SCANDARIATO, GAETANOGAETANOSCANDARIATOBORSA, FrancescoFrancescoBORSABONOMO, ALDO STEFANOALDO STEFANOBONOMOGaudi, B. S.B. S.GaudiHenning, Th.Th.HenningIlyin, I.I.IlyinJohnson, M. C.M. C.JohnsonMalavolta, L.L.MalavoltaMallonn, M.M.MallonnMolaverdikhani, K.K.MolaverdikhaniNASCIMBENI, VALERIOVALERIONASCIMBENIPatience, J.J.PatiencePINO, LorenzoLorenzoPINOPoppenhaeger, K.K.PoppenhaegerSchlawin, E.E.SchlawinShkolnik, E. L.E. L.ShkolnikSICILIA, DanielaDanielaSICILIASOZZETTI, AlessandroAlessandroSOZZETTIStrassmeier, K. G.K. G.StrassmeierVeillet, C.C.VeilletWang, J.J.WangYan, F.F.Yan2024-03-272024-03-2720230004-6361http://hdl.handle.net/20.500.12386/35034Context. Hot giant planets such as MASCARA-1 b are expected to have thermally inverted atmospheres, which makes them perfect laboratories for atmospheric characterization through high-resolution spectroscopy. Nonetheless, previous attempts at detecting the atmosphere of MASCARA-1 b in transmission have led to negative results. Aims. We aim to detect the optical emission spectrum of MASCARA-1 b. Methods. We used the high-resolution spectrograph PEPSI to observe MASCARA-1 (spectral type A8) near the secondary eclipse of the planet. We cross-correlated the spectra with synthetic templates computed for several atomic and molecular species. Results. We detect Fe I, Cr I, and Ti I in the atmosphere of MASCARA-1 b with a S/N ≈ 7, 4, and 5, respectively, and confirm the expected systemic velocity of ≈ 13 km s-1 and the radial velocity semi-amplitude of MASCARA-1 b of ≈200 km s-1. The detection of Ti is of particular importance in the context of the recently proposed phenomenon of Ti cold-trapping below a certain planetary equilibrium temperature. Conclusions. We confirm the presence of an atmosphere around MASCARA-1 b through emission spectroscopy. We conclude that the atmospheric non-detection in transmission spectroscopy is due to the strong gravity of the planet and/or to the overlap between the planetary track and its Doppler shadow.STAMPAenArticle10.1051/0004-6361/2022455392-s2.0-85162186663https://www.aanda.org/articles/aa/full_html/2023/06/aa45539-22/aa45539-22.htmlFIS/05 - ASTRONOMIA E ASTROFISICA