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Since the laser invention, the advent of X-ray Free Electron Lasers (FEL) half a century later, opens new areas for matter investigation. In parallel, the spectacular development of laser plasma acceleration (LPA) with several GeV beam acceleration in an extremely short distance appears very promising. As a first step, the qualification of the LPA with a FEL application sets a first challenge. Still, energy spread and beam divergence do not meet the state-of-the-art performance of the conventional accelerators and have to be manipulated to fulfill the FEL requirement. We report here on the undulator spontaneous emission measured after a transport manipulation electron beam line, using variable permanent magnet quadrupoles of variable strength for emittance handing and a demixing chicane equipped with a slit for the energy spread. Strategies of control electron beam position and dispersion have been elaborated. The measured undulator radiation provides an insight on the electron beam properties., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

The U15 is an in-vacuum undulator designed to operate at room temperature and at 70K. It is the first in-vacuum undulator designed, assembled and which will be used in SOLEIL’s storage ring that have support beams for magnets longer than 2 meters. A clear gap is felt in the technologies used for manufacturing and assembling compared to our standard 2m length in-vacuum undulators. This is due, in part, to the tolerances imposed by the maximum phase error admissible in SOLEIL’s storage ring. The poster will shine lights on those difficulties from a design and manufacturing point of view., Proceedings of the 9th Edition of the Mechanical Engineering Design of Synchrotron Radiation Equipment and Instrumentation Conference, MEDSI2016, Barcelona, Spain

Anatomix and Nanoscopium beamlines are collecting photons generated by two 5.5 mm gap in-vacuum insertion devices installed in a canted straight section. Simultaneous operation of those two beamlines requires particular precautions in terms of alignment of the electron (and photon) beam in the undulators. With the high stored beam current (500 mA), any mis-steering in the upstream undulator could quickly damage the downstream one. Using the classical beam position interlock to guarantee the undulators protection would have constrained too much the operation due to very restrictive position thresholds. Then the machine protection system has been modified to incorporate a new interlock based on the electron beam angle combining two BPM readings. A description of the system and its performances will be presented., Proceedings of the 4th International Beam Instrumentation Conference, IBIC2015, Melbourne, Australia

The ERC grant COXINEL aims at demonstrating experimentally Free Electron Laser (FEL) amplification with electrons generated by laser plasma acceleration (LPA). Because of the still limited electron beam performance (especially energy spread and divergence) in view of the FEL requirements, the electron beam transfer line has been specifically designed with adequate diagnostics and strong focusing variable strength permanent magnet quadrupoles, an energy de-mixing chicane and second set of quadrupoles for further dedicated focusing in the FEL interaction region, in a U20 in-vacuum undulator, enabling to operate at 200 nm with a 180 MeV electron beam. The first observation and transport of electrons in the COXINEL line is presented here., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

LUNEX5 (free electron Laser Using a New accelerator for the Exploitation of X-ray radiation of 5th generation) aims at investigating compact and advanced Free Electron Laser (FEL). It comprises one one hand a 400 MeV superconducting linac for studies of advanced FEL schemes, high repetition rate operation (10 kHz), multi-FEL lines, and one the other hand a Laser Wake Field Accelerator (LWFA) for its qualification by a FEL application, an undulator line enabling advanced seeding and pilot user applications in the 40-4 nm spectral range. Following the CDR completion, different R&D programs were launched, as for instance on FEL pulse duration measurement, high repetition rate electro-optical sampling. The COXINEL ERC Advanced Grant aims at demonstrating LWFA based FEL amplification, thanks to a proper electron beam manipulation, with a test experiment under preparation. As a specific hardware is also under development such as a cryo-ready 3 m long undulator of 15 mm period is under development., Proceedings of the 37th International Free Electron Laser Conference, FEL2015, Daejeon, Republic of Korea

The W164 out-vacuum wiggler was designed and built at SOLEIL with the double goal of producing high energy photons for the PUMA beamline (10 keV to 70 keV) and to be used as a modulator for the FEMTOSLICING project. The insertion device requires simultaneously reaching low resonant energy (1.55 eV) and high critical energy of photons (above 10 keV), leading to the choice of high field and large periods. The 3.28 m long wiggler is composed of 20 periods of 164 mm made of NdFeB magnets and vanadium permendur poles. The required effective field for the FEMTOSLICING is 1.53 T and the maximum total field reaches 1.8T at the minimum gap of 14.5 mm. The small transverse size of the poles was optimized to minimize the magnetic forces (8 tons maximum) resulting, together with the large field produced at minimum gap, to a large vertical dynamic field integral (DFI) inside the horizontal physical aperture of the chamber. A dedicated permanent magnet system was designed, constructed and installed at both wiggler ends to cancel the DFI at minimum gap. The construction of the wiggler, the results of the magnetic measurements and the effects on dynamics measured on electron beam are presented., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

LUNEX5 (free electron Laser Using a New accelerator for the Exploitation of X-ray radiation of 5th generation) aims at investigating the production of short, intense, coherent pulses in the 40-4 nm spectral range [1]. It comprises two types of accelerators connected to a single Free Electron Laser (FEL) for advanced seeding configurations (seeding with High order Harmonic in Gas, echo). A 400 MeV superconducting Linear Accelerator, adapted for studies of advanced FEL schemes, will enable future upgrade towards high repetition rate and multi-user operation by splitting part of the macropulse to different FEL lines. A 0.4 - 1 GeV Laser Wake Field Accelerator (LWFA) [2] will also be qualified by the FEL application. After the Conceptual Design Report, R&D has been launched on different sub components. Following transport theoretical studies of longitudinal and transverse manipulation of a LWFA electron beam enabling to provide theoretical amplification, a test experiment is under preparation., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The production of high fluxes in the hard X-rays region is a major issue on medium energy storage rings. It requires the installation of Insertion Devices with high magnetic field and a large number of periods. The construction of a superconducting wiggler has been first envisaged but reveals to be maintenance constraining, much more complex and expensive than the permanent magnet technology. A small gap in vacuum wiggler composed of 38 periods of 50 mm has been preferred. The compact magnetic system allows to produce in a limited space a magnetic field of 2.1 T in a small gap of 5.5 mm, whereas an auxiliary counterforce system based on non-magnetic springs compensate the magnetic forces (up to 8.5 Tons) acting between magnet arrays. The gap between jaws and the mechanical deformations have been controlled and corrected. Magic fingers corrections have been also performed to reduce the integrated multipoles and to minimize the 2nd order integrals resulting from the tight width of the wiggler poles. This paper presents the design of the wiggler, the construction, and the results of the measurements after magnetic corrections., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan