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Innovative, low-loss, and compact optical systems are essential to meet the experimental requirements of emerging novel radiation sources. The microchannel plate (MCP), a metamaterial-based optical device, shows promising potential for shaping, condensing, and focusing soft x-ray radiation at synchrotron radiation (SR) facilities. This study highlights the impact of MCP optical devices on SR beam condensing capability and their sensitivity to the degree of coherence by investigating the profile of transmitted beams through single and double MCP optical devices. Transmitted diffraction patterns of soft x-ray SR radiation change with energy and radiation modes. At 92 eV, the double MCP-based device affects the beam divergence and degree of coherence more than the single MCP. Moreover, the double MCP device shows potential as a condensing optics at shorter wavelengths, i.e., 480 eV. Experiments were performed at the available end-station of the Circular Polarization beamline at the Elettra synchrotron facility in Trieste, using a high-vacuum chamber with a hexapod system, providing the precise movement necessary to align these diffractive optics. The findings contribute to the development of innovative optical systems for SR and free-electron laser beamlines, paving the way for advanced experiments in spectroscopy, microscopy, and imaging in a wide energy range. [ABSTRACT FROM AUTHOR]

Laser-driven non-local electron dynamics in ultrathin magnetic samples on a sub-10 nm length scale is a key process in ultrafast magnetism. However, the experimental access has been challenging due to the nanoscopic and femtosecond nature of such transport processes. Here, we present a scattering-based experiment relying on a laser-induced electro- and magneto-optical grating in a Co/Pd ferromagnetic multilayer as a new technique to investigate non-local magnetization dynamics on nanometer length and femtosecond timescales. We induce a spatially modulated excitation pattern using tailored Al near-field masks with varying periodicities on a nanometer length scale and measure the first four diffraction orders in an x-ray scattering experiment with magnetic circular dichroism contrast at the free-electron laser facility FERMI, Trieste. The design of the periodic excitation mask leads to a strongly enhanced and characteristic transient scattering response allowing for sub-wavelength in-plane sensitivity for magnetic structures. In conjunction with scattering simulations, the experiment allows us to infer that a potential ultrafast lateral expansion of the initially excited regions of the magnetic film mediated by hot-electron transport and spin transport remains confined to below three nanometers. [ABSTRACT FROM AUTHOR]

FERMI is the seeded free electron laser (FEL) user facility at Elettra laboratory in Trieste, operating in the VUV to soft X-rays spectral range. In order to extend the FEL spectral range to shorter wavelengths, an increase in the linear accelerator (linac) energy from 1.5 GeV to 2.0 GeV is required. This result will be achieved by replacing the present old sections with the newly designed accelerating sections which can work at high gradient with lower transverse wakefields. After the successful testing of a short prototype, 354 mm in length, of a new high-gradient (HG) section that sustained an accelerating gradient of 40 MV/m with a breakdown rate (BDR) of 8 × 1 0 − 8 bpp, two 3.0 m HG structures with the same design were built and installed at the FERMI linac. We report here the recent experience on the conditioning and installation of the first high gradient sections and the operation of the spherical pulse compressor prototype, conditioned up to 100 MW output power with a power amplification factor of 3.5. [ABSTRACT FROM AUTHOR]

Abstract: The current activities and future perspectives involving the use of X-band technology at the Elettra Laboratory are presented. These are mainly related to the development of the FERMI@Elettra FEL project, a fourth generation light source facility, now under commissioning in Trieste. The facility, based on a seed scheme, requires sub-ps electron bunches (∼1kA), with very high optical qualities, at the entrance of the undulator chain. This is achieved by compressing the beam with two magnetic chicanes. A large effort has been undertaken to develop an X-band accelerating structure, to be installed downstream the first bunch compressor, before the magnetic chicane. In addition, we are also evaluating the possibility of extending the FERMI FEL wavelength capabilities beyond the foreseen limit of 4nm, by increasing the linac energy from 1.5GeV to 2.4–2.5GeV, using the X-band technology. [Copyright &y& Elsevier]

The FERMI@Elettra free electron laser (FEL) user facility is currently under construction at the Sincrotrone Trieste laboratory in Trieste (Italy). It will cover the wavelength range from 100 to about 5 nm in the fundamental and 3 or 1 nm using the third harmonic. We report the layout of the photon beam diagnostics section, the radiation transport system to the experimental area, and the photon beam distribution system. Due to the peculiar characteristics of the emitted FEL radiation (high peak power, short pulse length, and statistical variation of the emitted intensity and distribution), the realization of the diagnostics system is particularly challenging. The end users are interested in parameters such as the radiation pulse intensity and spectral distribution, as well as in the possibility to attenuate the intensity. In order to accomplish these tasks, a photon analysis, delivery, and reduction system is now under development and construction and is presented here. This system will work on-line producing pulse-resolved information and will let users keep track of the photon beam parameters during the experiments. [ABSTRACT FROM AUTHOR]

Abstract: FERMI@elettra is a fourth-generation light source user facility under construction at the Elettra Laboratory in Trieste, Italy. The high-quality 1.2GeV electron beam drives two-seeded Free Electron Lasers (FELs) in the wavelength range 100−10nm. Wavelength tunability, variable polarization and higher electron beam energies to reach even shorter output wavelengths are also in the machine delivery plan. This paper describes the physics processes that have been modelled to simulate FERMI@elettra and the computer codes used to optimize the machine design. The paper focuses on several design challenges and how these translate into modelling and simulation challenges. [Copyright &y& Elsevier]

Located on the site of the Elettra Sincrotrone in Trieste, Italy, the FERMI free-electron laser (FEL) is a user facility fed by a 1.5 GeV, 10 to 50 Hz, S-band radio-frequency linear accelerator (linac). The FEL is based on an external laser seeding scheme which allows lasing down to a fundamental wavelength of 4 nm. In order to achieve shorter wavelengths and improved beam quality, a high gradient upgrade to the facility has been proposed which will extend the current capabilities of the system allowing the generation of beams up to 1.8 GeV while keeping breakdown rates low enough for high machine up-time. This article presents the detailed RF analysis of a 3.0 m S-band, high gradient (HG) structure designed for the new FERMI linac upgrade. This HG structure is designed to provide a reliable accelerating gradient of 30 MV/m with a very low breakdown rate. To ensure the low breakdown rate, Electric-Coupled (EC) RF couplers, also known as waveguide couplers, were designed for the HG structure. To demonstrate the reliability and feasibility of the upgrade plan, a short prototype was built in collaboration with Paul Scherrer Institute (PSI), Switzerland. Using a newly commissioned S-band cavity test facility, the short prototype was successfully conditioned to an accelerating gradient of 40 MV/m with a pulse length of 600 ns at a breakdown rate of 8 × 1 0 − 8 bpp. A comprehensive overview of the testing facility, its data processing tools and the conditioning of this short prototype will be illustrated. Concluding the paper is a visual inspection of the cells for signs of damage resulting from RF breakdown during the high power testing. [ABSTRACT FROM AUTHOR]

Highlights the 2003 Elletra Users' Meeting at the International Centre for Theoretical Physics on December 2, 2003 in Trieste, Italy. Pledge of the Italian government for funding the construction of FERMI, a free electron laser; Presentation of the Fonda-Fasella prize reward to scientist Kanchan Anand; Provision of entertainment by a rock band.

From November 24-26, 2008, the annual Elettra Users Meeting was held at the International Centre for Theoretical Physics in Trieste. The event followed the now customary formula of two scientific workshops, each of just over a day, with the relatively brief Users Assembly between the two. This year's workshops focused on two important objectives of Sincrotrone Trieste: applications of the Fermi free electron laser, which is under construction, and developing the life science user community of Elettra. [ABSTRACT FROM AUTHOR]

The article focuses on the FERMI@Elettra free electron laser (FEL) user facility in Trieste, Italy, which is said to be the first of its kind to implement seeding. The FEL will be able to reach shorter wavelengths which would result in coherent and stable high-gain light pulses. Seeding is said to eliminate reliance on spontaneous electron organization. FEL design team consultant William Barletta noted that seeded beams will be present in most future machines in the soft x-ray region.

From March 26 to 28, 2008, a workshop on “Timing and Synchronisation” was organized at Sincrotrone Trieste by the Italian research organizations INFN, ENEA and Sincrotrone Trieste. It brought together more than 30 experts from Europe and the United States to discuss the technology necessary to provide precise (picosecond to femtosecond range) timing, which is fundamental to a number of new fourth generation light source projects. These new Free Electron Lasers include FLASH in Hamburg, Fermi and the LCLS, which are under construction, and SPARX. They require not only the synchronization of the radio frequency systems, which in any case need to be more precise than in previous generations of accelerators, but also accurate synchronization of lasers for devices such as photo-injectors, laser heaters and seed lasers. [ABSTRACT FROM AUTHOR]