HD 95086 is an intermediate-mass debris-disk-bearing star.VLT/NaCo 3.8 ~ { } \mu m observations revealed it hosts a 5 \pm 2 \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 , suggesting 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 ’ = 3.6 \pm 1.0 mag and K _ { 1 } -L ’ = 2.4 \pm 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= 5 \pm 2 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 .