FEDELE , DAVIDEDAVIDEFEDELEFavre, C.C.Favre2021-12-172021-12-1720200004-6361http://hdl.handle.net/20.500.12386/31245Over million years of evolution, gas dust and ice in protoplanetary disks can be chemically reprocessed. There is evidence that the gas-phase carbon and oxygen abundances are subsolar in disks belonging to nearby star forming regions. These findings have a major impact on the composition of the primary atmosphere of giant planets (but it may also be valid for super-Earths and sub-Neptunes) as they accrete their gaseous envelopes from the surrounding material in the disk. In this study, we performed a thermochemical modeling analysis with the aim of testing how reliable and robust are the estimates of elemental abundance ratios based on (sub)millimeter observations of molecular lines. We created a grid of disk models for the following different elemental abundance ratios: C/O, N/O, and S/O, and we computed the line flux of a set of carbon-nitrogen and sulphur-bearing species, namely CN, HCN, NO, C<SUB>2</SUB>H, c-C<SUB>3</SUB>H<SUB>2</SUB>, H<SUB>2</SUB>CO, HC<SUB>3</SUB>N, CH<SUB>3</SUB>CN, CS, SO, H<SUB>2</SUB>S, and H<SUB>2</SUB>CS, which have been detected with present (sub)millimeter facilities such as ALMA and NOEMA. We find that the line fluxes, once normalized to the flux of the <SUP>13</SUP>CO J = 2-1 line, are sensitive to the elemental abundance ratios. On the other hand, the stellar and disk physical parameters have only a minor effect on the line flux ratios. Our results demonstrate that a simultaneous analysis of multiple molecular transitions is a valid approach to constrain the elemental abundance ratio in protoplanetary disks....STAMPAenArticle10.1051/0004-6361/202037927http://arxiv.org/abs/2005.03891v2https://www.aanda.org/articles/aa/full_html/2020/06/aa37927-20/aa37927-20.html2020A&A...638A.110FFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation