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HD 95086 is an intermediate-mass debris-disk-bearing star. VLT/NaCo $3.8 mu m$ observations revealed it hosts a $5pm2 mathrm{M}_{Jup}$ companion (HD 95086 b) at $simeq 56$ AU. Follow-up observations at 1.66 and 2.18 $mu m$ yielded a null detection, s uggesting extremely red colors for the planet and the need for deeper direct-imaging data. In this Letter, we report H- ($1.7 mu m$) and $mathrm{K}_1$- ($2.05 mu m$) band detections of HD 95086 b from Gemini Planet Imager (GPI) commissioning observations taken by the GPI team. The planet position in both spectral channels is consistent with the NaCo measurements and we confirm it to be comoving. Our photometry yields colors of H-L= $3.6pm 1.0$ mag and K$_1$-L=$2.4pm 0.7$ mag, consistent with previously reported 5-$sigma$ upper limits in H and Ks. The photometry of HD 95086 b best matches that of 2M 1207 b and HR 8799 cde. Comparing its spectral energy distribution with the BT-SETTL and LESIA planet atmospheric models yields T$_{mathrm{eff}}sim$600-1500 K and log g$sim$2.1-4.5. Hot-start evolutionary models yield M=$5pm2$ M$_{Jup}$. Warm-start models reproduce the combined absolute fluxes of the object for M=4-14 M$_{Jup}$ for a wide range of plausible initial conditions (S$_{init}$=8-13 k$_{B}$/baryon). The color-magnitude diagram location of HD 95086 b and its estimated T$_{mathrm{eff}}$ and log g suggest that the planet is a peculiar L-T transition object with an enhanced amount of photospheric dust.
Context. {beta} Pictoris b is one of the most studied objects nowadays since it was identified with VLT/NaCo as a bona-fide exoplanet with a mass of about 9 times that of Jupiter at an orbital separation of 8-9 AU. The link between the planet and the dusty disk is unambiguously attested and this system provides an opportunity to study the disk/planet interactions and to constrain formation and evolutionary models of gas giant planets. Still, {beta} Pictoris b had never been confirmed with other telescopes so far. Aims. We aimed at an independent confirmation using a different instrument. Methods. We retrieved archive images from Gemini South obtained with the instrument NICI, which is designed for high contrast imaging. The observations combine coronagraphy and angular differential imaging and were obtained at three epochs in Nov. 2008, Dec. 2009 and Dec. 2010. Results. We report the detection with NICI of the planet {beta} Pictoris b in Dec. 2010 images at a separation of 404 pm 10 mas and P A = 212.1 pm 0.7{deg} . It is the first time this planet is observed with a telescope different than the VLT.
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