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The SEPAGE spectrometer (Spectrometre Electrons Protons A Grandes Energies) was realized within the PETAL+ project funded by the French ANR (French National Agency for Research). This plasma diagnostic, installed on the LMJ-PETAL laser facility, is dedicated to the measurement of charged particle energy spectra generated by experiments using PETAL (PETawatt Aquitaine Laser). SEPAGE is inserted inside the 10-meter diameter LMJ experimental chamber with a SID (Diagnostic Insertion System) in order to be close enough to the target. It is composed of two Thomson Parabola measuring ion spectra and more particularly proton spectra ranging from 0.1 to 20 MeV and from 8 to 200 MeV for the low and high energy channels respectively. The electron spectrum is also measured with an energy range between 0.1 and 150 MeV. The front part of the diagnostic carries a film stack that can be placed as close as 100 mm from the target center chamber. This stack allows a spatial and spectral characterization of the entire proton beam. It can also be used to realize proton radiographies.

ArTeMiS is a submillimeter camera planned to work simultaneously at 450 μm, 350 μm and 200 μm by use of 3 focal planes of, respectively, 8, 8 and 4 bolometric arrays, each one made of 16 x18 pixels. In July 2013, with a preliminary setting reduced to 4 modules and to the 350 μm band, ArTeMiS was installed successfully at the Cassegrain focus of APEX, a 12 m antenna located on the Chajnantor plateau, Chile. After the summary of the scientific requirements, we describe the main lines of the ArTeMiS nominal optical design with its rationale and performances. This optical design is highly constrained by the room allocation available in the Cassegrain cabin. It is an all-reflective design including a retractable pick off mirror, a warm Fore Optics to image the focal plane of the telescope inside the cryostat, and the cold optics. The large size of the field of view at the focal plane of the telescope, 72 mm x 134 mm for the 350 μm and 450 μm beams, leads to the use of biconical toroidal mirrors. In this way, the nominal image quality obtained on the bolometric arrays is only just diffraction limited at some corners of the field of view. To keep a final PSF as much uniform as possible across the field of view, we have used the technic of manufacturing by diamond turning to machine the mirrors. This approach, while providing high accuracy on the shape of the mirrors, made easier the control of the two sub units, the Fore Optics and the cold optics, in the visible domain and at room temperature. Moreover, the use of the similar material (Aluminium alloy 6061) for the optical bench and the mirrors with their mount ensures a homothetic shrinking during the cooling down. The alignment protocol, drew up at the early step of the study, is also presented. It required the implementation of two additional mechanisms inside the cryostat to check the optical axis of the cold optics, in the real conditions of operation of ArTeMiS. In this way, it was possible to pre-align the Fore Optics sub unit with respect to the cold optics. Finally, despite the high constraints of the operating conditions of APEX, this protocol allowed to align ArTeMiS with respect to the telescope in a single adjustment. The first images obtained on the sky, Saturn with its rings, are given.

The neutronic performances of the MEGAPIE target will be studied using fission micro-chambers specially designed to stand the severe irradiation conditions of flux and temperature. The absolute neutron flux will be monitored on-line at different positions inside the target in order to studied its spatial and temporal variations. Together with the flux characterisation, actinide incineration potential of such target will be study through 241 Am and 237 Np isotopes. Prototype fission detectors and electronics have been successfully tested during the past three years at the High Flux Reactor of Laue Langevin Institute. The results of these tests are presented.

The MEGAPIE project, a 1-MW liquid lead-bismuth spallation target, has operated successfully at Paul Scherrer Institute in Switzerland. It constitutes the first step in demonstrating the feasibility of heavy liquid-metal target technologies for accelerator driven systems. With the 4-month irradiation phase now concluded, the experiment has provided unique data for a better understanding of the behavior of the target under realistic irradiation conditions. A complex neutron detector, which has journeyed throughout all of the irradiation inside the target and close to the proton beam, has been extracted along with metallic foil monitors. These have provided a measure of the total inner neutron flux. This paper aims to present the current developments in this analysis and in the Monte Carlo simulations that have been performed.

8 fission micro chambers will be inserted inside the central rod of the 1 MW liquid Pb‐Bi MEGAPIE target in order to study the transmutation of two major actinides and to measure the neutron flux at a level of 5%. These chambers were developed for high neutron fluxes and tested at Laue Langevin Institute.