+33 (0) 231 514 000 infos@sominex.fr


Tools for X Diagnosis of the “Laser Mégajoule”
(Imagers and Spectrometer).


The Laser Mégajoule aims at reproducing in the laboratory the physical conditions which are analogous to those encountered during the nuclear functioning of weapons, or which exist in the cores of planets and stars.

The matter is carried, in a few billionths of seconds, to temperatures of several tens of millions degrees, to pressures of tens of millions times higher than the atmospheric pressure, to densities of several hundreds of times that of the solid.

For the various experiments considered, many parameters must be thus measured in order to be compared with those which are predicted by the calculations.

These measurements are ensured by complex diagnostics tools called plasma diagnostics.

telescopic arm of the Diagnosis tool


SOMINEX brings its expertise in ultra-high vacuum for the manufacturing of complex mechanical elements for the large scientific instruments and its capacity to be integrated into the development planning , customer products, being based on its strong machining and subcontracting capacity.

precision mechanism working under vacuum


At the time of the preliminary stages, SOMINEX has participated, as a THALES subcontractor, to the industrialization study, which allowed, ever since the beginning of the project, taking into account and integrating the ultra-high vacuum and environmental specific constraints (electromagnetic disturbances, shock waves, splinters, intense X radiation and neutron radiation), until the finalization of the 3D models.

3D study under SolidWorks®


Within the framework of this project, SOMINEX has subsequently taken part in the manufacturing of three pieces of X diagnostics equipment, which consist of imaging devices (pinhole cameras, X microscopes), used for measuring the hydrodynamics of plasma according to space and time, and of a spectrometric device with broad band whose purpose is to characterize the emission of plasma and to deduce its temperature in this way. (See details from the CEA publication)

In the production phase, in partnership with THALES, SOMINEX has manufactured and assembled the diagnosis equipment in the gray room and has provided the necessary means of testing for the totality of the diagnostics, fulfilling the commitments of quality, cost and time imposed by the project.

assembly in the clean room


In the qualification phase, the diagnosis devices have been assembled by THALES on the EQUINOX installation of functional testing at the CEA DAM of Bruyère le Châtel in order to carry out the testing of these very complex equipments.

The first imager was operational at the time of the first experimental campaign of the LMJ carried out in October 2014.

electric and mechanical test


UVX 2010 – 10e Colloque sur les Sources Cohérentes et Incohérentes UV, VUV et X ; Applications et Développements Récents, pages 145 – 151, publié le 21 Mars 2011.

First X diagnostics for LMJ
R. Rosch, C. Reverdin, B. Villette, J.Y. Boutin, J.L. Bourgade, J.P. Jadaud, R. Marmoret, T. Beck, G. Soullié, P. Troussel, C. Trosseille, C. Zuber, H. Maury et A. Richard.
DAM, DIF, 91297 Arpajon, France.

We describe the first X diagnostics currently developed for the LMJ.

These are mainly dedicated to the installation qualification (measurement of the focal spot, control of the beam steering and balancing), but also to the diagnosis of the cavity, of the radiative transfer (measurement of X conversion output), to the hydrodynamics diagnosis (radiography experiments of hydrodynamic instabilities) to the imaging of DT microballs.

This first batch of diagnoses includes two systems of two-dimensional X multi-imagery associated with an obturator tube and with a system of mono-dimensional imagery with a camera with focal plane shutter.

These three systems of X imagery called “X imagers” measure the radiation in the range [500 eV–15 keV]. A diagnosis of broad band X spectrometry functioning in range [30 eV–20 keV] has also been developed.

The design of the diagnostics takes into account the problems of vulnerability of firing products, of Hard-X-Ray hardening, of gamma and neutrons, of tritium contamination.

The constraints related to the exploitation are also taken into consideration, since the human intervention within the diagnostics must be limited during an experiment campaign.

The concepts which are being taken forward for these diagnoses, as well as the characterization of a first model of X multi-imagery microscope are presented.

For more information, visit:


by telephone or email.

Didier Comble

Didier Comble

Chief Executive

+33 (0) 231 512 323

Franck Polidor

Franck Polidor

Project & Dévelopment Director

+33 (0) 231 514 021