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Short period, high field undulators are used to produce hard X-rays on synchrotron radiation based storage ring facilities of intermediate energy and enable short wavelength Free Electron Laser. Cryogenic permanent magnet undulators take benefit from improved magnetic properties of RE2F e14B (Rare Earth based magnets) at low temperatures for achieving short period, high magnetic field and high coercivity. Using P r2F e14B instead of N d2F e14B, which is generally employed for undulators, avoids the limitation caused by the Spin Reorientation Transition phenomenon, and simplifies the cooling system by allowing the working temperature of the undulator to be directly at the liquid nitrogen one (77 K). We describe here the development of a full scale (2 m), 18 mm period P r2F e14B cryogenic permanent magnet undulator (U18). The design, construction and optimization, as well as magnetic measurements and shimming at low temperature are presented. The commissioning and operation of the undulator with the electron beam and spectrum measurement using the Nanoscopmium beamline at SOLEIL are also reported.

A new concept of wiggler has been designed and realized at SOLEIL to produce high energy photons in low/intermediate electron storage rings. Instead of using the superconducting technology which requires new equipment and instrumentation, heavy maintenance, and additional running costs, we have proposed to build a compact in-vacuum small gap short period wiggler that operates rather at moderate field than at high field. The wiggler composed of 38 periods of 50 mm produces 2.1 T at a gap of 5.5 mm. The moderate value of the magnetic field enables one to limit the effects on the beam dynamics and to avoid excessive power and magnetic forces. In this purpose, the narrow magnetic system has been equipped with a counterforce device made of nonmagnetic springs. The roll-off resulting from the small size of poles has been compensated in situ by permanent magnet magic fingers. This paper reports the phases of design, construction, magnetic measurements, and on-beam tests of the in-vacuum wiggler WSV50.

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The availability of highly charged ion sources (electron cyclotron resonance or electron beam ion source) led in the last decade to many new scientific discoveries in various fields of atomic, solid state, and plasma physics. This article will review some of the most exciting results obtained in the field of the interaction of highly charged ions on surfaces in fundamental physics (hollow atom properties, mechanisms of electron captures and losses above, below, or at surface interactions…) as well as in applied physics (surface modifications, lithography, etc.). The deceleration and monochromatization of the ion beams delivered by the ion sources will be discussed in the framework of their use in the study of the ion surface interactions.