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The circumstellar disk of the Herbig Fe star HD 142527 is host to several remarkable features including a warped inner disk, a 120 au-wide annular gap, a prominent dust trap and several spiral arms. A low-mass companion, HD 142527 B, was also found orbiting the primary star at $sim$14 au. This study aims to better characterize this companion, which could help explain its impact on the peculiar geometry of the disk. We observed the source with VLT/SINFONI in $H$+$K$ band in pupil-tracking mode. Data were post-processed with several algorithms based on angular differential imaging (ADI). HD 142527 B is conspicuously re-detected in most spectral channels, which enables us to extract the first medium-resolution spectrum of a low-mass companion within 0.1 from its central star. Fitting our spectrum with both template and synthetic spectra suggests that the companion is a young M2.5$pm$1.0 star with an effective temperature of $3500pm100$ K, possibly surrounded with a hot (1700 K) circum-secondary environment. Pre-main sequence evolutionary tracks provide a mass estimate of $0.34pm0.06 M_{odot}$, independent of the presence of a hot environment. However, the estimated stellar radius and age do depend on that assumption; we find a radius of $1.37 pm 0.05 R_{odot}$ (resp. $1.96 pm 0.10 R_{odot}$) and an age of $1.8^{+1.2}_{-0.5}$ Myr (resp. $0.75 pm 0.25$ Myr) in the case of the presence (resp. absence) of a hot environment contributing in $H$+$K$. Our new values for the mass and radius yield a mass accretion rate of $sim$5 $times 10^{-9} M_{odot}$ yr$^{-1}$ (2-3% that of the primary). Our results illustrate thus the potential for SINFONI+ADI to characterize faint close-in companions. The new spectral type makes HD 142527 B a twin of the well known TW Hya T-Tauri star, and the revision of its mass to higher values further supports its role in shaping the disk.
With the uniquely high contrast within 0.1 (Delta mag(L) = 5-6.5 magnitudes) available using Sparse Aperture Masking (SAM) with NACO at VLT, we detected asymmetry in the flux from the Herbig Fe star HD 142527 with a barycenter emission situated at a
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
We constrain the angular momentum architecture of HD 106906, a 13 $pm$ 2 Myr old system in the ScoCen complex composed of a compact central binary, a widely separated planetary-mass tertiary HD 106906 b, and a debris disk nested between the binary an
We present ALMA observations of the $98.5~mathrm{GHz}$ dust continuum and the $mathrm{^{13}CO}~J = 1 - 0$ and $mathrm{C^{18}O}~J = 1 - 0$ line emissions of the protoplanetary disk associated with HD~142527. The $98.5~mathrm{GHz}$ continuum shows a st
We report the discovery of a planetary-mass companion, HD 106906 b, with the new Magellan Adaptive Optics (MagAO) + Clio2 system. The companion is detected with Clio2 in three bands: $J$, $K_S$, and $L^prime$, and lies at a projected separation of 7.