학술논문
Obliquity measurement and atmospheric characterization of the WASP-74 planetary system
Document Type
Working Paper
Author
Luque, R.; Casasayas-Barris, N.; Parviainen, H.; Chen, G.; Pallé, E.; Livingston, J.; Béjar, V. J. S.; Crouzet, N.; Esparza-Borges, E.; Fukui, A.; Hidalgo, D.; Kawashima, Y.; Kawauchi, K.; Klagyivik, P.; Kurita, S.; Kusakabe, N.; de Leon, J. P.; Madrigal-Aguado, A.; Montañés-Rodríguez, P.; Mori, M.; Murgas, F.; Narita, N.; Nishiumi, T.; Nowak, G.; Oshagh, M.; Sánchez-Benavente, M.; Stangret, M.; Tamura, M.; Terada, Y.; Watanabe, N.
Source
A&A 642, A50 (2020)
Subject
Language
Abstract
We present new transit observations of the hot Jupiter WASP-74 b ($T_\mathrm{eq} \sim$ 1860 K) using the high-resolution spectrograph HARPS-N and the multi-colour simultaneous imager MuSCAT2. We refine the orbital properties of the planet and its host star, and measure its obliquity for the first time. The measured sky-projected angle between the stellar spin-axis and the planet's orbital axis is compatible with an orbit well-aligned with the equator of the host star ($\lambda = 0.77\pm0.99 \mathrm{deg}$). We are not able to detect any absorption feature of H$\alpha$, or any other atomic spectral features, in its high-resolution transmission spectra due to low S/N at the line cores. Despite previous claims regarding the presence of strong optical absorbers such TiO and VO gases in the atmosphere of WASP-74 b, the new ground-based photometry combined with a reanalysis of previously reported observations from the literature shows a slope in the low-resolution transmission spectrum steeper than expected from Rayleigh scattering alone.
Comment: Accepted for publication in Astronomy & Astrophysics. 12 pages, 8 figures, 5 tables
Comment: Accepted for publication in Astronomy & Astrophysics. 12 pages, 8 figures, 5 tables