Inverse Compton Scattering X-ray Source Research Articles

A Transportable End-station for a Novel Inverse Compton Scattering X-ray Source

To bridge the gap between lab-based high-resolution X-ray tomography (micro-CT) and synchrotron-based micro-CT, lab-scale accelerator-based or Inverse Compton Scattering (ICS) X-ray sources are a promising technology. In the scope of a large-scale project funded by the European Regional Development Fund (Interreg Grensregio), a new ICS source dubbed Smart*Light is being developed at TU Eindhoven. In this work, we present the advantages of this source compared to existing systems and its potential in industrial X-ray CT.

Inverse Compton scattering x-ray source from laser electron accelerator in pure nitrogen with 15 TW laser pulses

Using 15 TW laser pulses, we present a systematic investigation on tabletop inverse Compton scattering (ICS) hard x-ray source based on the self-synchronized combination of laser-driven pure nitrogen plasma accelerator and plasma mirror (PM). In the scheme of pure nitrogen medium and ionization induced injection, the laser wake-field acceleration (LWFA) is performed at a lower laser intensity of a0 ∼ 2 and a lower plasma density of ne ∼ 8 × 1018 cm−3, which lead to the weak evolution of beam profile and high energy transmission rate of 95%. We found the quality of electron beam is insensitive to the focus position of the laser pulse near the tail of gas jet, so it becomes possible to place the focus close to the PM. Tunning the collision point of accelerated electron bunch and reflected laser beam to the optical focal spot, ICS is dramatically increased. Ultimately, the produced ICS x-rays have the yield of 4.5 × 107. And the photon number exceeding 200 keV is about 1.2 × 107. Demonstrated by our results, stable and high yield of x-ray source in hundreds of keV range could be achieved via all-optical ICS driven by only ten terawatt lasers. This reduces the threshold of obtaining high-energy femtosecond x-rays.

High duty cycle inverse Compton scattering X-ray source

Inverse Compton Scattering (ICS) is an emerging compact X-ray source technology, where the small source size and high spectral brightness are of interest for multitude of applications. However, to satisfy the practical flux requirements, a high-repetition-rate ICS system needs to be developed. To this end, this paper reports the experimental demonstration of a high peak brightness ICS source operating in a burst mode at 40 MHz. A pulse train interaction has been achieved by recirculating a picosecond CO2 laser pulse inside an active optical cavity synchronized to the electron beam. The pulse train ICS performance has been characterized at 5- and 15- pulses per train and compared to a single pulse operation under the same operating conditions. With the observed near-linear X-ray photon yield gain due to recirculation, as well as noticeably higher operational reliability, the burst-mode ICS offers a great potential for practical scalability towards high duty cycles.

High repetition-rate inverse Compton scattering x-ray source driven by a free-electron laser

We describe a hybrid free-electron laser (FEL)/inverse Compton scattering (ICS) system that can be operated at very high repetition rates and with higher average gamma-ray fluxes than possible from ICS systems driven by J/kHz laser systems. Also, since the FEL system can generate 100 mJ class photon pulses at UV wavelengths, the electron beam energy can be lower than for systems driven with ∼micron wavelength lasers for attaining gamma rays of similar energy.

Design of a 4.8-m ring for inverse Compton scattering x-ray source

In this paper we present the design of a 50 MeV compact electron storage ring with 4.8-meter circumference for the Tsinghua Thomson scattering x-ray source. The ring consists of four dipole magnets with properly adjusted bending radii and edge angles for both horizontal and vertical focusing, and a pair of quadrupole magnets used to adjust the horizontal damping partition number. We find that the dynamic aperture of compact storage rings depends essentially on the intrinsic nonlinearity of the dipole magnets with small bending radius. Hamiltonian dynamics is found to agree well with results from numerical particle tracking. We develop a self-consistent method to estimate the equilibrium beam parameters in the presence of the intrabeam scattering, synchrotron radiation damping, quantum excitation, and residual gas scattering. We also optimize the rf parameters for achieving a maximum x-ray flux.

Electron bunch energy and phase feed-forward stabilization system for the Mark V RF-linac free-electron laser

An amplitude and phase compensation system has been developed and tested at the University of Hawai'i for the optimization of the RF drive system to the Mark V free-electron laser. Temporal uniformity of the RF drive is essential to the generation of an electron beam suitable for optimal free-electron laser performance and the operation of an inverse Compton scattering x-ray source. The design of the RF measurement and compensation system is described in detail and the results of RF phase compensation are presented. Performance of the free-electron laser was evaluated by comparing the measured effects of phase compensation with the results of a computer simulation. Finally, preliminary results are presented for the effects of amplitude compensation on the performance of the complete system.

Quantitative phase retrieval with picosecond X-ray pulses from the ATF Inverse Compton Scattering source

Quantitative phase retrieval is experimentally demonstrated using the Inverse Compton Scattering X-ray source available at the Accelerator Test Facility (ATF) in the Brookhaven National Laboratory. Phase-contrast images are collected using in-line geometry, with a single X-ray pulse of approximate duration of one picosecond. The projected thickness of homogeneous samples of various polymers is recovered quantitatively from the time-averaged intensity of transmitted X-rays. The data are in good agreement with the expectations showing that ATF Inverse Compton Scattering source is suitable for performing phase-sensitive quantitative X-ray imaging on the picosecond scale. The method shows promise for quantitative imaging of fast dynamic phenomena.