X-ray has been an important scientific tool ever since its discovery in the 1890s. X-ray used to be generated by synchrotron machines, which are large and expensive devices. However, laser-based particle acceleration offers a way to reduce the size and cost of hard-X-ray sources. Scientists have now developed a simple scheme that produces a bright flash of hard-X-rays by using a single laser pu...

The possibility of producing ultrashort (fs) X-ray pulses through Thomson scattering of high power laser pulses off relativistic electron bunches generated by plasma-based accelerators is discussed. The electron bunches are produced with either a self-modulated laser wakefield accelerator (SM-LWFA) or through a standard laser wakefield accelerator (LWFA) with optical injection. For a SM-LWFA (L...

We have generated a laser average output power of 2 microW at a wavelength of 13.9 nm by operating a tabletop laser-pumped Ni-like Ag laser at a 5 Hz repetition rate, using a solid helicoidal target that is continuously rotated and advanced to renew the target surface between shots. More than 2 x 10(4) soft-x-ray laser shots were obtained by using a single target. Similar results were obtained ...

We are developing Laser Super Cavity for compact X-ray generator based on Inverse Compton Scattering with several tens MeV electron beam. The laser supercavity increases the laser power and makes small laser beam size at the collision point with the electron beam. A FabryPerot cavity as the laser supercavity has been tested at the KEK-ATF (Accelerator Test Facility) and the design for the incre...

We report anomalous fringe shifts observed in soft X-ray laser interferograms of laser-created Al plasmas. This clear experimental evidence shows that the contribution of bound electrons can dominate the index of refraction of laser-created plasmas at soft X-ray wavelengths, resulting in values greater than 1. The comparison of measured and simulated interferograms shows that this results from ...

We have constructed a scanning soft-x-ray microscope that uses a laser-produced plasma as the soft-x-ray source and normal-incidence multilayer-coated mirrors in a Schwarzschild configuration as the focusing optics. The microscope operates at a wavelength of 14 nm, has a spatial resolution of 0.5 microm, and has a soft-x-ray photon flux through the focus of 10(4)-10(5) sec(-1) when operated wit...

We report the generation of MeV x rays using an undulator and accelerator that are both driven by the same 100-terawatt laser system. The laser pulse driving the accelerator and the scattering laser pulse are independently optimized to generate a high energy electron beam (>200  MeV) and maximize the output x-ray brightness. The total x-ray photon number was measured to be ∼1×10(7), the source ...

We present clear experimental evidence showing that the contribution of bound electrons can dominate the index of refraction of laser-created plasmas at soft x-ray wavelengths. We report anomalous fringe shifts in soft x-ray laser interferograms of Al laser-created plasmas. The comparison of measured and simulated interferograms shows that this results from the dominant contribution of low char...

The Coulomb explosion of the octamer water cluster has been studied employing time-dependent density functional theory explicitly accounting for the laser field and thus not imposing any constraint on the interaction between the laser pulse and the cluster. We focus on the effects of electron density changes in the system under high-intensity (10(16) and 10(15) W cm(-2)) soft X-ray laser pulses...