Resumo:
Differential spectrophotometry of transiting Hot-J´upiters has shown to be a promising technique to characterize the upper atmosphere of these planets, without
the necessity of spatially resolving it from its host star. The enhancement of this
technique in the last decade allowed the achievement of transmission spectra in
smaller telescopes, like the NOT 2.4m. Motivated by these results, this work aims
to test the viability of characterizing exoplanetary atmospheres applying this technique in the 1.6m Perkin Elmer telescope, based in observations performed in
OPD-LNA. The light curves obtained for the monitored objects showed a dispersion in the order of the transit depth, possibly generated by the oscillation of the
objects in the slit together with unfavorable nights. Through the combination of
the acquired spectra, it was possible to generate the transmission spectrum of the
WASP-87b. The atmospheric models adjusted to the data indicate an oxygen-rich
atmosphere (C/O < 1), with strong haze and evidence of TiO and VO absorber
structures, which at temperatures above 2000K, suppress the Na and K absorption lines. This individual result is not enough to confirm the effectiveness of
the method, and new observations must be made in order to better understand
systemic errors and restrict the limits of its applicability
