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Recently there has been considerable interest in the Thomson scattering of intense laser from relativistic electron beams, and a new kind of x-ray source named laser synchrotron source (LSS) has been discussed based on this mechanism which is expected to have extremely good performances. In order to verify this theory, an experiment is going to be carried out by our group using a frequency-doubled yttrium–aluminum–garnet laser and a 25 MeV electron beam generated by the accelerator in the Applied Department of the Institute of High-Energy Physics. In this article some theoretical results have been calculated for this experiment, including the scattered x-ray’s wavelength and intensity distribution. The results at 180° and 90° have been given and the 180° result should be very close to the experimental geometry of 178.5°. In Sec. III, figures of the spatial distribution of x-ray are drawn. The future of LSS is prospected finally in Sec. IV.

A laser ion source based on laser resonant ionization at the outlet of a helium jet was proposed for on-line isotope separator of the Heavy Ion Research Facility in Lanzhou, China a few years ago. An off-line test setup was built at Tsinghua University. The initial experimental results of the setup indicate that carrying neutral Na monoatoms to the outlet of a helium jet and directly ionizing the Na atoms in the helium jet beam by laser resonant ionization is very efficient. It provides an effective method for producing element selected ions with high efficiency, low background, and short transporting time. It is applicable for the separation of various elements, and is particularly useful for refractory elements.

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The equilibrium geometry, harmonic frequency and bond dissociation energy of lanthanum monofluoride have been calculated using Density-Functional Theory (DFT), post-HF methods MP2 and CCSD(T) with the energy-consistent relativistic effective core potentials. The possible electronic state and reasonable dissociation limit of the ground state of LaF are determined based on atomic and molecular reaction statics. Potential energy curve scans for the ground state X1Σ+ have been performed at B3LYP and CCSD(T) levels, due to their better results of harmonic frequency and bond dissociation energy. We find that the potential energy calculated with CCSD(T) is about 0.6 eV larger than the bond dissociation energy, when the internuclear distance is as large as 0.8 nm. The problem that single-reference ab initio methods do not meet dissociation limit during calculations of lanthanide heavy-metal elements is analyzed. We propose the calculation scheme to derive the analytical Murrell-Sorbie potential energy function. Vibrotational spectroscopic constants Be, ωe, ωeχe, αe, βe, De and He obtained by the standard Dunham treatment coincide well with the results of rotational analyses on spectroscopic experiments.