Tools and methods

Tools and Methods

A large variety of tools is used in ECOGAL.


Astronomical observations. The multi-scale observation dataset used by ECOGAL will rest on a suite of multi-wavelength large-scale continuum and spectroscopic surveys of the Galaxy. On the large scales, data from satellites such as Herschel, Spitzer, and Wise, as well as from terrestrial telescopes such as APEX and VLA are already available in the VIALACTEA knowledge base. In the next years, we will include results from the astrometric satellite Gaia, as well as data from already approved ESO programs with APEX and ARO. The small-scale observations will be covered by JWST in space, and by the IRAM, VLA and ALMA interferometers. We have direct access to the Calypso, FAUST and ALMA-IMF large programs. Significant extensions are planned with JWST and ALMA via normal and large programs, and through the scientific use of a new receiver for ALMA as well as through our shares in the SDSS-V spectroscopic survey of the Galaxy and the polarization observations at NOEMA that we will obtain as part of ECOGAL. In short, we will put together a complete inventory of the conditions conducive for star and planet formation in the Milky Way.           

Theoretical tools. The multi-scale multi-physics numerical simulations performed in ECOGAL are based on two complementary code platforms, the adaptive mesh-refinement code RAMSES and the moving-mesh code Arepo. The Paris-Saclay and Heidelberg teams have been using them for several years and contributed to various key modules. To confront model data with astronomical measurements, synthetic observations are needed. This requires us to compute the emission properties at each location in the computational domain, and we have tools to do so. Then, the transport of photons towards a fictitious observer has to be calculated. Here, we use the codes RADMC-3D and POLARIS, both developed in Heidelberg. In a parallel line of research, we will continue to work on astrophysical models, which are necessary to interpret and understand simulation and observational data.

Instrument development and survey consortia. To reach our scientific goals we will extend the available observational database. First, we will contribute to the deployment of polarization capabilities at NOEMA, which will give us access to a unique instrument for measuring magnetic fields in the north. Second, we will contribute to the construction of the ALMA  Band 2+3 receivers. This will allow us to measure chemical and physical properties from clumps to disks. Third, we will join SDSS-V, which will provide us with 25 million spectra in the ISM to study stellar feedback. These investments allow us to connect multi-wavelength observations on Galactic scale with individual star forming regions and protoplanetary disks with unique accuracy, sensitivity and resolution.

Data analysis. Observational data and numerical simulations constitute the foundation of the unified model of the Galactic ecosystem that we will provide. However, ECOGAL is much more than this, it will create the synergic framework through which optical-to-radio data for tens-of-thousands of molecular clouds and hundreds-of-thousands of star formation sites will be analyzed back-to-back with state-of-the-art theoretical simulations, deploying innovative machine-learning techniques to transform this knowhow into a set of easy-to-use tools with decision-making capabilities that will become freely available. We will merge the infra-structure developed by the INAF team  for observations and by the Paris-Saclay and Heidelberg teams for simulations, and create a uniform platform to present ECOGAL results to the larger community. 


#11 - Last update : 06/23 2020