SchoGaN is a four-year proposal for an ambitious research project focused on the use of III-V Nitride materials to achieve GaN Schottky diode and associated frequency multiplier enabling the future development of high power terahertz (THz) frequency sources. The partners of SchoGaN project are three academic laboratories (CNRS-IEMN, CNRS-CRHEA and the LERMA) and a SME (T-Waves Technologies). The consortium brings the required know-how and expertise to achieve significant breakthroughs in the field of frequency multiplier and leading to the realization of high power, tunable, compact, portable, broadband, non-cryogenic THz sources vitally required for many new applications. In this consortium, IEMN and CRHEA bring a strong expertise developed for these last 20 years in III-Nitride technology and material growth, respectively. LERMA brings strong expertise in design, waveguide modelling and fabrication, and assembly of frequency multiplier circuit. T-Waves Technologies will evaluate our THz sources for industrial applications in imaging. The consortium is fully complementary to reach the objectives. It is recognized in our community that the terahertz frequencies range starts at the transition between millimeter and sub-millimeter wave, i.e. 0.3 THz and spreads up to the 10 THz. This large range offers a wide variety of applications: sensing molecules, security, imaging, space science and imaging, non-destructive testing, medical science, very high data rate wireless communications... However, to grow massively, these applications required low cost, compact, portable, reliable and non-cryogenic THz sources and, the most important, of high power level. Today, many technologies are in competition towards low cost and mass-market applications where THz sources are already a vital element. Actually, between the solid state world with the transistor and the optic world with the laser, we note, between 300 GHz and 10 THz, into the famous "THz Gap", that the availability of usable, effective, high power THz sources is tremendously lacking. The objective of the SchoGaN project is to respond to this lack. The only technology that has proven its potentials in the THz range relies on the frequency multiplier principle. The GaAs-based frequency multiplier chains delivers state of the art performance with an output power of 18 µW obtained at 2.58 THz and about 1 mW at 1 THz. However, even if these results are impressive, a large access to these power THz sources remains critical for mass-market applications. Despite the improvements in many technological and design aspects, all solutions cannot overcome the GaAs intrinsic electric field breakdown limitation and the limited thermal conductivity which both represent now the definitive bottlenecks. The search of a candidate exhibiting a high breakdown electric field combined with high thermal conductivity is therefore crucial. This candidate is the Gallium Nitride (GaN). The first bottleneck will be surpassed by its high breakdown electric field, 10 times larger than GaAs. The second bottleneck will be managed thanks to GaN and SiC substrate which present a thermal conductivity 3 and 10 times larger than GaAs, respectively. Both, high breakdown electric field and high thermal conductivity will increase the power handling capabilities of devices resulting in a high output power. It has been shown that the power handling capability of a GaN Schottky diode is almost one order of magnitude larger than its GaAs counterpart. The project addresses THz power sources based on the multiplication chain principle using Gallium Nitride Schottky diode. The signal generation using GaN Schottky diodes is expected to deliver an output power one order of magnitude higher than the current reference. That represents a technological breakthrough towards the next generation of THz sources based on multiplier principle. We target to reach 15 mW of power at 600 GHz, about 10 times the current state of the art.

Methane (CH4) emissions have to be reduced to reach the Paris Agreement objectives. Modeling approaches assimilating observations are expected to verify the effectiveness of mitigation policies by monitoring sectoral and regional emission changes based on atmospheric observations. These “top-down” approaches are appropriate to estimate CH4 net flux at the surface; however, they have critical weak points: an incomplete prior knowledge of CH4 natural emissions, and difficulties in disentangling overlapping sources from different sectors. The main natural sources of CH4 are inland water emissions: wetlands, peatlands, lakes, ponds… While global wetland emissions gridded products exist, none are available for other inland water systems, which are thus missing in the prior description of emissions forcing top-down approaches. Global estimates of inland water systems remain not consistent in terms of localization and magnitude. Thus, dynamical maps of these areas and their emissions based on same data sets, are necessary to ensure consistency and reduce uncertainties in CH4 emission estimates. 3D top-down approaches retrieving CH4 emissions are based on total CH4 observations only, at surface stations or from remote sensing, and solve for net fluxes at the surface or few individual sectors. However, CH4 observations are not sufficient to properly distinguished between sectors. Isotopic or co-emitted species such as ethane for oil and gas emissions, or carbon monoxide for biomass burning, could help better discriminating the emissions from different sectors and their trend. For this, the project coordinator’s team has newly developed an inverse system (CIF-LMDz-SACs) that integrates isotopic observations to constrain CH4 emissions. The AMB-M3 project aims at 1) producing the first consistent gridded product of CH4 emissions from wetlands, peatlands and lakes to be used for CH4 sources analysis and as input to global top-down models, and 2) discriminating CH4 sources by improving the capabilities of an inverse systems. In the first work package we will develop dynamical and consistent gridded CH4-centric inland water maps including information on vegetation and soil types (carbon content), over 1995-2020 based on the GIEMS-2 inundated data set. GIEMS-2, covering already 1995-2015, provides inundated extent and dynamics under dense vegetation, produces consistent surface water in semi-arid regions and accounts for satellite inter-calibration issues. Then CH4 emissions based on this new product will be estimated by upscaling density fluxes from the literature. Developments on CH4 emissions from wetlands and northern peatlands have been done in different versions of the ORCHIDEE land surface model. For the project, they will be integrated into the trunk version of the ORCHIDEE model to better simulate CH4 emissions and compared to previous estimations. The second work package will demonstrate the potential of adding ethane and carbon monoxide within the CIF-LMDz-SACs surface data constrained global inversions. Analyses will be performed to optimally combine different tracer constraints from both surface and satellite observations to take advantage of all available observations for regional analysis. Finally, AMB-M3 project will provide new estimates of CH4 sources and sinks at the global and regional scales over 2010-2020 based on up-to-date bottom-up (ORCHIDEE) estimates and top-down modelling system.

One of the major questions in modern physics is how life emerged on Earth and whether it is a general characteristic of our Universe. In addition to its own interest, understanding molecular complexity in space helps to understand the link between the young Solar System and its small bodies, in which today we detect complex molecules and even amino acids (as in comets and meteorites). Where these molecules come from? How and where did they form? What do they tell us about stars and planets formation? And last, but not least, atoms and molecules are the remote thermometers and barometers, as their observed line spectra can and are used to extract a mine of precious and often unique information. Grain-surface astrochemistry is facing new fascinating and challenging questions. Among them, three are particularly relevant for this project: - Is it possible to build a grain-surface chemistry starting from radical blocks, and if so, what will be the chemical routes? - Is the diffusion of radicals fast enough to compete with atom addition (and destruction)? - How to measure radicals in experiments, in realistic conditions ? - Is grain-surface chemistry fully compatible with the astronomical observations and the current astrochemical models? Or in other words, what ISM molecules form prevalently on the grain surfaces and when? Here we propose to join the forces between two groups with complementary laboratory expertise (LERMA and PIIM) and one with astrophysical, observations and modeling, expertise (IPAG). The immediate project goal is to understand how molecules diffuse, meet and mate on the grain surfaces in order to assess what COMs are formed on them and how. To reach it, we will compare dedicated laboratory experiments and include them in a new astrochemical code able, at the end of the project, to compare predictions with observations, and to better understand the role and limits of the solid-state chemistry in space. The work is organized in 3 connected tasks corresponding of our 3 expertises : 1) Diffusion of radicals and building-up molecules on surfaces. It includes i) the optimization of new source of radicals and the measurement of their diffusions ii) the systematic studies of the reactivity of specific chemical groups iii) in order to understand what is the limit of the complexity of COMs synthesized on surfaces 2) An innovative experimental set-up will be implemented at PIIM coupling low-temperature chemistry and electron spin resonance (ESR) to overcome our blindness to intermediate species. Once done, slow reactivity of radical with their molecular environment will be studied, simulating the early stage of ice mantle growth. The final goal is to study radical-radical chemistry that should occur during the formation of stars 3) We will build up a new code, from GRAINOBLE, that is able to simulate the experimental results. Only after this first step, it will be possible to extrapolate the experimental results to the ISM conditions, as well as having a better determination of physical parameters to be included in astrochemical codes. The natural end of this project will be to compare our understanding of the solid-state chemistry to observations, to evaluate its impact on the molecular growth and to diffuse our results.

LOFAR (the European LOw Frequency ARray) is the first of the new-generation radiotelescopes of the 21st century, that will culminate with SKA (Square Kilometer Array) after 2020. NenuFAR is a giant extension of LOFAR, that is also a powerful standalone low-frequency (LF) radiotelescope in the range 10-85 MHz. Its construction has started in 2014 in Nançay, supported by CNRS/INSU, Observatoire de Paris, Université d’Orléans/OSUC, and the FLOW consortium. NenuFAR is a compact antenna array (400 m in diameter) connected to the LOFAR receivers and to a local digitizer and beamformer (synthesizing narrow steerable 200 kHz beams in the sky up to a total instantaneous bandwidth of 150 MHz). We propose here to give NenuFAR the additional capability of a powerful LF imager with ~7’ resolution, by adding a realtime correlator, offline computing power, massive storage, and 6 small arrays (of 19 antennas each) within 3 km of the compact core. These extensions will considerably reduce the confusion noise limiting the imaging sensitivity of the instrument, down to about the thermal noise. The scientific topics that will greatly benefit from the use of NenuFAR in Standalone as an imager include: (a) in multi-frequency, long integration imaging: the detection of the cosmological HI signal from the “dark ages” to the reionization era through the "cosmic dawn", the systematic and sensitive search for yet unconfirmed LF radio signatures of exoplanets and star-planet plasma interactions (SPI), and the radio afterglows of high energy collapses generating gravitational waves and Gamma Ray Bursts ; (b) in snapshot imaging mode: the systematic sensitive search for fast radio transients in a broad field of view, including the prompt emission associated with gravitational waves, pulsar giant pulses, Fast Radio Bursts, and exoplanetary / stellar / SPI bursts ; Detection and study of ~10^5 galactic and extragalactic sources, with their diffuse LF emission, will also be made possible. For topics (a) & (b) the NenuFAR Radio Imager (NRI) will be in its frequency range the most powerful existing instrument before SKA (more powerful than LOFAR and the LWA), combining a high instantaneous sensitivity, very large total bandwidth, good angular resolution, and full polarization measurement capability. The proposed imaging capability, adding to its beamformer capability and its enhancement of LOFAR as a “Super Station” (LSS) will make NenuFAR a truly unique LF radio facility of the 21st century. In the SKA era, it will remain complementary to SKA in terms of spectral range and hemisphere. France has a strong expertise in development of imaging, calibration, deconvolution, and RFI mitigation algorithms for LF radioastronomy, that will be applied to and optimized for the NRI, preparing the exploitation of SKA. NenuFAR has received the official status of SKA pathfinder from the SKA office, for the experience it will bring in terms of hardware, algorithms, multimode operations (super-station / standalone beamformer / imager), and science preparation. The NRI will contribute to the organization and development of the French LF radio community – which started with the collective writing of a broad science case by 80 French and International scientists –, reinforcing its role and influence in Europe. The CNRS prospective in 2014 and the Haut Conseil TGIR in 2016 gave a high priority to the completion of NenuFAR (labelled “Infrastructure de Recherche” by the MESR), and the “Conseil Stratégique de Direction” of USN identified the NRI as the development of highest importance. The NRI project includes a Public Outreach part in the form of an Art Project integrated with the instrument and that will enhance its interest for the general public.

The Epoch of Reionization (EoR) is finally coming under the scrutiny of our instruments. The EoR is a period in the history of the universe spanning the first billion years (from z=20-30 to z=6). It begins when the light emitted by the first stars born from the gravitational collapse of primordial density fluctuations, start to ionize the surrounding intergalactic medium (IGM). The resulting ionized regions grow until they overlap, finally confining neutral hydrogen into small dense clumps embedded in vast diffuse regions of ionized gas by z~6. During this process the large scale properties of the universe are strongly connected to the small-scale physics of galaxy formation, making it complex to understand and model. Modeling the EoR, however, is vital as observations are becoming available and will improve drastically in terms of quality and quantity in the next few years. To mention but a few: observations with the WFC3 on HST have unveiled the galaxy luminosity function at z~8 and will improve much with the JWST, and 21cm observations of the neutral intergalactic medium are just around the corner, with LOFAR starting its survey in 2013-2014 and the SKA being built for 2020. The main driver of the ORAGE project is to make a large contribution to our understanding of the EoR though numerical simulations, giving us the theoretical understanding necessary to interpret the up-coming observations. The key process setting the pace of global reionization is the photon budget in primordial galaxies. How many are produced, how many escape into the IGM, how many are absorbed locally and possibly photo-evaporate the forming galaxy? Observations are scarce and the few existing simulations do not reach a consensus. The first task of ORAGE is to achieve a robust modeling of this photon budget. To this end, we will run radiative hydrodynamics (RHD) simulations. The members of this project have developed two (LICORICE and RAMSES-RT) of the less than ten existing codes for RHD in a cosmological context. We will develop a convergence project consisting in a series of tests in a cosmological setting and of increasing complexity in terms of modeling. We will run them with both codes and work on numerical methods until we reach convergent results. We will then set up a web site offering the tests for download and the possibility for developers to upload results of other codes, existing of new. Then, running a suite of very high-resolution simulations in sufficient volumes, we will study the properties of the sources of reionization. We intend to establish beyond current uncertainties how the fraction of ionizing continuum escaping from primordial galaxies depends on various environmental properties such as the mass of the host halo. Quantifying this behavior as a function fesc(M,…) will be an invaluable tool for interpreting observations or reusing as sub-grid physics in large scales simulations. We will also derive the stellar continuum and Lyman-alpha line emissions of a sample of objects at different z. This post-processing, using state-of-art population synthesis and detailed radiative transfer in the Lyman-alpha line, will provide observable quantities usable as templates to interpret observations with MUSE/VLT and JWST. We will also use our highly resolved simulations to study the reionization of the Milky Way. The satellites of the MW can serve as an archeological probe of the EoR: the impact of reionization on their properties can still be observed today. Moreover, reionization can be a solution to the well-known missing satellites problem. While RHD is necessary to study the formation of the first galaxies, it has not yet been included in studies of the reionization of the MW: we intend to do it. Finally we will implement the progresses made in our understanding of the small scale processes (such as fesc(M) ) into large scale simulations designed to produce robust simulated 21cm data cubes in preparation for observation by the SKA.