Data availability and requirements relevant for the Ariel space mission

To fulfil its science requirements, the Ariel space mission[1] has been specifically designed to have a stable payload and satellite platform optimised to provide a broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify/characterize clouds and monitor the stellar activity. The chosen wavelength range, from 0.5 to 7.8 µm, covers all the expected major atmospheric gases from, e.g. H2O, CO2, CH4, NH3, HCN, H2S, through to the more exotic metallic compounds, such as TiO, VO, and condensed species.In the frame of the "Spectral Data and databases" working group, 50+ members of the Ariel science team and colleagues were invited to contribute to a White Paper entitled: "Data availability and requirements relevant for the Ariel space mission and other exoplanet atmosphere applications"[2]. The goal of this 70-pages work submitted for a publication to RASTI is to provide a snapshot of the data availability and data needs primarily for the Ariel space mission, but also for related atmospheric studies of exoplanets and brown dwarfs in general. It covers the following data-related topics: molecular and atomic line lists, line profiles, computed cross-sections and opacities, collision-induced absorption and other continuum data, optical properties of aerosols and surfaces, atmospheric chemistry, UV photodissociation and photoabsorption cross-sections, and standards in the description and format of such data. These data aspects are discussed by addressing the following questions for each topic, based on the experience of the "data-provider" and "data-user" communities: (1) what are the types and sources of currently available data, (2) what work is currently in progress, and (3) what are the current and anticipated data needs.  Our aim is to provide practical information on existing sources of data whether in databases, theoretical, or literature sources.In addition, a project on the GitHub platform - https://github.com/Ariel-data -has been created to foster collaboration between the communities. As an open access tool, GitHub provides huge advantages of forming direct dialogues and become a go-to place for both data users and data providers, even for those who are currently not directly involved in the Ariel consortium or in the field of exoplanetary science in general.References[1] G. Tinetti et al., ESA Definition Study Report},(2020) - https://sci.esa.int/documents/34022/36216/Ariel_Definition_Study_Report_2020.pdf[2]  K.L. Chubb, S. Robert, C. Sousa-Silva, S.N. Yurchenko, et al., RAS Techniques and Instruments, submitted (2024) - arXiv:2404.02188.