The measurement and characterization of tritium, for its monitoring in processes or its accounting in radioactive wastes, can be addressed with nonintrusive and nondestructive methods such as the standardized (American Society for Testing and Materials C1458-16) large-volume calorimetry (LVC) technique. This type of calorimeter is isothermal and measures the heat flow generated by tritiated objects. The heat flow is detected with Peltier sensors. They are strategically located around the tritiated object to measure thermal fluxes in all directions. This method is matrix independent, the typical relative uncertainty is less than 1%, and the duration depends on the thermal conductivity and the volume of the measured object. The tritium quantity is calculated thanks to the tritium-specific power (324 mW/g) assuming that 100% of the measured heat flux comes from tritium. This technique was applied for measuring tritiated drums or objects with volumes ranging from 1 to 250 L, more particularly, for the so-called LVC1380, which has been codeveloped and copatented by the CEA and KEP Technologies in France for drums bigger than 200 L. The new technology is based on the measurement of a differential heat flux on a measurement cell and a reference concentric cell without using a symmetrical reference cell. This device enables the quantification of tritium inventories in the waste drum, whatever the physical and chemical forms of tritium. The CEA has performed qualification tests of this calorimeter with ghost drums. The CEA now operates the LVC1380, and the first results in a tritium nuclear environment have been obtained with adsorbed tritiated water on zeolite inside molecular sieve traps (MST). This paper presents the measurement capabilities of this new LVC calorimeter and some illustrating results obtained with MST drums.

Tritium measurement in nuclear waste is a key to determine the type of repository. This technical note describes the methodology used to validate tritium measurement in various matrices using pyrolysis method with a new instrument available in the market. The efficiency obtained for tritium recovery in aqueous matrix, oil and concrete are respectively higher than 95%, 93%, and 85%.

Two major Inertial Confinement Fusion (ICF) projects are currently in progress. The US program at the National Ignition Facility (NIF), which has taken its first firing of a cryogenic target with DT fuel this year, mainly relies on cryogenic targets with capillary filled capsule [1]. For the French ICF experiments carried out on the Laser MegaJoule (LMJ), the nominal filling path of cryogenic target assemblies (CTAs) is permeation of DT fuel through the microshell 121 The CEA Valduc tritium facilities, where targets are filled, are thus original installations with specific designs and technologies.This paper deals with the description of the tritium facilities for the LMJ cryogenic targets (twelve gloveboxes are needed to deliver 6 CTAs at the same time). After a short presentation of the whole gloveboxes chain, the paper will focus on the heart of the plant: the filling and cooling station (IRCC: 4 gloveboxes). 3 out of 4 of these gloveboxes (LCCR, LCTC and LCPC) are at the moment under commissioning at the manufacturer's site. The last one (LCGC) has been delivered to CEA Valduc and is currently under testing with deuterium.A description of the IRCC design and specifications is given as well as the main results of the commissioning process.

Abstract As part of the French Inertial Confinement Fusion (ICF) program, CEA has developped Cryogenic Target Assemblies (CTAs) for the Laser MegaJoule (LMJ). These targets are filled by permeation with high pressure deuterium-tritium gas mixture. The evolution of the materials physical properties, particularly organic ones (PI and CHx), which compose the target is unknown in these hard conditions. The polyimide and CHx membranes permeation was studied in this context. The hydrogen and helium permeation parameters are unaltered for polyimide membrane after tritium ageing in the 20 K-300 K temperature range: KHe = 3.10-14 exp(-16040/RT) mol.m-1.s-1.Pa-1 KH2 = 2.10-14 exp(-16950/RT) mol.m-1.s-1.Pa-1 First results for the CHx hydrogen permeation parameters without ageing tritium have been obtained: KH2 = 7.10-13 exp(-10550/RT) mol.m-1.s-1.Pa-1 New CHx permeation results after tritium ageing are shortly waited.

To carry out laser plasma experiments on CEA laser facilities, a R&D program was set up and is still under way to deliver complex targets. For a decade, specific developments are also dedicated to "Ligne d'Intégration Laser" (LIL) in France and Omega facilities (USA). To prepare the targets intended for the first experiments on the Laser "Mégajoule" (LMJ) facility, new developments are required, such as cocktail hohlraum fabrication, gas barrier coating and foam shells developments. For fusion experiments on LMJ, an important program is also under way to elaborate the Cryogenic Target Assembly (CTA), to fill and transport the CTA and to study the conformation process of the DT layer.

As part of the French Inertial Confinement Fusion program, Commissariat a l'Energie Atomique has developed cryogenic target assemblies (CTAs) for the Laser Migajoule (LMJ) and a program in two stages for the permeation filling of these CTAs: (a) the permeation filling studies with the Study Filling Station cryostats and (b) the design and manufacturing of the whole operational chain of CTA filling facilities. This paper deals with the description of both the cryogenic studying and the filling facilities for the LMJ targets.

Summary  This is the first of a series of three papers meant to study the short- and long-term spectral modulation of primary cosmic rays above 2 GrV during the time from the IGY to the IQSY, for a large part of solar cycle No. 19, which showed the highest activity recorded so far, and a complex superposition of different kinds of conspicuous solarinduced interplanetary perturbations. In Part I we discuss the information on the modulation as gained by means of neutron monitor data, provided sufficient accuracy is reached; in fact this information covers a fair primary rigidity range and offers a time and rigidity resolution which is not reached by other experimental data. We also present and apply to the 1957–65 data an indirect calibration procedure for practically the whole network of the near-sea-level neutron monitors by means of seven latitude surveys performed by ship or by terrestrial vehicle. This procedure provides a set of daily latitude curves suitable for directly deriving the isotropic variation of the primary differential spectrum.

The "CEA cryogenic target fabrication project" includes materials and technological researches on the Cryogenic Target Assembly (CTA), the DT filling and cryogenic transport to the LMJ site, and the conformation of the DT solid layer. The Research program to deliver CTAs to LMJ in 2010 is described Some important experimental results have already been obtained and are presented.

This is the first of a series of three papers meant to study the short- and long-term spectral modulation of primary cosmic rays above 2 GrV during the time from the IGY to the IQSY, for a large part of solar cycle No. 19, which showed the highest activity recorded so far, and a complex superposition of different kinds of conspicuous solarinduced interplanetary perturbations. In Part I we discuss the information on the modulation as gained by means of neutron monitor data, provided sufficient accuracy is reached; in fact this information covers a fair primary rigidity range and offers a time and rigidity resolution which is not reached by other experimental data. We also present and apply to the 1957–65 data an indirect calibration procedure for practically the whole network of the near-sea-level neutron monitors by means of seven latitude surveys performed by ship or by terrestrial vehicle. This procedure provides a set of daily latitude curves suitable for directly deriving the isotropic variation of the primary differential spectrum.

In this Part IV we study the influence of the primary cosmic-ray modulation on the attenuation coefficient of the nucleonic component at different latitudes and altitudes. The direct investigation of the time behaviour of the station attenuation coefficients is based on the largest amount of refined data so far used,i.e. the revised data of the IGY neutron monitors 1957–1965 obtained in Part 1 and the IQSY supermonitor data 1965–1969. The results of the correlation between this time behaviour and the time changes of the nucleonic intensity are in agreement with the estimates based on the solar-cycle modulation of the primary spectrum found in Part III. The results are also presented in a form suitable to their use for an accurate pressure correction of the data of the network of neutron monitors.

In this Part IV we study the influence of the primary cosmic-ray modulation on the attenuation coefficient of the nucleonic component at different latitudes and altitudes. The direct investigation of the time behaviour of the station attenuation coefficients is based on the largest amount of refined data so far used,i.e. the revised data of the IGY neutron monitors 1957–1965 obtained in Part 1 and the IQSY supermonitor data 1965–1969. The results of the correlation between this time behaviour and the time changes of the nucleonic intensity are in agreement with the estimates based on the solar-cycle modulation of the primary spectrum found in Part III. The results are also presented in a form suitable to their use for an accurate pressure correction of the data of the network of neutron monitors.