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Till date, only a handful exo-atmospheres have been well characterized, mostly by means of the transit method. Data show exoplanet atmospheres to be diverse. However, this is based on a small number of cases. Here we focus our study on the exo-atmosphere of Qatar-1b, an exoplanet that looks much like HD 189733b regarding its host star activity level, their surface gravity, scale height, equilibrium temperature and transit parameters. Thus, our motivation relied on carrying out a comparative study of their atmospheres, and assess if these are regulated by their environment. In this work we present one primary transit of Qatar-1b obtained during September, 2014, using the 8.1 m GEMINI North telescope. The observations were performed using the GMOS-N instrument in multi-object spectroscopic mode. We collected fluxes of Qatar-1 and six more reference stars, covering the wavelength range between 460 and 746 nm. The achieved photometric precision of 0.18 parts-per-thousand in the white light curve, at a cadence of 165 seconds, makes this one of the most precise datasets obtained from the ground. We created 12 chromatic transit light curves that we computed by integrating fluxes in wavelength bins of different sizes, ranging between 3.5 and 20 nm. Although the data are of excellent quality, the wavelength coverage and the precision of the transmission spectrum are not sufficient to neither rule out or to favor classic atmospheric models. Nonetheless, simple statistical analysis favors the clear atmosphere scenario. A larger wavelength coverage or space-based data is required to characterize the constituents of Qatar-1bs atmosphere and to compare it to the well known HD 189733b. On top of the similarities of the orbital and physical parameters of both exoplanets, from a long Halpha photometric follow-up of Qatar-1, presented in this work, we find Qatar-1 to be as active as HD 189733.
Previous secondary eclipse observations of the hot Jupiter Qatar-1b in the Ks band suggest that it may have an unusually high day side temperature, indicative of minimal heat redistribution. There have also been indications that the orbit may be slig
We present a phase-resolved, optical, spectroscopic study of the eclipsing low-mass X-ray binary, EXO 0748-676 = UY Vol. The sensitivity of Gemini combined with our complete phase coverage makes for the most detailed blue spectroscopic study of this
[Abridged] The transmission of light through a planetary atmosphere can be studied as a function of altitude and wavelength using stellar or solar occultations, giving often unique constraints on the atmospheric composition. For exoplanets, a transit
We present ground-based, spectroscopic observations of two transits of the ultra-hot Jupiter WASP-121b covering the wavelength range $approx$500 - 950 nm using Gemini/GMOS. We use a Gaussian process framework to model instrumental systematics in the
We report on novel observations of HAT-P-1 aimed at constraining the optical transmission spectrum of the atmosphere of its transiting Hot-Jupiter exoplanet. Ground-based differential spectrophotometry was performed over two transit windows using the