I Congreso de Postgrado fcfm: ingeniería, ciencias e innovación

26 Santiago, 10 al 12 de agosto, 2022 A S T RONOM Í A 01 A SEARCH FOR CHEMISTRY IN THE ATMOSPHERE OF LTT 9779B USING ESPRESSO R. Ramirez Reyes ¹ * , and J. Jenkins ² , ³ ¹Departamento de Astronomía, Universidad de Chile, Camino el Observatorio 1515, Las Condes, Santiago, Chile. ²Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile. ³Centro de Astrofísica y Tecnologías y Tecnologías Afines (CATA), Casilla 36-D, Santiago, Chile. *Email: rramirez@das.uchile.cl ABSTRACT Context: LTT 9779 b is the first ultra-hot Neptune that was recently discovered using the Transiting Exoplanet Survey Satellite. The planet has a short orbital period of only 19 hours and an equilibrium temperature of ∼2000 K, and therefore lies in the middle of the Neptune Desert. However, even after two billion years of evolution embedded within the intense radiation field of the host star, it still maintains an atmospheric mass fraction of 10%. Aims. Using high SNR spectra at high spectral resolution from the ESPRESSO, we aim to search for atomic and molecular species within LTT 9779 b ’s atmosphere. Methods: Weappliedboth the transmissionspectroscopyandcross-correlation techniques todetect theatmospheric signals from Na, K, Hα, Ca, Fe, and V. We also model the Rositter-McLaughlin effect and the center to limb darkening effect to help identify any false positive signals. Results. With the current single transit dataset from ESPRESSO, we do not detect the presence of any of the aforementioned elements, from either of the methods we applied. We were able to determine upper limits for the abundances of each of the elements 3.0 [dex] for Na. Conclusions: Given previous work has confirmed the presence of the planetary atmosphere, has found a relatively high metallicity for the host star and has confirmed the planet has a mass and radius that places it close to that of Neptune, our non-detection of any elements here is suggestive that there are high-altitude absorbers present in the night-side terminator of the planet. AGRADECIMIENTOS A mi profesor guía que me a acompañado en todo este proceso y Elyar por ayudarme en los procesos de reducción de datos.