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We present H band spectroscopic and Halpha photometric observations of HD 100546 obtained with GPI and MagAO. We detect H band emission at the location of the protoplanet HD 100546b, but show that choice of data processing parameters strongly affects the morphology of this source. It appears point-like in some aggressive reductions, but rejoins an extended disk structure in the majority of the others. Furthermore, we demonstrate that this emission appears stationary on a timescale of 4.6 yrs, inconsistent at the 2sigma level with a Keplerian clockwise orbit at 59 au in the disk plane. The H band spectrum of the emission is inconsistent with any type of low effective temperature object or accreting protoplanetary disk. It strongly suggests a scattered light origin, as it is consistent with the spectrum of the star and the spectra extracted at other locations in the disk. A non detection at the 5sigma level of HD 100546b in differential Halpha imaging places an upper limit, assuming the protoplanet lies in a gap free of extinction, on the accretion luminosity and accretion rate of 1.7E-4 Lsun and MMdot<6.4E-7Mjup^2/yr for 1Rjup. These limits are comparable to the accretion luminosity and rate of TTauri-stars or LkCa 15b. Taken together, these lines of evidence suggest that the H band source at the location of HD 100546b is not emitted by a planetary photosphere or an accreting circumplanetary disk but is a disk feature enhanced by the PSF subtraction process. This non-detection is consistent with the non-detection in the K band reported in an earlier study but does not exclude the possibility that HD 100546b is deeply embedded.
We present new $H$ (1.5-1.8 $mu$m) photometric and $K_1$ (1.9-2.2 $mu$m) spectroscopic observations of the young exoplanet HD 95086 b obtained with the Gemini Planet Imager. The $H$-band magnitude has been significantly improved relative to previous
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
We present new near-infrared Gemini Planet Imager (GPI) spectroscopy of HD 206893 B, a substellar companion orbiting within the debris disk of its F5V star. The $J$, $H$, $K1$, and $K2$ spectra from GPI demonstrate the extraordinarily red colors of t
Detecting polarized light from self-luminous exoplanets has the potential to provide key information about rotation, surface gravity, cloud grain size, and cloud coverage. While field brown dwarfs with detected polarized emission are common, no exopl
Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric composition and luminosity, which is influenced by their formation mechanism. Using the Gemini Planet Imager, we discovered a planet orbiting th