[P-EM11] 系外惑星

[PEM11-03] Unlocking the Chemical Composition of Ultra Hot Jupiters: A NIR High-Resolution Emission Spectroscopy Study of WASP-33b

*Stevanus Kristianto Nugroho^1,2、Ernst de Mooij³、Neale Gibson⁴、Hajime Kawahara⁵、Vivien Parmentier^6,7、Teruyuki Hirano^1,2,8、Masayuki Kuzuhara^1,2、Matteo Brogi^9,10,11、Jayne Birkby¹²、Motohide Tamura^13,1,2、Yui Kawashima¹⁵、Takayuki Kotani^1,2,8、Kento Masuda¹⁶、Christopher Watson³、Konstanze Zwintz¹⁴、Sayyed Ali Rafi¹³、IRD Team - (1.Astrobiology Center、2.National Astronomical Observatory of Japan、3.Astrophysics Research Centre, Queen’s University Belfast、4.School of Physics, Trinity College Dublin, The University of Dublin、5.Department of of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency、6.Atmospheric, Oceanic and Planetary Physics, Department of Physics, University of Oxford、7.Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange、8.Department of Astronomy, School of Science, The Graduate University for Advanced Studies (SOKENDAI)、9.Dipartimento di Fisica, Universit`a degli Studi di Torino、10.Department of Physics, University of Warwick、11.INAF-Osservatorio Astrofisico di Torino、12.Astrophysics, Department of Physics, University of Oxford、13.Department of Astronomy, Graduate School of Science, The University of Tokyo、14.Institute for Astro- and Particle Physics, University of Innsbruck、15.Cluster for Pioneering Research, RIKEN、16.Department of Earth and Space Science, Osaka University)

キーワード：Exoplanet atmospheres, High-resolution spectroscopy, Hot Jupiter, Exoplanet atmospheric composition

Using high-resolution spectroscopy, the atomic/molecular bands in the spectrum of an exoplanet are resolved into individual absorption lines. The variation of Doppler shifts caused by the planetary orbital motion enables absorption lines in the exoplanet spectrum to be distinguished from telluric lines. By combining thousands of unique absorption (or emission) lines, the atomic/molecular signatures can be identified unambiguously and detected at high significance. We performed high-resolution emission spectroscopy characterising the day-side of an ultra-hot Jupiter, WASP-33b, using the InfraRed Doppler instrument on the Subaru telescope. We confirmed our previous detection of OH emission at >9 sigma but only after the secondary eclipse. Through several tests, the non-detection of OH before the eclipse is likely due to astrophysical phenomena indicating that the spatial distribution of each chemical species is different and that we are probing the different parts of this 3D atmosphere. We also confirmed previous detection of Fe I, Si I, Ti I, and found evidence of the emission of Mg I and Mn I after combining all data sets, which, if confirmed, along with Ti I adds more chemical species that are detected on the day-side of an exoplanet.