0 Assigned ID: 4507 ----- Attempting Submission 1 (Wed May 24 18:53:00 GMT 2023) ----- While significant efforts have been made to provide molecular line lists at optical and infrared wavelengths, there is a critical gap in our knowledge of molecular opacities relevant to exoplanetary atmospheres, particularly at UV wavelengths. The lack of comprehensive UV line lists for many species and/or the absence of measured temperature-dependent opacities pose a significant threat to accurate interpretation of exoplanet atmospheres. This is particularly pressing for HST where nearly 300 orbits in Cycle 30 alone are devoted to MUV-NUV observations of transiting exoplanets. We propose to build a robust open-source accessible database of MUV-NUV opacities for a curated set of seven high-priority species that can be leveraged for the reproducible interpretation of past, current, and future HST UV exoplanet observations. We focus on seven sulfur-based species that: 1) are in dire need of higher fidelity opacities, 2) play an important role in the exoplanet atmospheric chemistry of hot gas giants, and 3) are expected to sculpt MUV-NUV HST observations of exoplanets. Ultimately, our work will be an asset the community and provide new methodology that can be further used to fill critical gaps in UV opacities relevant to exoplanet atmospheres. PI : Dr. Robert Hargreaves Robert Hargreaves is a member of the HITRAN team at the Center for Astrophysics where his expertise is in the validation, incorporation, and calculation of molecular line lists and absorption cross-sections for the HITRAN and HITEMP databases. He has conducted numerous investigations into the absorption and emission of molecules at high temperatures, specializing in molecules applicable to planetary atmospheres. Co-PI: Dr. Natasha Batalha Natasha Batalha specializes in determining the climate and chemical compositions of exoplanet atmospheres using transit and direct imaging spectroscopy. She does so by developing physical models (spectroscopic, cloud, climate) to predict atmospheric structures, that can then be matched to data from telescopes. Furthermore, all Batalha's models are publicly available, as she strives to create a field that is accessible and inclusive. Batalha also is involved in the dissemination of open data. She co-leads (with Co-I Lewis) the development of NASA's open data repository for exoplanet opacities, MAESTRO. Co-I #1: Dr. Iouli Gordon Dr. Gordon is the director of the HITRAN molecular spectroscopic database project. HITRAN and its sister database HITEMP are widely used in atmospheric and astrophysical applications. His areas of expertise include a) laboratory and theoretical molecular spectroscopy of atmospheric and astrophysical interest; b) use of available spectroscopic information to construct databases that aid research in diverse areas of science and industry; c) development of the tools for validating the spectroscopic data and enhancing its accessibility. Dr. Gordon is an active advocate of open scientific data and open-source codes. Co-I #2: Dr. Nikole Lewis Nikole Lewis is an expert in exoplanet atmospheric theory and observational characterization. She has participated in dozens of studies leveraging more than 1000 orbits worth of HST in the UV to NIR. Co-I #3: Dr. Katy Chubb Katy Chubb is an expert in computing molecular opacities from line lists at a wide range of temperatures and pressures, with experience adapting data format to fit a number of well-used atmospheric modelling and retrieval codes. She has ample expertise in comparing and combining laboratory and theoretical spectral data to ensure optimal accuracy and coverage, and in the practical use of such data in modelling and retrieving atmospheric properties of exoplanets. Co-I #4: Dr. Richard Freedman Richard Freedman is an expert in the computation of molecular opacities from line lists at a wide range of temperatures and pressures. Co-I #5: Dr. Robert Gamache Robert Gamache is an expert in the quantum theory of the interaction of radiation with matter, spectral line shapes, widths, and pressure shifts for molecules. Co-I #6: Dr. Ehsan Gharib Nezhad Ehsan Gharib Nezhad is an expert in spectroscopic measurement and theoretical calculation of molecular line lists, including line position, pressure-broadening coefficients, and line strength. He has also been a leading author and co-author of multiple studies on radiative transfer modeling of exo-atmospheres. Co-I #7: Dr. Ryan MacDonald Ryan MacDonald is an expert in radiative transfer, atmospheric modelling, and Bayesian atmospheric retrievals of transiting exoplanets. He has analysed Hubble transmission spectra of exoplanets spanning a wide range of planetary properties, including UV spectra of hot Jupiters obtained with WFC3/UVIS G280. He has also developed code to calculate molecular cross sections from line list databases. Co-I #8: Dr. Clara Sousa-Silva Clara Sousa-Silva is a theoretical spectroscopist and molecular astrophysicist with expertise in simulating both high-resolution and approximate spectral data for molecules, in wavelength ranges from the sub-mm to the ultraviolet. She also has experience in photochemical models and their spectroscopic inputs. Co-I #9: Prof. Jonathan Tennyson Jonathan Tennyson leads the ExoMol project and is also a contributor to HITRAN and HITEMP. He is an expert in the calculation and analysis of molecular spectroscopy, and is author of the text book Astronomical Spectroscopy. Co-I #10: Dr. Jeff Valenti Jeff Valenti co-maintains the Spectroscopy Made Easy (SME) radiative transfer and spectrum fitting package, which he has used to study missing UV opacity in the Sun and cool stars. He has experience observing cool stars, young stars, and stellar activity in the UV with HST. He is the JWST Mission Scientist at STScI. Co-I #11: Dr. Hannah Wakeford Hannah Wakeford is an expert in transiting exoplanet observations and spectroscopic analysis. Wakeford also has expertise in giant planet aerosols and their influence on measured exoplanet spectra. She is the PI of the Hubble Ultraviolet-optical Survey of Transiting Legacy Exoplanets (HUSTLE) treasury program that uses the newly proven capabilities of the WFC3/UVIS G280 grism to produce exoplanet transmission spectra from 200-800 nm. Co-I #12: Dr. Sergey Yurchenko Sergey Yuchenko is an expert in ab initio calculations of molecular line lists and developed the TROVE program to calculate rovibrational energies of spectra of general polyatmomic molecules. He is Professor of Physics at UCL and runs the ExoMol database together with Prof. Tennyson. Exoplanets and Exoplanet Formation 0 Regular false false true true false false SUPPORTED