounds. We measurements power both second and third harmonics, compare results expectations simulations. also studies transport harmonic as function...
In this Letter we report the experimental demonstration of a new temporal shaping technique for x-ray free-electron lasers (FELs). This is based on use spectrally shaped infrared (IR) laser and allows optical control generation process. By accurately manipulating spectral amplitude phase IR laser, can selectively modify electron bunch longitudinal emittance thus controlling duration resulting pulse down to femtosecond time scale. Unlike other methods currently in use, directly applicable...
We report the demonstration of optical compression an electron beam and production controllable trains femtosecond, soft x-ray pulses with Linac Coherent Light Source (LCLS) free-electron laser (FEL). This is achieved by enhanced self-amplified spontaneous emission a 2 μm dechirper device. Optical was modulating energy then compressing chicane, resulting in high current spikes on which we observe to lase. A used selectively control lasing region beam. Field autocorrelation measurements...
Understanding the emergence of collective behavior in correlated electron systems remains at forefront modern condensed matter physics. Disentangling degrees freedom responsible for can lead to insights into microscopic origins emergent properties and phase transitions. Utilizing an optical pump, resonant soft x-ray diffraction probe we are able track, real time, dynamics charge density wave (CDW) ${\mathrm{TbTe}}_{3}$, a model system that violates traditional views Fermi surface nested CDW....
The Facility for Advanced Accelerator and Experimental Tests (FACET) at SLAC installed a 10-TW Ti : sapphire laser system pre-ionized plasma wakefield acceleration experiments. High energy (500 mJ), short (50 fs) pulses of 800 nm light 1 Hz are used the FACET experimental area to produce column. stretched 250 fs before injection into vapor cell, where is focused by an axicon lens form column that can be sustained over desired radius length. A 20 GeV electron bunch interacts with this...
Laser-induced molecular coulomb explosion of ${\mathrm{N}}_{2}$ and ${\mathrm{CO}}_{2}$ is studied experimentally using linearly circularly polarized laser light in the ${10}^{15}{\mathrm{W}/\mathrm{c}\mathrm{m}}^{2}$ intensity range at $\ensuremath{\lambda}=800\mathrm{nm}.$ The fragmentation kinetic energy releases are found to be identical both cases two different experimental methods. These results show that relaxation independent respective directions electric field internuclear axis....
Non-sequential double ionization of and is observed using a linear polarized 50 fs laser pulse at in the intensity range. The charge separation channels follow similar dependences as detected dication for different final kinetic energy releases . These experimental results show that two-electron ejection occurs short internuclear distance following Franck - Condon principle molecular decay case come from same complex resulting excitation.
We present a new measurement of lattice disassembly times in femtosecond-laser-heated polycrystalline Au nanofoils. The results are compared with molecular dynamics simulations incorporating highly optimized, embedded-atom-method interatomic potential. For absorbed energy densities $0.9--4.3\text{ }\text{ }\mathrm{MJ}/\mathrm{kg}$, the agreement between experiment and simulation reveals single-crystal-like behavior homogeneous melting corroborates applicability potential nonequilibrium warm...
The production of ${\mathrm{C}}^{Z+}, {\mathrm{N}}^{Z+}$, and ${\mathrm{O}}^{Z+}$ multicharged atomic ions up to $Z=4$ is investigated using the laser-induced multiple ionization small molecules in gas phase ${10}^{15}--{10}^{16}\ensuremath{-}{\mathrm{W}/\mathrm{c}\mathrm{m}}^{2}$ laser intensity range. For built with a single C, N, or O atom hydrogen atoms such as ${\mathrm{CH}}_{4}{,\mathrm{ }\mathrm{NH}}_{3}$, ${\mathrm{H}}_{2}\mathrm{O}$, $Z=3$ 4 ion yields are systematically weaker than...
Requirements for the LCLS injector drive laser present significant challenges to design of system. While progress has been demonstrated in spatial shape, temporal shape,UV generation and rep-rate, a that meets all specifications simultaneously yet be demonstrated. These are compounded by stability reliability requirements. The transport system installed tested. We will report on current operational state plans future improvements.
We have performed extensive numerical studies of Coulomb explosion small molecules such as ${\mathrm{CO}}_{2}$ and ${\mathrm{N}}_{2}\mathrm{O}$ with the help a hydrodynamic model, which allows one to deal many-electron systems in intense laser fields. The predicted kinetic energy releases fragmentation channels are good agreement measured energies, using realistic molecular excitation condition parameters.
The linac coherent light source (LCLS) is a SASE X- ray free-electron laser (FEL) project presently under construction at SLAC [1]. injector section, from drive-laser and RF photocathode gun through first bunch compressor chicane, was installed in fall 2006. Initial system commissioning with an electron beam taking place during the spring summer of 2007. second phase construction, including full linac, will begin later, We report here on experience gained machine commissioning, gun, booster...